Malreduction and Avascular Necrosis in Subcapital Fractures of the Femur

The long-term results in a consecutive series of 323 healed subcapital fractures of the femur show that, with few exceptions, the capital fragment maintains its integrity when the fragments are aligned within the narrow limits of good reduction, but undergoes superior segmental collapse when reduction is poor. 2. The effect of malreduction on the congruity of the hip joint is examined, and a remodelling response to malalignment of the aspherical femoral head in the imperfectly round acetabulum is proposed as an alternative interpretation of the radiological changes now considered to be the result of capital ischaemia.