Open Reduction and Internal Fixation of a Displaced Femoral Neck Fracture
This procedure is used in younger people for treatment of a displaced femoral neck fracture that cannot be sufficiently realigned via closed reduction. This is because in younger people, it is better to maintain the femoral head if possible. The procedure is not common in older adults suffering from a displaced femoral neck fracture, as total or partial hip replacement is the treatment of choice for this population.
Open reduction and internal fixation is a two part procedure. In the first part, the goal is to reduce the fractured femoral neck, or in other words, place the fractured pieces back in proper alignment. The second part of the surgery involves stabilizing the reduced fracture. This ensures that the fracture position is maintained during the healing process so the bone heals correctly. Stabilization must be performed in a particular way so the blood supply to the femoral head is maintained.
An open procedure, as the name implies, means that surgical dissection is performed down to the fracture site to allow for direct visualization of the fracture and to facilitate putting the fracture fragments back in their original anatomic position. An open procedure is performed instead of a closed reduction if the fracture is complex. This is because a complex fracture cannot be reduced without exposing the bone to directly put the bone fragments back together.
The second component of the procedure is internal fixation of the fracture which can be accomplished in various ways. One method of internal fixation is the use of a series of screws as is seen in a standard hip pinning (figure 1). A dynamic hip screw can also be used often in conjunction with a second screw added to the femoral neck to prevent the fracture fragments from rotating. In some patients, the displaced femoral neck fracture will be so unstable that it tends to displace even after it has been placed back into position. In this situation, the surgeon may need to use a small plate and a few screws across the femoral neck fracture site to hold the fractured pieces in place. This is followed by definitive fixation either with a standard hip pining of the femoral neck fracture or occasionally through the use of a dynamic hip screw if more stability is required.
Figure 1: X-ray showing the placement of hardware in a hip pinning
Lower extremity mobilization usually occurs the day after surgery to prevent stiffness and minimize the risk of deep vein thrombosis. Individuals remain non-weight-bearing or very limited with weight-bearing for 6 weeks or longer after surgery to minimize the risk of non-union or avascular necrosis (bone death due to loss of blood supply) of the femoral head. Formal physical therapy is typically started only after adequate healing of the femoral neck fracture has been documented. However, gentle range of motion exercises for the hip joint can be initiated early in the recovery. To help manage post-surgical pain, pain medications such as NSAIDs may be used as needed. Overall, it may take several months for the fracture to fully heal as this requires new bone formation, which can be a slow process.
Potential complications from open reduction and internal fixation of a displaced femoral neck fracture include:
- Avascular necrosis (bone death) leading to secondary development of hip arthritis
- Nonunion (failure of the fractured pieces to join)
- Malunion (irregular joining of the fractured pieces)
- Infection of the surgical site
- Painful hardware