A study of a collected series of femoral neck fractures in seventy-one children observed for one to nineteen years shows:
1. This injury is rare but occurs in children of all ages from three to sixteen years old.
2. The fractures may be classified as transepiphysial, transcervical (the commonest), basal and pertrochanteric. Displacement was frequent.
3. The fracture usually followed severe violence, especially falls from a height or motor accidents.
4. Complications were frequent and included avascular necrosis, delayed union (seventeen cases), non-union (seven cases) and disturbances of growth at both the upper and lower ends of the femur.
5. Avascular necrosis occurred in thirty patients (42 per cent). Three patterns of necrosis are described : diffuse, localised and confined to the femoral neck. The radiographic appearances of avascular necrosis after this fracture are different from those of pseudocoxalgia (Legg-Calvé-Perthes' disease).
6. Non-union did not occur after adequate primary internal fixation or after primary subtrochanteric osteotomy.
7. The management of an undisplaced fracture presented no great problem and the results were good. A plaster spica is recommended for treatment of this fracture. Exceptionally, avascular necrosis developed.
8. Treatment of the displaced fractures (forty-nine cases) was less satisfactory. A good result was obtained from primary treatment in only fifteen patients.
9. The value of different methods of primary treatment is discussed, including manipulative reduction and immobilisation in a plaster spica, manipulative reduction and internal fixation, and primary subtrochanteric osteotomy. Manipulative reduction and immobilisation in a plaster spica is not recommended.
10. Salvage operations were required in nineteen patients. Late subtrochanteric osteotomy is of value in the management of some of these problems.