This edition of Cochrane Corner looks at some of the work published by the Cochrane Collaboration, covering interventions for treating distal femur fractures in adults; ultrasound and shockwave therapy for acute fractures in adults; and local corticosteroid injection versus placebo for carpal tunnel syndrome

Aim. Focused high energy extracorporeal shockwave therapy (fhESWT) is used to support fracture healing in non-union cases and has been shown to have antibacterial effects. We trialed fhESWT as an adjunct to conventional treatment in a clinically relevant rabbit model of fracture related infection. Method. A complete humeral osteotomy was performed in 31 rabbits and fixed with a 7-hole-LCP. A fracture-related infection (FRI) was established with Staphylococcus aureus. After two weeks, a revision surgery was performed with debridement, irrigation and implant retention. Rabbits then received: no further treatment (controls); shockwaves (at day 2 and 6 after revision, 4'000 Impulses each time with 23kV); systemic antibiotics (rifampin and nafcillin) over one week in weight adjusted dosages; or the combination of antibiotics and shockwaves. Treatments were applied over one week. Blood cultures were taken before and after shockwave sessions. After an additional week without treatment, rabbits were euthanized, and quantitative bacteriology was performed on implants and tissues to determine infection burden. Indicator organs (brain, heart, liver, lungs, kidneys and spleen) were cultured to assess possible bacteraemia due to fhESWT. Results. All rabbits were infected at revision surgery as determined by bacteriological culture of debrided materials. fhESWT in combination with antibiotic treatment lowered the bacterial burden at euthanasia hundredfold compared to antibiotic treatment alone in all samples (p=0.38). This effect was most prevalent for the implant sample (p=0.08). No significant effect was seen for fhESWT alone compared to untreated controls. No signs of bacteraemia occurred. Conclusions. The additon of systemic antibiotics had the biggest effect on reduction of bacteria. Although further lowering the bacterial burden in our model the effect of fhESWT as an adjunct was not big enough to be statistically secured in this in vivo rabbit model. In certain difficult-to-treat infections the addition of fhESWT might be beneficial. The method appears to be safe in this model of acute FRI as no signs of bacteremia occurred despite the high energy and impulse number. Further investigations are needed to identify the correct indication

Introduction. Greater trochanteric pain syndrome (GTPS) is a common and disabling condition characterised by pain and tenderness at or around the trochanteric area. Extracorporeal shockwave therapy (ESWT) has been described as a method of treatment. The National Institute for Clinical Excellence (NICE, UK) guidance suggests a possible benefit but with limited evidence. Materials and Methods. We retrospectively identified 71 consecutive patients who underwent ESWT for refractory GTPS over a period of 16 months. The diagnosis was made clinically. ESWT was offered to patients with refractory symptoms despite conservative treatment. Telephone interviews were used to collect data including pain scores (0–10), change in symptoms, discomfort of the procedure, and complications. Results. Fifty-nine patients (83%) were followed up. The mean time to follow up was 8 months (3 to 19). The mean age was 59 (29 to 88) with 86% females. Two-thirds had improvement in their symptoms with a significant drop of 6 points in their pain score (p<0.05); however, symptoms recurred in 60% at a mean of 3.7 months. Most patients (60%) had mild or no discomfort from the treatment. Two patients (3.3%) could not tolerate the treatment. One complication was reported; an exacerbation of sciatica symptoms which settled spontaneously. Conclusion. This study shows an improvement in the symptoms of 67% of patients with refractory GTPS, for up to 15 months, but with frequent relapsed. Further research is required to confirm whether MRI may be useful in selecting patients for ESWT

Introduction. The pathophysiology of osteonecrosis of femoral head (ONFH) is uncertain for most cases with speculation of vascular impairment and changes in cell biology due to multi-factorial etiologies including corticosteroid, alcohol, smoking, trauma, radiation or caisson disease and genetic. Extracorporeal shockwave therapy (ESWT) began with an incidental observation of osteoblastic response pattern during animal studies in the mid-1980 that generated an interest in the application of ESWT to musculoskeletal disorders. The mechanism of shockwave therapy is not fully understood but several reports showed better clinical outcomes and promoted bone remodelling and regeneration effect of the femoral head after ESWT in ONFH. Therefore, we compared the clinical results of the use of extracorporeal shock wave therapy (ESWT) on the patients with ONFH in radiographic staging. Methods. We evaluated 24 patients with 32 hip joints diagnosed ONFH treated with ESWT from 1993 to 2012. Average follow-up period was 27 months, and patients were average 47.8 aged. Association Research Circulation Osseous (ARCO) staging system was used to grade radiographic stage before treatment. All the patients were divided to two groups; group 1 (ARCO stage I,II), group 2 (ARCO stage III). Comparative analysis was done between two groups with visual analogue scale (VAS) score and Harris hip score (HHS) at pre-treatment, 3, 6, 12 and 24 months after treatments. The failure was defined when radiographic stage was progressed or arthroplasty surgery was needed due to clinical exacerbation. Results. Two groups showed all clinical improvements with VAS scoring at final follow-up (group 1: mean 6.3 to 1.6, p < 0.001; group 2: mean 7.1 to 3.3, p < 0.001). With HHS, group 1 showed a significant improvement from 64.4 to 95.4 (p < 0.001), while no significance in group 2 (p = 0.280). At final-follow-up, 3 hips of group 1 and 1 hip of group 2 showed radiographic improvement, but 2 patients were performed total hip arthroplasty due to persistent pain and dysfunction. Discussion and Conclusion. ESWT could be considered as an alternative option before surgical treatment in patients not only with early stage of ONFH but also with mid stage

Background. Shockwave therapy has been shown to induce osteoneogenesis in animal models. The mechanism of action is unclear, but experimental evidence suggests micro-fracture formation and increased blood flow as the most likely explanation. Several reports from Europe have suggested good results from the treatment of delayed fracture union with shock-waves. We present the results of a randomised double-blind placebo-controlled pilot study. Method. Fourteen patients with clinically and radiologically confirmed delayed union of long-bones consented to enter the trial. The treatment group had a single application of 3000 high-energy shockwaves using the Stortz SLK unit with image intensifier control. The control group had the exactly the same treatment but with an ‘air-gap’ interposition to create a placebo-shockwave. Each patient was followed-up with serial radiographs as well as visual analogue pain scores and EuroQol assessments. All of the patients were reviewed for a minimum of three years post treatment. Results. There was no difference between the groups in terms of time to fracture union (p=0.781 log-rank test). Nor was there any indication of a treatment effect on any of the secondary outcome measures. Conclusion. We have been unable to recreate the previously reported favourable results of shockwave therapy in the treatment of delayed fracture union. On the basis of this study we have withdrawn a proposal for a multi-centre RCT

Tendinopathy is a debilitating musculoskeletal condition which can cause significant pain and lead to complete rupture of the tendon, which often requires surgical repair. Due in part to the large spectrum of tendon pathologies, these disorders continue to be a clinical challenge. Animal models are often used in this field of research as they offer an attractive framework to examine the cascade of processes that occur throughout both tendon pathology and repair. This review discusses the structural, mechanical, and biological changes that occur throughout tendon pathology in animal models, as well as strategies for the improvement of tendon healing.

Cite this article: Bone Joint Res 2014;3:193–202.