Pulse low-intensity electromagnetic field as prophylaxis of heterotopic ossification in patients with traumatic spinal cord injury

Heterotopic ossification (HO) is an important complication of head and spinal cord injuries (SCI). Pulse low-intensity electromagnetic field (PLIMF) therapy increases blood flow to an area of pain or inflammation, bringing more oxygen to that area and helps to remove toxic substances. The aim of this study was to determine the effect of PLIMF as prophylaxis of HO in patients with SCI.

This prospective random control clinical study included 29 patients with traumatic SCI. The patients were randomly divided into experimental (n=14) and control group (n=15). The patients in the experimental group, besides exercise and range of motion therapy, were treated by PLIMF of the following characteristics: induction of 10 mT, frequency of 25 Hz and duration of 30 min. Pulse low-intensity electromagnetic field therapy started in the 7th week after the injury and lasted 4 weeks. The presence or absence of HO around the patients hips we checked by a plane radiography and Brookers classification. Functional capabilities and motor impairment were checked by Functional Independent Measure (FIM), Barthel index and American Spinal Injury Association (ASIA) impairment class. Statistic analysis included Kolmogorov-Smimrnov test, Shapiro-Wilk test, Mann Whitney Exact test, Exact Wilcoxon signed rank test and Fischer Exact test. Statistical significance was set up to p<0.05.

At the end of the treatment no patient from the experimental group had HO. In the control group, five patients (33.3%) had HO. At the end of the treatment the majority of the patients from the experimental group (57.14%) moved from ASIA-A to ASIA-B class.

Pulse low-intensity electromagnetic field therapy could help as prophylaxis of HO in patients with traumatic SCI.