INTRACAPSULAR HIP FRACTURE YOUNG PATIENT

These are the radiographs for a 36yearold cyclist hit by a car. It is an isolated injury.

Describe the xrays.

These are AP and lateral radiographs of the left hip showing a displaced intracapsu lar fracture of the neck of the femur.

Describe the blood supply to the femoral head and explain why this is important.

The blood supply to the femoral head comes from three groups of vessels. First, an extracapsular arterial ring at the base of the femoral neck formed from the medial and lateral circumflex femoral arteries. Ascending arterial vessels arising from the extraarticular ring and passing proximally on the femoral neck form a retinacular

supply in close proximity to the bony surface of the femoral neck. Second, an arterial supply in the ligament of Teres, which may atrophy over time and therefore becomes less important with age although there is often some persistent supply. Finally, the femoral head also has an intraosseous blood from nutrient blood vessels.

Therefore, in a femoral neck fracture, the intraosseous blood supply to the femoral head is disrupted and the remaining supply may be provided only by the remaining retinacular vessels. Increasing displacement of the fracture may indicate increasing energy of injury and likelihood of disruption to these vessels so that dis placed femoral neck fractures have a greater chance of rendering the femoral head avascular than undisplaced fractures.

How would you manage this injury and patient?

A femoral neck fracture in a young patient often represents a highenergy injury and the patient should be treated along ATLS principles. Assuming this is an isolated injury, I would plan to treat the hip fracture urgently to try to minimise the period of ischaemia to the femoral head. In a young patient with reasonable bone quality, conserving the native femoral head avoids the risks and longterm consequences of arthroplasty. There is debate as to whether the use of a formal capsulotomy might reduce the local tamponade effect of the haematoma on the femoral head and the resulting risk of avascular necrosis. There is no good evidence to support this and it is not something that I would do routinely. I would choose to manage this patient with closed reduction of the fracture and internal fixation. There is debate as to whether cannulated screws or a sliding hip screw device and plate provide ideal fixa tion. In a young patient I would choose to use a sliding hip screw because it resists shear forces better, particularly in more vertical (Pauwel 3) fracture types. I would use a standard lateral approach if the fracture reduced satisfactorily and easily with a closed approach. If closed reduction is difficult or unsatisfactory, I would proceed to an open reduction using the anterolateral Watson–Jones approach. This would allow me to visualise and adjust the fracture reduction, to temporarily stabilise the fracture with Kwires to avoid subsequent rotation and to fix the fracture with a slid ing hip screw all through the same incision. This also gives me the option of placing an additional cannulated antirotation screw over the initial Kwire for additional rotational stability.

Would you impose any limitations on the patient, how long would you follow them up for and what would you tell them about the relative merits and risks of the different treatment options?

I would tell the patient that this is a serious injury with potential longterm con sequences. Any form of hip fracture surgery carries risks including scar, infec tion, DVT, and neurovascular injury. The management choice is mainly whether to fix or replace the fracture. My advice would be that in a young, active patient with relatively high demands, fixing the fracture rather than performing a form of replacement surgery conserves the patient’s own bone and avoids the complications associated with arthroplasty such as dislocation, bearing wear and periprosthetic fracture. Fracture fixation does carry risks of nonunion as well as painful post traumatic arthritis, failure of fixation and avascular necrosis. With these in mind, I would undertake urgent surgery, up until the early hours of the same evening of presentation or first thing the next day, but not in the middle of the night. I would limit the patient to toetouch weight bearing for 6 weeks postoperatively and I would