SLR - September 2017 - Jeffrey E. Stych

Heal Rate of Metatarsal Fractures: A Propensity-Matching Study of Patients Treated with Low-Intensity Pulsed Ultrasound (LIPUS) vs. Surgical and Other Treatments

Reference: Nolte P, Anderson R, Strauss E, Wang Z, Hu L, Xu Z, Grant Steen R. Heal Rate of Metatarsal Fractures: A Propensity-matching Study of Patients Treated with Low-intensity Pulsed Ultrasound (LIPUS) vs. Surgical and Other Treatments. Injury. 2016 Nov; 47(11):2584–2590

Scientific Literature Review

Reviewed By: Jeffrey E. Stych, DPM
Residency Program: Beaumont Hospital, Farmington Hills, MI

Podiatric Relevance: There is still debate about the ideal way to treat metatarsal fractures (i.e., surgically vs. conservatively). Oftentimes, reaching a conclusion on how to effectively treat metatarsal fractures is not straightforward. Many factors can play a role in the decision-making process. These factors include, but are not limited to, patient age, sex, bone density, smoking status, other medical conditions, location of the fracture and fracture characteristics. While surgical intervention may reduce the incidence of nonunion, conservative management eliminates some of the other complications inherent to surgery (e.g., infection, wound dehiscence, etc).

Methods: This is a retrospective observational cohort study of consecutive consenting patients with a metatarsal fracture who had enrolled prospectively in a low-intensity pulsed ultrasound (LIPUS) study. Inclusion criteria were males and nonpregnant females 18 years or older at the time of enrollment and had signed informed consent. Patients were instructed to use the LIPUS device for 20 minutes daily until healed. The prescribing physician determined a dichotomous variable of healed/failed at treatment end. Healing was defined both clinically and radiographically. A fracture was defined as healed when there was no motion or tenderness with palpation, and at least three of four cortices were bridged on radiographs. The LIPUS group was compared with a nationwide data registry (non-LIPUS treatment), coded for metatarsal fracture from 2011. Comparisons were made between the groups for fractures treated within one year and then separately for fresh fractures and delayed/nonunion fractures.

Results: 98.4 percent of LIPUS-treated, simple, nondisplaced fractures healed. Overall, 94.9 percent of all LIPUS-treated fractures healed. These results were comparable to patients treated in 2011 by various methods. However, after a propensity match between the two groups, LIPUS was superior. LIPUS was also superior for fresh fractures, and comparable for delayed/nonunion fractures, compared to the 2011 group.

Conclusions: LIPUS alone is effective for treating metatarsal fractures and equivalent to surgical intervention without the complications inherent to surgery. LIPUS (prior to propensity match) was also shown to be equal to the surgically treated group for metatarsal fractures even though the LIPUS group patients were more likely to be obese, smoke and have an open fracture. Lastly, LIPUS significantly improved the heal rate of metatarsal fractures <1 year old without surgery. Based on the findings of this study, LIPUS is yet another option for management of metatarsal fractures when surgical intervention is not an option, can be considered in addition to other modalities if the patient has risk factors for developing delayed and nonunions and is an effective modality for treating delayed unions and nonunions should they develop. Further research could look into comparing LIPUS, electrical stimulation bone stimulators and extracorporeal shockwave therapy for metatarsal fractures.

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