Maarten H. Moen

Autologous growth factor injections in chronic tendinopathy: a systematic review

Chronic degenerative tendinopathies are frequent and difficult to treat. Tendon healing and regeneration may be improved by injecting autologous growth factors obtained from the patients blood. Autologous growth factors can be injected with autologous whole blood or platelet-rich plasma (PRP). Electronic databases were searched for prospective clinical trials on treatment with autologous growth factors of patients with chronic tendinopathy. Chronic tendinopathy in this study included wrist extensors, flexors, plantar fasciopathy and patellar tendinopathy. Studies examining the treatment of other tendinopathies were not identified. The Physiotherapy Evidence Database score was used to examine the methodological quality of the assessment, and a qualitative analysis was performed with the levels of evidence. There are many proposed treatment options for chronic tendinopathy. Treatments in the form of injections with autologous whole blood or PRP are increasingly used in clinical practice. There are high expectations of these regenerative injections, and there is a clear need for effective conservative therapies. All studies showed that injections of autologous growth factors (whole blood and PRP) in patients with chronic tendinopathy had a significant impact on improving pain and/or function over time. However, only three studies using autologous whole blood had a high methodological quality assessment, and none of them showed any benefit of an autologous growth factor injection when compared with a control group. At present, there is strong evidence that the use of injections with autologous whole blood should not be recommended. There were no high-quality studies found on PRP treatment. There is limited evidence to support the use of injections with PRP in the management of chronic tendinopathy. There is growing interest in the working mechanisms of autologous growth factors. The amount and mixture of growth factors produced using different cell separating systems are largely unknown and it is also uncertain whether platelet activation prior to injection is necessary. These variables should be taken into account when starting clinical studies. A good experimental model for studying tendinopathy would be helpful for basic research. Future clinical studies using a proper control group, randomization, blinding and validated disease-specific outcome measures for pain and function are needed.

Medial Tibial Stress Syndrome A Critical Review

Medial tibial stress syndrome (MTSS) is one of the most common leg injuries in athletes and soldiers. The incidence of MTSS is reported as being between 4% and 35% in military personnel and athletes. The name given to this condition refers to pain on the posteromedial tibial border during exercise, with pain on palpation of the tibia over a length of at least 5 cm. Histological studies fail to provide evidence that MTSS is caused by periostitis as a result of traction. It is caused by bony resorption that outpaces bone formation of the tibial cortex. Evidence for this overloaded adaptation of the cortex is found in several studies describing MTSS findings on bone scan, magnetic resonance imaging (MRI), high-resolution computed tomography (CT) scan and dual energy x-ray absorptiometry.The diagnosis is made based on physical examination, although only one study has been conducted on this subject. Additional imaging such as bone, CT and MRI scans has been well studied but is of limited value. The prevalence of abnormal findings in asymptomatic subjects means that results should be interpreted with caution.Excessive pronation of the foot while standing and female sex were found to be intrinsic risk factors in multiple prospective studies. Other intrinsic risk factors found in single prospective studies are higher body mass index, greater internal and external ranges of hip motion, and calf girth. Previous history of MTSS was shown to be an extrinsic risk factor.The treatment of MTSS has been examined in three randomized controlled studies. In these studies rest is equal to any intervention. The use of neoprene or semi-rigid orthotics may help prevent MTSS, as evidenced by two large prospective studies.

Efficacy of platelet-rich plasma injections in osteoarthritis of the knee: a systematic review and meta-analysis

Background The effectiveness of platelet-rich plasma (PRP) injections for osteoarthritis (OA) is still controversial. We investigated the effect of PRP injections in patients with knee OA based on decreasing pain, improving function, global assessment and changes regarding joint imaging. Methods We performed a comprehensive, systematic literature search in computerised databases (MEDLINE, EMBASE, CINAHL, CENTRAL, Web of Science and PEDro) until June 2014 for randomised or non-randomised controlled trials. These were graded for risk of bias and a level of evidence was provided. If possible, meta-analysis was performed. Results Ten trials were included. In these, intra-articular PRP injections were more effective for pain reduction (mean difference (MD) −2.45; 95% CI −2.92 to −1.98; p value <0.00001 and MD −2.07; 95% CI −2.59 to −1.55; p value <0.00001, single and double PRP injections, respectively) compared with placebo at 6 months postinjection. Intra-articular PRP injections were compared with hyaluronic acid and showed a statistically significant difference in favour of PRP on pain reduction based on the visual analogue scale and numeric rating scale (standardised mean difference −0.92; 95% CI −1.20 to −0.63; p value <0.00001) at 6 months postinjection. Almost all trials revealed a high risk of bias. Conclusions On the basis of the current evidence, PRP injections reduced pain more effectively than did placebo injections in OA of the knee (level of evidence: limited due to a high risk of bias). This significant effect on pain was also seen when PRP injections were compared with hyaluronic acid injections (level of evidence: moderate due to a generally high risk of bias). Additionally, function improved significantly more when PRP injections were compared with controls (limited to moderate evidence). More large randomised studies of good quality and low risk of bias are needed to test whether PRP injections should be a routine part of management of patients with OA of the knee.

Prevalence of radiological signs of femoroacetabular impingement in patients presenting with long-standing adductor-related groin pain

Objective A decreased range of motion (ROM) of the hip joint is known to predispose to athletic groin injury. Femoroacetabular impingement (FAI) of the hip leads to a reduced ROM. This study examined the prevalence of radiological signs of FAI in patients presenting with long-standing adductor-related groin pain (LSARGP). Design Prospective case series. Setting Outpatient Sports Medicine Department. Patients 34 athletes with LSARGP defined as pain on palpation of the proximal insertion of adductor muscle and a painful, resisted adduction test. Assessment A clinician blinded to the results of the radiological assessment performed a physical examination: iliopsoas length, hip ROM and anterior hip impingement test. Anteroposterior pelvic radiographs were examined by a second blinded clinician for the presence of: pistol grip deformity, centrum-collum-diaphyseal angle, femoral head neck ratio, coxa profunda, protrusio acetabuli, lateral centre edge angle, acetabular index and cross-over sign. Results The prevalence of radiological signs of FAI was 94% (64/68). The mean number of radiological signs in hips with LSARGP was 1.84 (range 0–4, SD 1.05) and 1.96 (range 0–5, SD 1.12) in asymptomatic groins (p=0.95). The anterior hip impingement test was positive in nine cases. There was no relationship with the number of radiological signs (p=0.95). There was no correlation between hip ROM and the number of radiological signs (p=0.37). Conclusion Radiological signs of FAI are frequently observed in patients presenting with LSARGP. Clinicians should be aware of this fact and the possible lack of correlation when assessing athletes with groin pain.

Platelet-rich plasma injections in acute muscle injury

In this randomized trial involving athletes with acute hamstring muscle injuries, injection of platelet-rich plasma did not result in shortening of the time until patients could resume their sports activity or in a reduction in reinjury rates, as compared with placebo.

Risk factors and prognostic indicators for medial tibial stress syndrome

The objective of the study was to examine the risk factors and prognostic indicators for medial tibial stress syndrome (MTSS). In total, 35 subjects were included in the study. For the risk factor analysis, the following parameters were investigated: hip internal and external ranges of motion, knee flexion and extension, dorsal and plantar ankle flexion, hallux flexion and extension, subtalar eversion and inversion, maximal calf girth, lean calf girth, standing foot angle and navicular drop test. After multivariate regression decreased hip internal range of motion, increased ankle plantar flexion and positive navicular drop were associated with MTSS. A higher body mass index was associated with a longer duration to full recovery. For other prognostic indicators, no relationship was found.

Therapeutic interventions for acute hamstring injuries: a systematic review

Background Despite the high rate of hamstring injuries, there is no consensus on their management, with a large number of different interventions being used. Recently several new injection therapies have been introduced. Objective To systematically review the literature on the effectiveness of therapeutic interventions for acute hamstring injuries. Data sources The databases of PubMed, EMBASE, Web of Science, Cochrane Library, CINAHL and SPORTDiscus were searched in May 2011. Study eligibility criteria Prospective studies comparing the effect of an intervention with another intervention or a control group without intervention in subjects with acute hamstring injuries were included. Data analysis Two authors independently screened the search results and assessed risk of bias. Quality assessment of the included studies was performed using the Physiotherapy Evidence Database score. A best evidence synthesis was used to identify the level of evidence. Main results Six studies were included in this systematic review. There is limited evidence for a positive effect of stretching, agility and trunk stability exercises, intramuscular actovegin injections or slump stretching in the management of acute hamstring injuries. Limited evidence was found that there is no effect of non-steroidal anti-inflammatory drugs or manipulation of the sacroiliac joint. Conclusions There is a lack of high quality studies on the treatment of acute hamstring injuries. Only limited evidence was found to support the use of stretching, agility and trunk stability exercises, intramuscular actovegin injections or slump stretching. Further research is needed using an appropriate control group, randomisation and blinding.

Magnetic Resonance Imaging in Acute Hamstring Injury: Can We Provide a Return to Play Prognosis?

BackgroundSports physicians are increasingly requested to perform magnetic resonance imaging (MRI) of acute hamstring muscle injuries and to provide a prognosis of the time to return to play (RTP) on the basis of their findings.ObjectivesTo systematically review the literature on the prognostic value of MRI findings for time to RTP in acute hamstring muscle injuries.Data SourcesThe databases of PubMed, EMBASE, CINAHL, Web of Science and Cochrane Library were searched in June 2013.Study Eligibility CriteriaStudies evaluating MRI as a prognostic tool for determining time to RTP in athletes with acute hamstring injuries were eligible for inclusion.Data AnalysisTwo authors independently screened the search results and assessed risk of bias using criteria for quality appraisal of prognosis studies. A best-evidence synthesis was used to identify the level of evidence.ResultsOf the 12 studies included, one had a low risk of bias and 11 a high risk of bias. There is moderate evidence that injuries without hyperintensity on fluid-sensitive sequences are associated with a shorter time to RTP and that injuries involving the proximal free tendon are associated with a longer time to RTP. Limited evidence was found for an association of central tendon disruption, injury not affecting the musculotendinous junction and a total rupture with a longer time to RTP. The other MRI findings studied showed either no association or there was conflicting evidence.ConclusionThere is currently no strong evidence for any MRI finding that gives a prognosis on the time to RTP after an acute hamstring injury, owing to considerable risks of bias in the studies on this topic.

Clinical findings just after return to play predict hamstring re-injury, but baseline MRI findings do not

Background Acute hamstring re-injuries are common and hard to predict. The aim of this study was to investigate the association between clinical and imaging findings and the occurrence of hamstring re-injuries. Methods We obtained baseline data (clinical and MRI findings) of athletes who sustained an acute hamstring injury within 5 days of initial injury. We also collected data of standardised clinical tests within 7 days after return to play (RTP). The number of re-injuries was recorded within 12 months. We analysed the association between the possible predictive variables and re-injuries with a multivariate Cox proportional-hazards regression model. Results Eighty patients were included at baseline and 64 patients could be included in the final analysis because data after RTP were not available in 16 cases. There were 17 re-injuries (27%). None of the baseline MRI findings were univariately associated with re-injury. A higher number of previous hamstring injuries (adjusted OR (AOR) 1.33; 95% CI 1.11 to 1.61), more degrees of active knee extension deficit after RTP (AOR 1.13; 95% CI 1.03 to 1.25), isometric knee flexion force deficit at 15° after RTP (AOR 1.04; 95% CI 1.01 to 1.07) and presence of localised discomfort on hamstring palpation after RTP (AOR 3.95; 95% CI 1.38 to 11.37) were significant independent predictors of re-injury. Athletes with localised discomfort on hamstring palpation just after RTP were consequently almost four times more likely to sustain a re-injury. Conclusions The number of previous hamstring injuries, active knee extension deficit, isometric knee flexion force deficit at 15° and presence of localised discomfort on palpation just after RTP are associated with a higher hamstring re-injury rate. None of the baseline MRI parameters was a predictor of hamstring re-injury. Trial registration number ClinicalTrial.gov number NCT01812564.

MRI observations at return to play of clinically recovered hamstring injuries

Background Previous studies have shown that MRI of fresh hamstring injuries have diagnostic and prognostic value. The clinical relevance of MRI at return to play (RTP) has not been clarified yet. The aim of this study is to describe MRI findings of clinically recovered hamstring injuries in amateur, elite and professional athletes that were cleared for RTP. Methods We obtained MRI of 53 consecutive athletes with hamstring injuries within 5 days of injury and within 3 days of RTP. We assessed the following parameters: injured muscle, grading of injury, presence and extent of intramuscular signal abnormality. We recorded reinjuries within 2 months of RTP. Results MRIs of the initial injury showed 27 (51%) grade 1 and 26 (49%) grade 2 injuries. Median time to RTP was 28 days (range 12–76). On MRI at RTP 47 athletes (89%) had intramuscular increased signal intensity on fluid-sensitive sequences with a mean longitudinal length of 77 mm (±53) and a median cross-sectional area of 8% (range 0–90%) of the total muscle area. In 22 athletes (42%) there was abnormal intramuscular low-signal intensity. We recorded five reinjuries. Conclusions 89% of the clinically recovered hamstring injuries showed intramuscular increased signal intensity on fluid-sensitive sequences on MRI. Normalisation of this increased signal intensity seems not required for a successful RTP. Low-signal intensity suggestive of newly developed fibrous tissues is observed in one-third of the clinically recovered hamstring injuries on MRI at RTP, but its clinical relevance and possible association with increased reinjury risk has to be determined.