ROBERT BIELITZKI, TOM BEHRENDT, PROF. LUTZ SCHEGA / DEPARTMENT OF SPORT SCIENCE, OTTO-VON-GUERICKE UNIVERSITY MAGDEBURG

PROF. MICHAEL BEHRINGER MD / DEPARTMENT OF SPORTS SCIENCES, GOETHE UNIVERSITY FRANKFURT

ALEXANDER FRANZ MD / DEPARTMENT OF ORTHOPEDICS AND TRAUMA SURGERY, UNIVERSITY HOSPITAL BONN 

Acute severe injuries and degenerative diseases of the musculoskeletal system as well as surgical interventions are usually characterized by phases of restricted mobility with strongly reduced load-bearing capacity or complete immobility of corresponding areas [1]. This temporary or long-lasting situations are strongly associated with strength loss due to neural impairments (e.g., decline in high threshold motor unit recruitment and arthrogenic inhibition [2, 3]) and muscle atrophy (due to an imbalance in muscle protein synthesis and breakdown [3, 4]). 

In the recent past, a new conservative therapy approach termed blood flow restriction (BFR) has gained great inte­rest from scientists and therapists. BFR training describes an alternative me­thod based on partial vascular occlusion to induce metabolic changes that allow mitigating functional and morpho­lo­gical degeneration or increasing muscle mass and strength by using no additional activities [5] or low mechanical loads [6], respectively. Considering these be­neficial effects, BFR seems sui­table after acute injuries (e.g., anterior cruciate ligament rupture) as well as for patients with degenerative diseases (e.g., gon­arthrosis) or after a surgical intervention (e.g., total knee arthroplasty). 

Mechanisms of BFR-induced effects on muscular adaptations and pain management

BFR is characterized by the application of pneumatic cuffs to the proximal part of a limb to decrease arterial and block venous blood flow [7]. Venous blood pooling is thought to increase metabolic stress due to a change in energy meta­bolism in favor of anaerobic processes and accumulating metabolites [8, 9], which accelerates muscle fatigue deve­lopment [10]. In this regard, invasive catheter studies demonstrated that low-load resistance exercise under venous occlusion causes hypoxemia in the exercising limb [11]. Further occurring mechanisms (e.g., increased type II muscle fiber recruitment and cell swelling) are assumed to trigger signal cascades which increase protein synthesis and thus, induce muscle hypertrophy [8, 9]. In addition, BFR is able to reduce pain due to provoking hypoalgetic effects [12]. Considering the current evidence, BFR-induced hypoalgesia is probably caused by a conditioned pain modulation [13] (i.e., diffuse noxious inhibi­tory control-like effect [14] or “pain inhibits pain” [15]) where a reduction in pain perception is evoked by another hetero­topically applied noxious stimulus [16]. Another possible mecha­nism is the activation of the endo­genous opioid and endocannabinoid systems due to stimu­lation of group III and IV afferents leading to the production of specific neurotransmitters, which modulate the sensitivity of nociceptors [17, 18]. 

BFR in clinical practice in phases of immobilization or severely restricted mobility

Preoperative treatment of degenerative diseases and/or elective surgery

Considering the main benefits of BFR training, inducing significant adap­tations in the muscular system with the associated ability to reduce pain, its application in the medical field is of particular interest. Joint arthrosis is one of the major diseases affecting the ske­letal system, leading to severe reductions in mobility as well as in skeletal muscle mass and strength [19, 20]. Total joint replacement (e.g., total knee arthroplasty, TKA) is often the last option to maintain or restore mobility. However, the surgery itself and early postoperative immobilization usually causes further progression of muscular atrophy and strength loss [21]. Therefore, an improvement in patients’ functional and morphological resources before elective surgeries such as TKA is a strong predictor for a better postoperative outcome [22, 23]. While previous attempts about prehabilitation (i.e., exercise programs prior to a surgery) showed too small and/ or only short-term effects in improving postoperative function and reducing pain after joint replacement surgery [24], BFR could provide a decisive new alternative to create a favo­rable functional and morphological environment before surgery. Prehabi­litative treatment with BFR training has already been shown to have a major impact on pre- and postoperative muscle mass, strength and function in patients receiving elective TKA [25] or abdo­minal surgery [26].

Postoperative treatment or conservative rehabilitation

In the early postoperative period, especially during complete immobilization, BFR can be used passively (i.e., without additional exercise) to counteract the injury/ surgery-induced loss of muscle mass [27], strength [28, 29], and to reduce local pain [30]. If possible, resis­tance exercises with very low loads can be performed during phases of limited mobility. It has been shown that low-load BFR training induces similar increases in muscle mass to high-load [6] and low-load training performed until exhaustion [31]. In this regard, especially low-load BFR training might be a convenient option as high mechanical stress of high-load training is avoided and cumulative low mechanical stress of low-load training until exhaustion is reduced (i.e., due to lower total work) [32]. Furthermore, Korakakis et al. have shown that BFR combined with low load knee extension exercise not only reduced anterior knee pain but also allowed the patients tolerate higher mechanical loads in subsequent therapy sessions [14, 33] which, in turn, favors gains in muscle strength. Therefore, Bielitzki et al. proposed that an early integration of BFR potentially accele­rates the recovery process compared to traditional care [32]. 

Safety information

Generally, there is no increased risk of adverse health events when performing BFR training [34]. Apart from side effects of traditional exercise/ training (e.g., muscle damage/ soreness), the most common adverse events are tingling sensations in distal extremities (71.2 %), hematomas (4.8 – 13.1 %), and numbness (1.3 – 26.9 %). In few cases, serious side effects such as rhabdomyo­lysis (0.01 – 1.9 %) or venous thrombus formation (0.06 %) may occur [35, 36]. However, BFR exercise may cause an increased response of the metabolic and cardiovascular systems (lactic acidosis, venous hypertension) [37, 38]. To mini­mize the risk of adverse health events, patients should be screened for possible contraindications (Table 1). However, if used appropriately, BFR can also be applied in critically ill patients (e.g., patients with chronic kidney [39] or cardiovascular disease [40]).  

Recommendations for application during strongly reduced load capacity

Considering the current recommen­dations, Table 2 provides guidance for the proper application of BFR training during immobilization and strongly limited mobility with very low-load tolerance with the goal of optimizing training efficacy and patient safety [34]. Especially in these phases, it seems nece­ssary to set an adequate high level of cuff pressure in order to induce beneficial effects. For example, Mouser et al. have shown that only high pressures combined with very low-load resistance training induced beneficial vascular adaptations similar to high-load resis­tance training [41]. Furthermore, the studies by Hughes et al. demonstrated that high pressures are more likely to induce hypoalgetic effects than low pressures combined with low-load resistance and aerobic exercise [17, 18].

Conclusion

Considering the current evidence on muscle mass and strength in clinical populations [42, 43], BFR provides a promising method for patients especially during immobility or periods of strongly reduced mobility with very low mechanical resilience. While a preoperative treatment can create a protective effect on the surgical limb to reduce post-surgical strength loss and muscle atrophy [3], post-injured / post-surgical therapy can be supported by the application of BFR, either passive or combined with very low-load exercises, to regain pre-traumatic / presurgical strength level faster compared without using BFR [32]. 

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The recently published paper from Ekstrand et al. describes the incidence of hamstring injuries in male professional football players over consecutive 21 seasons (2001/02 to 2021/22). The authors also analyse the time trends of hamstring muscle injuries over the most recent eight seasons (2014/15 to 2021/22) and in addition, they outline hamstring injury location, mechanism and recurrence rate. 

Data was collected from the Elite Club Injury Study (ECIS). The individual player exposure and the time-loss in­juries of 3909 players were recorded by the medical staff of 54 football teams from 20 European countries, which all qualified for the UEFA Champions League (UCL) group stage. 

A hamstring injury was defined as a ’complaint sustained by a player that resulted from a football match or football training and led to the player being unable to take full part in future football training or match play‘. In the beginning injuries were solely classified by using the Orchard Sports Injury Classification System (OSICS); however, since 2011/12 the Munich Muscle Injury Classification was also used to classify hamstring injuries. Between 2001/02 and 2021/22, 2636 hamstring injuries were documented representing 19 % of all reported injuries. Compared to the first recorded season, the proportion of diagnosed hamstring injuries and the proportion of all injury absence days caused by hamstring injuries have doubled by 2021/22 (from 12 % to 24 % and from 10 % to 20 % respectively). Speci­fically during the last 8 consecutive seasons the incidence (Number of injuries per 1000 player hours, 6,7 % annually) and the burden (Number of lay-off days per 1000 player hours, 9.0 % annually) of hamstring injuries during training and match play have increased significantly. The hamstring injury incidence was 10 times higher during match play than during training and the median lay-off following a hamstring injury was 13 days. Overall it was reported that during a season 20 % of players missed training or match play due to a hamstring injury and 8 hamstring injuries can be expected in a 25-player squad per season. In addition, there were more structural than functional injuries classified, whereby these structural injuries were associated with a longer lay-off time than the functional ones (median absence 17 vs. 6 days). 

In terms of the injury mechanism and location, this study confirmed the existing knowledge that sprinting was the most common mechanism and the biceps femoris injuries were more frequent than semitendinosus and semimembranosus injuries. However, further details concerning which phase of sprinting (i.e., terminal swing, early stance) or which exact part of the biceps femoris (i.e., proximal, distal, T-junction, long/short head or myofascial, myotendinous, or tendinous) were not described. Regarding the recurrence rate, 18 % of all recorded hamstring injuries were recurrences, from which early recurrences (within 2 months) made up 69 %. Recurrences were nine times more likely to occur in matches than in training. An increased recurrence rate specifically within the first 2 months could indicate that return to full training/competition may be too early for some types of injuries. Taking into consideration that the healing time of different kind of tissues takes longer than others (i.e., connective tissue), healing may not be sufficiently completed to sustain certain thresholds of high-speed exposure. The authors hypothesize that the reason for the increasing number of hamstring injuries could be because the intensity of elite’s football matches has significantly increased, which has led to more high intensity activities in professional footballers compared to the past. Another explanation may be related to a more crowded match calendar of players associated with fewer training sessions during the (pre-) season period considering that more training sessions may lower the injury risk. In summary, this publication highlights the increa­sing burden of hamstring injuries in elite football. More effort is needed to understand better how to prevent the first injury and how to manage injured players more effectively to reduce the risk of re-injuries. 

With the infrared thermography we use (FLIR E75 thermal imaging camera, Fig. 1) the camera displays more than 75,000 measured positions with a thermal sensitivity of <0.04 degrees tempe­rature difference, and thus it can reliably demonstrate even small areas of hyperaemia (trigger points).  We can differentiate between active myofascial trigger points which are often extremely painful and frequently weaken the affected muscle, latent myofascial trigger points which are only painful on movement, and associated trigger points which ­develop due to functional disorders of neighbouring muscle groups. More recently, differentiated EMG investi­gations are being used increasingly in conjunction with thermography to identify problems with efferent signals to the musculature in parallel, and to correct these with the help of biofeedback training. Initially thermography was mainly used for muscles close to the vertebral column to identify painful muscular tension in the lumbar and cervical spine and to work specifically on these structures. In the present case the indication for diagnostic thermo­graphy has been extended to Achilles tendon symptoms.

Case study 

We were consulted by a 29-year-old [female] patient with recurrent symptoms at the myotendinous junction of the right Achilles tendon, particularly one day after sporting activity (running). Her average training schedule was 40 – 50 km/week, she could not remember having had an accident.  The diagnostic imaging we performed (ultrasound, MRI) and differentiated foot pressure measurements ruled out any structural changes in the tendon and any relevant foot deformities. Only the ultrasonography on the day after spor­ting activity showed peritendinitis in the proximal part of the tendon. The subsequent EMG of the gastrocnemius muscle showed an increased resting tone of the right gastrocnemius. Further functional diagnostics (neuromuscular activation) showed a reduced efferent supply to the medial calf muscles (Figs. 2 & 3). 

The thermography carried out in pa­rallel impressively showed a painful area in the proximal region of the right Achilles tendon (Figs. 4 & 5). In addition to (focused) shockwave therapy the patient was treated with laser therapy and neuroreflex cryotherapy of the proximal Achilles tendon origin with taping of the muscle and (later) adjunctive biofeedback training of the calf muscles (Figs. 6 – 10).

The follow-up examinations showed a marked reduction in trigger point formation over the proximal Achilles tendon, even after the first treatment session. After two sessions of shockwave therapy plus taping and two sessions of biofeedback training the patient was clinically 100% symptom-free (Figs. 11 – 13).

Summary

Thermography impressively helps diagnose muscular trigger points and moni­tor successful treatment, particularly of functional symptoms, including those in the tendinous origins distant from the spine. Secondary muscle dysfunction is demonstrated by EMG and treated ­using EMG-based biofeedback therapy.

To this end the current scientific litera­ture was analysed and combined with expert opinion to formulate informative statements on the use of PRP. We used a precise methodical procedure based on a modified Delphi process (scientific adviser Philippe Beaufils, France). Under the leadership of Laura de Girolamo (Italy) and Lior Laver (Israel) a steering group (12 specialists from 9 European countries) formulated questions and answers based on the literature search on the subject areas 1) PRP – Rationale and Indication, 2) PRP – Preparation and Characterisation, and 3) PRP – Protocol. The questions were then eva­luated in a two-stage process by another rating group (22 specialists) until consensus was reached. In the concluding stage a third group reviewed the geographic adaptation to the various European countries. After this complex process a total of 28 questions and answers, including an overview of the literature, were drawn up. The discussions included questions such as the dependence on the degree of osteoarthritis, the age of the patients, use during the inflammatory phase, preventive use, a comparison with corticosteroids or hyaluronic acid, the superiority of leucocyte-rich or leucocyte-poor PRP, and many others. The original version of the most important statement on the clinical evidence on the use of PRP is cited here.

QUESTION 1: Does current clinical evidence support the use of PRP for knee OA?

Does current clinical evidence support the use of PRP for knee OA?

Statement: Clinical evidence confirms the efficacy of PRP in the treatment of knee osteoarthritis (OA). Level I and II clinical studies, as well as additional prospective studies, support the safety and clinical benefit of PRP for knee OA, which was shown in comparison to both placebo (saline) and control treatments such as hyaluronic acid or corticosteroids (CS). The efficacy of PRP in the treatment of knee OA has been also supported by meta-analyses and confirms the findings of preclinical research. The consensus group can therefore conclude that there is enough preclinical and clinical evidence to recommend/support the use of PRP in knee OA (see following questions addressing PRP specifications and in­dications).

The answer is based on 5 meta-analyses, one RCT, and one systematic review. The complete consensus can be downloaded free of charge from the homepage of the ESSKA.

Chairpersons: Laura de Girolamo, Lior Laver

STEERING AND LITERATURE GROUP MEMBERS: Philippe Beaufils (France) – ESSKA Consensus Projects Advisor, Mikel Sanchez (Spain), Giuseppe Filardo (Italy), Ramon Cugat (Spain), Thomas Tischer (Germany), Jeremy Magalon (France), Rodica Marinescu (Romania), Marko Ostojic (Bosnia), Ferran Abat (Spain), Elizaveta Kon (Italy), Ricardo Bastos (Portugal), Baris Kocaoglu (Turkey), Michael Iosifidis (Greece)

To date, the principles of action of ESWT are poorly understood and the success of therapy frequently lacks ade­quate pathophysiological explanation. Numerous studies on different mechanisms of action have now been published, but there is a deficiency of scientific consensus on the effects in the respective indications of ESWT. The aim of our research group was to develop a concept on the biophysical effects of ESWT on musculoskeletal tissue based on current scientific knowledge. 

Methods

We performed a Systematic Review in the literature databases “PubMed” as well as “Web of Science” with the keywords “shock wave OR shock waves OR shockwave OR shockwaves NOT urol* NOT stone NOT review NOT clinical trial” at the cutoff date of September 30, 2021 according to the PRISMA guidelines. By reading the titles and abstracts of the papers, relevant basic science studies on mechanisms of action of ESWT were identified. In the systematic review, 181 different trials were divided into three different groups and then analyzed. The groups referred to the effect of the diffe­rent target tissues of ESWT: “cartilage and bone” (100 included studies), “muscle / nerve tissue” (42 included studies) and “connective tissue” (39 included studies). 

Results

Analysis of the studies reviewed showed heterogeneity of studies with numerous changes at the cellular level due to shock wave therapy. Ultimately, 10 key messages could be formulated through our systematic analysis: (1) Compared to the effects of many other forms of the­rapy, the clinical benefit of extracorpo­real shock wave therapy does not appear to be based on a single mechanism. (2) Different tissues respond to the same mechanical stimulus in different ways. (3) Just because a mechanism of action of extracorporeal shock wave therapy was described in a study does not automatically mean that this mechanism was relevant to the observed clinical effect. (4) Focused and radial extracorporeal shock wave therapy seem to act in a similar way. (5) Extracorporeal shock wave therapy stimulates both progenitor and differentiated cells, and has posi­tive effects on pathologies of bone and cartilage. (6) Extracorporeal shock wave therapy apparently mimics the effect of capsaicin by reducing substance-P concentration. (7) Extracorporeal shock wave therapy apparently mimics effects of injection of Botulinum toxin A by destroying endplates in the neuromuscular junction. (8) Extracorporeal shock wave therapy apparently imitates certain mechanisms of action of neural therapy. (9) Extracorporeal shock wave therapy apparently imitates certain mechanisms of manual therapy treatments. (10) Even the most sophisticated research into the effects of exposure of musculoskeletal tissue to extracorporeal shock waves cannot substitute clinical research in order to determine the optimum intensity, treatment frequency and localization of extracorporeal shock wave therapy. 

Conclusions

Our result suggests that mainly the cumulative effect of multiple effects explain the ESWT clinical success. The various effects on the musculature show that it is not only the treatment of the structu­ral damage of the underlying musculoskeletal pathology that is successful. The therapeutic outcome can be presumably achieved by treating the muscular imbalances underlying the disorder and the pain aggravating myofascial trigger points. In order to establish the ideal treatment intensity, frequency and localization for the respective indication, further clinical studies will be necessary in the future. 

References

Wuerfel T, Schmitz C, Jokinen LLJ. The Effects of the Exposure of Musculoskeletal Tissue to Extracor­­-
po­real Shock Waves. Biomedicines. 2022; 10(5):1084. 

Tobias Wuerfel will give a lecture on this at the Isokinetic Conference 2023 in London.

Untreated lesions cause higher mechani­cal loading of the surrounding intact cartilage [9, 16, 18] and have an effect on the subchondral bone [27] and on the intra-artikular mlieu, with an increase of cytokine concentration [14] and thus a premature onset of osteo­arthritis. This not only limits the patients’ function, but also causes consi­derable costs to the public health system. Thus, suitable cartilage reconstruction techniques with the specific regeneration of hyaline- or hyaline-like cartilage are required. A number of different surgi­cal procedures are already available for the treatment of focal chondral lesions, including techniques like bone marrow stimulation (microfracture (MFx), auto­logous matrix-induced chondrogenesis (AMIC)), osteochondral auto- or allograft transplantation surgery (OATS), and autologous chondrocyte implan­tation (ACI) [5, 11 – 13, 33]. Since each of these techniques has pros and cons, the treatment of chondral lesions has not been standardised and remains a challenge. 

ACI is currently seen as the treatment of choice for moderate to large chondral defects, since this procedure leads to hyaline- or hyaline-like cartilage substance with good long-term clinical outcomes [6, 7, 15, 17, 28]. The disadvantages of ACI are the high labo­ratory costs for cell expansion, limited availability in some cases, and the need for two-step surgical procedures [5, 12, 32]. In order to overcome these disadvantages, one-step procedures such as the implantation of fragmented auto­logous or allogenic cartilage have been deve­loped (Minced Cartilage Implantation (MCI)). The underlying principle was already described in the early 1980s by Albrecht et al. [1, 2] and picked up again by Lu et al. in 2006 [22]. Over the past few years interest in MCI has grown considerably especially due to several advantages, such as being a single stage procedure that can be performed in an arthroscopic or mini-arthrotomy surgical approach and may offer strong biologic potential [5, 32].

Biology

In their in vivo milieu chondrocytes have the potential to proliferate phy­siologically [3, 32]. Furthermore, mechanical stimuli play an important role in chondrocyte proliferation and chondrogenic differentiation [36, 37]. This complex biochemical and biomechanical intra-articular milieu, that can barely be reproduced in vitro, could be a major advantage regarding the biological potential of the MCI procedure. It has been shown that mincing healthy cartilage “activates” the chondrocytes and leads to a physiological reaction with chondrogenic proliferation and the production of extracellular matrix (ECM) [22 – 24, 32]. Mincing can be achieved with a scalpel, specially developed min­cing devices, or arthroscopic shavers [19, 20, 32]. The cartilage is harvested from the margins of the chondral defect or from zones of the joint that are subjected to less loading. The outgrowth of activated chondrycytes is promoted by this enlargement of the tissue surface [4, 5, 20, 22, 32]. Ultimately this leads to the regeneration of hyaline and/or hyaline-like cartilage [22, 32, 35].

Surgical technique

The preoperative planning of a chondro­plasty procedure includes a mandatory MRI and conventional radiographs (whole-leg) [31] to detect and treat any comorbidities such as ligamentous instability, meniscus defects or mecha­nical axial malalignment. The final planning of the chondroplasty is only completed following detailed arthroscopic diagnostic investigation of the defect. The cartilage can then be harvested with osteochondral cylinders from zones that are barely load-bearing (e.g. the intercondylar notch), or using ring curettes and shavers [31, 33]. When using osteochondral cylinders the cartilage must be separated from the bone and then minced with a scalpel or shaver until it has reached a paste-like consis­tency. During arthroscopic cartilage harvesting this is done exclusively with a shaver [33]. After preparing the defect and creating stable cartilage margins the joint is aspirated, the defect zone is dried, and the minced cartilage is introduced into the defect. Depending on the technique being used, autologous thrombin and PRP, fibrin glue and/or a membrane are used for stable fixation of the fragments [25, 26, 31 – 33].  

Clinical data

Clinical evidence on autologous MCI is still limited [8, 10, 25]. In 2015, Christensen et al. [8] treated eight patients with osteochondrosis dissecans of the knee joint with a combination of auto­logous bone graft and autologous cartilage fragments embedded in fibrin glue (autologous dual-tissue transplantation (ADTT)). One year later there was a marked improvement in the MOCART score (Magnetic Resonance Observation of Cartilage Repair Tissue) from 22 to 52 points. In 2019, Massen et al. [25] conducted a consecutive two-year study of patients with (osteo-)chondral lesions who had been treated with autologous MCI. At the final follow-­up examination a significant reduction in pain was observed. Moreover, a significant radiological improvement in the MOCART score was seen. In 2020, Cugat et al. [10] treated 15 patients with full-surface (osteo-)chondral lesions using autologous MCI embedded in platelet-poor plasma (PPP) and PRP. After 15 months they also observed statistically significantly better scores on the visual analogue scale (VAS) for pain, the Lysholm score, the subjective International Knee Documentation Committee (IKDC) score, the Western Ontario and the McMaster Universities Osteoarthritis Index (WOMAC) for pain and function, the Lequesne-Index and the Short Form 12 (SF-12). While the above-named clinical studies were conducted on the knee joint, autologous MCI is also used in other joints (hip, shoulder, ankle) [21, 29, 30, 34]. In summary it may be said that the clinical data to date show good results with low complication and revision rates which are comparable to other cartilage repair techniques (ACI). 

Case study

A 37-year-old patient, an active sportsman, consulted us after multiple left knee sprains; first sprain in 2005. Since then intermittent symptoms in the left knee joint, prone to swell. The clinical examination showed articular effusion with pain on pressure over the medial joint space and mild crepitation in the medial compartment when testing movement, ROM extension/flexion 3-0-145° pain-free. Joint with stable ligaments. The Knee Injury and Osteoarthritis Outcome Score (KOOS) for pain was 50 before surgery, the quality of life score for the knee was 25 points, and 44 for activities of daily living (0 = extreme knee problems, 100 = no knee-related impairment). The Marx activity rating scale (MARS) was initially 0 points (0 = lowest physical and sporting acti­vity, 16 = highest physical and sporting activity). The MRI showed grade 4 cartilage damage over the medial femoral condyle (Fig. 1). The preoperative AMADEUS score for the medial cartilage lesion was 60 points. Minced cartilage implantation was indicated. 

The arthroscopic operation with the implantation of minced cartilage in the medial femoral condyle using the pro­duct Autocart (Arthrex) was performed. During the operation we diagnosed a 3 cm² ICRS grade 3B chondral lesion over the medial femoral condyle (Fig. 2). The postoperative course was complication-free. Follow-up treatment consisted of six weeks’ partial 15 kg weight-­bearing on the left. The range of motion was limited to 60° for weeks one, two and three, and to 90° for weeks four, five and six. The patient was initially splinted with a Mecron brace, which was replaced with a rigid frame brace in the later course. He had physiotherapy for three months after surgery. At the check-up two months after surgery he still had some residual symptoms with a ROM in extension/flexion of 0-0-90° and his quadriceps muscles were still weakened.

Fig. 2 Intra-operative arthroscopic images showing the untreated cartilage damage (a)
and the lesion after preparation of stable cartilage margins (b) and implantation of the minced cartilage (c).

After eight months the patient then reported a satisfactory surgical outcome with improved movement and a clinically irritation-free knee joint. One year after surgery the patient was still satisfied and was able to re-initiate low-impact sporting activities (cycling). After two years the patient had reached his regular everyday level, and inten­si­fi­cation of sporting activities in the low-­impact range was possible. The clinical outcome parameters showed an improvement in the KOOS score for pain (from 50 to 53 points), knee-related quality of life (from 25 to 38 points) and activities of daily living (from 44 to 71 points). The MARS had also increased from 0 points before the operation to 6 points afterwards. The MRI two years after surgery showed a corresponding satisfactory outcome with a MOCART score of 95 points (Fig. 3).

Summary and outlook

On the basis of the available in vitro and in vivo data, autologous MCI is a pro­mising one-step chondral repair pro­cedure with great biological and clinical potential. Further medium- to long-term comparative studies on large patient cohorts with clinical, functional and radiological data are required to determine the optimal defect size for MCI and the durability of the repair cartilage, and to enable comparison with other, established chondral repair procedures.

Literature

1. Albrecht F, Roessner A, Zimmermann E (1983) Closure of osteochondral lesions using chondral fragments and fibrin adhesive. Arch Orthop Trauma Surg (1978) 101:213-217
2. Albrecht FH (1983) [Closure of joint cartilage defects using cartilage fragments and fibrin glue]. Fortschr Med 101:1650-1652
3. Barry F, Murphy M (2013) Mesenchymal stem cells in joint disease and repair. Nat Rev Rheumatol 9:584-594
4. Bonasia DE, Marmotti A, Mattia S, Cosentino A, Spolaore S, Governale G, et al. (2015) The Degree of Chondral Fragmentation Affects Extracellular Matrix Production in Cartilage Autograft Implantation: An In Vitro Study. Arthroscopy 31:2335-2341
5. Bonasia DE, Marmotti A, Rosso F, Collo G, Rossi R (2015) Use of chondral fragments for one stage cartilage repair: A systematic review. World J Orthop 6:1006-1011
6. Brittberg M, Lindahl A, Nilsson A, Ohlsson C, Isaksson O, Peterson L (1994) Treatment of deep cartilage defects in the knee with autologous chondrocyte transplantation. N Engl J Med 331:889-895
7. Chimutengwende-Gordon M, Donaldson J, Bentley G (2020) Current solutions for the treatment of chronic articular cartilage defects in the knee. EFORT Open Rev 5:156-163
8. Christensen BB, Foldager CB, Jensen J, Lind M (2015) Autologous Dual-Tissue Transplantation for Osteochondral Repair: Early Clinical and Radiological Results. Cartilage 6:166-173
9. Coetzee JC, Giza E, Schon LC, Berlet GC, Neufeld S, Stone RM, et al. (2013) Treatment of osteochondral lesions of the talus with particulated juvenile cartilage. Foot Ankle Int 34:1205-1211
10. Cugat R, Alentorn-Geli E, Navarro J, Cusco X, Steinbacher G, Seijas R, et al. (2020) A novel autologous-made matrix using hyaline cartilage chips and platelet-rich growth factors for the treatment of full-thickness cartilage or osteochondral defects: Preliminary results. J Orthop Surg (Hong Kong) 28:2309499019887547
11. Dekker TJ, Aman ZS, DePhillipo NN, Dickens JF, Anz AW, LaPrade RF (2021) Chondral Lesions of the Knee: An Evidence-Based Approach. J Bone Joint Surg Am 103:629-645
12. Evenbratt H, Andreasson L, Bicknell V, Brittberg M, Mobini R, Simonsson S (2022) Insights into the present and future of cartilage regeneration and joint repair. Cell Regen 11:3
13. Flanigan DC, Harris JD, Trinh TQ, Siston RA, Brophy RH (2010) Prevalence of chondral defects in athletes‘ knees: a systematic review. Med Sci Sports Exerc 42:1795-1801
14. Fraser A, Fearon U, Billinghurst RC, Ionescu M, Reece R, Barwick T, et al. (2003) Turnover of type II collagen and aggrecan in cartilage matrix at the onset of inflammatory arthritis in humans: relationship to mediators of systemic and local inflammation. Arthritis Rheum 48:3085-3095
15. Gikas PD, Bayliss L, Bentley G, Briggs TW (2009) An overview of autologous chondrocyte implantation. J Bone Joint Surg Br 91:997-1006
16. Gratz KR, Wong BL, Bae WC, Sah RL (2009) The effects of focal articular defects on cartilage contact mechanics. J Orthop Res 27:584-592
17. Grevenstein D, Mamilos A, Schmitt VH, Niedermair T, Wagner W, Kirkpatrick CJ, et al. (2021) Excellent histological results in terms of articular cartilage regeneration after spheroid-based autologous chondrocyte implantation (ACI). Knee Surg Sports Traumatol Arthrosc 29:417-421
18. Guettler JH, Demetropoulos CK, Yang KH, Jurist KA (2004) Osteochondral defects in the human knee: influence of defect size on cartilage rim stress and load redistribution to surrounding cartilage. Am J Sports Med 32:1451-1458
19. Hunziker EB, Quinn TM, Hauselmann HJ (2002) Quantitative structural organization of normal adult human articular cartilage. Osteoarthritis Cartilage 10:564-572
20. Levinson C, Cavalli E, Sindi DM, Kessel B, Zenobi-Wong M, Preiss S, et al. (2019) Chondrocytes From Device-Minced Articular Cartilage Show Potent Outgrowth Into Fibrin and Collagen Hydrogels. Orthop J Sports Med 7:2325967119867618
21. Lorenz CJ, Freislederer F, Salzmann GM, Scheibel M (2021) Minced Cartilage Procedure for One-Stage Arthroscopic Repair of Chondral Defects at the Glenohumeral Joint. Arthrosc Tech 10:e1677-e1684
22. Lu Y, Dhanaraj S, Wang Z, Bradley DM, Bowman SM, Cole BJ, et al. (2006) Minced cartilage without cell culture serves as an effective intraoperative cell source for cartilage repair. J Orthop Res 24:1261-1270
23. Marmotti A, Bruzzone M, Bonasia DE, Castoldi F, Rossi R, Piras L, et al. (2012) One-step osteochondral repair with cartilage fragments in a composite scaffold. Knee Surg Sports Traumatol Arthrosc 20:2590-2601
24. Marmotti A, Bruzzone M, Bonasia DE, Castoldi F, Von Degerfeld MM, Bignardi C, et al. (2013) Autologous cartilage fragments in a composite scaffold for one stage osteochondral repair in a goat model. Eur Cell Mater 26:15-31; discussion 31-12
25. Massen FK, Inauen CR, Harder LP, Runer A, Preiss S, Salzmann GM (2019) One-Step Autologous Minced Cartilage Procedure for the Treatment of Knee Joint Chondral and Osteochondral Lesions: A Series of 27 Patients With 2-Year Follow-up. Orthop J Sports Med 7:2325967119853773
26. Matsushita R, Nakasa T, Ishikawa M, Tsuyuguchi Y, Matsubara N, Miyaki S, et al. (2019) Repair of an Osteochondral Defect With Minced Cartilage Embedded in Atelocollagen Gel: A Rabbit Model. Am J Sports Med 47:2216-2224
27. Minas T, Nehrer S (1997) Current concepts in the treatment of articular cartilage defects. Orthopedics 20:525-538
28. Riboh JC, Cvetanovich GL, Cole BJ, Yanke AB (2017) Comparative efficacy of cartilage repair procedures in the knee: a network meta-analysis. Knee Surg Sports Traumatol Arthrosc 25:3786-3799
29. Roth KE, Klos K, Simons P, Ossendorff R, Drees P, Maier GS, et al. (2021) [Cartilage chip transplantation for cartilage defects of the first metatarsophalangeal joint]. Oper Orthop Traumatol 33:480-486
30. Roth KE, Ossendorff R, Klos K, Simons P, Drees P, Salzmann GM (2021) Arthroscopic Minced Cartilage Implantation for Chondral Lesions at the Talus: A Technical Note. Arthrosc Tech 10:e1149-e1154
31. Salzmann GM, Calek AK, Preiss S (2017) Second-Generation Autologous Minced Cartilage Repair Technique. Arthrosc Tech 6:e127-e131
32. Salzmann GM, Ossendorff R, Gilat R, Cole BJ (2021) Autologous Minced Cartilage Implantation for Treatment of Chondral and Osteochondral Lesions in the Knee Joint: An Overview. Cartilage 13:1124S-1136S
33. Schneider S, Ossendorff R, Holz J, Salzmann GM (2021) Arthroscopic Minced Cartilage Implantation (MCI): A Technical Note. Arthrosc Tech 10:e97-e101
34. Schumann J, Salzmann G, Leunig M, Rudiger H (2021) Minced Cartilage Implantation for a Cystic Defect on the Femoral Head-Technical Note. Arthrosc Tech 10:e2331-e2336
35. Tseng TH, Jiang CC, Lan HH, Chen CN, Chiang H (2020) The five year outcome of a clinical feasibility study using a biphasic construct with minced autologous cartilage to repair osteochondral defects in the knee. Int Orthop 44:1745-1754
36. Tsuyuguchi Y, Nakasa T, Ishikawa M, Miyaki S, Matsushita R, Kanemitsu M, et al. (2021) The Benefit of Minced Cartilage Over Isolated Chondrocytes in Atelocollagen Gel on Chondrocyte Proliferation and Migration. Cartilage 12:93-101
37. Wang N, Grad S, Stoddart MJ, Niemeyer P, Reising K, Schmal H, et al. (2014) Particulate cartilage under bioreactor-induced compression and shear. Int Orthop 38:1105-1111

In modern society, physical and mental regeneration plays an increasingly important role in restoring overall performance. Relaxation, serenity, well-being and contentment are closely linked to work-life balance and mindfulness. ­Regeneration is thus an important tool for improving self-regulation, whether to relieve acute/chronic states of ten­-sion or to manage stress with ritualised settings. By definition, regeneration (from Latin: re – back, generare – to produce, generate) means renewed revival and revitalisation of the organism. It is therefore of great importance in medicine, sport and society in terms of the functional and morphological restoration of physical resources.

“Trinity of health” and further measures

In addition to the “trinity of health” (E. Rambourg), consisting of sleep, nutrition and exercise, other regeneration measures available include autogenic training, yoga, medi­tative practices, physical & manual treatments as well as functional relaxation (such as fascia or biofeedback trai­ning). Balanced sleep has now become an elusive luxury. In times of social media and the so-called meritocracy, “career” people boast about how little sleep they need because they lead supposedly exciting, successful and demanding lives and perform multiple tasks at the same time. Sleeping is said to be a waste of time and a waste of life because an 8-hour night’s rest would mean missing 1/3 of your life. Or have you ever heard someone bragging about how well they sleep and how it makes them feel energetic and full of energy? Yet, according to studies, many people suffer from sleep disorders and the associated side effects. The book “Why we sleep” by the US neuroscientist and sleep researcher Matthew Walker impressively shows, among other things, the importance of sleep in preventing Alzheimer’s, cancer and heart attacks. Sleep may not yet be sexy enough, but this seems to be changing. Customers are willing to pay to recharge their batteries on stressful work days. Whether at Dreamery by Casper, a New York Nap Bar, where a 45-minute nap costs $25, or in France at the so-called ZZZen Trucks, where mobile opportunities for relaxation are offered. 

Sleep disorders and the importance of melatonin

When dealing with the topic of sleep disorders, stress, physical or mental illnesses, medication, alcohol and caffeine consumption, hormonal metabolic changes, shift work, but also, especially in sports, travel and late kick-off times play a decisive role. When it comes to nutrition to improve sleep, the media regularly mention valerian, vitamins B1 and B6 and, most recently, melatonin, the natural sleep hormone. Melatonin controls the day-night rhythm and is synthesised from serotonin, which is obtained from the essential amino acid tryptophan. In addition to promoting sleepiness and facilitating falling asleep, melatonin acts as a radical scavenger in mitochondria (“powerhouse of the cell”) and promotes the expression of anti­oxidant enzymes. The queen among foods is the Montmorency tart cherry from Michigan/USA. With its high ­nutrient (secon­dary plant substances) and melatonin content, it is an antioxi­dant, promotes sleep and also has anti-­inflammatory and uric acid-lowering effects.

Elevated uric acid levels play an essential role in sports medi­cine regarding acute and chronic diseases and injuries. Elevated plasma and tissue levels of uric acid are found in about 30 % of men and 3 % of women [1]. In men, this is indepen­dent of age. Women initially benefit from the uricosuric effect of oestrogens, which leads to lower uric acid levels. After the menopause, however, the levels rise due to changes in the hormone ba­lance. If the uric acid in the blood rises above 7 mg/dL, e.g. through physical work or sport, it can precipitate in crystalline form and be deposited in the efferent urinary tract, in the bloodstream and in bradytrophic tissues such as tendons and cartilage [2, 3]. For example, the connection between tendinopathies and hyperuricemia has been documented several times in the literature, and is basically old hat [4]. Dodds et al. from New Zealand compared the serum uric acid levels of 30 patients with Achilles tendon rupture with those of 30 healthy controls matched for age and sex. Serum uric acid levels were significantly higher in patients with a ruptured Achilles tendon than in controls. This finding was not dependent on gender or ethnicity [5]. Uric acid deposits between the tendon cells decrease stiffness and reduce the elasticity of the tendon tissue. It is therefore assumed that this finding may be related to an adverse effect on tendon nutrition.

Chronic inflammations

Uric acid deposits in the body can be impressively displayed and detected by special CT examinations (dual-energy CT). And these chronic inflammations, some of which are very stubborn, pre­sent us with major challenges in our daily practice, especially when conventional therapies do not show sufficient effect. From a preventive and therapeutic point of view, the Montmorency tart cherry provides us with a natural and potent tool for dietary management to lower uric acid and thus have an anti-­inflammatory effect. The tart cherry juice inhibits the enzyme xanthine oxi­dase, which is necessary for the formation of uric acid [6]. Another study showed that drinking 30 – 60 mL Montmorency tart cherry juice concentrate increased uric acid excretion in volunteers by 250 %, resulting in a 36 % decrease in blood uric acid concentration [7]. Eating cherries can reduce the risk of a gout attack by  35 %, as a cherry juice concentrate by 45 %, and in combination with allopurinol even by up to 75 % in a total of 600 subjects [8]. 

Xanthine oxidase inhibitors are usually administered to prevent the “salting out” (crystallisation) of uric acid (urate). Active substances on the market are allopurinol and febuxostat. They have a uricostatic effect, i.e. they inhibit the synthesis of uric acid. However, uric acid crystals that have already been deposited cannot be removed from the tissues with these active substances. This can be achieved, for example, by eating grapes or so-called uricosurics, which can help dissolve urate crystals and make them easier to excrete. 

Practical example

The following practical example shows how significant strategic use can be for the short-term treatment of uric acid:

The MRI image on the left shows a recalcitrant tendinosis with partial rupture of the proximal patellar tendon in a 19-year-old professional football player, which could not be alleviated by phy­siotherapy, shockwave or injection treatments. Surgery was now recommended and he presented at our practice for further assessment. After the use of 100 mg benzbromarone (uricosuric), the symptoms and inflammation were reduced in the MRI after only 14 days (Fig. 1 right MRI follow-up after two weeks). 

Conclusion

Montmorency tart cherry lowers uric acid levels naturally, effectively and without any known side effects (primary prevention). The Montmorency tart cherry concentrate can be easily integrated into a performance-oriented diet and is perfect as post-workout nutrition (shakes / capsules). It has the extraordinary potential to support regeneration after sports. It has an antioxidant effect, inhibits stress-induced inflammation, and improves sleep quality with its high melatonin content. “Mens sana in corpore sano”, a Latin phrase from the ­Roman poet Juvenal, means “a healthy mind in a healthy body”. The triad of sleep, nutrition and exercise provides us with the natural foundations for this. 

Literature

[1] Gresser U, Gathof BS, Zöllner N: Uric acid levels in Southern Germany, 1989

[2] Rakestraw N: Chemical factors in fatigue: The effects of muscular exercise upon certain common blood constituents J Biol Chem, 1921

[3] Levine, S. A., Gordon, B., & Derick, C. L.: Some changes in the chemical constituents of the blood following a marathon race. Journal of the American Medical Association, 1924

[4] Clement, D. B., Taunton, J. E. and Taunton, C. A.: The relationship between uric acid and tendonitis in the endurance athlete. 6th Annual Meeting, Canadian Association of Sports Sciences, 1972

[5] Dodds WN, et al., the relationship between Achilles tendon rupture and serum uric acid level, 1984

[6] Haidari, F et al. Inhibitory Effects of Tart Cherry (Prunus cerasus) Juice on Xanthine Oxidoreductase Activity and its Hypouricemic and Antioxidant Effects on Rats, 2009

[7] Bell, P. G. et al. Montmorency tart cherry (Prunus cerasus L.) concentrate lowers uric acid, independent of plasma cyanidin-3-O-glucosiderutinoside, 2014

[8] Zhang, Y., Neogi, T., Chen, C., Chaisson, C., Hunter, D. J., & Choi, H. K., Cherry consumption and decreased risk of recurrent gout attacks, 2012

Initially there were few recommendations for returning to play after infections of the upper airways [2]. As the focus narrowed on the COVID-19 pandemic, recommendations on returning to sporting activities were published that were in line with the changes in the virus variants themselves [3 – 5]. Besides the individual course of viral infections, individual assessment is equally important, especially for elite athletes due to the usually more rapid resumption of training or even competitive sports. Medical evaluation in such cases poses a priority conflict between the athlete’s primary welfare and the aim of enabling the athlete to resume sports as quickly as possible.

Monitoring HRV & Orthostatic Testing

Monitoring heart rate variability (HRV) and performing an orthostatic test can serve as additional parameters for this. Since these measurements are often routinely carried out in top athletes anyway when deciding on the intensity of trai­ning, individual reference parameters for each athlete are available for comparison. The normal course of heart rate after orthostasis is as follows: the resting rate is followed by an initial rapid compensatory increase in heart rate followed by counter-regulation and a subsequent plateau compared with the supine resting heart rate, and a slightly higher heart rate when standing. The changes in heart rate and the HRV reflect changes in the autonomic nervous system. Infections are usually associated with increased heart rate at rest, with limited HRV and particularly with a higher peak of the maxi­mum heart rate. Furthermore, there is only little counter-­regulation of the heart rate, if any, when standing. Experience with SARS-CoV-2 infections showed deviations from this, often with an unchanged or even lower resting heart rate and considerably limited HRV. Nevertheless, the peak is higher after standing up, the higher heart rate persists, and there is a sharp drop in HRV [6].

Case study professional football player

In addition to clinical evaluation we use the orthostatic test intensively in competitive sports to guide individual intensification of training during infections. We present the case of a professional football player with a SARS-CoV-2 ­infection as an example of this. The refe­rence was a routine orthostatic test (Vantage V2 Sports Watch, Polar Electro) with the athlete’s normal supine HRV and good counter-regulation after standing up (Fig. 1). During the early phase of the infection this showed a higher heart rate at rest with limited HRV and the absence of any counter-­regulation after standing up (Fig. 2). During this phase no sporting exertion can be recommended as this may prolong the infection with potential long-term complications. During the further course of the infection when heart rate is lower and supine HRV is better there is minor counter-regulation after standing up although heart rate is higher and increases further over time, and HRV is lower (Fig. 3). At this point in time gentle aerobic training can be started. Daily monitoring and clinical parameters decide on further intensification of training. After recovery from the infection the plot is seen to be similar to the baseline condition again (Fig. 4) with good autonomic counter-regulation. Anaerobic training is possible again. Depending on the severity of the infection, regardless of the pathogen, we recommend sports cardiology diagnostic investigations with a clinical exami­nation, laboratory tests and echocardio­graphy before approving competitive sports.

Summary

Measuring HRV and performing an orthostatic test are simple additional methods for evaluating the resumption of sporting activities after infections. During viral infections these show an increased heart rate at rest and, parti­cularly, a marked increase in heart rate after standing up. HRV decreases markedly in both cases. Besides established clinical parameters, evaluation of heart rate in the orthostatic test together with HRV can be an additional tool for evalu­ating return to play.

Literature

[1] Svendsen IS et al. Training-related and competition-related risk factors for respiratory tract and gastrointestinal infections in elite cross-country skiers. Br J Sports Med 50 (13), 2016: 809-815.

[2] Scharhag J, Meyer T. Return to play after acute infectious disease in football players. J Sports Sci. 2014; 32: 1237-1242.

[3] Elliott N et al. Infographic. Graduated return to play guidance following COVID-19 infection. Br J Sports Med 2020;54:1174-5.

[4] David Salman et al. Returning to physical activity after covid-19 BMJ 2021;372:m4721

[5] Steinacker JM et al. Recommendations for return-to-sport after COVID-19: Expert consensus. Dtsch Z Sportmed. 2022; 73: 127-136. ,

[6] Hottenrott L et al. (2021) Utilizing Heart Rate Variability for Coaching Athletes During and After Viral Infection: A Case Report in an Elite Endurance Athlete. Front. Sports Act. Living 3:612782.

One patient group consists of young football players. The onset of inflam­mation in the pubic rami is very often caused by muscular imbalance that develops due to one-sided training and asymmetrical loading patterns. This is compounded by hard running surfaces e.g. artificial turf pitches, and a lack of mobility and length of the muscles close to the pelvis. In a large number of treated cases, premature and excessively intensive increases in exercise lead to recurrence and protracted downtimes. Another patient group consists of postpartum women. During the pregnancy hormones cause loosening of the pelvic ligamentous structures. This laxity in the last trimester of the pregnancy provides for widening of the birth canal, thus easing the delivery process. In a physiological situation these ligamentous structures tighten again postpartum. Any disorder of tightening of the ligamentous apparatus can lead to severe protracted pain and massive restrictions in everyday living for the women affec­ted. A history of recalcitrant and protracted pain is commonly typical in both patient groups.

Diagnostic imaging by MRI or ultrasound examination, if necessary, can confirm the diagnosis and distinguish between a number of differential diagnoses (e.g. torn adductor(s), rectus abdominis injury, inguinal hernia). A prominent feature in an MRI scan is bone marrow oedema, usually encountered bilaterally, in the pubic regions close to the symphysis. Oedematous spread is usually asymmetrical and mostly correlates with the side with more conspicuous symptoms. The so-called secondary cleft sign, the formation of an asymmetrical fissure, can often be seen within the symphysis. In many cases, poor muscular control of the local stabilisers of the lumbar spine and the hip joint as well as hypertonia, e.g. of the iliopsoas muscle, can be observed. The effects of using extracorpo­real shockwave therapy to treat musculoskeletal tissue have been compiled comprehensively in a recent systematic review [1]. When treating bone, extracorporeal shockwave treatment causes activation of the stem cells, the osteoblasts. Hence radial extracorporeal shockwave therapy should be included in the holistic treatment regimen for this indication.

Showing the muscle activity with the help of electromyography (EMG) is very helpful for recognising neuromuscular activity patterns which are then applied specifically in biofeedback training. This enables the therapist and patient to objectify and feel how the specific target musculature is optimally trained and activated. Since its start a few years ago, patients can access training plans based on an app to accompany the the­rapy process and promote the patient’s autonomous training. This way the phy­siotherapist/trainer can draw up the individual exercise programme and forward it with an app to the patient who, in turn, documents his/her trai­ning including the course of the pain.

Case Report

The [female] patient, 32, athletic with persisting and chronic progressive pain in the region of the symphysis with increased radiation into the left groin presented at the practice. The pain began in the last third of her pregnancy, but these pains have now been constant for 1.5 years and limit all activities of daily life. Over the course of time she had tried several classic physiotherapy approaches and treatment, all of which, however, resulted in brief improvement at most. As soon as she increased the intensity of her activity and training in the past the pain reoccurred very severely. For his diagnosis the attending physician had ordered another MRI examination which, compared with the previous examination, showed spread of the bone marrow oedema on both sides, and the left ramus of the pubic bone was clearly more conspicuous. During the gait analysis at the baseline examination the patient showed considerably shortened step length on the left and an increase in the stride width. During the standing examination the lordosis of the lumbar spine was seen to be very pronounced, which was associated with poor activity of the anterior musculature. Her left-sided pain could be provoked by her standing on one leg. The Thomas test was conspi­cuous on both sides. The manual the­rapy examination of the lumbar spine and the hip joint was inconspicuous and was not connected with her pain.

Treatment Protocol

DAY 1: TREATMENT 1

• Radial ESWT (Electro Medical System, Swiss Dolorclast Evoblue, Nyon – 25 Hz; 1.4 bar; 1.5 cm handpiece; 3000 impulses targeted at the region of the bone marrow oedema)
• Myofascial treatment of the iliopsoas muscle.

Fig. 1 Treatment of bone marrow oedema/pubic bone. Handpiece is held/guided by the patient’s fingers.

DAY 5: TREATMENT 2

• radial ESWT (25 Hz; 1.8 bar 4500 impulses)
• Myofascial treatment of the iliopsoas muscle.
• Training programme drawn up (App: Lanista Athlet, MP Sports Coaching & Consulting GmbH, Munich) – bridging on both sides, squats, segmental pelvic movements sitting.

DAY 9: TREATMENT 3

• Pain-free in everyday living since second treatment; step length and stride width normal
• Radial ESWT (25 Hz; 2.6 bar 5000 impulses)
• Biofeedback Training (EMG System, Menios GmbH, Ratingen) local stabilisers (multifidi, int./ext. obliques).
• Expanded training programme – activation of the local stabilisers incl. pelvic floor in diverse functional starting positions.

DAY 21: TREATMENT 4

• Radial ESWT (25 Hz; 2.7 bar 5000 impulses)
• Biofeedback training of the local stabilisers with dynamic asym­metric exercises (single-legged squats, standing balance exercise, side lunge)
• Expanded training programme – asymmetrical exercises, some dynamic
• MRI check-up before treatment 5: ”Complete regression of the bone marrow oedema in the pubic bone on both sides, no evidence of any other pathological conditions in the region examined“.

DAY 48: TREATMENT 5

• Radial ESWT (25 Hz; 2.7 bar 4500 impulses)
• Biofeedback training of local stabilisers when jumping (two-­legged, one-legged short distance)
• Exercise programme drawn up with the training objective of 30 min. pain-free jogging

Summary

With the help of radial shockwave therapy the patient was quickly relieved of her chronic progressive pain. Thus, the new radiology appointment showed complete resolution of the bone marrow oedema. The possibility of using EMG in the biofeedback training resulted in effective and targeted training. By using digital training planning the patient was able to work on her muscular deficits autonomously under ongoing checks by the physiotherapists. The patient’s motivation and compliance were positively supported by these digital checks on her training results. However, the research carried out for this article has also showed that there are as yet no gene­rally valid training protocols for this indication, and that training very often depends on the practical experience of the therapist/trainer. Further sports/phy­siotherapy studies/training protocols would be helpful for this.

Literatur

[1] Wuerfel, T.; Schmitz, C.; Jokinen, L.L.J. The Effects of the Exposure of Musculoskeletal Tissue to Extracorporeal Shock Waves. Biomedicines 2022, 10, 1084. https://doi.org/10.3390/biomedicines10051084

Creatine supplementation increases cellular energy availability and supports general health, fitness, and well-being throughout the lifespan [4 – 6]. Research over the last 30 years has shown that creatine supplementation has a number of potential health benefits and uses in clinical populations [5]. In fact, as the public has become aware of the potential health benefits of creatine, worldwide sales of products containing creatine have more than doubled [7]. The following describes the role of creatine supplementation on health as we age. For more information on each of these topics, see CreatineForHealth.com.

1. Promote Reproductive Health

Creatine plays a key role in metabolism, including in reproductive health, pregnancy and newborn health [8]. In this regard, there is evidence that creatine availability affects sperm quality, moti­lity, and viability [9]. Consequently, creatine supplementation has been suggested for men with low sperm count as well as added to medium during intrauterine insemination in order to enhance sperm motility and fertilization success [5]. Moreover, there is a greater maternal need for dietary creatine du­ring fetal development [8, 10]. Low creatine availability during pregnancy has been associated with low birth weight and pre-term birth [11, 12]. Increasing the dietary availability of crea­tine during the third trimester has been reported to reduce the risk and complications of fetal asphyxia during childbirth (i.e., lack of oxygen) and brain trauma in animals [8, 10 – 12]. Creatine has also been suggested as a means to enhance the ability of the mother to withstand and recover from contractions during natural childbirth as well as promote women’s health throughout the lifespan [10]. Although more research is needed, these findings suggest creatine plays an important role in reproductive health for both men and women.  

2. Promote Maturation in Children and Adolescents

Some children are born with creatine synthesis enzyme deficiencies and can’t synthesize enough creatine to maintain normal brain and muscle levels. This typically presents with delayed motor and cognitive maturation. Creatine supplementation in children with some forms of creatine synthesis deficiencies has been reported to have better neuro­muscular and cognitive development [13 – 15]. Additionally, low dietary intake of creatine has been correlated with a shorter stature, lower body weight, and higher percentage of body fat in children and adolescents aged 2 – 19 years [16, 17]. These findings suggest that dietary availability of creatine is important for normal growth and ma­turation. Since dietary creatine is primarily obtained from red meat, chicken, pork, and fish like salmon (e.g., 0.4 – 0.8 grams per serving), parents should ensure their children consume sufficient amounts of these foods in their diet and supplement their diet with pure crea­tine monohydrate if dietary intake is inadequate (e.g., 1 teaspoon is about
5 grams). 

3. Enhance Fitness in Active Adults

While there are a number of studies indicating that creatine supplementation (e.g., 0.3 g/kg/d for 5 – 7 days and 0.03 g/kg/d thereafter) increases strength, muscle mass, and performance in athletes engaged in strength and conditioning programs [18], it can also help indi­vi­duals starting exercise programs observe greater success, recreational athletes improve performance and training adaptations, and active individuals maintain fitness and muscle mass [5]. In fact, while creatine is often thought to be a supplement for athletes, the lar­gest consumer market for sports nutrition supplements are middle-aged adults trying to maintain strength, muscle mass, and fitness as they age. Consequently, creatine is commonly used by active adults to enhance fitness levels and performance in recreational sport activities [5, 10, 19]. 

4. Maintain Health, Fitness, and Cognitive Function as we Age

One of the greatest potential uses of creatine is as a nutritional countermea­sure to slow the negative effects of aging [19]. As we age, we typically lose strength and muscle mass while gaining body fat (i.e., adult onset of obesity). We also experience cognitive decline and me­mory loss. Dietary intake of creatine and/or the ability to digest foods containing creatine generally declines as we age leading to lower muscle and brain creatine content. Creatine supplementation in older populations has been found to increase strength and muscle mass as well as help maintain bone mass and reduce risk to falls [19, 20]. There is also evidence that creatine supplementation increases creatine content in the brain and thereby enhances cognitive function and memory in older individuals [21, 22]. Additionally, creatine supplementation while maintaining an energy-restricted diet may be an effective way to preserve muscle and help manage adult-onset obesity. Consequently, daily supplementation of pure creatine monohydrate (e.g., 3 – 5 g/d) may be more important as we age to maintain functional capacity, cognitive function, and memory.  

5. Help Manage Chronic Disease and Reduce Risk to Injury

In addition to general health benefits, there is also evidence that a lack of availability of creatine impairs cellular function and can complicate management of a number of diseases [4, 6]. For example, creatine has been reported to improve glucose homeostasis [23] and have anti-inflammatory [4 – 6, 10, 21, 24], antioxidant [5, 24, 25] and immunomodulating [26] effects. There is also evidence that creatine serves as an important energy source during ischemic conditions (e.g., ischemic heart disease, heart attack, stroke) [5, 24], brain and spinal cord injury/trauma [3, 5, 21, 27, 28], T-cell antitumor immunity [29, 30], and the pathology of some mitochondrial dysfunction conditions [6]. For this reason, creatine supplementation has been studied as an adjunctive therapeutic strategy in various clinical populations. For example, creatine supplementation has been reported to help individuals with type 2 diabetes mellitus better manage blood glucose levels when combined with resistance-trai­ning [23]. Moreover, some therapeutic benefits have been reported related to vascular disease [25], heart disease [24], and slowing the progression of some cancerous tumors [29, 30]. Feeding ­animals creatine has been reported to reduce the size and severity of heart, brain, and spinal cord damage in response to experimentally-induced ischemic conditions, traumatic brain injury, and spinal cord injury [3, 5, 6, 21, 24, 27, 28]. In fact, the International Society of Sports Nutrition recommends that individuals at risk to head and/or spinal cord injury consider ­taking creatine for neuroprotection [1]. Finally, there is evidence that creatine supplementation reduces the incidence and severity of musculoskeletal injuries in athletes engaged in intense training [1, 31, 32] and can promote recovery from musculoskeletal injury [33]. Therefore, creatine supplementation may play an adjunctive role in the management of several chronic diseases, reduce risk to injury, and/or promote recovery and rehabilitation.

6. Therapeutic Nutrient for Chronic Viral Fatigue and Long-COVID? 

People often experience chronic fatigue and lethargy after exposure to viral infections. For example, millions of people who have had COVID19 complain of symptoms of fatigue, mental or brain fog, lack of energy and endurance, and lethargy for months or more after reco­vering from COVID (i.e., long-COVID). People experiencing these symptoms often reduce physical activity which can complicate recovery, promote obesity, and increase risk and/or progression of chronic disease. Since creatine can increase brain bioenergetics and has been shown to provide some therapeutic benefit for patients with chronic fatigue-­related syndromes such as post-­viral fatigue syndrome (PFS) or myalgic ence­phalomyelitis (ME), it is possible that creatine supplementation can help people with long-COVID increase physical activity and cognitive function [6, 34]. Future research should assess this potential therapeutic role of creatine supplementation.

Summary

The benefits of creatine supplementation go well-beyond enhancing high-­intensity exercise performance and training adaptations for athletes. Research has clearly shown a number of health and/or potential therapeutic benefits as we age and in clinical populations. Although additional research is needed to further explore the health and potential therapeutic benefits of creatine supplementation, it is recommended that people consume at least 2 – 3 grams (i.e., 0.03 g/kg/d) of creatine per day from food (e.g., red meat, chi­cken, pork, salmon, tuna) and/or dietary supplementation of pure creatine monohydrate to support general health [5]. For those interested in optimizing performance, training, and recovery, we recommend loading with a pure source of creatine monohydrate for 5 – 7 days (0.3 g/kg/d) and then ingesting main­tenance doses (0.03 g/kg/d). For those interested in taking creatine to help manage chronic disease, we suggest you share some of the peer-reviewed articles and presentations available at CreatineForHealth.com with your healthcare provider and discuss whether creatine supplementation may be something to consider to help you manage your health condition.