SPONTANEOUS SUBCAPITAL FEMORAL-NECK FRACTURE AFTER HEALED TROCHANTERIC FRACTURE

Two hundred thirty-three patients with an unstable trochanteric hip fr acture were randomized prospectively for stabilization with a fixed an gle blade plate or a compression hip screw. Twenty patients had the im plant removed after the fracture was healed (average, 20.5 months; ran ge, 12-42 months). In seven of these 20 patients, a spontaneous fractu re of the femoral neck occurred at an average of 19 days after implant removal. Four of the these seven patients had been treated with the f ixed angle blade plate and three with the sliding screw plate. The his tologic examination of three specimens was inconclusive. The authors h ave not observed subcapital fracture among patients whose implants wer e not removed. The mechanism behind this complication is unknown.