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

Outcomes Using Focused Shockwave for Treatment of Bone Stress Injury in Runners

Bone stress injury (BSI) is a common overuse injury that can result in prolonged time away from sport. Limited studies have characterized the use of extracorporeal shockwave therapy (ESWT) for the treatment of BSI. The purpose of this study was to describe the use of ESWT for the management of BSI in runners. A retrospective chart review was performed to identify eligible patients in a single physician's clinic from 1 August 2018 to 30 September 2022. BSI was identified in 40 runners with 41 injuries (28 females; average age and standard deviation: 30 ± 13 years; average pre-injury training 72 ± 40 km per week). Overall, 63% (n = 26) met the criteria for moderate- or high-risk Female or Male Athlete Triad categories. Runners started ESWT at a median of 36 days (IQR 11 to 95 days; range 3 days to 8 years) from BSI diagnosis. On average, each received 5 ± 2 total focused ESWT treatments. Those with acute BSI (ESWT started <3 months from BSI diagnosis) had an average return to run at 12.0 ± 7.5 weeks, while patients with delayed union (>3 months, n = 3) or non-union (>6 months, n = 9) had longer time for return to running (19.8 ± 14.8 weeks, p = 0.032). All runners returned to pain-free running after ESWT except one runner with non-union of grade 4 navicular BSI who opted for surgery. No complications were observed with ESWT. These findings suggest that focused ESWT may be a safe treatment for the management of BSI in runners.

Stress Injuries in the Athlete

Stress fractures are a common injury that present in athletes because of the high intensity and repetitive nature of many sports. These injuries require a high index of suspicion in the treating clinician to allow for timely management. Though most low-risk fractures heal well with conservative management, high-risk stress fractures as well as any fracture in the elite athlete may warrant surgical intervention as well as an augmented treatment and rehabilitation regimen.

Extracorporeal shock wave treatment in foot and ankle fracture non-unions - A review

BACKGROUND

The authors reviewed the current evidence and conducted a comprehensive review on the use of extracorporeal shock wave therapy (ESWT) in the treatment of foot and ankle fracture non-unions.

METHODS

Four databases were searched to identify relevant studies in the available literature.

RESULTS

Eight studies were reviewed, demonstrating union rates of 65%-100% and 90-100% at 3- and 6-months following ESWT treatment respectively. No major complications were seen in any of the studies. Minor complications included local soft tissue swelling, petechiae, bruising and pain.

CONCLUSIONS

The literature that is currently available is limited to case series of relatively small sample sizes, highlighting the need for a prospective randomised controlled trial to further investigate the efficacy of ESWT in the treatment of foot and ankle fracture non-unions.

The use of extracorporeal shock wave therapy for the treatment of bone marrow oedema - a systematic review and meta-analysis

BACKGROUND

Extracorporeal shock wave therapy (ESWT) has been used for various pathologies associated with bone marrow oedema (BME). However, it is still not clear whether ESWT may be favourable in the treatment of BME. Therefore, the aim of this systematic review was to assess the efficacy of ESWT for the treatment of BME.

METHODS

MEDLINE was searched for relevant literature with no time constraints. Both randomized and non-randomized trials were included. Case reports and conference abstracts were excluded. Titles and abstracts were screened and full-text articles of included studies were retrieved. Data on the effect of ESWT on pain, function, and the BME area on magnet resonance imaging were extracted.

RESULTS

Pain, function, and magnet resonance imaging results all improved across the studies - regardless of whether it was a randomized or non-randomized study. This effect was consistent across multiple pathologies such as osteonecrosis of the femoral head, BME associated with knee osteoarthritis, Kienböck's disease, and osteitis pubis. The meta-analysis showed that pain (after 1 month: weighted mean difference (WMD) = - 2.23, 95% CI - 2.58 to - 1.88, P < 0.0001; after 3-6 month: WMD = - 1.72, 95% CI - 2.52 to - 0.92, P < 0.00001) and function (after 1 month: WMD = - 1.59, 95% CI - 2.04 to - 1.14, P < 0.0001; after 3-6 month: WMD = - 2.06, 95% CI - 3.16 to - 0.96, P = 0.0002; after ≥ 12 month: WMD = - 1.20, 95% CI - 1.83 to - 0.56, P = 0.0002) was reduced in terms of ESWT treatment compared to a control group.

CONCLUSIONS

Based on the available evidence, ESWT may be an adequate option for conservative therapy in pathologies involving BME.

TRIAL REGISTRATION

PROSPERO, CRD42021201719 . Registered 23 December 2020.

Tips and tricks to achieve osteotomy healing and prevent refracture after ulnar shortening osteotomy

BACKGROUND

Parallel osteotomy is essential for favorable osteotomy reduction and healing and technically challenging during diaphyseal ulnar shortening osteotomy (USO). This study aimed to evaluate the advantages of guided osteotomy for parallel osteotomy and reduction osteotomies, healing over freehand osteotomy. It also aimed to identify surgical factors affecting healing after diaphyseal USO.

METHODS

Between June 2005 and March 2016, 136 wrists that had undergone diaphyseal USO for ulnar impaction syndrome (UIS) were evaluated. The wrists were divided into two groups according to the osteotomy technique (group 1: freehand osteotomy, 74 wrists; group 2: guided osteotomy, 62 wrists). The osteotomy reduction gap and time to osteotomy healing (union and consolidation) were compared between the groups. A multiple regression test was performed to identify the surgical factors affecting healing. The cut-off length of the reduction gap to achieve osteotomy union on time and the cut-off period to decide the failure of complete consolidation were statistically calculated.

RESULTS

The baseline characteristics did not differ between the two groups. The osteotomy reduction gap and time to osteotomy union, and complete consolidation were shorter in group 2 than in group 1 (p = 0.002, < 0.001, 0.002). The osteotomy reduction gap was a critical surgical factor affecting both time to osteotomy union and complete consolidation (p < 0.001, < 0.001). The use of a dynamic compression plate affected only the time to complete consolidation (p < 0.001). The cut-off length of the osteotomy reduction gap to achieve osteotomy union on time was 0.85 mm. The cut-off period to decide the failure of complete consolidation was 23.5 months after osteotomy.

CONCLUSIONS

The minimal osteotomy reduction gap was the most important for timely osteotomy healing in the healthy ulna, and guided osteotomy was beneficial for reducing the osteotomy reduction gap.

Emerging Options for Biologic Enhancement of Stress Fracture Healing in Athletes

In an era of continual single-sport specialization and year-round training, overuse injuries, including stress injuries of bone, are increasingly common. These injuries can be season- or even career-ending. For many elite and professional athletes, the traditional treatment strategy of immobilization and extended rest from sports participation is often not practical or acceptable. An understanding of modern strategies for evaluating and treating stress fractures is paramount for maintaining athletic participation and optimal athletic performance. This begins with the ability to categorize and stratify bony stress injuries by both severity and risk of fracture progression. Surgical procedures such as open reduction and internal fixation or intramedullary fixation with possible bone grafting remain the standard of care for chronic or severe stress fractures. However, emerging techniques to augment the biologic environment are a minimally invasive adjunct for stimulating and supporting bone healing in elite-level athletes to optimize bone health, expedite recovery, and decrease the risk of nonunion or catastrophic fracture.

Poly(lactic-co-glycolic acid)-bioactive glass composites as nanoporous scaffolds for bone tissue engineering: In vitro and in vivo studies

The aim of the present study was to investigate the feasibility of using composite scaffolds of poly(lactic-co-glycolic acid) (PLGA) and bioactive glass (BG) to repair bone defects. PLGA/BG composite scaffolds were prepared by thermally-induced phase separation. Scanning electron microscopy (SEM) was used to study the morphology, and liquid (absolute ethanol) replacement was used to calculate the porosity of the scaffold. The biocompatibility and degradation of the scaffold were determined using human osteosarcoma cell line MG-63 and animal experiments. SEM showed that the scaffold had a nanofibrous three-dimensional network structure with a fiber diameter of 160-320 nm, a pore size of 1-7 µm, and a porosity of 93.048±0.121%. The scaffold structure was conducive to cell adhesion and proliferation. It promoted cell osteogenesis and could be stably degraded in vivo.

Effect of Shockwave Treatment for Management of Upper and Lower Extremity Musculoskeletal Conditions: A Narrative Review

Extracorporeal shockwave therapy (ESWT) is a technology that was first introduced into clinical practice in 1982 for urologic conditions. Subsequent clinical applications in musculoskeletal conditions have been described in treatment of plantar fasciopathy, both upper and lower extremity tendinopathies, greater trochanteric pain syndrome, medial tibial stress syndrome, management of nonunion fractures, and joint disease including avascular necrosis. The aim of this review is to summarize the current understanding of treatment of musculoskeletal conditions with ESWT, accounting for differences in treatment protocol and energy levels. Complications from ESWT are rare but include 2 reported cases of injury to bone and Achilles tendon rupture in older adults using focused shockwave. Collectively, studies suggest ESWT is generally well-tolerated treatment strategy for multiple musculoskeletal conditions commonly seen in clinical practice. LEVEL OF EVIDENCE: III.

Extracorporeal Shock Wave Therapy in Acute Injury Care: A Systematic Review

Objectives:

We provide a systematic review of the literature to identify clinical studies assessing the effects of extracorporeal shock wave therapy (ESWT) on acutely injured tissues of human subjects, also highlighting the biological mechanisms by which the technique is proposed to promote the processes of early tissue repair. Special attention is also paid to the progress of research in animal models.

Method:

A systematic review of the literature on ESWT of acute injuries of bone and soft tissue as available in the PubMed/MEDLINE, Cochrane CENTRAL, SPORTDiscus, and CINAHL databases up to December 2017 was conducted.

Results:

A total of 10 studies were included. There is some evidence for the application of ESWT in an early postacute injury phase. Most studies report benefits with no or minimal side effects. However, different types of treated tissues and wounds (varying cause and severity) and resulting heterogeneity in study design and outcome measurement make it difficult to compare studies. The picture of knowledge remains limited by an apparent lack of data on optimal treatment timing and on tissue- and injury-specific parameters.

Conclusions:

Although the amount of studies to date is still limited, recent clinical research has presented first successful steps to introduce ESWT as a means of treatment in acute injury care. Therefore, on the basis of the analyzed data, further testing is encouraged to validate optimal timing, physical settings, and possible long-term effects to exclude potential risks.

High energy focused shock wave therapy accelerates bone healing

Objectives: To evaluate the influence of shock wave therapy (SWT) on radiographic evidence of bone healing after tibial plateau leveling osteotomy (TPLO).

Methods: Healthy dogs between two to nine years of age that underwent TPLO were randomly assigned to receive either electro- hydraulic SWT (1,000 shocks) or sham treatment (SHAM). Treatment or SHAM was administered to the osteotomy site immediately postoperatively and two weeks postoperatively. Three blinded radiologists evaluated orthogonal radiographs performed eight weeks postoperatively with both a 5-point and a 10-point bone healing scale. Linear regression analysis was used to compare median healing scores between groups.

Results: Forty-two dogs (50 stifles) were included in the statistical analysis. No major complications were observed and all osteo -tomies healed uneventfully. The median healing scores were significantly higher at eight weeks postoperatively for the SWT group compared to the SHAM group for the 10-point (p <0.0002) and 5-point scoring systems (p <0.0001).

Clinical significance: Shock wave therapy applied immediately and two weeks post -operatively led to more advanced bone healing at the eight week time point in this study population. The results of this study support the use of electro-hydraulic SWT as a means of accelerating acute bone healing of canine osteotomies. Additional studies are needed to evaluate its use for acceleration of bone healing following fracture, or with delayed union.

Effects of Roughly Focused Extracorporeal Shock Waves Therapy on the Expressions of Bone Morphogenetic Protein-2 and Osteoprotegerin in Osteoporotic Fracture in Rats

BACKGROUND

Roughly focused extracorporeal shock waves therapy (ESWT) is characterized by a wide focal area, a large therapy zone, easy positioning, and less pain during treatment. The purpose of this study was to investigate the effects of roughly focused ESWT on the expression of osteoprotegerin (OPG) and bone morphogenetic protein-2 (BMP-2) in osteoporotic fractures in rats.

METHODS

Seventy-two female Sprague-Dawley (SD) rats, 3 months old, were divided into sham-operated group (n = 6) and an ovariectomized (OVX) group (n = 66). Sixty OVX SD rats were used as a model of double proximal tibial osteotomy and inner fixation. The osteotomy site in the left tibia was treated with roughly focused ESWT once at an energy density of 0.26 mJ/mm2, 60 doses/min, and 2000 pact quantities. The contralateral right tibia was left untreated and served as a control. Expression of OPG and BMP-2 in the callus of the osteoporotic fracture area was assessed using immunohistochemistry, real-time polymerase chain reaction (PCR), and Western blotting analysis.

RESULTS

Bone mineral density (BMD) at the proximal tibia, femur, and L5 spine was significantly reduced after ovariectomy. BMD of proximal tibia was 12.9% less in the OVX group than that in the sham-operated group. Meanwhile, bilateral oophorectomy resulted in a lower trabecular bone volume fraction (BV/TV) in the proximal tibia of the sham-OVX animals. Three months after bilateral oophorectomy, BV/TV was 14.29% of baseline BV/TV in OVX legs versus 45.91% in the sham-OVX legs (P < 0.001). These data showed that the SD rats became a suitable model of osteoporosis, 3 months after they were OVX. Immunohistochemical analysis showed higher levels of BMP-2 and OPG expression in the treatment group than those in the control group. Compared with the contralateral controls, decreased expression of OPG and BMP-2 at 3 days after roughly focused ESWT, followed by a later increase at 7 days, was indicated by real-time PCR and Western blotting analysis. The OPG messenger RNA (mRNA) expression levels peaked at 6 weeks after the shock wave treatment, paired with a much earlier (at 4 weeks) increase of BMP-2, and declined close to normal at 8 weeks.

CONCLUSIONS

Roughly focused ESWT may promote the expression of OPG and BMP-2 in the osteoporotic fracture area in rats. BMP-2 and OPG may act synergistically and may lead to a significant enhancement of bone formation and remodeling.

Foot and Ankle Stress Fractures in Athletes

The incidence of stress fractures in the general athletic population is less than 1%, but may be as high as 15% in runners. Stress fractures of the foot and ankle account for almost half of bone stress injuries in athletes. These injuries occur because of repetitive submaximal stresses on the bone resulting in microfractures, which may coalesce to form complete fractures. Advanced imaging such as MRI and triple-phase bone scans is used to evaluate patients with suspected stress fracture. Low-risk stress fractures are typically treated with rest and protected weight bearing. High-stress fractures more often require surgical treatment.

Extracorporeal shockwave therapy (ESWT) ameliorates healing of tibial fracture non-union unresponsive to conventional therapy

Tibial non-unions are common cause of demanding revision surgeries and are associated with a significant impact on patients' quality of life and health care costs. Extracorporeal shockwave therapy (ESWT) has been shown to improve osseous healing in vitro and in vivo. The main objective of present study was to evaluate the efficacy of ESWT in healing of tibial non-unions unresponsive to previous surgical and non-surgical measures. A retrospective multivariant analysis of a prospective open, single-centre, clinical trial of tibia non-union was conducted. 56 patients with 58 eligible fractures who met the FDA criteria were included. All patients received 3000-4000 impulses of electrohydraulic shockwaves at an energy flux density of 0.4mJ/mm(2) (-6dB). On average patients underwent 1.9 times (±1.3SD) surgical interventions prior to ESWT displaying the rather negatively selected cohort and its limited therapy responsiveness. In 88.5% of patients receiving ESWT complete bone healing was observed after six months irrespective of underlying pathology. The multivariant analysis showed that time of application is important for therapy success. Patients achieving healing received ESWT earlier: mean number of days between last surgical intervention and ESWT (healed - 355.1 days±167.4SD vs. not healed - 836.7 days±383.0SD; p<0.0001). ESWT proved to be a safe, effective and non-invasive treatment modality in tibial non-unions recalcitrant to standard therapies. The procedure is well tolerated, time-saving, lacking side effects, with potential to significantly decrease health care costs. Thus, in our view, ESWT should be considered the treatment of first choice in established tibial non-unions.

Stress Fractures of the Foot

Stress fractures of the foot and ankle may be more common among athletes than previously reported. A low threshold for investigation is warranted and further imaging may be appropriate if initial radiographs remain inconclusive. Most of these fractures can be treated conservatively with a period of non-weight-bearing mobilization followed by gradual return to activity. Early surgery augmented by bone graft may allow athletes to return to sports earlier. Risk of delayed union, nonunion, and recurrent fracture is high. Many of the patients may also have risk factors for injury that should be modified for a successful outcome.

Effect of extracorporeal shockwave therapy (ESWT) on pulpal blood flow after orthodontic treatment: a randomized clinical trial

OBJECTIVES

The effect of non-invasive extracorporeal shockwaves on pulpal blood flow in orthodontic patients who have undergone active treatment was investigated.

MATERIALS AND METHODS

Seventy-two adult patients were enrolled in the clinical trial and allocated by block randomization to a treatment or a placebo group at a 1:1 ratio. The patients were required to be otherwise healthy. Blinding was performed for the subjects and the outcome assessor. The region of interest was the mandibular incisors and canines, which were vital, unrestored, and had experienced no trauma. The active treatment group received a single shockwave treatment with 1000 impulses at 0.19-0.23 mJ/mm(2) while the placebo group was treated with a deactivated shockwave applicator but acoustic sham. Pulpal blood flow was evaluated four times over a period of 6 months starting from the day of bracket removal, using a laser Doppler device.

RESULTS

Thirty patients were evaluated in each group. Orthodontic patients who have undergone active treatment tend to have high levels of pulpal blood flow which decrease over a period of 6 months. Pulpal blood flow did not differ significantly over 6 months between the placebo and treatment group. Shockwave treatment was associated with no significant effect in respect of tooth type, age, sex, or mean blood pressure, and had no unintended pernicious effects.

CONCLUSIONS

Extracorporeal shockwaves had no statistically significant effect on pulpal blood flow. Multiple applications of ESWT in a pathological setup may be needed in future studies to demonstrate significant differences.

CLINICAL RELEVANCE

The absence of any adverse effects justifies further principal investigations of the use of shockwave treatment in the oral cavity.

Soft-focused extracorporeal shock waves increase the expression of tendon-specific markers and the release of anti-inflammatory cytokines in an adherent culture model of primary human tendon cells

Focused extracorporeal shock waves have been found to upregulate the expression of collagen and to initiate cell proliferation in healthy tenocytes and to positively affect the metabolism of tendons, promoting the healing process. Recently, soft-focused extracorporeal shock waves have also been found to have a significant effect on tissue regeneration. However, very few in vitro reports have dealt with the application of this type of shock wave to cells, and in particular, no previous studies have investigated the response of tendon cells to this impulse. We devised an original model to investigate the in vitro effects of soft-focused shock waves on a heterogeneous population of human resident tendon cells in adherent monolayer culture. Our results indicate that soft-focused extracorporeal shock wave treatment (0.17 mJ/mm(2)) is able to induce positive modulation of cell viability, proliferation and tendon-specific marker expression, as well as release of anti-inflammatory cytokines. This could prefigure a new rationale for routine employment of soft-focused shock waves to treat the failed healing status that distinguishes tendinopathies.

Fifth metatarsal fractures in the athlete: evidence for management

Shortest time to union, and to return to sporting activity, are the goals of management of fifth metatarsal fractures in the athlete. Whereas zone 1 injuries are largely treated conservatively, zone 2 and 3 injuries are best treated with surgical fixation in athletes, most commonly with intramedullary screw fixation. Fixation with the addition of bone graft has also yielded good results. In the chronic setting, good results have been shown with intramedullary screw fixation, surgical debridement and bone grafting alone, and tension band wiring. Shock wave therapy and pulsed electromagnetic fields may have a place in chronic and acute injury.

Stress fracture

Stress fractures are common overuse type injuries, caused by repetitive stresses applied to bone leading to a change within the normal physiological balance and altering key structural properties. These injuries have been well documented within certain groups of the population, as well as related to certain activity types, and pose significant diagnostic and treatment challenges. Complication of stress fractures can vary dependant of the anatomical site and the prognosis of an injury can have wide ranging effects, dependant of lifestyle choices and occupation of the patient. This piece endeavours to outline the most current and evidentiary concepts pertaining to important aspects of stress fractures, from pathophysiology through to prognosis.