Application of extracorporeal shock-waves in the treatment of pseudarthrosis of the lower extremity. Preliminary results

Callus formation and bone remodeling in a tibial nonunion after minimal invasive percutaneous screw fixation followed by extracorporeal shockwave therapy 17-months after initial trauma - A case report

INTRODUCTION

The treatment of tibial nonunion is challenging and treatment may be conservative or surgical. Conservative strategies include functional braces and weight bearing, or focused extracorporeal shockwave therapy (fESWT).

CASE DESCRIPTION

A 45-year-old male patient sustained spiral tibial shaft fractures and was treated surgically within 24 hours after the initial accident with intramedullary nails. The tibial fracture was later classified as nonunion after 11 months. Radiologic evaluation 17 months after the initial trauma demonstrated clinical nonunion, and subsequently the patient was offered a conservative approach with fESWT to facilitate an increase in callus formation. The handpiece was fitted with a stand-off II (long), penetration depth of 15 mm. Three cycles were administered in month 17, 19 and 20 after baseline. Each cycle consisted of three treatments sessions spaced with 6-8 days apart, and consisted of 3000 to 4000 impulses each given at 0.25-0.84 mJ/mm2. The number of impulses and the power at the focus point varied according to the pain response.

OUTCOMES

The patient achieved union 23 months after fracture. A clinical important improvement was observed with both Lower Extremity Functional Scale (LEFS) (18-point difference) and Patient Specific Functional Scale (PSFS) (average: 4.7 points,) The "worst pain last 24 hours" was reduced by 5 points. These values express minimal clinically important difference (MCID) values in these functional patient-reported outcome measures.

CONCLUSION

This treatment strategy may be viable in a broader setting, including private practice physiotherapy thereby treating the patient in close proximity to the patient's everyday life.

Treatment of delayed union of the forearm with extracorporeal shockwave therapy: a case report and literature review

Compared to other long bones, forearm fractures are particularly challenging due to the high rate of complications. These include malunion, delayed/nonunion, wrist and elbow movement reduction, and pain. Surgical procedure is considered the gold standard for managing delayed union and nonunion of the long bones. However, in the last decades, extracorporeal shockwave therapy (ESWT) has emerged as an effective and less invasive approach to enhance bone regeneration and fracture healing, avoiding major complications of surgical procedures. In contrast to the broad literature reporting good clinical results of ESWT in the treatment of nonunions, there is currently limited evidence regarding the clinical application of shock waves on long bone delayed fractures, particularly those of the forearm. In the present paper, we report a case of delayed bone healing of the diaphyseal region of the ulna treated with focused ESWT. The successful case experienced bone healing at the fracture site in less than 3 months after initial ESWT treatment. Acknowledging the limitation of reporting a case report, however, the remarkable clinical results and the absence of side effects contribute valuable information in support of the use of ESWT as an effective alternative to standard surgery for forearm fractures.

[Extracorporeal shockwave therapy as an alternative treatment in cases of posttraumatic delayed bone union]

BACKGROUND

Impaired posttraumatic bone healing is a relevant complication of fractures. Usually, the standard treatment is surgical revision. For about 30 years extracorporeal shockwave therapy (ESWT) has emerged as an alternative treatment option with similar consolidation rates but less complications.

OBJECTIVE

This article aims to present our data in context to the current literature MATERIAL AND METHODS: From 2007 to 2016 a total of 97 patients diagnosed with impaired posttraumatic bone healing were treated with ESWT. Clinical and demographic data of this population were retrieved and analyzed retrospectively.

RESULTS

The general consolidation rate was 60.8%. Multiple variables were analyzed. A preinterventional bone gap ≥ 5 mm, initial dislocation > ½ of the bone shaft, nicotine consumption and a long time span from fracture to ESWT (> 6 months) were found as factors which significantly impair bone healing after ESWT.

CONCLUSION

ESWT is a safe and promising alternative treatment option for delayed unions. Regarding risk factors of a poor outcome may be identified before and increase the rate of success.

Biophysical Enhancement in Fracture Healing: A Review of the Literature

Bone healing constitutes a complex process involving cellular and pathophysiological mechanisms. Despite progress in osteosynthesis techniques, fracture union continues to be challenging. In some cases, it is not ultimately achieved or is delayed relative to the expected time resulting in economic and social outcomes for the patient and the health system. In addition to surgical treatment, biophysical methods have been developed to assist in fracture healing used in combination or individually. Biophysical stimulation is a non-invasive therapy used in orthopedic practice to increase and enhance tissue's reparative and anabolic activities. This study reviewed the existing literature, including electromagnetic fields, ultrasound, laser, extracorporeal shockwave therapy, and electrical stimulation, and revealed the efficacy of biophysical stimulation for bone healing. This study aims to define if these methods are helpful, especially in cases of non-union. Biophysical stimulation requires care and precision in use to ensure the success expected of it by physicians and patients.

Extracorporeal Shockwave Therapy in the Treatment of Nonunion in Long Bones: A Systematic Review and Meta-Analysis

Background: Nonunion is one of the most challenging problems in the field of orthopedics. The aim of this study was to perform a systematic review of the literature to evaluate the effectiveness of extracorporeal shockwave therapy (ESWT) in the treatment of nonunion in long bones. Methods: We conducted a search of three databases (PubMed, Scopus, and Web of Science) and found 646 total publications, of which 23 met our inclusion criteria. Results: Out of 1200 total long bone nonunions, 876 (73%) healed after being treated with ESWT. Hypertrophic cases achieved 3-fold higher healing rates when compared to oligotrophic or atrophic cases (p = 0.003). Metatarsal bones were the most receptive to ESWT, achieving a healing rate of 90%, followed by tibiae (75.54%), femurs (66.9%) and humeri (63.9%). Short periods between injury and treatment lead to higher healing rates (p < 0.02). Conversely, 6 months of follow-up after the treatment appears to be too brief to evaluate the full healing potential of the treatment; several studies showed that healing rates continued to increase at follow-ups beyond 6 months after the last ESWT treatment (p < 0.01). Conclusions: ESWT is a promising approach for treating nonunions. At present, a wide range of treatment protocols are used, and more research is needed to determine which protocols are the most effective.

Vascularization Strategies in the Prevention of Nonunion Formation

Delayed healing and nonunion formation are major challenges in orthopedic surgery, which require the development of novel treatment strategies. Vascularization is considered one of the major prerequisites for successful bone healing, providing an adequate nutrient supply and allowing the infiltration of progenitor cells to the fracture site. Hence, during the last decade, a considerable number of studies have focused on the evaluation of vascularization strategies to prevent or to treat nonunion formation. These involve (1) biophysical applications, (2) systemic pharmacological interventions, and (3) tissue engineering, including sophisticated scaffold materials, local growth factor delivery systems, cell-based techniques, and surgical vascularization approaches. Accumulating evidence indicates that in nonunions, these strategies are indeed capable of improving the process of bone healing. The major challenge for the future will now be the translation of these strategies into clinical practice to make them accessible for the majority of patients. If this succeeds, these vascularization strategies may markedly reduce the incidence of nonunion formation. Impact statement Delayed healing and nonunion formation are a major clinical problem in orthopedic surgery. This review provides an overview of vascularization strategies for the prevention and treatment of nonunions. The successful translation of these strategies in clinical practice is of major importance to achieve adequate bone healing.

Extracorporeal Shock Wave Treatment for Delayed Union and Nonunion Fractures: A Systematic Review

OBJECTIVES

Nonunions after bone fractures are usually treated surgically with risk of infections and failure of osteosynthesis. A noninvasive alternative is extracorporeal shock wave treatment (ESWT), which potentially stimulates bone regeneration. Therefore this review investigates whether ESWT is an effective and safe treatment for delayed unions and nonunions.

DATA SOURCES

Embase.com, MEDLINE ovid, Cochrane, Web of Science, PubMed publisher, and Google Scholar were systematically searched.

STUDY SELECTION

Inclusion criteria included studies with patients with delayed union or nonunion treated with ESWT; inclusion of ≥10 patients; and follow-up period ≥6 weeks.

DATA EXTRACTION

Assessment for risk of bias was conducted by 2 authors using the Cochrane tool. Union rates and adverse events were extracted from the studies.

DATA SYNTHESIS

Two RCTs and 28 nonrandomized studies were included. One RCT was assessed at medium risk of bias and reported similar union rates between ESWT-treated patients (71%) and surgery-treated patients (74%). The remaining 29 studies were at high risk of bias due to poor description of randomization (n = 1), nonrandomized allocation to control groups (n = 2), or absence of control groups (n = 26). The average union rate after ESWT in delayed unions was 86%, in nonunions 73%, and in nonunions after surgery 81%. Only minor adverse events were reported after ESWT.

CONCLUSIONS

ESWT seems to be effective for the treatment of delayed unions and nonunions. However, the quality of most studies is poor. Therefore, we strongly encourage conducting well-designed RCTs to prove the effectiveness of ESWT and potentially improve the treatment of nonunions because ESWT might be as effective as surgery but safer.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

An investigation of shock wave therapy and low-intensity pulsed ultrasound on fracture healing under reduced loading conditions in an ovine model

The use of shock wave therapy (SWT) and low-intensity pulsed ultrasound (LIPUS) as countermeasures to the inhibited fracture healing experienced during mechanical unloading was investigated by administering treatment to the fracture sites of mature, female, Rambouillet Columbian ewes exposed to partial mechanical unloading or full gravitational loading. The amount of fracture healing experienced by the treatment groups was compared to controls in which identical surgical and testing protocols were administered except for SWT or LIPUS treatment. All groups were euthanized after a 28-day healing period. In vivo mechanical measurements demonstrated no significant alteration in fixation plate strains between treatments within either partial unloading group. Similarly, DXA BMD and 4-point bending stiffness were not significantly altered following either treatment. μCT analyses demonstrated lower callus bone volume for treated animals (SWT and LIPUS, p < 0.01) in the full gravity group but not between reduced loading groups. Callus osteoblast numbers as well as mineralized surface and bone formation rate were significantly elevated to the level of the full gravity groups in the reduced loading groups following both SWT and LIPUS. Although no increase in 4-week mechanical strength was observed, it is possible that an increase in the overall rate of fracture healing (i.e., callus strength) may be experienced at longer time points under partial loading conditions given the increase in osteoblast numbers and bone formation parameters following SWT and LIPUS. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:921-929, 2018.

Radial extracorporeal shock wave therapy is efficient and safe in the treatment of fracture nonunions of superficial bones: a retrospective case series

BACKGROUND

A substantial body of evidence supports the use of focused extracorporeal shock wave therapy (fESWT) in the non-invasive treatment of fracture nonunions. On the other hand, virtually no studies exist on the use of radial extracorporeal shock wave therapy (rESWT) for this indication.

METHODS

We retrospectively analyzed 22 patients treated with rESWT for fracture nonunions of superficial bones that failed to heal despite initial surgical fixation in most cases. Radial extracorporeal shock wave therapy was applied without anesthesia in three rESWT sessions on average, with one rESWT session per week and 3000 radial extracorporeal shock waves at an energy flux density of 0.18 mJ/mm² per session. Treatment success was monitored with radiographs and clinical examinations.

RESULTS

Six months after rESWT radiographic union was confirmed in 16 out of 22 patients (73%), which is similar to the success rate achieved in comparable studies using fESWT. There were no side effects. The tibia was the most common treatment site (10/22) and 70% of tibia nonunions healed within 6 months after rESWT. Overall, successfully treated patients showed a mean time interval of 8.8 ± 0.8 (mean ± standard error of the mean) months between initial fracture and commencement of rESWT whereas in unsuccessfully treated patients the mean interval was 26.0 ± 10.1 months (p < 0.05). In unsuccessful tibia cases, the mean interval was 43.3 ± 13.9 months.

CONCLUSIONS

Radial extracorporeal shock wave therapy appears to be an effective and safe alternative in the management of fracture nonunions of superficial bones if diagnosed early and no fESWT device is available. The promising preliminary results of the present case series should encourage the implementation of randomized controlled trials for the early use of rESWT in fracture nonunions.

Shock wave therapy of fracture nonunion

We have used the principles of extracorporeal shock wave therapy (ESWT) in the treatment of nonunion of fractures in 44 patients (49 bones).There were 35 males and 9 females with a mean age of 34 years(range14-70). Clinical and radiological assessment was performed at regular time intervals with a minimum follow up of 18 months. Most common sites involved were the femur and tibia. The average time from initial fracture treatment to intervention with ESWT was 11.9 months (6 months to 5 years). Thirty eight non-union sites had one session of treatment and the rest (11) had more than one session. Union was successful in 75.5% of cases at a mean time of 10.2 months (range 3-19). Failure in the remaining cases was due to more than 5mm gap, instability, compromised vascularity (type of bone) and deep low grade infection; which was discovered at the time of surgical intervention when no signs of radiological healing occurred after 6 months from treatment. Failing sites were shaft of femur, scaphoid, neck of humerus and neck of femur. No local complications were observed.

Extracorporeal shockwave therapy in musculoskeletal disorders

The sources of shockwave generation include electrohydraulic, electromagnetic and piezoelectric principles. Electrohydraulic shockwaves are high-energy acoustic waves generated under water explosion with high voltage electrode. Shockwave in urology (lithotripsy) is primarily used to disintegrate urolithiasis, whereas shockwave in orthopedics (orthotripsy) is not used to disintegrate tissues, rather to induce tissue repair and regeneration. The application of extracorporeal shockwave therapy (ESWT) in musculoskeletal disorders has been around for more than a decade and is primarily used in the treatment of sports related over-use tendinopathies such as proximal plantar fasciitis of the heel, lateral epicondylitis of the elbow, calcific or non-calcific tendonitis of the shoulder and patellar tendinopathy etc. The success rate ranged from 65% to 91%, and the complications were low and negligible. ESWT is also utilized in the treatment of non-union of long bone fracture, avascular necrosis of femoral head, chronic diabetic and non-diabetic ulcers and ischemic heart disease. The vast majority of the published papers showed positive and beneficial effects. FDA (USA) first approved ESWT for the treatment of proximal plantar fasciitis in 2000 and lateral epicondylitis in 2002. ESWT is a novel non-invasive therapeutic modality without surgery or surgical risks, and the clinical application of ESWT steadily increases over the years. This article reviews the current status of ESWT in musculoskeletal disorders.

Effects of extracorporeal shock wave therapy and polysulfated glycosaminoglycan treatment on subchondral bone, serum biomarkers, and synovial fluid biomarkers in horses with induced osteoarthritis

OBJECTIVE

To evaluate effects of extracorporeal shock wave therapy (ESWT) and polysulfated glycosaminoglycan treatment (PSGAGT) on subchondral bone (SCB), serum biomarkers, and synovial fluid biomarkers in horses with induced osteoarthritis.

ANIMALS

24 healthy 2- to 3-year-old horses.

PROCEDURES

An osteochondral fragment was created on the distal aspect of the radial carpal bone in 1 middle carpal joint of each horse. Horses were randomly allocated to receive local application of ESWT (days 14 and 28; n = 8), PSGAGT (IM, q 4 d for 28 days; 8), or a sham ESWT probe (placebo; days 14 and 28; 8). Serum biomarkers were measured every 7 days, and synovial fluid biomarkers were measured every 14 days. Bone density was measured by use of computed tomography on days 0 and 70, and microdamage and bone formation variables were compared among groups at the end of the study (day 70).

RESULTS

There was no significant effect of ESWT or PSGAGT on any bone variable. Serum osteocalcin concentration was significantly greater in horses that received ESWT, compared with placebo-treated horses, and serum concentration of the C-terminal telopeptide of type I collagen was significantly higher in horses that received ESWT, compared with placebo- and PSGAG-treated horses. Concentrations of the synovial fluid epitope CS846 were significantly higher in joints with osteoarthritis treated with ESWT CONCLUSIONS AND CLINICAL RELEVANCE: Treatment of osteoarthritis with ESWT had no effect on SCB but did induce increases in serum biomarkers indicative of bone remodeling. Treatment of osteoarthritis with PSGAG had no effect on SCB or biomarkers.

Development of a prognostic naive bayesian classifier for successful treatment of nonunions

BACKGROUND

predictive models permitting individualized prognostication for patients with fracture nonunion are lacking. The objective of this study was to train, test, and cross-validate a Bayesian classifier for predicting fracture-nonunion healing in a population treated with extracorporeal shock wave therapy.

METHODS

prospectively collected data from 349 patients with delayed fracture union or a nonunion were utilized to develop a naïve Bayesian belief network model to estimate site-specific fracture-nonunion healing in patients treated with extracorporeal shock wave therapy. Receiver operating characteristic curve analysis and tenfold cross-validation of the model were used to determine the clinical utility of the approach.

RESULTS

predictors of fracture-healing at six months following shock wave treatment were the time between the fracture and the first shock wave treatment, the time between the fracture and the surgery, intramedullary stabilization, the number of bone-grafting procedures, the number of extracorporeal shock wave therapy treatments, work-related injury, and the bone involved (p < 0.05 for all comparisons). These variables were all included in the naïve Bayesian belief network model.

CONCLUSIONS

a clinically relevant Bayesian classifier was developed to predict the outcome after extracorporeal shock wave therapy for fracture nonunions. The time to treatment and the anatomic site of the fracture nonunion significantly impacted healing outcomes. Although this study population was restricted to patients treated with shock wave therapy, Bayesian-derived predictive models may be developed for application to other fracture populations at risk for nonunion.

LEVEL OF EVIDENCE

prognostic Level II. See Instructions to Authors for a complete description of levels of evidence.

Shock wave therapy as a treatment of nonunions, avascular necrosis, and delayed healing of stress fractures

Shock wave therapy (SWT) stimulates angiogenesis and osteogenesis. SWT is commonly used to treat soft tissue musculoskeletal conditions such as fasciopathies and tendinopathies. Recent basic science and clinical data suggest that SWT can also be used to treat disorders of bone. Nonunions, avascular necrosis, and delayed healing of stress fractures have all been successfully treated with SWT. Success rates with SWT are equal to those with standard surgical treatment, but SWT has the advantage of decreased morbidity. The procedure is safe, well tolerated, yields few complications, and, typically, can be performed on an outpatient basis. SWT is a viable noninvasive alternative to stimulate healing of bone.

Bone morphogenetic protein-2 expression in spinal fusion masses enhanced by extracorporeal shock wave treatment: a rabbit experiment

PURPOSE

Extracorporeal shock wave (ESW) has been introduced to enhance spinal fusion. This study was conducted to assess the effect of ESW on bone morphogenetic protein-2 (BMP-2) expression in a spinal fusion experiment.

METHODS

Twelve rabbits underwent fusion at bilateral L5-6 intertransverse spaces. They were evenly divided into two groups. In the study group, bilateral L5 and L6 transverse processes were treated with 1,000 impulses of ESW at 14 kV at 12 weeks. In the control group, the rabbits did not receive ESW treatment. All rabbits were sacrificed at 16 weeks, and their lumbar spines were harvested for radiographic and molecular biological study.

RESULTS

In the study group (n = 6), the radiographs showed good fusion in all six rabbits, while in the control group (n = 6), good fusion was found only in three rabbits (50%). Although more rabbits in the study group had a good fusion result, the inter-group difference was not statistically significant (P = 0.182). In the molecular biological examination, the mean value of the normalized expression of BMP-2 mRNA in the fusion masses of the study group was 90 ± 8.4 while that of the control group was 77.33 ± 6.74. Statistical analysis showed the study group had a significantly higher BMP-2 mRNA expression in the fusion masses than the control group (P = 0.018).

CONCLUSIONS

The current study showed that ESW treatment enhances BMP-2 mRNA expression in spinal fusion masses.

Extracorporeal shockwaves versus surgery in the treatment of pseudoarthrosis of the carpal scaphoid

The peculiar anatomical characteristics and precarious vascularization of the carpal scaphoid are responsible for a difficult healing of fractures and a fairly frequent subsequent evolution to pseudoarthrosis. Recently, extracorporeal shockwaves therapy (ESWT) has yielded encouraging results in the treatment of pseudoarthrosis of various bone segments. We report a retrospective study comparing the results of application of three sessions of shockwaves therapy (SW) with energy flux density (EFD) impulses of 0.09 (SD = 0.02) mJ/mm(2) ESWT emitted by an electromagnetic generator in 58 patients (group I) affected by pseudoarthrosis of the carpal scaphoid, with the results of surgical treatment consisting of stabilization and bone graft according to the Matti-Russe technique, performed in 60 subjects (controls, group II). There were no statistically significant differences in the mean duration of the pseudoarthrosis (p = 0.46), sex distribution (p = 0.41) and mean age at recruitment (p = 0.95) between the two patient groups. Posttreatment clinical-functional assessment, based on the Mayo Wrist Score, showed a significantly improved score, rising from 28-74.6 in group I already after 2 mo (p < 0.001), with 86.3% of the results judged as satisfactory or excellent; in group II the mean score rose from 27.5-74.2 after 2 mo, with 83.4% of the results judged as satisfactory or excellent (p < 0.001). At the same two-months follow-up (FU), radiographic consolidation was shown in 75.9% of patients in group I and 76.7% in group II. These improvements persisted at the subsequent controls at six and 12 mo in both groups. The Mayo Wrist Score and X-rays did not show statistically significant differences at the various FU visits in the two groups (p > 0.05). On the basis of our data, we can conclude that the results of ESWT are comparable with those of surgical stabilization and bone graft in the treatment of scaphoid pseudoarthrosis. In view of their minimal invasiveness, shockwaves should therefore be considered the treatment of choice of this disorder.

Extracorporeal shock wave therapy: current evidence

OBJECTIVES

The aim of this article is to provide a concise review of the basic science of extracorporeal shock wave therapy (ESWT) and to perform a systematic review of the literature for the use of ESWT in the treatment of fractures and delayed unions/nonunions.

DATA SOURCES

Articles in the English or German language were identified for the systematic review by searching PubMed-MEDLINE from 1966 until 2008, Cochrane Database of Systematic Reviews, Cochrane Database of Abstracts of Reviews of Effects, Cochrane Central Register of Controlled Trials, and relevant meeting abstracts from 2007 to 2008. Moreover, the bibliographies of the identified articles were reviewed.

STUDY SELECTION

We included clinical outcome studies of ESWT in the treatment of fractures and delayed unions/nonunions. Reports with less than 10 patients were excluded. Nonunions after corrective osteotomies or arthrodeses were excluded.

DATA EXTRACTION

Sample size, level of evidence, definition of delayed union, definition of nonunion, time from injury to shock wave treatment, location of fracture, union rate, and complications were extracted from the identified articles.

DATA SYNTHESIS

Data of 924 patients undergoing ESWT for delayed union/nonunion were extracted from 10 studies. All articles were graded as level 4 studies. The overall union rate was 76% (95% confidence interval 73%-79%). The union rate was significantly higher in hypertrophic nonunions than in atrophic nonunions.

CONCLUSION

Data from level 4 studies suggest that shock wave therapy seems to stimulate the healing process in delayed unions/nonunions. However, further investigations are required.

Extracorporeal shock wave therapy for nonunion of the tibia

OBJECTIVES

Delayed and nonunion of the tibia are not uncommon in orthopaedic practice. Multiple methods of treatment have been developed with variable results. The objective of this study was to define disease-specific and treatment-related factors of prognostic significance in patients undergoing shock wave therapy for tibia nonunion.

DESIGN

Retrospective analysis.

PATIENTS

One hundred ninety-two patients treated with extracorporeal shock wave therapy (ESWT) at a single referral trauma center, AUVA-Trauma Center Meidling, a large single-referral trauma center located in Vienna, Austria, in an attempt to determine the feasibility and factors associated with the use of ESWT in the treatment for tibia nonunion.

INTERVENTION

ESWT coupled with posttreatment immobilization, external fixation, or ESWT alone.

MAIN OUTCOME MEASURES

Fracture healing, overall healing percent, and factors associated with ESWT success or failure.

RESULTS

At the time of last follow up, 138 of 172 (80.2%) patients have demonstrated complete fracture healing. Mean time from first shock wave therapy to complete healing of the tibia nonunion was 4.8+/-4.0 months. Number of orthopaedic operations (P=0.003), shock wave treatments (P=0.002), and pulses delivered (P=0.04) were significantly associated with complete bone healing. Patients requiring multiple (more than one) shock wave treatments versus a single treatment had a significantly lower likelihood of fracture healing (P=0.003). This may be attributable to the finding that a significantly greater proportion of patients with multiple rather than single ESWT treatments had three or more prior orthopaedic procedures (more than one ESWT, 63.9% versus one ESWT, 23.5%; P<0.001).

CONCLUSIONS

ESWT is a feasible treatment modality for tibia nonunion.

Primary Osteoblasts Response to Shock Wave Therapy Using Different Parameters

Over the past decade extracorporeal shock-wave therapy (ESWT) has been increasingly applied to orthopaedic and musculoskeletal pathologies, the aim of this study was to assess how the energy density of the shock waves and the number of impulses affect viability, differentiation and synthetic activity of osteoblasts. Primary sheep osteoblasts cultures were treated with ESWT with an electro-hydraulic shock wave generator by selecting three different energy levels (14-21-28 kV corresponding at 0.15-0.31-0.40 mJ/mm2) and two different total numbers of impulses (500, 1000) for each level. At the end of treatment, cell counts and viability were recorded. Cells were then cultivated for 48 hours starting from a concentration of 1 x 10(4) cells/ml. The biological activity and viability were evaluated at 24 and 48 hours after treatment. No cytodestructive effects were observed in Group A, while a cytodestructive effect of ESWT was seen in cultures receiving the highest energy treatments. The different shock wave treatment induced differences in MTT assays after 24 and 48 hours, in particular the highest level showed a detrimental effect on cell respiration at both experimental times as compared to the Control Group and the protein metabolism was generally depressed by ESWT with impulses at the highest energy level. After 24 hours such effect further increased with the growing number of impulses. The lowest energy level appeared to significantly improve the metabolic parameter in primary cell cultures as compared to controls when 500 impulses were selected. The current study has demonstrated that one of the most important aspects to be considered is not the total number of impulses used but the energy level of the shock waves, thus confirming that ESWT has a dose-dependent effect on cells.

Extracorporeal shockwave therapy: A systematic review of its use in fracture management

Extracorporeal shockwave therapy is increasingly used as an adjuvant therapy in the management of nonunions, delayed unions and more recently fresh fractures. This is in an effort to increase union rates or obtain unions when fractures have proven recalcitrant to healing. In this report we have systematically reviewed the English language literature to attempt to determine the potential clinical efficacy of extracorporeal shockwave therapy in fracture management. Of 32 potentially eligible studies identified, 10 were included that assessed the extracorporeal shockwave therapy use for healing nonunions or delayed unions, and one trial was included that assessed its use for acute high-energy fractures. From the included, studies' overall union rates were in favor of extracorporeal shockwave therapy (72% union rate overall for nonunions or delayed unions, and a 46% relative risk reduction in nonunions when it is used for acute high-energy fractures). However, the methodologic quality of included studies was weak and any clinical inferences made from these data should be interpreted with caution. Further research in this area in the form of a large-scale randomized trial is necessary to better answer the question of the effectiveness of extracorporeal shockwave therapy on union rates for both nonunions and acute fractures.

Treatment of osteonecrosis of the hip: comparison of extracorporeal shockwave with shockwave and alendronate

BACKGROUND AND PURPOSE

Extracorporeal shockwave therapy (ESWT) and alendronate are reported effective in early osteonecrosis of the femoral head (ONFH). We hypothesized that joint effects of ESWT and alendronate may produce superior results. This prospective study compared the results of ESWT and alendronate with that of ESWT without alendronate in early ONFH.

PATIENTS AND METHODS

Forty-eight patients with 60 hips were randomly divided into tow groups. There were 25 patients with 30 hips in group A and 23 patients with 30 hips in group B. Both groups showed similar demographic characteristics. All patients were treated with 6,000 impulses of ESWT at 28 KV (equivalent to 0.62 mJ/mm(2)) to the affected hip as a single session. Patients in group B also received alendronate 70 mg per week for 1 year, whereas patients in group A did not. The evaluations included clinical assessment, radiograph and MR image of the affected hip. Both groups were compared statistically using paired t, Mann-Whitney and Chi square tests with statistical significance at P < 0.05. The primary end point is the need for total hip arthroplasty (THA). The secondary end point is the improvement in pain and function of the hip. The third end point is the progression or regression of the lesion on image study.

RESULTS

The overall clinical outcomes were improved in 83%, unchanged in 7% and worsened in 10% for group A; and improved in 77%, unchanged in 13% and worsened in 10% for group B. THA was performed in 10% of group A and 10% of group B (P = 1.000). Significant improvements in pain and function of the hip were noted in both groups (P < 0.001), however, the differences between the two groups were not significant (P = 0.400, 0.313). On MR images, the lesions showed progression in 10%, regression in 47% and unchanged in 43% in group A, and progression in 7%, regression in 53% and unchanged in 40% in group B (P = 0.830).

CONCLUSION

ESWT and alendronate produced comparable result as compared with ESWT without alendronate in early ONFH. It appears that ESWT is effective with or without the concurrent use of alendronate. The joint effects of alendronate over ESWT in early ONFH are not realized in short-term.

Biological effects of extracorporeal shockwave in bone healing: a study in rabbits

INTRODUCTION

This study is an investigation of the biological effects of extracorporeal shockwave treatment (ESWT) on bone healing in a rabbit model.

MATERIALS AND METHODS

Sixteen 12-month-old New Zealand white rabbits with body weight ranging from 2.5 to 3.5 kg were used in the study. An intra-medullary pin was inserted retrograde into the femur canal. A closed fracture of the femur was created with a three-point bend method. The animals were randomly divided into the study group and the control group with eight rabbits in each group. The study group received shockwave treatment, whereas the control group did not. The animals were killed at 12 weeks, and a 5-cm long femur bone including the callus was harvested. The specimens were subjected to biomechanical study, histomorphological examination, and immunohistochemical analysis.

RESULTS

The shockwave group showed significantly better bone strength in biomechanical study, more cortical bone formation in histomorphological examination and higher number of neo-vessels and angiogenic and osteogenic growth markers including VEGF, eNOS, PCNA, and BMP-2 on immunohistochemical stains than the control group.

CONCLUSION

ESWT significantly improved bone healing after fracture of the femur in rabbit. ESWT promoted the formation of cortical bone what might have been associated with increased biomechanical results. ESWT-promoted bone healing was associated with increased neovascularization and up-regulation of angiogenic and osteogenic growth factors.

Shock wave therapy for acute and chronic soft tissue wounds: a feasibility study

BACKGROUND

Nonhealing wounds are a major, functionally-limiting medical problem impairing quality of life for millions of people each year. Various studies report complete wound epithelialization of 48 to 56% over 30 to 65 d with different treatment modalities including ultrasound, topical rPDGF-BB, and composite acellular matrix. This is in contrast to comparison control patients treated with standard wound care, demonstrating complete epithelialization rates of 25 to 39%. Extracorporeal shock wave therapy (ESWT) may accelerate and improve wound repair. This study assesses the feasibility and safety of ESWT for acute and chronic soft-tissue wounds.

STUDY DESIGN

Two hundred and eight patients with complicated, nonhealing, acute and chronic soft-tissue wounds were prospectively enrolled onto this trial between August 2004 and June 2006. Treatment consisted of debridement, outpatient ESWT [100 to 1000 shocks/cm(2) at 0.1 mJ/mm(2), according to wound size, every 1 to 2 wk over mean three treatments], and moist dressings.

RESULTS

Thirty-two (15.4%) patients dropped out of the study following first ESWT and were analyzed on an intent-to-treat basis as incomplete healing. Of 208 patients enrolled, 156 (75%) had 100% wound epithelialization. During mean follow-up period of 44 d, there was no treatment-related toxicity, infection, or deterioration of any ESWT-treated wound. Intent-to-treat multivariate analysis identified age (P = 0.01), wound size < or =10 cm(2) (P = 0.01; OR = 0.36; 95% CI, 0.16 to 0.80), and duration < or =1 mo (P < 0.001; OR = 0.25; 95% CI, 0.11 to 0.55) as independent predictors of complete healing.

CONCLUSIONS

The ESWT strategy is feasible and well tolerated by patients with acute and chronic soft tissue wounds. Shock wave therapy is being evaluated in a Phase III trial for acute traumatic wounds.

Vulnerability of the spinal cord to injury from extracorporeal shock waves in rabbits

We studied the vulnerability of the spinal cord to extracorporeal shock wave treatment (ESWT). In this experiment, 12 rabbits were divided into three groups (4 in each group). All animals underwent a preceding lumbar laminectomy at L4 1 week before ESWT. In group 1, 2000 impulses of high dose (0.62 mJ/mm2 energy flux density) shockwave energy were applied to the spinal cord at the laminectomy site. In group 2, 2000 impulses of low dose (0.18 mJ/mm2 energy flux density) shockwave energy were applied to the same site as group 1. Group 3 did not receive ESWT and served as a control. None of the rabbits in the study groups (groups 1 and 2) showed weakness or paralysis of the hind limbs throughout the entire post-ESWT period. The spinal cord at the L4 level of all animals was harvested on day 13 after laminectomy. On gross morphology, the cord from the study groups and the control group showed normal surface appearance. On microscopic examination, the cord from the control group was normal, whereas the cords from the study groups showed varying degrees of myelin damage and neuronal loss. These microscopic findings were dose-dependent. For the low-energy group (group 2), neuronal loss was insignificant compared to that in the control group. ESWT produced varying degrees of microscopic changes of the treated cords, but no neurological symptoms. The neuronal injury was dose-dependent and mild in the low-energy group.

Upregulation of VEGF in subchondral bone of necrotic femoral heads in rabbits with use of extracorporeal shock waves

Extracorporeal shock wave treatment appears to be effective in patients with avascular necrosis of the femoral head. However, the pathway of biological events whereby this is accomplished has not been fully elucidated. The purpose of this study was to investigate the effect of extracorporeal shock waves on vascular endothelial growth factor (VEGF) expression in necrotic femoral heads of rabbits. VEGF expression was assessed by immunohistochemistry, quantitative real-time PCR, and Western blot analysis. The degree of angiogenesis was also assessed, as determined by the microvessel density (MVD), the assessment of which was based on CD31-expressing vessels. Bilateral avascular necrosis of femoral heads was induced with methylprednisolone and lipopolysaccharide in 30 New Zealand rabbits. The left limb (the study side) received shock wave therapy to the femoral head. The right limb (the control side) received no shock wave therapy. Biopsies of the femoral heads were performed at 1, 2, 4, 8, and 12 weeks. Western blot analysis and real-time PCR showed that shock wave therapy significantly increased VEGF protein and mRNA expression, respectively, in the subchondral bone of the treated necrotic femoral heads. Compared with the contralateral control without shock wave treatment, the VEGF mRNA expression levels increased to a peak at 2 weeks after the shock wave treatment and remained high for 8 weeks, then declined at 12 weeks, whereas the VEGF protein expression levels increased to a peak at 4 weeks after the shock wave treatment and remained high for 12 weeks. The immunostaining of VEGF was weak in the control group, and the immunoreactivity level in the shock-wave-treated group increased at 4 weeks and persisted for 12 weeks. The most intensive VEGF immunoreactivity was observed in the proliferative zone above the necrotic zone. At 4, 8, and 12 weeks after the shock wave treatment, MVD in subchondral bone from treated femoral heads was significantly higher than that in subchondral bone from untreated femoral heads. These data clearly show that extracorporeal shock waves can significantly upregulate the expression of VEGF. The upregulation of VEGF may play a role in inducing the ingrowth of neovascularization and in improving the blood supply to the femoral head.

The effects of extracorporeal shockwave on acute high-energy long bone fractures of the lower extremity

INTRODUCTION

High-energy long bone fractures of the lower extremity are at risk of poor fracture healing and high rate of non-union. Extracorporeal shockwave was shown effective to heal non-union of long bone fracture. However, the effect of shockwave on acute fractures is unknown. The purpose of this study was to investigate the effects of shockwave on acute high-energy fractures of the lower extremity.

MATERIALS AND METHODS

Between January and October 2004, 56 patients with 59 acute high-energy fractures were enrolled in this study. Patients were randomly divided into two groups with 28 patients with 28 fractures in the study group and 28 patients with 31 fractures in the control group. Both groups showed similar age, gender, type of fracture and follow-up time. Patients in the study group received open reduction and internal fixation and shockwave treatment immediately after surgery on odd-numbered days of the week, whereas, patients in the control group received open reduction and internal fixation without shockwave treatment on even-numbered days of the week. Postoperative managements were similarly performed in both groups including crutch walking with non-weight bearing on the affected limb until fracture healing shown on radiographs. The evaluation parameters included clinical assessments of pain score and weight bearing status of the affected leg and serial radiographs at 3, 6 and 12 months. The primary end-point is the rate of non-union at 12 months, and the secondary end point is the rate of fracture healing at 3, 6 and 12 months.

RESULTS

At 12 months, the rate of non-union was 11% for the study group versus 20% for the control group (P < 0.001). Significantly, better rate of fracture healing was noted in the study group than the control group at 3, 6 and 12 months (P < 0.001).

CONCLUSION

Extracorporeal shockwave is effective on promoting fracture healing and decreasing the rate of non-union in acute high-energy fractures of the lower extremity.

Early Effects of Extracorporeal Shock Wave Treatment on Osteoblast-like Cells: A Comparative Study Between Electromagnetic and Electrohydraulic Devices

BACKGROUND

Extracorporeal shockwave therapy (ESWT) has been increasingly applied to treat orthopedic and musculoskeletal pathologies. ESWT involves mechanical perturbations that, as with other physical therapies, can result in mechanical stimuli to a large number of cells, including bone cells. The aim of this study was to evaluate the effects of shock waves on osteoblast-like cells (MG63) when using two different generators of shock waves (electrohydraulic and electromagnetic devices), in terms of cell damage, cell viability, osteogenic phenotype expression, and cytokine production.

METHODS

MG63 cells were suspended in 1.5 mL screw-cap cryotubes (1 x 10 cells/mL), containing phosphate buffer solution (PBS), which were maintained at 37 degrees C during all the experimental times. Two levels of energy flux density (EFD) were evaluated for each device: 0.15 to 0.18 mJ/mm2 and 0.40 mJ/mm2. Cells were then cultivated for 72 hours starting from a concentration of 1 x 10 cells/mL, and biological activity and viability were evaluated 24 and 72 hours after treatment.

RESULTS

The results obtained demonstrate that the factors most affecting osteoblast activity involve both the device and the level of EFD selected, and they must be considered all together.

CONCLUSIONS

The use of the electromagnetic device and a level of EFD lower than 0.40 mJ/mm2 would appear to induce fewer immediate cytodestructive effects and better stimulate subsequent proliferation and the synthetic activity of MG63.

Feasibility of percutaneous gene transfer to an atrophic nonunion in a rabbit

Treatment of atrophic nonunions is a challenge to orthopaedic surgeons. Growth factors potentially are valuable factors for improvement of tissue healing. The use of growth factors, however, is limited by their short half-lives. Gene therapy has the potential to improve the treatment. This study aimed to establish and validate an atrophic nonunion model in a rabbit for the use of a percutaneous in vivo gene therapy protocol. An atrophic tibial nonunion was established in 24 New Zealand White rabbits. Radiologic and histologic followup was for 64 weeks. The rabbit tibias showed no radiologic or histologic signs of healing. In addition, an adenoviral vector carrying a marker gene was injected percutaneously into the nonunion site in 12 rabbits. Expression of the marker gene was assessed for as many as 4 weeks. The percutaneous gene delivery resulted in transgene expression in the nonunion site for as many as 4 weeks. The described model reliably leads to an atrophic tibial nonunion in rabbits. Adenoviral percutaneous gene delivery into the nonunion site is feasible and leads to transgene expression locally for at least 1 month. This study provides investigators with a reliable and reproducible model of an atrophic nonunion.

Shock wave treatment shows dose-dependent enhancement of bone mass and bone strength after fracture of the femur

Shock wave treatment is believed to improve bone healing after fracture. The purpose of this study was to evaluate the effect of shock wave treatment on bone mass and bone strength after fracture of the femur in a rabbit model. A standardized closed fracture of the right femur was created with a three-point bending method in 24 New Zealand white rabbits. Animals were randomly divided into three groups: (1) control (no shock wave treatment), (2) low-energy (shock wave treatment at 0.18 mJ/mm2 energy flux density with 2000 impulses), and (3) high-energy (shock wave treatment at 0.47 mJ/mm2 energy flux density with 4000 impulses). Bone mass (bone mineral density (BMD), callus formation, ash and calcium contents) and bone strength (peak load, peak stress and modulus of elasticity) were assessed at 12 and 24 weeks after shock wave treatment. While the BMD values of the high-energy group were significantly higher than the control group (P = 0.021), the BMD values between the low-energy and control groups were not statistically significant (P = 0.358). The high-energy group showed significantly more callus formation (P < 0.001), higher ash content (P < 0.001) and calcium content (P = 0.003) than the control and low-energy groups. With regard to bone strength, the high-energy group showed significantly higher peak load (P = 0.012), peak stress (P = 0.015) and modulus of elasticity (P = 0.011) than the low-energy and control groups. Overall, the effect of shock wave treatment on bone mass and bone strength appears to be dose dependent in acute fracture healing in rabbits.

Effect of extracorporeal shock wave therapy on osteoblastlike cells

Extracorporeal shock wave therapy has been used increasingly in musculoskeletal disorders although its biologic mechanisms are not understood completely. The current study evaluated the effects of extracorporeal shock wave therapy on human osteoblastlike cells by using an electrohydraulic shock wave generator and comparing three energy levels. (Group A, 14 kV and 0.15 mJ/mm2; Group B, 21 kV and 0.31 mJ/mm2; Group C, 28 kV and 0.40 mJ/mm2; Control Group, no energy) and two total impulses (500, 1000) for each level. At the end of treatment, a reduction by approximately 76% was observed in Group C cell number versus basal value when compared with the other groups. Viability, biochemical activity, and gene expression of cultured cells were evaluated 24 and 48 hours after treatment. The viability test showed a decrease in Group C viability of approximately 54% at both culture times as compared with the other groups. Significant increases in nitric oxide, osteocalcin, and transforming growth factor-beta1 production ranging from 10% to 35% were found in Group A. All treated groups had lower C-terminal procollagen Type I values than the Control Group, but important increases were observed between 24 and 48 hours in all groups except Group C. This particular finding reveals that osteoblast differentiation in Group A is enhanced strongly during the first 24 hours after exposure leading after another 24 hours to an increase in C-terminal procollagen Type I production and consequently in bone matrix deposition. The current study showed that one of the most important aspects to be considered is not the total number of impulses used, but the energy level of the shock waves, therefore confirming that extracorporeal shock wave therapy has a dose-dependent initial destructive effect on cells when the selected energy is higher than 21 kV.

Extracorporeal shock waves in the treatment of nonunions

BACKGROUND

Nonunion remains a major complication after skeletal trauma. In the last decade, extracorporeal shock wave therapy has become a common tool for the treatment of nonunions. To date, no prospective, randomized trial has been conducted to show the efficacy of this form of treatment.

METHODS

This study was performed to determine the value of extracorporeal shock wave therapy for nonunions. Previous published results in the literature and our own clinical results were analyzed and related to the natural history of bony union.

RESULTS

No study has proven that extracorporeal shock wave therapy improves bone healing. Clinical studies reporting the acceleration of union after application of shock waves instead seem to misinterpret the natural history of bony union.

CONCLUSION

No evidence supports the treatment of pseudarthroses with extracorporeal shock waves. A randomized, prospective, clinical trial with a control group has to be performed before a final decision can be made regarding this indication for extracorporeal shock wave therapy.

Short-time non-enzymatic nitric oxide synthesis from L-arginine and hydrogen peroxide induced by shock waves treatment

The evidence that nitric oxide (NO) production is possible by a non-enzymatic pathway has already been shown under restrictive experimental conditions. Here we show that NO can non-enzymatically be formed with short-time kinetics (min), by 'bombing' with shock waves a solution containing 1 mM hydrogen peroxide and 10 mM L-arginine. This procedure is widening its medical application with surprisingly positive effects in tissue regeneration and our finding could be one of the first steps for the understanding of the biochemical responsible for these therapeutical effects.

Pathomechanism of shock wave injuries on femoral artery, vein and nerve. An experimental study in dogs

PURPOSE

To study the pathomechanism of shock wave injuries to the femoral artery, vein and nerve in dogs.

MATERIALS AND METHODS

High-energy shock wave (0.47 mJ/mm(2) energy flux density) were applied to the right femoral artery, vein and nerve in nine mongrels, and the left side was used as control. Macroscopic examinations including structure integrity, edema, discolouration and extravasation; and microscopic examinations including detachment of the intima layer, disruption of the medium layer, capillary congestion, neutrophil margination and extravasation of the outer layer and the surrounding tissues were performed in 2 h, and in 4 days, respectively, after shock wave application.

RESULTS

The most serious injuries included disruption of the medium layer with separation from the adventitia layer of the femoral artery. The injuries to the femoral vein and nerve predominantly involved the outer adventitia layer and the surrounding tissues. Mild nerve bundle swelling was noted in most cases. There were capillary congestion, neutrophil margination and extravasation indicative of inflammatory tissue reaction after shock wave application.

CONCLUSION

High-energy shock waves caused serious injuries to the femoral artery, vein and nerve, especially the femoral artery and inflammatory reaction to the surrounding tissues.

High-energy shock wave treatment of femoral head necrosis in adults

Adults with Stages I to III osteonecrosis of the femoral head present an overall therapeutic challenge. The objective of the current prospective study was to show the effectiveness of high-energy shock wave therapy in treatment of patients with Association Research Circulation Osseous Stage I to Stage III necrosis of the femoral head by assessing clinical and magnetic resonance imaging results. The current study presents the results of 22 patients with femoral head necrosis 1 year after shock wave treatment. The study population consisted of 10 women and 12 men with an average age of 54.9 years (+/- 12.3). The scores achieved on the visual pain analog scale decreased from 8.5 before treatment to 1.2 after 1 year. Simultaneously, the Harris hip score increased from 43.3 to 92 points. Magnetic resonance imaging visualization of a distinct zone of sclerosis around the necrotic area remaining after treatment with extracorporeal shock wave therapy indicated therapeutic failure. The results obtained so far with high-energy shock wave therapy in these patients suggest that this method may offer an alternative to invasive treatment modalities for femoral head necrosis. A noninvasive and moderately priced method then would be available for the treatment of femoral head necrosis in the early stages of the disease process.

New-generation lithotripters for treatment of patients with implantable cardioverter defibrillator: experimental approach and review of literature

PURPOSE

The influence of shockwaves applied during extracorporeal shockwave lithotripsy on the function of implantable cardioverter defibrillators was evaluated. Mechanical influences as well as proper electrical function were tested in an experimental approach.

MATERIALS AND METHODS

Two implantable defibrillators (Ventak Mini 1743 and AVII 1821) were exposed to the shockwaves of a new-generation lithotripter. Each of the antidysrhythmic devices was tested at several distances from and within the focus of the lithotripter. All studies were performed with maximum energy and the number of shockwaves used for stone treatment. The devices were connected to an ECG simulator, and continuous recording of a surface ECG, a shock ECG, and marker channel was performed.

RESULTS

No macroscopic and microscopic mechanical damage was observed. The detection function of the implantable defibrillators was not altered by any electromagnetic artifacts even when brought into the focus of the shockwaves. All induced ventricular dysrhythmias were terminated properly regarding artifact sensing. However, after defibrillation, the pacing function of the Ventak Mini cardioverter defibrillator, which was programmed into the demand mode, failed. In this case, there was no post-shock pacing in the period of post-defibrillation asystole. The failure was caused by artifact oversensing.

CONCLUSION

In patients with implanted cardiac devices undergoing treatment with a new-generation lithotripter, deactivation of the defibrillator is not mandatory. For safety reasons, continuous ECG recording is recommended. To avoid pacing failure by artifact oversensing, the shockwaves should be applied in a R-wave synchronous mode.

Effect of shock wave therapy on acute fractures of the tibia: a study in a dog model

The effect of shock wave therapy on acute fractures of the tibia was studied in eight adult dogs. A fracture with a 3-mm gap was created in both tibias and the fractures were fixed internally with a small metallic plate and screws. Each of the right limbs received 2,000 impulses of shock waves at 14 kV whereas the left limbs were used as controls. The evaluations included the callus formations based on serial radiographic examinations at 1, 4, 8, and 12 weeks and histologic examinations at 12 weeks for tissue distribution including bone tissues. Based on radiographic findings, there was no statistically significant difference in the amount of callus formation between the treated and the control groups at 8 weeks or less. However, the radiographic findings at 12 weeks statistically showed more callus formations in the treated group. In histologic examinations, there was significantly more cortical bone formation in the treated group at 12 weeks and the bone tissues were thicker, denser, and heavier. Shock wave therapy enhanced callus formation and induced cortical bone formation in acute fractures in dogs at 12 weeks. The effect of shock wave therapy seemed to be time-dependent at 3 months.

Treatment of nonunions of long bone fractures with shock waves

A prospective clinical study investigated the effectiveness of shock waves in the treatment of 72 patients with 72 nonunions of long bone fractures (41 femurs, 19 tibias, seven humeri, one radius, three ulnas and one metatarsal). The doses of shock waves were 6,000 impulses at 28 kV for the femur and tibia, 3,000 impulses at 28 kV for the humerus, 2,000 impulses at 24 kV for the radius and ulna, and 1,000 impulses at 20 kV for the metatarsal. The results of treatment were assessed clinically, and fracture healing was assessed with plain radiographs and tomography. The rate of bony union was 40% at 3 months, 60.9% at 6 months, and 80% at 12 months followup. Shock wave treatment was most successful in hypertrophic nonunions and nonunions with a defect and was least effective in atrophic nonunions. There were no systemic complications or device-related problems. Local complications included petechiae and hematoma formation that resolved spontaneously. In the authors' experience, the results of shock wave treatment were similar to the results of surgical treatment for chronic nonunions with no surgical risks. Shock wave treatment is a safe and effective alternative method in the treatment of chronic nonunions of long bones.

Shock wave therapy (Orthotripsy) in musculoskeletal disorders

Extracorporeal shock wave therapy, which now is used routinely for urolithiasis, has gained increasing acceptance in Europe for some musculoskeletal problems and has led to the inception of clinical studies in the United States. The authors have reviewed the available literature to assess the biologic effects of shock waves on human musculoskeletal tissues, the credibility of published studies on therapeutic applications, and the potential for more widespread application of this modality to various skeletal and near-skeletal disorders. The primary advantage of extracorporeal shock wave therapy is its noninvasive nature and seemingly minimal complications when applied to musculoskeletal tissues.