Fractures defined by a loss of continuity of the bony surface caused by a direct or indirect force constitute a heavy burden in terms of morbidity and costs. Between 5% and 10% of long-bone fractures tend to not heal or to heal after the expected time. This prolongs morbidity and increases costs even further, reducing independence and productivity. Different interventions have been proposed to accelerate bone healing, among which are ultrasound and shockwave therapy. Ultrasound applies low-energy, high-frequency sound waves through a device on the fracture site, whereas shockwave therapy applies a high-energy sound wave for the same time duration. This therapy may help in healing the fracture by mechanically stimulating the site of injury, thus simulating functional loading by inducing low-level mechanical forces at the fracture site, even if the effects have not yet been fully elucidated and its use remains controversial. This review updates the summary of the available best evidence on the use of these types of physical or instrumental therapy for acute fractures and their effects.
This review is important for:
People who have fractures that do not tend to heal and who experience long periods of morbidity and inactivity, their loved ones/caregivers, health professionals caring for this population, general practitioners, researchers, and policymakers.
Outcomes of this review
This is an update of a Cochrane Systematic Review (CSR) published in 2014. The outcomes analyzed were patient-reported outcome measures (PROMs) such as quality of life (QoL), time to return to normal activities such as work, time to fracture union, pain, delayed or non-union, adverse events, costs, and adherence. The CSR included 19 randomized controlled trials (RCTs), plus two studies that were quasi-RCTs, published and/or registered up to March 2022, involving 1,543 fractures in 1,517 participants. Results showed that it is uncertain whether low-intensity pulsed ultrasound (LIPUS) or extracorporeal shockwave therapy (ECSW), compared to sham or no sham control, improves the quality of life after a fracture. Ultrasound probably makes little to no difference in delayed union or non-union at 12 months, whereas the difference is uncertain for ECSW. LIPUS probably makes little to no difference in time to return to work in complete limb fractures and in adverse events such as skin irritation. No studies reported data for functional recovery, and adherence was inconsistently reported. One study outlined higher costs for LIPUS use. On the other hand, ECSW therapy may very slightly reduce pain one month after injury in people who have a broken bone in their thigh or shin bone. However, it is unlikely that this reduction in pain will be meaningful. There were no treatment-related adverse events. No data were available for health-related quality of life, functional recovery, time to return to activities, time to fracture union, adherence, or cost.
These results must be interpreted with caution because (i) no studies assessed high-intensity focused ultrasound. (ii) Almost no studies reported on quality-of-life measurements. (iii) The studies that reported pain-outcome scores were too heterogeneous to be analyzed. (iv) There were very little data for ECSW with very low- certainty evidence for pain outcome. (v) Pooling was not possible for time to fracture union due to unexplainable heterogeneity. (vi) The definition of fracture healing is heterogenous, making the outcome difficult to assess. (vii) The settings were typically hospitals; therefore, evidence is limited in other contexts. (viii) Adherence was inconsistently reported. (ix) The small study size led to imprecision and wide confidence intervals (CIs). (x) Some studies were at high risk of performance and detection bias, and others of attrition, inconsistency, and publication bias. (xii) Post-hoc subgroup analysis options were not explored to attempt to explain the heterogeneity.
Author’s conclusion of the review
For people who have an acute fracture, there is currently insufficient evidence on the effectiveness of low-intensity pulsed ultrasound (LIPUS) on quality of life; it probably makes no difference in delayed or non-union. Similarly, evidence for extracorporeal shockwave therapy (ECSW) was limited to one study but showed some reduction in pain, although the reduction is likely not clinically significant. No studies investigated high-intensity focused ultrasound.
Future recommendations
The authors recommend for future trials a double-blind, randomized, placebo-controlled design with appropriate randomization protocol, and control placebo groups that use “sham” intervention. The study population should be those with fractures at risk of delayed union or non-union. These studies should be subjected to CONSORT standards for prospective registration. They should aim to improve follow-up and try to decrease dropouts. Compliance should be measured and reported, and g) reporting should also focus on PROMs to measure the tangible effect of the intervention on patients’ lives.
summary by Robin Kuruvila Sentinella