Written by Brady Holmer, BS, PhD(c); Edited by Dmitri Barvinok, BA; Reviewed by Morgan Pfiffner, MS

After our Webinar about tendon repair and the importance of isometric training, I came across this highly interesting meta-analysis. This analysis was conducted on 270 randomized controlled exercise studies. The exercise protocols were categorized into the following primary training modalities: aerobic exercise training, dynamic resistance training, combined (aerobic + resistance) training, high-intensity interval training (HIIT), and isometric exercise training. Subgroups were defined within each category: Aerobic exercise (walking, running, and cycling), HIIT (sprint interval training and aerobic interval training), Isometric exercise: handgrip exercise, leg extension, and wall squats. 

And the outcome was as follows:

Except combined training for DBP, all modalities of exercises were effective for reducing SBP and DBP. When exercise modes were ranked for their effectiveness in reducing SBP isometric exercise was the most effective (−10 mmHg), followed by combined training, resis­tance training, aerobic exercise training, and HIIT. The subgroup ranking was as follows: wall squats, leg extension, handgrip exercise, cycling, running, combined training, sprint interval training, resistance training, aerobic interval training, and walking. When exercise modes were ranked for their effectiveness in reducing DBP, isometric exercise (− 6 mmHg) was also the most effective, followed by resistance training, HIIT, combined training, and aerobic exercise training. Subgroup rankings were as follows: running, wall squats, handgrip exercise, leg extension, cycling, sprint interval training, resistance training, aerobic interval training, combined training and walking.

In summary isometric training is a perfect way for reducing both SBP and DBP. During isometric exercise, prolonged muscle contraction temporarily cuts off blood flow through the vasculature. After the exercise, the reactive hyper­aemia is leading to a large release of nitric oxide and the relaxation of blood vessels. This process improves the health and function of blood vessels and reduces blood pressure. 

Performing these isometric exercises with a larger muscle by doing wall squats or leg extension has an even greater effect. And this is why the ana­lysis shows that wall squats were the most effective exercise (SBP – 10 mmHg und DBP  – 6 mmHg).

However, if you take a look at the publications of recent years on the subject of autologous blood / platelet-rich plasma (PRP) injections, it is surprising that this type of therapy comes off so badly in the treatment recommendations. With the following article, I shall try to shed some light into this darkness and encourage you to think about the topic, above all for yourself. 

The current issue of “Osteoarthritis and Cartilage” deals with joint-preserving treatment recommendations for knee and hip osteoarthritis. This study assessed the levels of recommendations from international professional societies and summarised their results. Twenty-­five guidelines were included, seven of which were rated as “of higher quality”. In particular, the importance of exercise, weight management and patient education is emphasised. With regard to injection therapy, the guidelines recommend glucocorticoid injections for the knee joint. At the same time, however, the included recommendations advise against hyaluronic acid (HA) injections of the knee joint and PRP injections of the knee and hip joints [1]. In a recent issue of the German medical journal Deutsches Ärzteblatt, the topic is presented in a similar, albeit somewhat more differentiated, way. Here, glucocorticoids are recommended for short-acting pain control for refractory symptoms, but it is made clear that prolonged use increases the risk of cartilage loss and, subsequently, osteoarthritis progression. Based on the underlying guidelines, the evidence for the use of hya­luronic acid is rated as low, with the observation that high molecular weight hyaluronic acid could produce better results than low molecular weight hyaluronic acid. As regards injections with PRP, aspirates from bone marrow/adipose tissue or expanded mesenchymal stromal cells (MSC), the sources used to date do not provide any convincing evidence of longer-term therapeutic effects [2]. Unlike the two studies mentioned above, the European Society for Sports Traumatology, Knee Surgery and Arthroscopy (ESSKA) takes a very posi­tive stance on the use and evidence of injectable orthobiologics in the treatment of osteoarthritis of the knee in its ORBIT (ORthoBiologics InitiaTive) Consensus 2022. They recommend PRP for knees with moderate osteoarthritis, consider PRP to be safer than glucocorti­coids, especially with respect to the chondrotoxicity of cortisone, and favour PRP over HA. As far as the superiority of leukocyte-poor or leukocyte-rich PRP and the other differences between the individual PRP products are concerned, the ORBIT Group does not see sufficient scientific evidence to provide any recommendations. On the question of the number of injections, more than one is recommended [3].

Even though this is not a guideline or registered meta-analysis, it should be added that Jörg Jerosch, who unfortunately died far too early, also commented on injection therapy with cortisone, hyaluronic acid and PRP in one of his last review articles on the conservative treatment of osteoarthritis. He ascribes glucocorticoid injections a short-term positive effect in activated osteoarthritis of the knee but puts this into perspective by adding that hyaluronic acid injections are already superior after just eight weeks. With respect to the various HA preparations, he quotes that high molecular weight HAs show better clini­cal results than low molecular weight HAs. He gives a positive assessment of intra­articular PRP injections and refers exclusively to the above-mentioned ­ESSKA consensus paper [4].

PRP in the current literature

When looking at the recommendations given above [1, 2], it is somewhat surprising that the role of PRP in the treatment of knee and hip osteoarthritis in particular is presented so negatively, and that glucocorticoid injections are still recommended. The current literature actually takes a different view. Over recent months, various meta-analyses have appeared which report clearly posi­tive results in the use of PRP in large patient groups. Xue et. al. summarise 16 randomised and controlled studies with a total of 1652 patients which favour PRP over all other injectable substances with respect to pain, stiffness and function [5]. Large meta-analyses involving 1805, 1292 and 1042 patients reached similar results [6 – 8].

PRP and HA in the current literature

The majority of current comparative studies favour PRP in comparison with HA. In a meta-analysis, Belk et al. compared 811 patients after PRP injections with 797 patients after HA injections [9]. The PRP group demonstrated a better result as compared with the HA group with respect to various clinical scores (WOMAC, VAS and IKDC). In the PRP group, the leukocyte-poor preparations showed significantly better results than the leukocyte-rich preparations. Another meta-analysis invol­ving 1077 patients in the PRP group and 1009 patients in der HA group also reached similar results for the comparison between PRP and HA [10]. Current meta-analyses looking at the combination of PRP and HA are also very interesting. Thus, all available studies show no increased side effects rates for the combination of both preparations in comparison with single therapy with PRP or HA [11 – 13]. Interestingly, Zhang et. al even report that fewer side effects developed with combination therapy of PRP and HA than with single therapy with PRP. In terms of various clinical scores, the present meta-analyses show better results for a combination of PRP and HA in comparison with single therapy with PRP or HA [11 – 13].

The role of glucocorticoids

Here, too, a look at the current literature is somewhat surprising with respect to the statements made in the recommendations discussed at the beginning of this article [1, 2]. If PRP injections are compared directly with glucocorticoid injections, then significantly better results are found for patients after PRP injections [14]. Donavan et al. present similar results (also in “Osteoarthritis and Cartilage”), reporting that recurrent cortisone injections are clearly inferior to PRP or HA [15]. Even more decisive, however, is a look at various studies linking cortisone injections with an accelerated progression of osteoarthritis. For example, large groups of data from the „Osteoarthritis Initiative“ in the USA show that glucocorticoid injections are associated with an increased risk of needing a total knee replacement (TKR) in the course of the disease [16]. Another analysis of an even larger data­base shows very comparable results correlating dose-dependent intra-articular cortisone injections with an increased risk for knee replacement within the next five years [17].

Conclusion

If one looks at the current literature cited here (only sources from 2020 onwards), one gets the impression that the meta-­analyses cited from the large patient groups shown do not necessarily correspond to the statements of the first two recently published treatment recommendations. PRP treatment, especially of osteoarthritis of the knee, certainly has a good and positive foundation in the literature. The combination of PRP and HA injections, in particular, appears to be a safe and promising combination therapy. The intra-articular injection of glucocorticoids should be reviewed and carries the risk of progression of cartilage damage.

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Note from the editorial team

In this respect, see also the articles in by Prof. Dr. Oliver Werz / Dr. Markus Werner „Glucocorticoids – New mechanisms of action decoded – timing counts in therapy“ and by Aranka Brockmüller and Prof. Dr. Mehdi Shakibaei „Epigenetic efficacy of curcumin as a therapeutic goal in osteoarthritis“ & „Resveratrol – A pearl of nature with prophylactic, therapeutic and regenerative potential“. 

We would also like to draw your attention to further articles on osteoarthritis therapy, including those by Dr. Weisskopf, Prof. Dr. Jerosch and others, online on our sports medicine portal. 

In line with this topic

Following a decision by the German Federal Administrative Court, natural health practitioners are not allowed to take blood from their pa­tients to produce autologous blood products (Ref.No.: BVer­wG 3 C 3.22, BVerwG 3 C 5.22 and BVerwG 3 C 4.22).

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References

1. Gibbs AJ, Gray B, Wallis JA, et al. Recommendations for the management of hip and knee osteoarthritis: A systematic review of clinical practice guidelines. Osteoarthritis Cartilage 2023;31(10):1280-1292. DOI: 10.1016/j.joca.2023.05.015.
2. Ossendorff R, Thimm D, Wirtz DC, Schildberg FA. Methods of Conservative Intra-Articular Treatment for Osteoarthritis of the Hip and Knee. Dtsch Arztebl Int 2023;120(35-36):575-581. DOI: 10.3238/arztebl.m2023.0154.
3. Laura de Girolamo LL, Isabel Andia, Lars Blønd, Berte Bøe, Tomislav Cengic, Ignacio Dallo, Philippe Heuberer, Kaywan Izadpanah, Ladislav Kovacic, Koen Lagae, Laura Mangiavini, Jacques Menetrey, Stefan Mogos, Emmanuel Papakostas, Yiannis Pengas, Helder Pereira, Tim Spalding, Tomasz Piontek, Patricia Thoreux, Trifon Totlis, Kerem Tekin Ulku, Peter Verdonk, Yaniv Yonai, Stefano Zaffagnini ESSKA ORBIT Consensus Use of injectable orthobiologics for the treatment of knee osteoarthritis. ESSKA 2022.
4. Jerosch J. Konservative Schmerztherapie bei der Arthrose. Orthopädische und Unfallchirurgische Praxis 2023;12:236-243.
5. Xue Y, Wang X, Wang X, Huang L, Yao A, Xue Y. A comparative study of the efficacy of intra-articular injection of different drugs in the treatment of mild to moderate knee osteoarthritis: A network meta-analysis. Medicine (Baltimore) 2023;102(12):e33339. DOI: 10.1097/MD.0000000000033339.
6. Simental-Mendia M, Ortega-Mata D, Tamez-Mata Y, Olivo CAA, Vilchez-Cavazos F. Comparison of the clinical effectiveness of activated and non-activated platelet-rich plasma in the treatment of knee osteoarthritis: a systematic review and meta-analysis. Clin Rheumatol 2023;42(5):1397-1408. DOI: 10.1007/s10067-022-06463-x.
7. Cao Y, Luo J, Han S, et al. A model-based quantitative analysis of efficacy and associated factors of platelet rich plasma treatment for osteoarthritis. Int J Surg 2023;109(6):1742-1752. DOI: 10.1097/JS9.0000000000000337.
8. Belk JW, Lim JJ, Keeter C, et al. Patients With Knee Osteoarthritis Who Receive Platelet-Rich Plasma or Bone Marrow Aspirate Concentrate Injections Have Better Outcomes Than Patients Who Receive Hyaluronic Acid: Systematic Review and Meta-analysis. Arthroscopy 2023;39(7):1714-1734. DOI: 10.1016/j.arthro.2023.03.001.
9. Belk JW, Kraeutler MJ, Houck DA, Goodrich JA, Dragoo JL, McCarty EC. Platelet-Rich Plasma Versus Hyaluronic Acid for Knee Osteoarthritis: A Systematic Review and Meta-analysis of Randomized Controlled Trials. Am J Sports Med 2021;49(1):249-260. DOI: 10.1177/0363546520909397.
10. Kim JH, Park YB, Ha CW. Are leukocyte-poor or multiple injections of platelet-rich plasma more effective than hyaluronic acid for knee osteoarthritis? A systematic review and meta-analysis of randomized controlled trials. Arch Orthop Trauma Surg 2023;143(7):3879-3897. DOI: 10.1007/s00402-022-04637-5.
11. Zhang Q, Liu T, Gu Y, Gao Y, Ni J. Efficacy and safety of platelet-rich plasma combined with hyaluronic acid versus platelet-rich plasma alone for knee osteoarthritis: a systematic review and meta-analysis. Journal of orthopaedic surgery and research 2022;17(1):499. DOI: 10.1186/s13018-022-03398-6.
12. Karasavvidis T, Totlis T, Gilat R, Cole BJ. Platelet-Rich Plasma Combined With Hyaluronic Acid Improves Pain and Function Compared With Hyaluronic Acid Alone in Knee Osteoarthritis: A Systematic Review and Meta-analysis. Arthroscopy 2021;37(4):1277-1287 e1. DOI: 10.1016/j.arthro.2020.11.052.
13. Zhao J, Huang H, Liang G, Zeng LF, Yang W, Liu J. Effects and safety of the combination of platelet-rich plasma (PRP) and hyaluronic acid (HA) in the treatment of knee osteoarthritis: a systematic review and meta-analysis. BMC Musculoskelet Disord 2020;21(1):224. DOI: 10.1186/s12891-020-03262-w.
14. McLarnon M, Heron N. Intra-articular platelet-rich plasma injections versus intra-articular corticosteroid injections for symptomatic management of knee osteoarthritis: systematic review and meta-analysis. BMC Musculoskelet Disord 2021;22(1):550. DOI: 10.1186/s12891-021-04308-3.
15. Donovan RL, Edwards TA, Judge A, Blom AW, Kunutsor SK, Whitehouse MR. Effects of recurrent intra-articular corticosteroid injections for osteoarthritis at 3 months and beyond: a systematic review and meta-analysis in comparison to other injectables. Osteoarthritis Cartilage 2022;30(12):1658-1669. DOI: 10.1016/j.joca.2022.07.011.
16. Wijn SRW, Rovers MM, van Tienen TG, Hannink G. Intra-articular corticosteroid injections increase the risk of requiring knee arthroplasty. The bone & joint journal 2020;102-B(5):586-592. DOI: 10.1302/0301-620X.102B5.BJJ-2019-1376.R1.
17. Burnett RA, 3rd, Khalid S, DeBenedetti A, Terhune EB, Angotti ML, Della Valle CJ. Intra-articular corticosteroid injections are associated with a dose-dependent risk of total knee arthroplasty at 5 years. Knee Surg Sports Traumatol Arthrosc 2023;31(2):426-431. DOI: 10.1007/s00167-022-07017-z.

From a scientific point of view, this is clearly to be denied as it is now known that the natural polyphenol resveratrol, which is found in significant amounts in grapes of all colours, represents the central health-promoting component of red wine. After the discovery of this secon­dary plant substance in 1939, an extensive search for its origins began, yielding numerous fruits as natural sources of resveratrol. Apart from grapes, these include most berries, such as strawberries, mountain cranberries, blueberries, and red and black currants, as well as nuts such as peanuts and pistachios. But why do so many plants contain resveratrol? This phytoalexin protects them from infection, adverse weather conditions and premature over-ripening, thereby increasing the survival time of these fruit and plants.

THE EFFECT OF RESVERATROL ON THE HUMAN BODY

In view of this, the last few decades have been used to intensively investigate resveratrol’s effects on human cells and the human body. All in all, the investigations revealed a variety of effects that protect, maintain and defend our health. The phytopharmaceutical influences the metabolic as well as immune system and has both neuroprotective and cardioprotective effects. Interestingly, treatment with resveratrol increases the enzyme nitric oxide synthase, which is responsible for the production of the well-known cardiac vasodilator nitric oxide (NO). In addition to these prophylactic mechanisms, resveratrol is even able to inhibit the growth of cancer cells and increase the effect of classic chemo­therapeutic agents by sensitising the cells. This extensive modulation is based on a strict regulation of the inflammatory cascades around the main transcription factor of all inflammatory processes, known as nuclear factor kappa B (NF-kB).

In order to curb both acute and chronic inflammation, resveratrol restricts the secretion of pro-inflammatory cyto­kines and enzymes such as TNF-α, TNF-β, IFN-γ, COX-2, MMPs and various interleukins, thereby preventing the activation of NF-kB. However, the phosphory­lation of NF-kB itself and the pro­duction of its inflammation-promoting end products are also blocked by this natural polyphenol.  Additionally, the plant substance has an anti-oxidative effect in all organs and eliminates environmentally induced irritation in various tissues by balancing nitrogen oxides and reducing stress in cells.

Besides these catabolic options of intervention, resveratrol also utilises anabolic processes in healthy tissues and stabilises primary connective tissue cells such as osteocytes, chondrocytes and tenocytes. In this respect, a clinical study showed that the daily consumption of blueberries containing resveratrol significantly improved the quality of life of patients with symptomatic osteoarthritis of the knee joint by reducing pain and improving function.

It was also recently discovered that the intake of blackcurrant nectar by healthy volunteers leads to a significant reduction in sports-related muscle damage. Apart from its anti-inflammatory and anti-oxidant effects, this suggests that resveratrol also has regenerative potential. Fortunately, the phytopharmaceutical can be taken as part of a balanced diet or in regular doses as a supplement. So far, neither relevant side effects nor allergic reactions to resveratrol administration have been encountered in humans.

CONCLUSION

Overall, the regular use of resveratrol represents a promising preventive and (co-)therapeutic approach to complementary medicine and could also prove to be a multifunctional pearl of nature from a sports medicine perspective in the future.

References

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2. Takaoka M. The synthesis of resveratrol and its derivatives. Proceedings of the Imperial Academy 16.8, 1940, 405-407.
3. Ehala S, Vaher M, Kaljurand M. Characterization of phenolic profiles of Northern European berries by capillary electrophoresis and determination of their antioxidant activity. J Agric Food Chem. 2005 Aug 10;53(16):6484-90. doi: 10.1021/jf050397w. PMID: 16076138.
4. Tokuşoglu O, Unal MK, Yemiş F. Determination of the phytoalexin resveratrol (3,5,4′-trihydroxystilbene) in peanuts and pistachios by high-performance liquid chromatographic diode array (HPLC-DAD) and gas chromatography-mass spectrometry (GC-MS). J Agric Food Chem. 2005 Jun 15;53(12):5003-9. doi: 10.1021/jf050496+. PMID: 15941348.
5. Hain R, Reif HJ, Krause E, Langebartels R, Kindl H, Vornam B, Wiese W, Schmelzer E, Schreier PH, Stöcker RH, et al. Disease resistance results from foreign phytoalexin expression in a novel plant. Nature. 1993 Jan 14;361(6408):153-6. doi: 10.1038/361153a0. PMID: 8421520.
6. Brockmueller A, Sameri S, Liskova A, Zhai K, Varghese E, Samuel SM, Büsselberg D, Kubatka P, Shakibaei M. Resveratrol’s Anti-Cancer Effects through the Modulation of Tumor Glucose Metabolism. Cancers (Basel). 2021 Jan 7;13(2):188. doi: 10.3390/cancers13020188. PMID: 33430318; PMCID: PMC7825813.
7. Brockmueller A, Sajeev A, Koklesova L, Samuel SM, Kubatka P, Büsselberg D, Kunnumakkara AB, Shakibaei M. Resveratrol as sensitizer in colorectal cancer plasticity. Cancer Metastasis Rev. 2023 Jul 29. doi: 10.1007/s10555-023-10126-x. PMID: 37507626.
8. Brockmueller A, Girisa S, Kunnumakkara AB, Shakibaei M. Resveratrol Modulates Chemosensitisation to 5-FU via β1-Integrin/HIF-1α Axis in CRC Tumor Microenvironment. Int J Mol Sci. 2023 Mar 5;24(5):4988. doi: 10.3390/ijms24054988. PMID: 36902421; PMCID: PMC10003050.
9. Mobasheri A, Shakibaei M. Osteogenic effects of resveratrol in vitro: potential for the prevention and treatment of osteoporosis. Ann N Y Acad Sci. 2013 Jul;1290:59-66. doi: 10.1111/nyas.12145. PMID: 23855466.
10. Csaki C, Mobasheri A, Shakibaei M. Synergistic chondroprotective effects of curcumin and resveratrol in human articular chondrocytes: inhibition of IL-1beta-induced NF-kappaB-mediated inflammation and apoptosis. Arthritis Res Ther. 2009;11(6):R165. doi: 10.1186/ar2850. Epub 2009 Nov 4. PMID: 19889203; PMCID: PMC3003513.
11. Buhrmann C, Popper B, Aggarwal BB, Shakibaei M. Resveratrol downregulates inflammatory pathway activated by lymphotoxin α (TNF-β) in articular chondrocytes: Comparison with TNF-α. PLoS One. 2017 Nov 2;12(11):e0186993. doi: 10.1371/journal.pone.0186993. PMID: 29095837; PMCID: PMC5667866.
12. Velioğlu-Oğünç A, Sehirli O, Toklu HZ, Ozyurt H, Mayadağli A, Ekşioğlu-Demiralp E, Erzik C, Cetinel S, Yeğen BC, Sener G. Resveratrol protects against irradiation-induced hepatic and ileal damage via its anti-oxidative activity. Free Radic Res. 2009;43(11):1060-71. doi: 10.1080/10715760903171100. PMID: 19707923.
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Absence of ligament stabilisation together with medial displacement of the rotational axis of the knee joint result in significant translational instability of its lateral compartment. According to current study data, this injury can result in chronic translational instability of the knee joint in 75 – 87 % of cases after conservative treatment and in 8 – 50 % of cases after surgical management [10, 15, 16, 20]. This chronic instability has been shown to have a negative impact on the patient’s sports ability, the function of the knee joint and the patient’s quality of life, as well as towards accelerating the progression of osteoarthritis [2, 8, 14]. However, the choice of adequate treatment after an anterior cruciate ligament injury is still part of an ongoing scientific debate. In this article, we would like to take an up-to-date look at this still controversial issue, on which the Ligament Committee of the German Knee Society (DKG) has completed and published a consensus project [5, 11, 12]. According to current S1 guidelines (AWMF), ACL reconstruction using an autologous graft is indicated in cases associated with concomitant injuries to the collateral ligaments, repairable meniscal tears, and signi­ficant instability. According to meta-analyses and various cohort studies, it has been possible to reliably prevent secondary damage to the menisci and cartilage as well as to restore the previous level of activity to a large extent by ACL reconstruction [1, 9, 14].

ADEQUATE TREATMENT OF CONCOMITANT
PATHOLOGICAL CONDITIONS OFTEN REQUIRES SIMULTANEOUS ACL RECONSTRUCTION

An important prerequisite for deciding whether an ACL tear can be treated conservatively with a high probability of achieving a good result is the exclusion of relevant concomitant pathological conditions which, without surgical intervention, have a major bearing on the function and durabi­lity of the biological knee joint. The most important of these conditions is the complex meniscal tear, which has a good chance of healing after suturing but has a relevant negative impact on the joint if resected [11]. Many clinical studies have demonstrated beyond doubt the protective function of the menisci, with the lateral meniscus being of particular importance. Furthermore, the simultaneous stabilisation of the anterior cruciate ligament was shown to significantly improve the healing chances of a meniscal suture. Toman et al. demonstrated a meniscal healing rate of 70 – 92 % after simultaneous stabilisation of an ACL tear compared with a healing rate of 50 % without stabilisation  [11, 17, 19]. Apart from the need to stabilise the knee joint by means of ACL reconstruction, a stem cell-promoting effect of ACL surgery to support meniscal healing is also under discussion, which is why a one-stage treatment approach is recommended.

MANAGEMENT OF AN ISOLATED ACL TEAR

With regard to the treatment of a presumed isolated ACL tear, a prospective randomised study by Frobel RB et al. in particular has received a great deal of attention, and especially the lay press has suggested an equal value of surgical and conservative treatment [3, 4]. Taking a closer look at the study, however, the fact that it reveals a change from conservative to surgical treatment after five years in 51 % of the treatment groups must be viewed very critically, given that the results of these operated patients are attributed to the conservative group. However, other studies have also shown that delayed surgical management significantly increases the risk of secondary injuries to the menisci and cartilage [6]. In their cohort study, Sanders et al. found a five-fold increased risk of secondary meniscal tears after conservatively treated ACL ruptures compared with the surgically treated group [13].

ACL RECONSTRUCTION HAS A PROTECTIVE EFFECT AGAINST SECONDARY INJURY TO THE MENISCI AND CARTILAGE

Overall, evidence thus shows that ACL reconstruction has a protective effect on menisci and cartilage and can prevent secondary injuries [11]. Another prospective randomised study was published by Tsoukas D et al. in 2013. In contrast to the Frobel study, however, this trial found an advantage in favour of surgical treatment in terms of both functional knee scores and stability va­lues [18]. A systematic review of current studies was published in 2018 by Krause M. et al. in the German medical journal Deutsches Ärzteblatt [7]. The authors come to the conclusion that, based on the currently published RCTs (rando­mised controlled trials), no clear conclusion can be drawn as to whether surgical or conservative (wait and see) management leads to a better functional outcome. In observational studies, however, the authors were able to show a trend towards better results in favour of surgical management. Nevertheless, if concomitant injuries requiring urgent treatment have been ruled out and the patient has a moderate level of activity, a conservative treatment approach is prima­rily feasible. The patient should, how­ever, be closely monitored and thus enable any persistent or progressive instability to be recognised in order to reconsider whether surgery is now indicated. Secon­dary injuries after ACL insufficiency in particular are a signi­ficant problem that can be successfully minimised by means of ACL reconstruction.

CONCLUSION

Many new findings on the impact of the peripheral ligament structures (ALL, MCL), certain meniscal pathologies, and the significance of the tibial bony slope have considerably improved our understanding of individual ACL injuries and should be increasingly taken into account in future when deciding on tailored treatment for individual patients. Apodictic “surgery or conser­vative therapy” should be a thing of the past. This way, it is certainly possible to improve the results of our cruciate liga­ment patients, whether by conservative or surgical management.

References

1. Ajuied A, Wong F, Smith C, Norris M, Earnshaw P, Back D, Davies A (2014) Anterior cruciate ligament injury and radiologic progression of knee osteoarthritis: a systematic review and meta-analysis. The American Journal of Sports Medicine 42(9):2242–2252
2. Filbay SR, Culvenor AG, Ackerman IN, Russell TG, Crossley KM (2015) Quality of life in anterior cruciate ligament-deficient individuals: a systematic review and meta-analysis. Br J Sports Med 49(16):1033
3. Frobell RB, Roos EM, Roos HP (2010) A randomized trial of treatment for acute anterior cruciate ligament tears. … England Journal of …
4. Frobell RB, Roos HP, Roos EM, Roemer FW, Ranstam J, Lohmander LS (2013) Treatment for acute anterior cruciate ligament tear: five year outcome of randomised trial. Bmj Br Medical J 346(jan24 1):f232
5. Häner M, Stoffels T, Guenther D, Pfeiffer T, Imhoff A, Herbort M, Stein T, Schoepp C, Akoto R, Höher J, Scheffler S, Stöhr A, Mehl J, Niederer D, Jung T, Kittl C, Eberle C, Vernacchia C, Ellermann A, Braun P, Krause M, Mengis N, Müller PE, Best R, Achtnich A, Petersen W (2024) Management after acute injury of the anterior cruciate ligament (ACL). Part 3: Recommendation on surgical treatment. Knee Surg, Sports Traumatol, ArthroscDOI: 10.1002/ksa.12064
6. Keene GCR, Bickerstaff D, Rae PJ, Paterson RS (1993) The natural history of meniscal tears in anterior cruciate ligament insufficiency. Am J Sports Med 21(5):672–679
7. Krause M, Freudenthaler F, Frosch K-H, Achtnich A, Petersen W, Akoto R (2018) Operative Versus Conservative Treatment of Anterior Cruciate Ligament Rupture. Dtsch Ärzteblatt Int 115(51–52):855–862
8. Lai CCH, Ardern CL, Feller JA, Webster KE (2018) Eighty-three per cent of elite athletes return to preinjury sport after anterior cruciate ligament reconstruction: a systematic review with meta-an… – PubMed – NCBI. British Journal of Sports Medicine 52(2):128–138
9. Mall NA, Chalmers PN, Moric M, Tanaka MJ, Cole BJ, Bach BR, Paletta GA (2014) Incidence and Trends of Anterior Cruciate Ligament Reconstruction in the United States. Am J Sports Med 42(10):2363–2370
10. Meuffels DE, Favejee MM, Vissers MM, Heijboer MP, Reijman M, Verhaar JAN (2009) Ten year follow-up study comparing conservative versus operative treatment of anterior cruciate ligament ruptures. A matched-pair analysis of high level athletes. British Journal of Sports Medicine 43(5):347–351
11. Petersen W, Guenther D, Imhoff AB, Herbort M, Stein T, Schoepp C, Akoto R, Höher J, Scheffler S, Stoehr A, Stoffels T, Häner M, Hees T, Mehl J, Ellermann A, Krause M, Mengis N, Eberle C, Müller PE, Best R, Lutz PM, Achtnich A (2022) Management after acute rupture of the anterior cruciate ligament (ACL). Part 1: ACL reconstruction has a protective effect on secondary meniscus and cartilage lesions. Knee Surg Sports Traumatology ArthroscDOI: 10.1007/s00167-022-06960-1
12. Petersen W, Häner M, Guenther D, Lutz P, Imhoff A, Herbort M, Stein T, Schoepp C, Akoto R, Höher J, Scheffler S, Stöhr A, Stoffels T, Mehl J, Jung T, Eberle C, Vernacchia C, Ellermann A, Krause M, Mengis N, Müller PE, Best R, Achtnich A (2023) Management after acute injury of the anterior cruciate ligament (ACL), part 2: management of the ACL‐injured patient. Knee Surg, Sports Traumatol, Arthrosc 31(5):1675–1689
13. Sanders TL, Kremers HM, Bryan AJ, Fruth KM, Larson DR, Pareek A, Levy BA, Stuart MJ, Dahm DL, Krych AJ (2016) Is Anterior Cruciate Ligament Reconstruction Effective in Preventing Secondary Meniscal Tears and Osteoarthritis? American Journal of Sports Medicine 44(7):1699–1707
14. Sanders TL, Kremers HM, Bryan AJ, Larson DR, Dahm DL, Levy BA, Stuart MJ, Krych AJ (2016) Incidence of Anterior Cruciate Ligament Tears and Reconstruction: A 21-Year Population-Based Study. Am J sports Med 44(6):1502–7
15. Seitz H, Chrysopoulos A, Egkher E, Mousavi M (1994) [Long-term results of replacement of the anterior cruciate ligament in comparison with conservative therapy]. Chir Z fur alle Geb Oper Medizen 65(11):992–8
16. Smith TO, Postle K, Penny F, McNamara I, Mann CJV (2014) Is reconstruction the best management strategy for anterior cruciate ligament rupture? A systematic review and meta-analysis comparing anterior cruciate ligament reconstruction versus non-operative treatment. The Knee 21(2):462–470
17. Toman CV, Dunn WR, Spindler KP, Amendola A, Andrish JT, Bergfeld JA, Flanigan D, Jones MH, Kaeding CC, Marx RG, Matava MJ, McCarty EC, Parker RD, Wolcott M, Vidal A, Wolf BR, Huston LJ, Harrell FE, Wright RW (2009) Success of meniscal repair at anterior cruciate ligament reconstruction. The American Journal of Sports Medicine 37(6):1111–1115
18. Tsoukas D, Fotopoulos V, Basdekis G, Makridis KG (2015) No difference in osteoarthritis after surgical and non-surgical treatment of ACL-injured knees after 10 years. Knee Surgery Sports Traumatology Arthroscopy 24(9):2953–2959
19. Wasserstein D, Dwyer T, Gandhi R, Austin PC, Mahomed N, Ogilvie-Harris D (2013) A matched-cohort population study of reoperation after meniscal repair with and without concomitant anterior cruciate ligament reconstruction. The American Journal of Sports Medicine 41(2):349–355
20. Yperen DT van, Reijman M, Es EM van, Bierma-Zeinstra SMA, Meuffels DE (2018) Twenty-Year Follow-up Study Comparing Operative Versus Nonoperative Treatment of Anterior Cruciate Ligament Ruptures in High-Level Athletes. The American Journal of Sports Medicine 46(5):1129–1136

As the EMG application differs greatly in its areas of use, a general distinction has been outlined in Table 1. The use case described here addresses use cases A and B. An EMG mapping compares three activity states. The “Resting tone” is measured while standing and should not exceed a maximum activity of 15 µV (exept for pelvic floor/transversus area and the soleus muscle). If abnormalities are found, detonic measures should be considered and intensive activation can help. “Voluntary activation”, or the ability to intentionally activate a muscle, enhances an athlete’s control over their strength and can be significantly improved in just a few training sessions. “Involuntary activation” visualizes the muscle economy during movement and is mostly displayed as a balance score. High activity values reached in this test are not necessarily “good”. They may indicate weakness compensated by high effort (high activity). Therefore involuntary activity should always be interpreted in relation to resting tone and voluntary activation.

Mapping results should always lead to biofeedback training to improve both voluntary and involuntary activation. Muscle-specific strength can only be enhanced considering additional para­meters such as full ROM and adjusted resistance according to the individual strength goal. Dynamic training exercises are equally important to ensure targeted and rapid muscle activation ability in sport-specific movement. This should be illustrated using the selected use case for the gluteus medius of a professional football player.

The Importance of Gluteus medius

The GM is crucial for stabilizing the pelvis and supporting the lower back, leading to improved posture (pelvic control and hip stability) and movement efficiency. Its proper function can help prevent injuries in unilateral loading situations. The analysis of EMG scree­nings of 48 male football players from Germany’s top three leagues revealed significant variability in the voluntary activation of the gluteus medius (average: 430 µV [± 215 µV], range: 140 – 1133 µV). Similar patterns were observed in involuntary activation (average: 449 µV [± 168 µV], range: 219 – 1116 µV), with the highest averages found among players in the first Bundesliga. These data serve as guidance and do not claim strict scientific validity.

Case: exertion-dependent hip pain

The following case study illustrates the interplay of mappings and biofeedback training sessions of the gluteus medius based on an athlete with exertion-­dependent hip pain. In football, especially in the supporting leg, sagittal stability is crucial to ensure optimal performance and economy. Evaluating the neuromuscular function of the gluteus medius serves as an important para­meter in this regard.

Initial gluteus medius mapping (see Fig. 2 a)

At the beginning, a standardized mapping of the gluteus medius was done with the athlete. The mapping consists of 6 exercises in total and always starts with the rest position, which in this case showed good results far below the guideline of 20 µV. The second exercise is squeezing both glutes (voluntary activation) in which the player reached a balance score of 74 % ending up slightly below the symmetry goal of 80 %. 

A significant difference showed up in the unilaterally isolated activation exercises three and four. The left gluteus can be addressed «alone” and reached 119 µV at a balance score of 89 %. But the right gluteus only reached a 55 % balance score, as the left gluteus compensates when the athlete is asked to individually squeeze his right muscle.

The last exercise “one leg stands left and right” aim at the involuntary activation and have been unremarkable as they nearly reached the 400 µV guideline each side.

Biofeedback Training

In biofeedback training mode the player sees the muscle activity values of the EMG sensors in front of him on a tablet screen and visual goals in the EMG scale can be set (external focus). This setting helps the athlete to develop a basic sense of targeting his gluteus medius and is the basis to improve voluntary and “isolated” voluntary activation. The real time visual feedback enhances body awareness and the athlete`s motivation and compliance, all of which are important requirements for the exercises to come. 

To transfer learnings to involuntary movements, single-leg standing with external rotation of the raised leg have been introduced. It is crucial to ensure that the athlete can control the weight. If activity decreases or stagnates with increasing additional weights, it indicates compensation by other muscles. Voluntary (isolated) activation and single-leg standing with external rotation are excellent simple exercises for home or pre-training use to enhance conscious voluntary activation of the gluteus medius. Improvements should be noticeable with the first training session, at the latest after a few days of active practice. 

Targeting Tricks

Athletes can be assisted with their understanding of voluntary activation of the gluteus medius with two simple tricks. Trainers can locate the muscle and then press down with their thumb while athletes try to push it away actively. Additionally, initiating muscle contraction with external rotation of the leg during single-leg standing, can be beneficial. The gluteus medius becomes noticeably palpable at an external rotation of the lifted leg at approximately 30 degrees. 

Continuous use in Athletic Training

The athletic trainer added gluteus medius exercises to the athlete’s individual training plan. Measuring activation during strength exercises ensured correct execution and enhanced exercise efficiency. For example, during a side plank, complete pelvic thrusting often increases activation by up to 200 µV, highlighting the importance of small execution adjustments. EMG also aids in identifying compensatory patterns by monitoring the activity of muscles such as the tensor fasciae latae and biceps femoris, allowing trainers/therapists to make appropriate corrections.

First phase results (Fig. 2 b)

After three weeks of intervention, the resting tone of the athlete remained stable, and voluntary activation (Squeeze Your Glutes) has been significantly improved from 100 µV to 600 µV both sides. Since strength training is limited in the competition phase, this increase is less attributed to strength gains but rather can be explained by a considerably better voluntary activation. This is also evident in isolated voluntary activation (Squeeze Your Left/Right Glute) with higher µV values and better balance scores. The involuntary exercises (One Leg Stand) also recorded higher values but an asymmetry of 69% balance score occurred, which has been addressed in the next training phase.

Re-Test in Mid-Season Screening (Fig. 2 c)

After a period without intensive EMG supervision and mapping, the presented athlete was reexamined during the team’s mid-season screening. Voluntary activation remained good but showed a left-dominant imbalance and slightly increased activity of the passive muscle on each side. These patterns may have developed due to the absence of targeted training for conscious voluntary activation. Remarkably, there was a significant decrease in the involuntary activation of the gluteus medius during the One Leg Stand on the right, returning to the value of the initial mapping (see Fig. 2 A). This highlights how quickly muscle activation can change. It can be unlearned without regular training but also rapidly improved again by targeted biofeedback training. Figure 3 shows this development over the three different measurements of the athlete for the exercise Squeeze Your Right Glute. It shows the increase after 3 weeks intervention and a slight decrease after 6 months.

Conclusion

EMG screenings provide deep insights into muscle activity and support indivi­dual diagnostics. Biofeedback training improves the muscle activation ability and assists the athlete intuitively with the efficient execution of exercises. 

With the multitude of diagnostics presented to athletes, it can be challenging to stimulate their engagement and motivation. Biofeedback training, offering immediate visual feedback and showing positive changes, can have a positive supportive effect. 

Successful integration of EMG into athletic routines requires user-friendly, intuitive, preferably wireless systems for flexible and effective use. The opportunity to rapidly collect and interpret data is crucial in professional sports.

A recent SoccHealth study investigating the health of ex-professional soccer players reveals that around half of all female, and two thirds of all male, former professional football players between the ages of 40 and 69 years already suffer from OA. Despite its high prevalence as one of the most common causes of human disability worldwide, no effective treatment has emerged to date. That is why we need to broaden our knowledge of the underlying mechanisms of action of OA in order to find new therapeutic targets that slow down, or halt, the progression of the disease. There is unmistakable evidence that numerous environmental factors induce epigenetic changes promoting the development of the various manifestations of OA. Therefore, research into the role of epigenetics has become a current challenge in order to emphasise its causal relation­ship and importance in OA at the therapeutic level.

Epigenetics

Epigenetics is the study of the effects that lifestyle choices have on the gene expression of living organisms. In this context, various external environmental factors such as inflammation, inappropriate nutrition, metabolic disorders, oxidative stress, trauma, infections, and ageing lead to changes that can cause DNA methylation or histone modifi­cations, meaning methyl or acetyl groups on the histones. Epigenetic processes there­fore determine which genes are read and thus have an impact on the body and which genes are silenced without causing a mutation, i. e. no change is made to the genetic information in the genome. It is now known that the disruption of numerous essential cartilage-specific proteins during the development of OA is caused by aberrant epigenetic regulatory mechanisms and contributes to the development and progression of OA. In addition, currently approved conventional drugs, such as non-steroidal anti-inflammatory drugs (NSAIDs) and corticosteroids, which are commonly used to treat OA, have well-documented and potentially significant side effect profiles with long-term use, including cartilage tissue degradation. This emphasises the possibility of considering new therapeutic targets that may alleviate OA disease.

Phytopharmaceutics as an option

With the promising and growing recognition of inflammation as a major cause of OA, the effectiveness of curcumin (from the plant Curcuma longa), with its exceptionally potent anti-inflammatory and anti-oxidative properties, has emerged in recent years as a remarkable natural agent for the prevention, containment, and treatment of patients with OA. Against the background that curcumin inhibits pain and the degradation of the extracellular matrix (ECM), inflammatory genes and enzymes (nuclear factor kappa B, NF-kB; cyclooxygenase-2, COX-2; matrix metalloproteases, MMPs), and the secretion of inflammatory messengers (cytokines such as TNF-α, IL-1β) in OA, a simultaneous anabolic effect was observed in cartilage tissue (ECM synthesis such as collagen type 2, cartilage-specific proteoglycans), together with the activation of the cartilage-specific trans­cription factor SOX9 and enhancement of cartilage tissue regeneration. Interestingly, the side effects of this approach do not appear to be significantly different from placebo controls and were generally considered to be low, making this phytopharmaceutical an attractive alternative for patients for whom NSAIDs or cortisone are contraindicated.

Additionally, curcumin can also be of great nutritional benefit to healthy people. As described above, its positive impact on the prevention of various diseases is of decisive advantage, as the internal functions of organs are supported above all by its significant anti-inflammatory and anti-oxidative properties. In daily use, the phytopharmaceu­tical can also reduce feelings of anxiety, suppress inflammation in the musculoskeletal system after sport, promote performance and regeneration, and help protect human skin from sunlight.

Concluion

Overall, early and regular curcumin supplementation could be of protective benefit to maintain health in view of its comprehensive preventive and regenerative potential, especially for highly stressed competitive athletes, and we suggest that its integration into every­day life should be investigated.

References

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2. Csaki C, A. Mobasheri and Shakibaei M (2009). Synergistic chondroprotective effects of curcumin and resveratrol in human articular chondrocytes: inhibition of IL-1β-induced NF-kB-mediated inflammation and apoptosis. Arthritis Res & Ther. 11: R165.
3. Buhrmann C, A. Mobasheri, U. Matis, M. Shakibaei (2010). Curcumin mediated suppression of NF-kB promotes chondrogenic differentiation of mesenchymal stem cells in a high-density co-culture microenvironment. Arthritis Res & Ther, 12: R127
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6. Buhrmann C, A Brockmueller, A-L Mueller, P Shayan, M Shakibaei (2021). Curcumin Attenuates Environment-Derived Osteoarthritis by Sox9/NF-kB Signaling Axis. Int J Mol Sci. 22: 7645. doi: 10.3390/ijms22147645.
7. Cross, M.; Smith, E.; Hoy, D.; Nolte, S.; Ackerman, I.; Fransen, M.; Bridgett, L.; Williams, S.; Guillemin, F.; Hill, C.L.; et al. The global burden of hip and knee osteoarthritis: Estimates from the Global Burden of Disease 2010 study. Ann. Rheum. Dis. 2014, 73, 1323–1330.
8. Blanco, F.J.; Rego-Pérez, I. Editorial: Is it time for epigenetics in osteoarthritis? Arthritis Rheumatol. 2014, 66, 2324–2327.
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10. Henrotin Y, Malaise M, Wittoek R, et al. Bio-optimized Curcuma longa extract is efficient on knee osteoarthritis pain: a double-blind multicenter randomized placebo controlled three-arm study. Arthritis Res Ther 2019;21:179.
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Risk Factors 

Several anatomical, biomechanical and hormonal risk factors have been proposed over the years. From an anato­mical perspective, a smaller notch width or notch-width index, a smaller ACL volume, an increased tibial slope and general increased ligament laxity compared to male athletes have been associated with increased risk of sustaining an ACL injury [4 – 8]. Endogenous hormonal fluctuations during the menstrual cycle, specifically variations in the levels of oestrogen and relaxin during the follicular and ovulatory phases may increase ACL injury risk due to overall elevated ligament laxity [8 – 10]. Although there is some research into the association between oral contraceptives and a reduced ACL injury risk, currently there is not enough high-quality research demonstrating this relationship [8, 11, 12]. 

One of the typical non-contact ACL injury mechanism in female football is a change of direction combined with deceleration prior to sidestepping and landing from a jump [13, 14]. Biomechanically, several kinematic, kinetic and muscle activation patterns have been found to be related to increased risk of sustaining an ACL injury. Increased knee valgus angles at both initial contact and peak contact in landing, increased ipsilateral trunk motion combined with higher hip adduction angles, reduced knee flexion angles and limited hip flexion angles as well as increased tibial external and internal rotation angles are kinematic patterns that have all been found to be associated with higher ACL injury risk [13, 15 – 18]. In terms of kinetic para­meters, landing with a more extended knee position and erect posture at initial contact is associated with higher vertical ground reaction forces and thus increased ACL strain [13, 19 – 21]. Anterior tibial translation due to shear forces and increased external knee abduction moments combined with elevated internal rotation moments signifi­cantly contribute to ACL peak strain [13, 22]. 

Neuromuscularly, sex-specific differen­ces in muscle activation have been shown. Excessive quadriceps activation compared with insufficient hamstring co-­contraction in females may contribute to limited knee flexion angles upon landing, which may increase ACL strain. In contrast, increased hamstring co-­contraction prevents valgus stress on the knee, while gluteus maximus and medius activity reduces peak knee abduction angles and increases knee fle­xion angles upon landing [13, 23]. In female athletes, decreased activation of the vastus medialis compared to the vastus lateralis as well as decreased ­activation of the medial hamstrings compared to the lateral hamstrings have also been demonstrated. This medial-­to-lateral imbalance may explain why many females lack the ability to resist excessive abduction loads in the knee joint [13, 24].

Is the key professionalisation?

Sex disparities in access to training facilities and optimization of a crowded match calendar and travel may also play an important role in the risk of ACL injuries between males and females. Similarly, football boots, pitches quality, and football size and weight have been based on male, but not tailored around females’ characteristics [8]. 

Perhaps the most important extrinsic risk factor that exists in women’s football is the discrepancy in resources available. For example, there is a tangible gap in the quality of pitches between the women’s and men’s games. Due to poor availability of high-quality grass pitches, women are forced to play on either poor-quality surfaces or more recently, artificial turf, as seen during the 2015 FIFA Women’s World Cup [26, 27]. This is almost unheard of in the men’s game. Whilst these surfaces help mitigate cancellation of female events due to adverse weather conditions, the risk that it may pose to the female ACL is often overlooked. Indeed, findings of a recent meta-analysis published in the Orthopaedic Journal of Sports Medicine indicate that an increased risk of ACL secondary to match participation on artificial turf is only seen in female football players and not their male counterparts [28, 29].  

Additionally, female football boot technology is someway behind that seen in men’s boots. Females exhibit several intrinsic anatomical differences in foot structure that may place them at a biomechanical risk of ACL rupture. Although there is a lack of research supporting the relationship between boot choice and ACL rupture risk, recent research by the European Clubs Association has found that 80 % of female players playing in major European leagues report discomfort with their football boots. Although major football brands are making progress with their goals of better supporting the needs of female players [31], the avai­lability of female-tailored boots is poor, or at best, poorly advertised [26]. 

The discrepancy in resource availability is further highlighted by reduced accessibility to gyms to aid injury prevention programmes. This not only due to a lack of sufficient equipment within these gyms, but also the barrier to female participation underpinned by long-stan­ding issues such as gender-based norms dictated by society. It has been suggested that females have a lower training age considering the amount of time and exposure an athlete has had to structured, coached, and progressive training [8, 30]. Another key principle could be promotion of effective communication and collaboration within the wider club-­ecosystem. As part of the UEFA Women’s Elite Club Injury Study, Ekstrand et al found that risk factors for injury with the highest average importance were “lack of communication between medical staff and coaching staff” and “load on players” [32]. Although this was in the context of hamstring injuries, the same principles could be applied to ACL injuries. The medical team could collaborate directly with the sports science department to implement effective load management strategies on the same level like it is done in men’s football, and these to be communicated with the coaching staff to facilitate forward planning and implementation of such measures, including management of player’s match minutes and training schedules [33]. 

Can an ACL injury be predicted?

Jauhiainen et al. used an extensive screening test battery of 880 female elite athletes to investigate the predictive potential of multiple predictive machine learning methods on the risk of sustai­ning an ACL injury. Despite analysing a large prospective data set, the predictive ability was too low for ACL injury risk assessment in clinical practice. The reasons for the low predictive model might have been due to the failure to record training and match load data, including short term changes in physical variables and training loads. Therefore, further studies are needed to investigate what exact type of data and machine learning approaches should be used for more accurate injury prediction [25]. 

Conclusion

Over 20 years of research has failed to combat the disparity in the burden of ACL injuries between male and female footballers. Future work should look to define specific ACL risk reduction mea­sures and demonstrate how these might be implemented in the elite football setting. To do this, we should not focus only upon the specific intrinsic risk fac­tors in women footballers, but also on the environmental and psychosocially driven risk factors that currently exist [8, 33].

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Significant progress has been made in the field of injury prevention in football over the past three decades. Numerous research studies have been conducted, ranging from the sequence of research steps and the investigation of injury causes to the development and implementation of corresponding prevention programs. Van Mechelen et al. [1] developed a fundamental conceptual 4-step protocol for the prevention of sports injuries in 1992, which has since been further developed and adapted for many sports and injuries. Finch [2] expanded this model with two additional steps and formulated the TRIPP model, which aims to facilitate the transfer of research findings into injury prevention practice. Padua et al. [3] further supplemented this model with two additional steps focusing on the development and implementation of prevention programs. Meeuwisse [4] developed the dynamic, multifactorial model of the etiology of sports injuries to consider a variety of external and internal factors that can influence the risk of injury. To under­stand the injury-triggering event and the combination of factors that lead to an injury, Bahr & Krosshaug [5] developed a model that takes these events into account.

Using these models, multimodal injury prevention programs for the lower extremities have been developed. There is extensive evidence supporting the effectiveness of movement interventions in the form of neuromuscular training as a warm-up program to reduce football-related injuries in both genders, all age groups, and different skill levels. Examples of effective programs include the FIFA 11+ program [6], the Knee Control Program [7], and the Prevent Injury and Enhance Performance Program [8]. Specific selected exercises such as the Nordic Hamstring Curl (NHC) [9] or the Copenhagen Plank [10] also show a positive effect on reducing injuries. Despite the existence of evidence-based programs, there is often inadequate implementation in practice. This is often due to the required time commitment, associated costs, or lack of coaching staff. Careful adherence and consistent implementation by the coaching team also play a crucial role. Programs are often irregularly carried out or only parts or modified programs are applied. Reasons for this may include a lack of knowledge or insufficient experience in implementing and correctly executing these programs, as well as the complexity of the exercises [11].

8-Step Model 

In Figure 1, an 8-step model is presented that is intended to help better under­stand the various components and steps of a successful injury prevention system, starting from the identification of sport-specific requirements to knowledge transfer and program effectiveness assessment.

Individualization

A crucial factor for the success of injury prevention programs lies in the individual alignment during the development and implementation of corresponding measures. It is important to differentiate between primary, secondary, and tertiary prevention in the sports context. Primary prevention aims to prevent initial injuries. Secondary prevention involves the timely diagnosis and treatment of minor physical complaints or injuries with the goal of reducing severity. Tertiary prevention focuses on the rehabilitation of injuries with longer absence from training or competition and minimizing the risk of recurrent injuries [12].

When designing injury prevention programs, it is essential to differentiate between healthy players without injuries and players with injuries or a history of injuries. For athletes with previous injuries, it is important to identify specific risk factors that could lead to a recurrent injury. Additionally, potential neuromuscular and sensorimotor deficits that may have resulted from previous injuries should be considered. This can be done through written questionnaires, verbal interviews, or through assessments and screenings (e.g., FMS). Healthy athletes require a less conservative and more progressive approach. The prophylactic application of standardized prehab/­rehab protocols is usually not sufficient for them. Healthy athletes typically adapt more quickly to demands and require appropriate progressions to avoid plateaus. The intensity threshold and neuro­muscular challenge to achieve the desired adaptation will be higher in healthy athletes than in recently injured players. There may also be differences in motivation, as healthy athletes may be less intrinsically motivated to reduce pain and other symptoms compared to recently injured players. To ensure long-term compliance in healthy players, greater variation in exercises will be required to avoid training monotony.

Nutrition also plays an important role in the injury prevention process and should be adjusted accordingly. Proper nutrition not only helps supply the body’s energy stores and adjust to the demands of the sport but also supports the body’s natural healing and recovery processes. The physiological demands on athletes vary not only between different sports but also within a sport depending on position (e. g., goalkeeper vs. forward). Considering the individual weight goals of athletes, it is clear that generalized nutrition strategies are inadequate. These should be individually tailored based on actual training intensity, volume, and level to allow for precise alignment of energy intake and energy needs. Additionally, it is impor­tant to ensure adequate fluid intake before, during, and after training or a game. A fluid deficit at the start of a game can significantly impair performance and increase the risk of hyper­thermia [13].

Planning the Implementation of an Injury Prevention Program

The selection of exercises, training frequency, timing, intensity, and volume play a crucial role in the design and subsequent implementation of injury prevention programs. The programs should include various exercises in the areas of endurance, strength, plyometrics, speed, agility, and flexibility. In addition to these areas, prevention programs may include exercises to improve core stability, balance, and proprioception [14, 15]. An overall protective effect of endurance training is that athletes become more resilient to neuromuscular fatigue. This is particularly important as injuries often occur in the final phase of a game when athletes are already fatigued. Adequate strength training increases the load tolerance of the musculoskeletal system to the microtraumas that occur in training or games, leading to faster recovery. When selecting appropriate exercises in strength training, factors such as range of motion, speed of movement, and contraction form should be considered based on the respective injury mechanisms. A commonly used exercise, for example, is the Nordic Hamstring Curl (NHC). Eccentric training improves the muscle’s ability to absorb more energy before reaching muscle failure [16]. 

However, in this exercise, the proximally stressed muscles remain in a relatively constant position. Relevant hamstring injuries mainly occur during the terminal swing and early support phases of running. A suitable complement could be the Romanian Deadlift, as it also engages the proximal part of the hamstrings. Plyometric training not only improves explosive power but also has a preventive character. The focus should be on correct technique and mechanics in landing, jumping, and change of direction movements [17]. However, to prevent injuries, sport-specific and speed-oriented training is also required. A large portion of hamstring injuries occur during sprinting, so training at maximum speed should be given more attention. It is recommended to integrate sprint training at least once a week, reaching < 90 % of individual maximum speed [18].

As part of the training program, athletes should apply appropriate recovery strategies. Active recovery measures usually consist of aerobic training, which can be performed through various me­thods such as cycling, jogging, aqua jogging, or swimming. Active recovery is often seen as more beneficial compared to passive recovery due to improved blood flow and the elimination of metabolic waste products through increased oxygen supply. Among passive recovery methods, sleep is generally considered the most important factor. Inadequate sleep or poor sleep quality not only affect performance but also increase the risk of injury and negatively impact recovery after training or games. Athletes who sleep ≤ 7 hours per night over an extended period already have a 1.7 times higher risk of experiencing an injury compared to athletes who sleep ≥ 8 hours per night [19, 20].

Periodization

The integration of an injury prevention program into the weekly and daily training cycle can be a significant challenge but also offers many opportunities. Figure 2 illustrates a possible integration of injury prevention measures into a microcycle of one week. Prevention measures can be integrated into both the warm-up and cool-down, depending on the focus of the exercises or the training session [21]. An advantage of integrating into the warm-up or cool-down with the team is that the exercises are performed under the supervision of a coach, ensuring a higher quality of execution. Additionally, training takes place in a group setting and generally enhances athletes’ motivation. Likewise, appropriate prevention exercises can be integrated into the athletes’ individual strength training, where the coach may not be able to make corrections during execution. Integrating preventive exercises into the coach-supervised strength training could provide an additional opportunity to ensure the necessary individualization while maintaining high quality. Injury prevention training should ideally be conducted 2 – 3 times per week, preferably at the beginning and middle of the week. Performing isolated eccentric training at the end of the week could negatively impact game performance due to the regeneration time of up to 72 hours. Eccentric training on the day after the game results in significantly fewer microtraumas than performing it on the third day after the game [22].

Conclusion

Significant progress has been made in injury prevention research and application over the past 30 years. However, translating theoretical knowledge into practice remains a major challenge for all involved, yet it also presents one of the most promising opportunities for the future of football medicine. To successfully integrate injury prevention into clubs and teams, a systematic approach and a comprehensive understanding of each step are required. Further research, particularly on parameters such as exercise selection, volume, intensity, and periodization, is necessary to adapt programs to different contexts. Established programs that already exist and have been successfully tested can be easily implemented by amateur teams with limited training time. Professional teams, on the other hand, require a variety of evidence-based exercises with appropriate progressions and variations. Injury prevention should not be viewed in isolation from performance enhancement, as they are closely linked. The foundation for this should be individualization, distinguishing between athletes with or without a history of injury. The success of injury prevention programs depends on regular implemen­tation. Therefore, measures to reduce injuries should be an integral part of football training. This, in turn, requires a high level of willingness to implement on the part of the players, coaching staff, and the club.

Literature

[1] Van Mechelen, W., Hlobil, H., & Kemper, H. C. G. (1992). Incidence, Severity, Aetiology and Prevention of Sports Injuries: A Review of Concepts. Sports Medicine, 14(2), 82–99.

[2] Finch, C. (2006). A new framework for research leading to sports injury prevention. Journal of Science and Medicine in Sport, 9(1–2), 3–9.

[3] Padua, D. A., Frank, B., Donaldson, A., De La Motte, S., Cameron, K. L., Beutler, A. I., DiStefano, L. J., & Marshall, S. W. (2014). Seven Steps for Developing and Implementing a Preventive Training Program. Clinics in Sports Medicine, 33(4), 615–632.

[4] Meeuwisse, W. H. (1994). Assessing Causation in Sport Injury: A Multifactorial Model. Clinical Journal of Sport Medicine, 4(3), 166–170.

[5] Bahr, R., & Krosshaug, T. (2005). Understanding injury mechanisms: A key component of preventing injuries in sport. British Journal of Sports Medicine, 39(6), 324–329.

[6] Thorborg, K., Krommes, K. K., Esteve, E., Clausen, M. B., Bartels, E. M., & Rathleff, M. S. (2017). Effect of specific exercise-based football injury prevention programmes on the overall injury rate in football: A systematic review and meta-analysis of the FIFA 11 and 11+ programmes. British Journal of Sports Medicine, 51(7), 562–571.

[7] Walden, M., Atroshi, I., Magnusson, H., Wagner, P., & Hagglund, M. (2012). Prevention of acute knee injuries in adolescent female football players: Cluster randomised controlled trial. BMJ, 344(may03 1), e3042–e3042.

[8] Gilchrist, J., Mandelbaum, B. R., Melancon, H., Ryan, G. W., Silvers, H. J., Griffin, L. Y., Watanabe, D. S., Dick, R. W., & Dvorak, J. (2008). A Randomized Controlled Trial to Prevent Noncontact Anterior Cruciate Ligament Injury in Female Collegiate Soccer Players. The American Journal of Sports Medicine, 36(8), 1476–1483.

[9] Petersen, J., Thorborg, K., Nielsen, M. B., Budtz-Jørgensen, E., & Hölmich, P. (2011). Preventive Effect of Eccentric Training on Acute Hamstring Injuries in Men’s Soccer: A Cluster-Randomized Controlled Trial. The American Journal of Sports Medicine, 39(11), 2296–2303.

[10] Harøy, J., Clarsen, B., Wiger, E. G., Øyen, M. G., Serner, A., Thorborg, K., Hölmich, P., Andersen, T. E., & Bahr, R. (2019). The Adductor Strengthening Programme prevents groin problems among male football players: A cluster-randomised controlled trial. British Journal of Sports Medicine, 53(3), 150–157.

[11] Minnig, M. C., Hawkinson, L., Root, H. J., Driban, J., DiStefano, L. J., Callahan, L., Ambrose, K. R., Spang, J. T., & Golightly, Y. M. (2022). Barriers and facilitators to the adoption and implementation of evidence-based injury prevention training programmes: A narrative review. BMJ Open Sport & Exercise Medicine, 8(3), e001374.

[12] Kisner, C., & Colby, L. A. (2012). Therapeutic exercise: Foundations and techniques (6th ed). F.A. Davis.

[13] Belval, L. N., Hosokawa, Y., Casa, D. J., Adams, W. M., Armstrong, L. E., Baker, L. B., Burke, L., Cheuvront, S., Chiampas, G., González-Alonso, J., Huggins, R. A., Kavouras, S. A., Lee, E. C., McDermott, B. P., Miller, K., Schlader, Z., Sims, S., Stearns, R. L., Troyanos, C., & Wingo, J. (2019). Practical Hydration Solutions for Sports. Nutrients, 11(7), 1550.

[14] Gallucci, J. (2014). Soccer injury prevention and treatment: A guide to optimal performance for players, parents and coaches. Demos Medical Publishing, LLC.

[15] Meyer, T., Faude, O., & Funten, K. A. der. (2015). Sports medicine for football: Insight from professional football for all levels of play. Meyer & Meyer Sport.

[16] LaStayo, P. C., Woolf, J. M., Lewek, M. D., Snyder-Mackler, L., Reich, T., & Lindstedt, S. L. (2003). Eccentric Muscle Contractions: Their Contribution to Injury, Prevention, Rehabilitation, and Sport. Journal of Orthopaedic & Sports Physical Therapy, 33(10), 557–571.

[17] Bahr, R., & Engebretsen, L. (2009). Sports injury prevention. Wiley-Blackwell.

[18] Edouard, P., Mendiguchia, J., Guex, K., Lahti, J., Prince, C., Samozino, P., & Morin, J.-B. (2023). Sprinting: A key piece of the hamstring injury risk management puzzle. British Journal of Sports Medicine, 57(1), 4–6.

[19] Milewski, M. D., Skaggs, D. L., Bishop, G. A., Pace, J. L., Ibrahim, D. A., Wren, T. A. L., & Barzdukas, A. (2014). Chronic Lack of Sleep is Associated With Increased Sports Injuries in Adolescent Athletes. Journal of Pediatric Orthopaedics, 34(2), 129–133.

[20] Huang, K., & Ihm, J. (2021). Sleep and Injury Risk. Current Sports Medicine Reports, 20(6), 286–290.

[21] Small, K., McNaughton, L., Greig, M., & Lovell, R. (2009). Effect of Timing of Eccentric Hamstring Strengthening Exercises During Soccer Training: Implications for Muscle Fatigability. Journal of Strength and Conditioning Research, 23(4), 1077–1083.

[22] Lovell, R., Whalan, M., Marshall, P. W. M., Sampson, J. A., Siegler, J. C., & Buchheit, M. (2018). Scheduling of eccentric lower limb injury prevention exercises during the soccer micro‐cycle: Which day of the week? Scandinavian Journal of Medicine & Science in Sports, 28(10), 2216–2225.

Case History

On 10 December 2023, I sustained a type 3b myofascial injury to my left gluteus medius muscle when doing a turn-and-shoot move as an assistant coach during my nine-year-old son’s football training session. Immediately after the injury, I was initially incapable of even standing and was indeed unstable on my left leg during lateral stabilisation movements. At first even walking was not possible without help as I had developed a Trendelenburg walking pattern. Immediately after the injury, I could unfortunately only apply ice and cold-water baths (8° Celsius) for analgesia and for reducing the bleeding, and “elevate” as best I could; proper compression was not possible at this point and would certainly have been too painful. On the evening of the accident, it was impossible for me to lift my left leg sideways (in the sense of abducting the hip) while in the right lateral position due to the severe pain, which really worried me. A left-lateral position for the purpose of compression was also out of the question. An enormous haematoma developed at the base of the iliac crest within two days.

Clinical Examination findings prior to initial treatment on 11.12.2023

Pain on pressure, stretching and tensing pain in the entire region of the gluteus medius and over the entire left side of the iliac crest, anteriorly and laterally. There was also numbness of the skin over the gluteus medius immediately after the injury. Positive Trendelenburg gait pattern on the affected left side. Abduction of the left hip was not possible in the right lateral position and very significantly restricted when standing. VAS at rest 5 points, on loading 8 – 9!

MRT on 11.12.2023

• extensive myofascial oedema (just over 9 mm) with haemorrhages from the proximal gluteus medius muscle (series 8 image 26, series 7 image 26) associated with partially amorphous and partially absent visualisation of the muscle fascia
• focal detachment (5 mm) of the gluteal fascia from the iliac crest
• partial, fascial avulsion of the muscle fascicles with an elongated wavy appearance (series 3 image 14).

Most likely, the following treatment would normally be initiated in a case with such severe pain, severe haematoma, and oedema as well as massive functional impairment of the injured muscles: NSAIDs for two to three weeks for pain management, continued cooling with ice packs in the usual manner plus manual lymphatic drainage by a physio­t­herapist, physical rest, possibly non-weight bearing on forearm crutches due to the instability (in which case, possibly even injections for thrombosis prevention). Later, pain adapted increase of load, assisted by a physiotherapist.

Treatment

Despite the severe pain, I refrained from taking painkillers (NSAIDs) because I am absolutely convinced of the scientifically

proven effect of NSAIDs in reducing tendon and muscle healing, and I did not want this for myself in such a situation. On establishing the diagnosis by MRI and excluding any indication for surgery, I opted for the following combination of conservative, regenerative treatment which was performed daily from 11.12. until 19.12.23 by my clinic team (whom I would like to thank from the bottom of my heart!!! You are simply great!!!):

High-power laser (DolorClast High Power Laser, Power Laser, 300 W, Electro Medical Systems, Nyon, Switzerland): Daily anti-­inflammatory treatment at three adjacent sites in the area of injury, each for 5 minutes (i.e. a total of 15 minutes per session)

Therapeutic nuclear magnetic reso­nance (MBST (molecular biophysical stimulation therapy), Medtech, Arthro Spin Flex, treatment chip card for 7 tendon sessions): A total of 7 sessions of 60 minutes each with a tendon-­torso chip card, once daily.

Radial shock wave therapy (Swiss DolorClast, (Swiss DolorClast, radial shock waves, Electro Medical Systems, Nyon, Switzerland): rESWT in the region of the injury and with increasing application pressure to the maximum tolerable pain limit and application until the pain is noticeably reduced (approx. 10,000 impulses, 25 Hz, 40-mm and 20-mm applicator)

Neuroreflectory hyperbaric CO2 cryotherapy (Cryolight, ELMAKO, Iffezheim, DE): The whole of the affected, swollen and painful region of the gluteus medius extending to the entire iliac crest; 3 x cooled down to 0 – 4 degrees

As early and as much movement as possible (whatever the pain allows within the tolerable range!). Autonomous athletic training to stabilise and promote control.

Anti-inflammatory combination comprising Insumed PhytoShake 1 x daily 10 g, Traumeel 6 x 2 tabs. and Wobenzym 3 x 3 tabs. during the entire treatment period.

We know from treating a large number of patients for the same or similar indications that the combination of these forms of therapy for muscle or tendon injuries has very often led to rapid relief of pain and better and faster regeneration than usual. Descriptions of the combined use of all of the above treatment methods for this type of clinical picture and, above all, with this severity are, of course, not available in the literature to date. High-energy laser was always applied directly before the MBST and therefore 60 minutes before the ESWT treatment as indicated above, as it has been proved scientifically that laser produces pain relief (reaching its peak after approx. 60 minutes), which means that significantly higher working pressures are then tolerated during the subsequent radial ESWT, rendering this therapy even more efficient. In my experience, this rapid pain-relieving effect also applies to MBST, which meant that the working pressure during ESWT could be increased very quickly and very strongly. Although pressures of only around 1.3 to 1.6 bars were possible on the 1st day of treatment, we were already able to apply 3.0 bar on the 2^nd day and even 4.0 bar on the 3^rd day using the large 40-mm applicator. From the 4^th day on, this was even easily possible with the 20-mm applicator. However, much more important to me than pain relief was the well-known tissue-regene­rating effect of MBST, which I have observed countless times in my own patients. Added to this is the synergism of the three forms of therapy, as laser (applied directly after injury) not only reduces oxygen radicals in the injured tissue and thus has an anti-inflammatory and anti-oedematous effect, but also inhibits collagen remodelling in the injured muscle and thus counteracts rapid scarring. This, in combination with the clearly scientifically proven, strong muscle-regenerating effect of radial shock wave therapy and also MBST, results in a perfect combination for muscle and tendon injuries. Hyperbaric CO2 cryotherapy was applied to the treated region three times after each session up to a temperature of 0 to 4 ° Celsius. It results in a rapid restoration of the semi-permeability of the cell membranes after injury and has an anti-­inflammatory and very rapid pain-relieving effect. The injured muscles were trained as early as possible with abduction exercises, walking training, and stabilisation exercises from the first day of treatment with a rapid increase in intensity.

Clinical Course

These measures led to a very rapid improvement of the symptoms. Even after the 3rd treatment session, that is, on the 3rd day after the injury, I was able to fully abduct the left hip almost without pain while lying in the right lateral position and walk with such a feeling of stability that I was able to fully return to work. On the 4th day, I was already able to walk normally and without pain again, and on the 5th day do one-legged squats and stabilisation exercises. Jogging was possible on the 6th day, and on the 7th day I could sprint upstairs without any problems. As an assistant coach in my son’s football team, I was also able to pass balls to the players again while warming up before a tournament. On the 10th day, I was able to jump with both legs and land one-legged on the affected leg as well as jog 3 km at speed without pain and with full stability.

By the 11th day I was already able to participate in my son’s training sessions again. On the 15th day, I was able to play football with the adults’ team again and felt stable and completely free of pain.

MRI FOLLOW-UP ON 22.12.2023 (11th DAY AFTER INJURY)

MRI follow-up 22.12.2023 (11th day after injury)

• The myofascial contours are more clearly defined. Partial demasking of well-circumscribed myofascial seromas without space-occupying effect (series 8 image 27 and series 7 image 27; previous scan series 8 image 26 and series 7 image 26).
• Today the avulsion from the iliac crest is no longer evident
• The previously documented elongated muscle fascicles once again show a more defined course with contact to the partially more distinct muscle fascia. (series 3 image 16 as compared with series 3 image 14 of the previous scan).

It should be noted here that the result of the MRI follow-up examination on completion of the combination therapy usually does not quite reflect the actual clinical course. In our experience, however, this is not necessary either. We always concentrate on the clinical course and not just on the MRI scan. In our view, too much emphasis is placed in sports medicine, and especially in professional sports, on complete recovery as shown on the MRI scan, which is, however, not necessary. In our experience, there is definitely no higher re-injury rate if you are guided by the clinical course, ultrasound follow-up examinations and, for example, EMG measurements of the affected muscles.

Conclusion

The combination of high-energy laser therapy, rESWT, MBST, hyperbaric CO2 cryotherapy, anti-inflammatory therapy comprising phyto-pharmaceuticals and enzyme therapy as well as early athletic training can achieve a very satisfactory and rapid result with weightbearing stability, associated with freedom from pain and the return to sport, even in the presence of such marked findings.

Future Prospects

In the future, the combination therapy described here or – if not all the components are available – at least some of them should, in my view, play an important role in the treatment of muscle injuries in both professional and amateur athletes. Unfortunately, the ama­zing regeneration potential with regard to the much faster healing of muscle, tendon and ligament injuries, the lower re-injury rate, as well as the prevention prospects, especially for muscle injuries, do not yet seem to have found their place in general sports medicine or orthopaedics, and unfortunately not in many areas of professional sports either. We are trying to change this via the “sportärztezeitung” network – for all those who are prepared to think outside the box. I really like this form of treatment; we have enjoyed incredible success for our patients, and now it has even saved me weeks, if not months, of problems myself.

I would like to draw two things to the attention of all colleagues who are interested:

1.“thesportgroup academy’s” guided education training courses – face-to-face or online! The upcoming dates can be found here…

2. The importance of workplace training in the field of sports medicine: We have in no way exhausted the conservative therapeutic options of modern treatment and prevention. Even though the realities of healthcare in our medical system and the individual patient’s actual situa­tion always have to be taken into account of course, our aim is to develop new standards for better sports medicine together with our colleagues and in collaboration with the “sportärztezeitung.”

Video documentation of the case 

INPUT FROM A RADIOLOGIST…

In the diagnostic work-up of acute muscular injuries, MRI has the advantage over high-resolution ultrasound of showing the anatomy of the involved, but also non-injured, neighbouring structures more clearly. This applies to primary diagnostics, but also especially for the follow-up examinations. The severity of the injury, which is so important for the prognosis, but also its relationship to the biomechanical transmission chains (myofascial, myotendinous, purely muscular or combined) can be well documented. In the acute phase of the injury, however, MRI may overestimate the muscle injury due to the extensive oedema and haematoma. Here, image quality with a resolution that does justice to muscle anatomy is of crucial importance for the correct diagnosis! In the present case, myofascial injury to the gluteus medius muscle was clearly documented and was distinguishable from oedema and haematoma. The follow-up scan after 11 days already showed the reparative processes with fibrotic reorganisation of the fascia and re-attachment of the traumatic myofascial separation of the muscle fascicles. This is particularly well illustrated by the straighter course of the muscle fascicles, which had initially retracted after the injury and had demonstrated an elongated wavy course. This case well illustrates the rapid recovery capacity of an injured muscle.

Dr. med. Peter Mundinger, is a Consultant for Diagnostic Radiology, with an additional qualification in Neuroradiology and is also a specialist for musculoskeletal imaging studies / Private practice for radiology H15

INPUT FROM AN ORTHOPAEDIC SURGEON…

Actionism? Yes, but with common sense: In today’s sports medicine landscape, so highly pressured to achieve recovery, it is common to aspirate these injuries, infiltrate PRP (platelet rich plasma), administer Actovegin, local anaesthetics, Traumeel or similar medi­cations, and get out the forearm crutches for 7 days. Peter impressively demonstrates that it is also possible to successfully treat a serious muscle injury very quickly without invasive mea­sures. Apart from appropriately coordi­nated physical measures to modulate inflammation and healing, early pain-­adapted mobilisation and avoidance of NSAIDs also appear to have made a significant contribution towards the successful outcome. It is particularly worth mentioning the MRI diagnostic workup during the course of management. This made it possible to reproduce the structural changes which developed after the multimodal therapy. This is what we need for the future of sports medicine. As said in the radio­logical commentary – “This case well illustrates the rapid recovery capacity of an injured muscle” – we and Peter Stiller were able to exert a significant positive effect on this with the therapy and nutrition (!) mentioned.

It is exciting to see that, despite our inclination towards invasive treatment methods, we can also act “differently” in a promising way and thus set an impressive example for physical mea­sures in sports care.

Dr. med. Alberto Schek, is a Consultant for Trauma and Orthopaedic Surgery with additional qualifications in Special Orthopaedic Surgery, Sports Medicine and Manual Medicine with a diploma in Sports Osteopathy / Paracelsus Sports Medicine & Prevention Bremen