Role of Ultrasound Therapy in the Healing of Tibial Stress Fractures

Evaluation of Low-Intensity Pulsed Ultrasound on Stress Fractures to Reduce the Time to Return to Sport or Activity in the Physically Active Population: A Systematic Review

Stress fractures are a common and significant source of pain and burden that can require long periods of rest from physical activity to allow adequate healing. Specifically in athletes or those with physically demanding occupations, the prolonged period of rest and the potential for requiring surgical intervention in the case of poor or delayed healing can have devastating impacts on these individuals' careers and socioeconomic well-being. In this population, successful healing, in addition to a quicker healing time and a sooner return to activity, are important outcomes when faced with treating stress fractures. The use of low-intensity pulsed ultrasound (LIPUS) to accelerate bone healing has been a topic of investigation, though little research has explored the use of LIPUS specifically in the physically active population. The purpose of this study was to review the existing literature on the use of LIPUS for stress fracture healing in the physically active population with the outcome of a quicker return to sport or physical duties. The PubMed and Embase databases were screened for relevant articles using defined Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. Two independent researchers screened articles using PICOS criteria for inclusion in the review. Data were independently extracted regarding study and population characteristics as well as outcome measures, including time to healing of fractures and time to return to sport or physical activity. Five studies were ultimately included in the systematic review. One study investigated the use of LIPUS in pediatric athletes with spondylolysis, while four studies investigated lower extremity stress fractures in adult populations. All reported the outcomes of either rate or time to healing and ability to return to sport or activity. One study found a statistically significant improvement in the rate of bone union in the intervention group undergoing LIPUS compared to the control. Two studies found a statistically significant decrease in the time to resolution of symptoms, allowing an earlier return to sport or physical duties. Two studies found no difference in the time to healing or success rate of healing between the LIPUS group and the control group. This review of the literature suggests that the use of LIPUS for the treatment of stress fractures in the athletic or physically active population has the potential to expedite the resolution of symptoms and return to activity. Due to the heterogeneity of the existing studies, more research is needed to definitively determine the most appropriate clinical application of LIPUS and its most effective ultrasound settings. Further research should be directed toward more controlled studies specifically investigating the athletic and physically active population.

Nonoperative Management of Tibial Stress Fractures Result in Higher Return to Sport Rates Despite Increased Failure Versus Operative Management: A Systematic Review

Purpose

To compare return to sport (RTS) rates and complications after nonoperative versus operative management of tibial stress fractures.

Methods

A literature search was conducted per the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines using EMBASE, PubMed, and Scopus computerized data from database inception to February 2023. Studies evaluating RTS sport rates and complications after nonoperative or operative management of tibial stress fractures were included. Failure was defined as defined by persistent stress fracture line seen on radiographic imaging. Study quality was assessed using the Modified Coleman Methodology Score.

Results

Twenty-two studies consisting of 341 patients were identified. The overall RTS rate ranged from 91.2% to 100% in the nonoperative group and 75.5% to 100% in the operative group. Failures rates ranged from 0% to 25% in the nonoperative groups and 0% to 6% in the operative group. Reoperations were reported in 0% to 6.1% of patients in the operative group, whereas 0% to 12.5% of patients initially managed nonoperatively eventually required operative treatment.

Conclusions

Patients can expect high RTS rates after appropriate nonoperative and operative management of tibial stress fractures. Treatment failure rates were greater in patients undergoing nonoperative management, with up to 12.5% initially treated nonoperatively later undergoing operative treatment.

Level of Evidence

Level IV; Systematic Review of level I-IV studies.

Ultrasound and shockwave therapy for acute fractures in adults

BACKGROUND

The morbidity and socioeconomic costs of fractures are considerable. The length of time to healing is an important factor in determining a person's recovery after a fracture. Ultrasound may have a therapeutic role in reducing the time to union after fracture by stimulating osteoblasts and other bone-forming proteins. This is an update of a review previously published in February 2014.   OBJECTIVES: To assess the effects of low-intensity ultrasound (LIPUS), high-intensity focused ultrasound (HIFUS) and extracorporeal shockwave therapies (ECSW) as part of the treatment of acute fractures in adults.  SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase (1980 to March 2022), Orthopaedic Proceedings, trial registers and reference lists of articles.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-RCTs including participants over 18 years of age with acute fractures (complete or stress fractures) treated with either LIPUS, HIFUS or ECSW versus a control or placebo-control.

DATA COLLECTION AND ANALYSIS

We used standard methodology expected by Cochrane. We collected data for the following critical outcomes: participant-reported quality of life, quantitative functional improvement, time to return to normal activities, time to fracture union, pain, delayed or non-union of fracture. We also collected data for treatment-related adverse events. We collected data in the short term (up to three months after surgery) and in the medium term (later than three months after surgery).   MAIN RESULTS: We included 21 studies, involving 1543 fractures in 1517 participants; two studies were quasi-RCTs. Twenty studies tested LIPUS and one trial tested ECSW; no studies tested HIFUS. Four studies did not report any of the critical outcomes. All studies had unclear or high risk of bias in at least one domain. The certainty of the evidence was downgraded for imprecision, risk of bias and inconsistency. LIPUS versus control (20 studies, 1459 participants) We found very low-certainty evidence for the effect of LIPUS on Health-related quality of life (HRQoL) measured by SF-36 at up to one year after surgery for lower limb fractures (mean difference (MD) 0.06, 95% confidence interval (CI) -3.85 to 3.97, favours LIPUS; 3 studies, 393 participants). This result was compatible with a clinically important difference of 3 units with both LIPUS or control. There may be little to no difference in time to return to work after people had complete fractures of the upper or lower limbs (MD 1.96 days, 95% CI -2.13 to 6.04, favours control; 2 studies, 370 participants; low-certainty evidence).  There is probably little or no difference in delayed union or non-union up to 12 months after surgery (RR 1.25, 95% CI 0.50 to 3.09, favours control; 7 studies, 746 participants; moderate-certainty evidence). Although data for delayed and non-union included both upper and lower limbs, we noted that there were no incidences of delayed or non-union in upper limb fractures. We did not pool data for time to fracture union (11 studies, 887 participants; very low-certainty evidence) because of substantial statistical heterogeneity which we could not explain. In upper limb fractures, MDs ranged from 0.32 to 40 fewer days to fracture union with LIPUS. In lower limb fractures, MDs ranged from 88 fewer days to 30 more days to fracture union. We also did not pool data for pain experienced at one month after surgery in people with upper limb fractures (2 studies, 148 participants; very low-certainty evidence) because of substantial unexplained statistical heterogeneity. Using a 10-point visual analogue scale, one study reported less pain with LIPUS (MD -1.7, 95% CI -3.03 to -0.37; 47 participants), and the effect was less precise in the other study (MD -0.4, 95% CI -0.61 to 0.53; 101 participants). We found little or no difference in skin irritation (a possible treatment-related adverse event) between groups but judged the certainty of the evidence from this small study to be very low (RR 0.94, 95% CI 0.06 to 14.65; 1 study, 101 participants). No studies reported data for functional recovery. Data for treatment adherence were inconsistently reported across studies, but was generally described to be good. Data for costs were reported for one study, with higher direct costs, as well as combined direct and indirect costs, for LIPUS use. ECSW versus control (1 study, 56 participants) We are uncertain whether ECSW reduces pain at 12 months after surgery in fractures of the lower limb (MD -0.62, 95% CI -0.97 to -0.27, favours ECSW); the difference between pain scores was unlikely to be clinically important, and the certainty of the evidence was very low. We are also uncertain of the effect of ECSW on delayed or non-union at 12 months because the certainty of this evidence is very low (RR 0.56, 95% CI 0.15 to 2.01; 1 study, 57 participants). There were no treatment-related adverse events. This study reported no data for HRQoL, functional recovery, time to return to normal activities, or time to fracture union. In addition, no data were available for adherence or cost.

AUTHORS' CONCLUSIONS

We were uncertain of the effectiveness of ultrasound and shock wave therapy for acute fractures in terms of patient-reported outcome measures (PROMS), for which few studies reported data. It is probable that LIPUS makes little or no difference to delayed union or non-union. Future trials should be double-blind, randomised, placebo-controlled trials recording validated PROMs and following up all trial participants. Whilst time to union is difficult to measure, the proportion of participants achieving clinical and radiographic union at each follow-up point should be ascertained, alongside adherence with the study protocol and cost of treatment in order to better inform clinical practice.

Low-Intensity Pulsed Ultrasound for Early-Stage Lumbar Spondylolysis in Young Athletes

OBJECTIVE

To examine the effect of low-intensity pulsed ultrasound (LIPUS) on early-stage spondylolysis in young athletes.

DESIGN

Case-control study.

SETTING

A single outpatient orthopedic and sports clinic.

PATIENTS

A total of 82 young athletes (80 boys and 2 girls; mean age, 14.8 years; range, 10-18 years) with early-stage lumbar spondylolysis were enrolled in this study. All patients were examined by plain radiography and magnetic resonance imaging.

INTERVENTIONS

Patients received either standard conservative treatment combined with LIPUS (n = 35) or without LIPUS (n = 47), according to the sequence of admission. The standard conservative treatment included thoracolumbosacral brace, sports modification, and therapeutic exercise.

MAIN OUTCOME MEASURES

The time required to return to previous sports activities was analyzed by using Kaplan-Meier methods with the log-rank test.

RESULTS

The baseline parameters of both groups were not significantly different. The median time to return to previous sports activities was 61 days [95% confidence interval (CI): 58-69 days] in the group treated with LIPUS, which was significantly shorter than that of the group treated without LIPUS (167 days, 95% CI: 135-263 days; P < 0.01).

CONCLUSIONS

These results suggest that LIPUS combined with conservative treatment for early-stage lumbar spondylolysis in young athletes could be a useful therapy for quick return to playing sports.

Enhancement of Bone-Healing by Low-Intensity Pulsed Ultrasound: A Systematic Review

BACKGROUND

Low-intensity pulsed ultrasound (LIPUS) is frequently used to enhance or to accelerate fracture-healing, but its clinical role and effectiveness as a treatment modality remain uncertain. We performed a systematic review and meta-analysis of randomized controlled trials to determine the efficiency of LIPUS on bone-healing and/or fracture union, as well as on functional recovery.

METHODS

The databases of PubMed/MEDLINE, Cochrane Central Register of Controlled Trials, CINAHL, Web of Science, and Embase were searched for trials concerning LIPUS stimulation and bone-healing or fracture repair, in any language, published from the inception of the database to January 2, 2015. Eligible studies were randomized controlled trials that enrolled patients with any type of fracture, delayed union, or nonunion and randomly assigned them to LIPUS treatment or a control group. Two reviewers independently agreed on eligibility, assessed methodological quality, and extracted outcome data. All relevant outcomes were pooled, and a meta-analysis was performed.

RESULTS

Twenty-four unique randomized trials were selected for analysis after the search of all databases and the inclusion of one trial by the senior author. Time to radiographic fracture union was the most common primary outcome measure evaluated. After pooling the data concerning time to radiographic healing in the combined patient population (n = 429), LIPUS treatment resulted in a mean reduction in healing time of 39.8 days (95% confidence interval, 17.7 to 62.0 days; I = 94%). The most reduction in time to radiographic union by LIPUS treatment was seen in fractures with a long natural healing tendency. Three trials evaluating the time to return to work or active duty, as a surrogate for functional recovery, were unable to demonstrate a beneficial effect of LIPUS (n = 179). Evidence from two high-quality trials implied that LIPUS enhances fracture-healing through increased bone formation in cases of delayed and/or impaired bone-healing. The prevention of delayed union or nonunion by LIPUS treatment could not be demonstrated.

CONCLUSIONS

LIPUS treatment effectively reduces the time to radiographic fracture union, but this does not directly result in a beneficial effect of accelerated functional recovery or the prevention of delayed union or nonunion. The increase in bone formation as a result of LIPUS treatment may provide a valuable tool in fracture repair, but it does not always lead to healing. Future studies should focus on reporting of a combination of subjective signs of clinical healing, functional recovery, and radiographic union to determine the effectiveness of LIPUS treatment in clinical fracture-healing.

LEVEL OF EVIDENCE

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

Comparison of effects of LLLT and LIPUS on fracture healing in animal models and patients: A systematic review

The aim of this paper is to study the in vivo potency of low-level laser therapy (LLLT) and low intensity pulsed ultrasound (LIPUS) alone, accompanied by bone grafts, or accompanied by other factors on fracture healing in animal models and patients. In this paper, we aim to systematically review the published scientific literature regarding the use of LLLT and LIPUS to accelerate fracture healing in animal models and patients. We searched the PubMed database for the terms LLLT or LIPUS and/or bone, and fracture. Our analysis also suggests that both LIPUS and LLLT may be beneficial to fracture healing in patients, and that LIPUS is more effective. These finding are of considerable importance in those treatments with a LIPUS, as a laser device may reduce healing time. The most clinically relevant impact of the LIPUS treatment could be a significant reduction in the proportion of patients who go on to develop a nonunion. If it is confirmed that the therapeutic influence is true and reliable, patients will obtain benefits from LIPUS and LLLT. Further clinical trials of high methodological quality are needed in order to determine the optimal role of LIPUS and LLLT in fracture healing in patients.

The effects of low-intensity pulsed ultrasound on fresh fracture: A meta-analysis

BACKGROUND

Low-intensity pulsed ultrasonography (LIPUS) is a form of mechanical stimulation that is delivered via a special device to the fracture site for the acceleration of fracture healing. We conducted a meta-analysis to assess the effect of LIPUS for fresh fractures in adults.

METHODS

MEDLINE, EMBASE and the Cochrane Library searched between Jan 1980 and Nov 2016. Studies should be quasi-randomized and randomized controlled trials (RCTs) comparing treatment with LIPUS to placebo or no treatment in adults with fresh fractures, reporting outcomes such as function; time to union; delayed union or non-union. Summary standard mean difference (SMD) and the risk ratio (RR) with their 95% confidence interval (CI) calculated with a random effects model. I statistic was used to assess the heterogeneity. Risk of bias was assessed by the Cochrane risk-of-bias tool. The GRADE system was used to evaluate the evidence quality.

RESULTS

A total of 12 trials with 1099 patients were included. The pooled results showed that LIPUS significantly reduced the time to fracture union (SMD: 0.65, 95% CI: 1.13 to 0.17), improved the quality of life (SMD: 0.20, 95% CI: 0.03-0.37) without affecting the time to full weight bearing (SMD: 0.76, 95% CI: 1.92 to 0.4), the time to return to work (SMD: 0.06, 95% CI: 0.14 to 0.27), or the incidence rate of delayed union and nonunion (RR: 1.02, 95% CI: 0.60-1.74).

CONCLUSIONS

Moderate-to-high quality evidence shows that LIPUS treatment reduces the time to fracture union and improves the quality of life without affecting functional recovery and incident rate of delayed union and nonunion, suggesting that LIPUS treatment may be a good treatment modality for adults with fresh fractures. However, there are some methodological limitations in the eligible trials, further studies are needed to determine the clinical circumstances under which LIPUS is truly valid and to examine the optimal approach for the use of this adjunctive therapy.

Low-intensity pulsed ultrasound in lower limb bone stress injuries: a randomized controlled trial

OBJECTIVE

To evaluate the effectiveness of low-intensity pulsed ultrasound (LIPUS) for the improvement of lower limb bone stress injuries in a civilian population.

DESIGN

A prospective, randomized, double-blinded, placebo-controlled trial to compare LIPUS with placebo.

SETTING

Civilian private practice population in Sydney, Australia.

PARTICIPANTS

Subjects were recruited if a grade II-IV bone stress injury was diagnosed on magnetic resonance imaging (MRI) of either the postero-medial tibia, fibula or second, third, or fourth metatarsal. Subjects of all levels of sporting activity were included. Thirty subjects were initially recruited, and 23 subjects were included in the final analysis.

INTERVENTIONS

Subjects were randomized into either the treatment or placebo arm and matched to the site of injury (tibia, fibula, or metatarsal). Subjects in both arms used either treatment or placebo devices for 20 minutes daily for 4 weeks.

MAIN OUTCOME MEASURES

Six clinical parameters (night pain, pain at rest, pain on walking, pain with running, tenderness, and pain with single leg hop) were compared before and after intervention. The changes in MRI grade and bone marrow edema size were also compared.

RESULTS

There were no significant differences between the treatment and placebo conditions for changes in MRI grading (2.2 vs 2.4, P = 0.776) or bone marrow edema size (3 vs 4.1, P = 0.271). There were no significant differences between the treatment and placebo conditions for the 6 clinical parameters.

CONCLUSIONS

Low-intensity pulsed ultrasound was found not to be an effective treatment for the healing of lower limb bone stress injuries in this study. However, this was measured over a relatively short duration of 4 weeks in a small, mostly female population.

CLINICAL RELEVANCE

This double-blinded, randomized, placebo-controlled trial has shown that LIPUS is not an effective treatment for lower limb bone stress injuries.

Ultrasound and shockwave therapy for acute fractures in adults

BACKGROUND

The morbidity and socioeconomic costs of fractures are considerable. The length of time to healing is an important factor in determining a person's recovery after a fracture. Ultrasound may have a therapeutic role in reducing the time to union after fracture. This is an update of a review previously published in February 2012.

OBJECTIVES

To assess the effects of low-intensity ultrasound (LIPUS), high-intensity focused ultrasound (HIFUS) and extracorporeal shockwave therapies (ECSW) as part of the treatment of acute fractures in adults.

SEARCH METHODS

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (2 June 2014), the Cochrane Central Register of Controlled Trials (The Cochrane Library 2014, Issue 5), MEDLINE (1946 to May Week 3 2014), EMBASE (1980 to 2014 Week 22), trial registers and reference lists of articles.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials evaluating ultrasound treatment in the management of acute fractures in adults. Studies had to include participants over 18 years of age with acute fractures, reporting outcomes such as function; time to union; non-union; secondary procedures such as for fixation or delayed union or non-union; adverse effects; pain; costs; and patient adherence.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data from the included studies. Treatment effects were assessed using mean differences, standardised mean differences or risk ratios using a fixed-effect model, except where there was substantial heterogeneity, when data were pooled using a random-effects model. Results from 'worst case' analyses, which gave more conservative estimates of treatment effects for time to fracture union, are reported in preference to those from 'as reported' analyses.

MAIN RESULTS

We included 12 studies, involving 622 participants with 648 fractures. Eight studies were randomised placebo-controlled trials, two were randomised controlled trials without placebo controls, one was a quasi-randomised placebo-controlled trial and one was a quasi-randomised controlled trial without placebo control. Eleven trials tested LIPUS and one trial tested ECSW. Four trials included participants with conservatively treated upper limb complete fractures and six trials included participants with lower limb complete fractures; these were surgically fixed in four trials. The remaining two trials reported results for conservatively treated tibial stress fractures.'Risk of bias' assessment of the included studies was hampered by the poor reporting of methods, frequently resulting in the risk of bias of individual domains being judged as 'unclear'. Both quasi-randomised studies were at high risk of bias, including selection and attrition bias. Three studies were at low risk of selection bias relating to allocation concealment the majority of studies were at low risk of performance bias as they employed a form of intervention blinding.Only limited data were available from three of only four studies reporting on functional outcome. One study of complete fractures found little evidence of a difference between the two groups in the time to return to work (mean difference (MD) 1.95 days favouring control, 95% confidence interval (CI) -2.18 to 6.08; 101 participants). Pooled data from two studies found LIPUS did not significantly affect the time to return to training or duty in soldiers or midshipmen with stress fractures (MD -8.55 days, 95% CI -22.71 to 5.61; 93 participants).We adopted a conservative strategy for data analysis that was more likely to underestimate than to overestimate a benefit of the intervention. After pooling results from eight studies (446 fractures), the data showed no statistically significant reduction in time to union of complete fractures treated with LIPUS (standardised mean difference (SMD) -0.47, 95% CI -1.14 to 0.20). This result could include a clinically important benefit or harm, and should be seen in the context of the highly significant statistical heterogeneity (I² = 90%). This heterogeneity was not explained by the a priori subgroup analyses (upper limb versus lower limb fracture, smoking status). An additional subgroup analysis comparing conservatively and operatively treated fractures raised the possibility that LIPUS may be effective in reducing healing time in conservatively managed fractures, but the test for subgroup differences did not confirm a significant difference between the subgroups.Pooled results from five of the eight trials (333 fractures) reporting proportion of delayed union or non-union showed no significant difference between LIPUS and control (10/168 versus 13/165; RR 0.75; 95% CI 0.24 to 2.28). Adverse effects directly associated with LIPUS and associated devices were found to be few and minor, and compliance with treatment was generally good. One study reporting on pain scores found no difference between groups at eight weeks (101 participants).One quasi-randomised study found no significant difference in non-union at 12 months between internal fixation supplemented with ECSW and internal fixation alone (3/27 versus 6/30; RR 0.56, 95% CI 0.15 to 2.01). There was a clinically small but statistically significant difference in the visual analogue scores for pain in favour of ECSW at three month follow-up (MD -0.80, 95% CI -1.23 to -0.37). The only reported complication was infection, with no significant difference between the two groups.

AUTHORS' CONCLUSIONS

While a potential benefit of ultrasound for the treatment of acute fractures in adults cannot be ruled out, the currently available evidence from a set of clinically heterogeneous trials is insufficient to support the routine use of this intervention in clinical practice. Future trials should record functional outcomes and follow-up all trial participants.

Low-intensity pulsed ultrasonography versus electrical stimulation for fracture healing: a systematic review and network meta-analysis

BACKGROUND

To best inform evidence-based patient care, it is often desirable to compare competing therapies. We performed a network meta-analysis to indirectly compare low intensity pulsed ultrasonography (LIPUS) with electrical stimulation (ESTIM) for fracture healing.

METHODS

We searched the reference lists of recent reviews evaluating LIPUS and ESTIM that included studies published up to 2011 from 4 electronic databases. We updated the searches of all electronic databases up to April 2012. Eligible trials were those that included patients with a fresh fracture or an existing delayed union or nonunion who were randomized to LIPUS or ESTIM as well as a control group. Two pairs of reviewers, independently and in duplicate, screened titles and abstracts, reviewed the full text of potentially eligible articles, extracted data and assessed study quality. We used standard and network meta-analytic techniques to synthesize the data.

RESULTS

Of the 27 eligible trials, 15 provided data for our analyses. In patients with a fresh fracture, there was a suggested benefit of LIPUS at 6 months (risk ratio [RR] 1.17, 95% confidence interval [CI] 0.97-1.41). In patients with an existing nonunion or delayed union, ESTIM had a suggested benefit over standard care on union rates at 3 months (RR 2.05, 95% CI 0.99-4.24). We found very low-quality evidence suggesting a potential benefit of LIPUS versus ESTIM in improving union rates at 6 months (RR 0.76, 95% CI 0.58-1.01) in fresh fracture populations.

CONCLUSION

To support our findings direct comparative trials with safeguards against bias assessing outcomes important to patients, such as functional recovery, are required.

Stress fractures-a prospective study amongst recruits

BACKGROUND

Stress fracture (SF) is the single most common cause for the lost number of manpower days during training of recruits in the Armed Forces. This prospective study was undertaken with a view to develop baseline data on incidence of SF and to identify related variables.

METHODS

A prospective study over a period of five years during 2004-2009 in which a total of 8,570 recruits were enrolled at the start of their training to find out the incidence and pattern of SFs.

RESULTS

A total of 604 (7.04%, 95% CI 6.40-7.40%) out of a total of 8,570 recruits sustained SF during the study period. The majority of fractures occurred during basic training. The factors like urban residence, vegetarianism and those without prior history of physical activity were found to be associated with SF. Tibia was the commonest bone involved.

CONCLUSION

Prevention is undoubtedly the best approach in SF and other sports injuries. Priority should be given to individuals with good sports and physical activity background during recruitment. Intensity of training should be gradually increased during first three months (12 weeks) of training.

Ultrasound and shockwave therapy for acute fractures in adults

BACKGROUND

The morbidity and socioeconomic costs of fractures are considerable. The length of time to healing is an important factor in determining a patient's recovery after a fracture. Ultrasound may have a therapeutic role in reducing the time to union after fracture.

OBJECTIVES

To assess the effects of low intensity ultrasound (LIPUS), high intensity focused ultrasound (HIFUS) and extracorporeal shockwave therapies (ECSW) as part of the treatment of acute fractures in adults.

SEARCH METHODS

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (December 2011), the Cochrane Central Register of Controlled Trials (in The Cochrane Library 2011, Issue 4), MEDLINE (1950 to November Week 3 2011), EMBASE (1980 to 2011 Week 49), trial registers and reference lists of articles.

SELECTION CRITERIA

Randomised controlled trials evaluating ultrasound treatment in the management of acute fractures in adults. Studies including participants over 18 years of age with acute fractures, reporting functional outcomes, time to union, non-union, secondary procedures such as for fixation or delayed or non-union, adverse effects, pain, costs or patient adherence were included.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data from the included studies. Treatment effects were assessed using mean differences or risk ratios and, where there was substantial heterogeneity, pooled using a random-effects model. Results from 'worst case' analyses, which gave more conservative estimates of treatment effects for time to fracture union, are reported in preference to those from 'as reported' analyses.

MAIN RESULTS

Twelve studies, involving 622 participants with 648 fractures, were included. Eight studies were randomised placebo-controlled trials, two studies were randomised controlled trials without placebo controls, one study was a quasi-randomised placebo controlled trial and the remaining study was a quasi-randomised controlled trial without placebo control. Eleven trials tested LIPUS and one trial tested ECSW. Four trials included participants with conservatively treated upper limb complete fractures and six trials included participants with lower limb complete fractures; these were surgically fixed in four trials. The remaining two trials reported results for conservatively treated tibial stress fractures.Very limited data from two complete fracture studies showed no difference between ultrasound and placebo control in functional outcome. Pooled estimates from two studies found LIPUS did not significantly affect the time to return to training or duty in soldiers or midshipmen with stress fractures (mean difference -8.55 days, 95% CI -22.71 to 5.61).Based on a 'worst case' analysis, which adjusted for incomplete data, pooled results from eight heterogeneous studies showed no statistically significant reduction in time to union of complete fractures treated with LIPUS (standardised mean difference -0.47, 95% CI -1.14 to 0.20). This result could include a clinically important benefit or harm, and should be seen in the context of the highly significant statistical heterogeneity (I² = 90%). This heterogeneity was not explained by the a priori subgroup analyses (upper limb versus lower limb fracture, smoking status). An additional subgroup analysis comparing conservatively and operatively treated fractures raised the possibility that LIPUS may be effective in reducing healing time in conservatively managed fractures, but the test for subgroup differences did not confirm a significant difference between the subgroups.Pooled results from eight trials reporting proportion of delayed union or non-union showed no significant difference between LIPUS and control. Adverse effects directly associated with LIPUS and associated devices were found to be few and minor, and compliance with treatment was generally good. One study reporting on pain scores found no difference between groups at eight weeks.One quasi-randomised study (59 fractures) found no significant difference between ECSW and no-placebo control groups in non-union at 12 months (risk ratio 0.56, 95% CI 0.15 to 2.01). There was a clinically small but statistically significant difference in the visual analogue scores for pain in favour of ECSW at three month follow-up. The only reported complication was infection, with no significant difference between the two groups.

AUTHORS' CONCLUSIONS

While a potential benefit of ultrasound for the treatment of acute fractures in adults cannot be ruled out, the currently available evidence from a set of clinically heterogeneous trials is insufficient to support the routine use of this intervention in clinical practice. Future trials should record functional outcomes and follow-up all trial participants.

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.