Background: There is continuing controversy regarding the optimal treatment for patients with symptomatic early-stage osteonecrosis of the femoral head. We compared the results of noninvasive treatment with extracorporeal shock waves with those of core decompression and bone-grafting in similar groups of patients. Methods: Patients with stage-I, II, or III osteonecrosis were randomly assigned to be treated either with shock waves or with core decompression and nonvascularized fibular grafting. The shock-wave group consisted of twenty-three patients (twenty-nine hips), and the surgical group consisted of twenty-five patients (twenty-eight hips). The patients in the two groups had similar demographic characteristics, duration and stage of disease, and duration of follow-up. The patients in the shock-wave group received a single treatment with 6000 impulses of shock waves at 28 kV to the affected hip. The evaluation parameters included clinical assessment of pain with a visual analog pain scale, Harris hip scores, and an assessment of activities of daily living and work capacity. Radiographic assessment was performed with serial plain radiographs and magnetic resonance imaging. Results: Before treatment, the two groups had similar pain and Harris hip scores. At an average of twenty-five months after treatment, the pain and Harris hip scores in the shock-wave group were significantly improved compared with the pretreatment scores (p < 0.001). In this group, 79% of the hips were improved, 10% were unchanged, and 10% were worse. Of the hips treated with a nonvascularized fibular graft, 29% were improved, 36% were unchanged, and 36% were worse. In the shock-wave group, imaging studies showed regression of five of the thirteen lesions that had been designated as stage I or II before treatment and no regression of a stage-III lesion. Two stage-II and two stage-III lesions progressed. In the surgical group, four lesions regressed and fifteen (of the nineteen graded as stage I or II) progressed. The remaining nine lesions were unchanged. Conclusions: Extracorporeal shock-wave treatment appeared to be more effective than core decompression and nonvascularized fibular grafting in patients with early-stage osteonecrosis of the femoral head. Long-term results are needed to determine whether the effect of this novel method of treatment for osteonecrosis of the femoral head endures. Level of Evidence: Therapeutic Level I. See Instructions to Authors for a complete description of levels of evidence.

Shockwave is a rapid, short duration acoustic wave that carries energy and can propagate through tissue medium. This kind of physical force can be a mechanical stimulus that induces biological effects in living tissue. Extracorporeal shockwave therapy (ESWT) acts as a mechanical stimulus which promotes biological healing processes through a mechanotransduction. The biological effects of ESWT are reported such as tissue regeneration, wound healing, angiogenesis, bone remodeling, and anti-inflammation. Until now, however, little is known about the basic mechanism of action of this type of therapy. This article describes the molecular mechanism on the current status of ESWT with pre-clinical and clinical applications for treating disorders in bone.

Background: Chronic patellar tendinopathy is an overuse syndrome with pathologic changes similar to tendinopathies of the shoulder, elbow, and heel. Extracorporeal shockwave was shown effective in many tendinopathies. Hypothesis: Extracorporeal shockwave therapy may be more effective than conservative treatment for chronic patellar tendinopathy. Study Design: Randomized controlled clinical trial; Level of evidence, 2. Methods: This study consisted of 27 patients (30 knees) in the study group and 23 patients (24 knees) in the control group. In the study group, patients were treated with 1500 impulses of extracorporeal shockwave at 14 KV (equivalent to 0.18 mJ/mm 2 energy flux density) to the affected knee at a single session. Patients in the control group were treated with conservative treatments including nonsteroidal anti-inflammatory drugs, physiotherapy, exercise program, and the use of a knee strap. The evaluation parameters included pain score, Victorian Institute of Sports Assessment score, and ultrasonographic examination at 1, 3, 6, and 12 months and then once a year. Results: At the 2- to 3-year follow-up, the overall results for the study group were 43% excellent, 47% good, 10% fair, and none poor. For the control group, the results were none excellent, 50% good, 25% fair, and 25% poor. The mean Victorian Institute of Sports Assessment scores were 42.57 ± 10.22 and 39.25 ± 10.85, respectively, before treatment (P = .129) and 92.0 ± 10.17 and 41.04 ± 10.96, respectively, after treatment (P < .001). Satisfactory results were observed in 90% of the study group versus 50% of the control group (P < .001). Recurrence of symptoms occurred in 13% of the study group and 50% of the control group (P = .014). Ultrasonographic examination showed a significant increase in the vascularity of the patellar tendon and a trend of reduction in the patellar tendon thickness after shockwave treatment compared with conservative treatments. However, no significant difference in the appearance, arrangement, and homogeneity of tendon fibers was noted between the 2 groups. There were no systemic or local complications or device-related problems. Conclusion: Extracorporeal shockwave therapy appeared to be more effective and safer than traditional conservative treatments in the management of patients with chronic patellar tendinopathy.