Do capacitively coupled electric fields accelerate tibial stress fracture healing?

Abstract

Background: Tibial stress fractures increasingly affect athletes and military recruits, with few known effective management options. Electrical stimulation enhances regular fracture healing but the effect on stress fractures has not been definitively tested. Hypothesis: Capacitively coupled electric field stimulation (CCEFS) will accelerate tibial stress fracture healing. Study design: Double blind, randomized controlled clinical trial. Methods: 20 men and 24 women with acute posteromedial tibial stress fracture were referred from local clinicians. Subjects were randomly assigned active or placebo CCEFS to be applied for 15 hours per day until healed, given supplemental calcium and instructed to rest from provocative training. Healing was confirmed when hopping to 10 cm for 30 seconds could be achieved without pain. Results: No difference in time to healing was detected between treatment and placebo groups. Females in the treatment group healed more slowly than males (p = 0.05). Superior treatment compliance was associated with reduced time to healing (p = 0.003). Rest non-compliance was associated with increased time to healing (p = 0.05). Conclusions: Whole group analysis did not detect an effect of CCEFS on tibial stress fracture healing, however, greater device use and less weight bearing loading enhanced the effectiveness of the active device. More severe stress fractures healed more quickly with CCEFS. Clinical relevance: While the use of CCEFS for tibial stress fracture healing may not be efficacious for all, it may be indicated for the more severely injured or elite athlete/recruit whose incentive to return to activity may motivate superior compliance.