Photobiomodulation therapy versus sham for tibial and metatarsal bone stress injuries in military trainees: A randomized controlled trial.

PURPOSE: To compare the effectiveness of active versus sham photobiomodulation therapy (PBMT) on time to graduation and bone healing in military trainees with lower extremity bone-stress injuries (BSI).

MATERIALS AND

METHODS

Participants were trainees at the Medical Education and Training Campus, San Antonio, Texas, with MRI-confirmed metatarsal and/or tibial BSI, enrolled between June 2023 and November 2024. All participants received standard-of-care treatment and were randomized to active or sham PBMT. The primary outcome was time to graduation (days), analyzed with a cause-specific Cox model. Secondary outcomes, assessed at four months, were on-time graduation (yes/no), the Defense and Veterans Pain Rating Scale (DVPRS), the Lower Extremity Functional Scale (LEFS), and bone healing on MRI.

RESULTS

103 participants were randomized; 97 included in the final analysis. The mean age (SD) was 23.7 (4.2) years, 52.6% female. Both extremities were affected in 47.4% of the cohort; the tibia in 70.1% and a metatarsal in 28.9% (1.0% both), with BSI severity ranging from Fredericson grade I to IVb. Only 37.1% of participants graduated on time. Time to graduation did not differ between treatment groups (Hazard Ratio for Sham versus Treatment 0.95; 95%CI 0.61 to 1.48; p = 0.83) nor did on-time graduation (Risk Ratio 0.91; 95%CI 0.54 to 1.52; p = 0.71) or BSI healing on MRI (Risk Ratio 0.89; 95%CI 0.68 to 1.16; p = 0.54). Furthermore, sex, laterality, and BSI location did not predict successful on-time graduation. Pain (mean difference [95%CI] -0.74 [-2.31 to 0.83]; p = 0.84) and function (5.95 [-7.92 to 19.81]; p = 0.89) were not significantly different at 4 months.

CONCLUSION

Time to graduation, bone healing, pain intensity, and physical function did not differ significantly between trainees with BSI who received PBMT versus sham. Given the substantial resource investment, these results should be weighed when considering routine use of PBMT to manage BSIs in this setting.

TRIAL REGISTRATION: ClinicalTrials.gov # NCT05843864.