The effects of pulsed electromagnetism on fresh fracture healing: osteochondral repair in the rat femoral groove.

Some clinical studies have claimed significant reductions in the healing time of fresh fractures with the use of pulsed electromagnetic fields (PEMFs). Animal models, however, have produced more equivocal results. This investigation examined the effects of PEMF treatment on an osteochondral defect placed in the patellofemoral groove of the rat. The results indicated that PEMF enhances early vascular reaction and suppresses initial pannus proliferation. Early chondrogenesis and bone formation were consistently stimulated, and the restoration of normal bone trabeculae advanced. Pulsed electromagnetic field treatment therefore may be useful in advancing repair during the early proliferative stage. Later results were variable and suggest that prolonged use may have deleterious effects, enhancing chondrogenesis beyond a point observed in normal repair and thus delaying normal subsurface trabeculation.