In general, fractures of the femoral head are associated with dislocation of the hip. In 90% the dislocations are posterior and in 10% anterior. An unreduced dislocation is an emergency because it threatens the blood supply to the head and it may also be accompanied by pressure on a major nerve. Therefore, a reduction must be done as an emergency. If a closed reduction succeeds, one has the luxury of time to investigate the patient further with a CT and then evolve an appropriate treatment rationale. If a closed reduction fails, an emergency open reduction must be undertaken. Small fragments which do not involve the weight bearing portion of the head may be considered for primary resection, particularly if they block an anatomical reduction of the hip.
If a large fragment blocks an anatomical reduction of the hip, under emergency conditions one may consider cutting the ligamentum teres to which the fragment is often still attached, and then securing its fixation trough the articular surface as illustrated. If the hip reduces, but on a CT the fragment is large or incompletely reduced, then it would be fixed through an anterior approach. Once again, transarticular fixation is often necessary.
Reduce the fragment directly and maintain reduction with pointed forceps.
Prior to definitive fixation with screws, secure the fragment with a K-wire.
Definitive fixation of the fragment
The fragment is fixed with either recessed small cancellous lag screws, or headless compression screws (Herbert screws).
Number and size of screws
Choose the screws long enough so that the thread does not cross the fracture line. A single screw does not provide rotational stability. If the size of the fragment allows, use two screws.
5. Postoperative treatment
Since the fractures are articular, non weight bearing is advised until union which is complete usually between 8-12 weeks. Range of motion exercises are started as soon as possible to prevent joint stiffness.
Prognosis of split fractures of the femoral head (Pipkin)
The outcome of these injuries remains unpredictable even after anatomical joint restoration.