Femoral head vitality in femoral neck fracture after hook-pin internal fixation.

Femoral head vitality was evaluated by tetracycline labeling and 99mTc-MDP scintimetry in 317 femoral neck fractures before and after internal fixation with two hook-pins. The preoperative vitality was about the same as that observed by others using comparable methods. The postoperative vitality was reduced in five of 81 undisplaced fractures and in 76 of 236 displaced fractures. These data would predict a rate of avascular healing complications of 7% in undisplaced and 32% in displaced fractures treated with hook-pins.