All approaches to the distal femur

The lateral approach allows for visualization, reduction, and fixation of simple articular fractures of the distal femur. More complex fractures (particularly those involving the medial femoral condyle) are better exposed with a lateral or medial parapatellar approach.

The lateral approach relies on an atraumatic elevation of the vastus lateralis from the lateral aspect of the distal femur, and a lateral arthrotomy for joint visualization. Articular reduction and lateral plate application can both be achieved with the same approach. Additionally, the approach can be extended proximally, as described in the lateral approach to the femoral shaft.

The approach can also be used without an arthrotomy if the articular surface is not fractured.

The medial approach to the distal femur is useful to expose medial distal femoral fractures, a Hoffa-type fracture. It is also useful to expose the neurovascular bundle when a distal femoral fracture is complicated by an arterial injury.

The approach can be extended to expose the posterior cruciate ligament.

This approach also allows limited access to the posterior aspect of the distal femur.

The lateral parapatellar approach provides a good view of the articular surface of the distal femur.

The lateral minimally invasive plate osteosynthesis (MIPO) approach combines a short version of the open lateral approach to the distal femur, a minimally invasive approach to the midshaft or, proximal femoral region, and small 1.0 – 1.5 cm wide stab incisions.

This approach is used for medial femoral condylar fractures. In addition, it may be used in retrograde nailing of intra articular fractures.

Most femoral nailing procedures are performed with antegrade nailing position. It is extremely successful and utilizes minimally invasive techniques.

The piriformis entry point is used for straight nails.

Most femoral nailing procedures are performed with antegrade nailing position. It is extremely successful and utilizes minimally invasive techniques.

The trochanteric entry point is used for proximally curved nails.

Care should be taken with the approach for retrograde nailing as several anatomical structures are at risk. The most important potential hazard is damage to the anterior cruciate ligament. In addition, cartilage from the weight bearing zone may be damaged if a non-anatomic approach is selected. A non-anatomic approach can also lead to a failure to reduce the fracture properly, resulting in a varus/valgus malposition of the distal main fragment. Lastly, plunging out the back of the knee is always a major risk during this procedure because of the neurovascular structures.

This page provides details on safe zones for pin insertion. Inserting percutaneous instrumentation through safe zones reduces the risk of damage to neurovascular structures.

The arthroscopic approach is only recommended in minimally, or nondisplaced, fractures in young patients. Advanced experience in arthroscopic surgery is essential.

This content is in production. Meanwhile, details for this approach can be found in the following article:

Starr A, Jones A, Reinert C: The “Swashbuckler”: A Modified Anterior Approach for Fractures of the Distal Femur. J Orthop Trauma. 1999;13:138-140.  

This content is in production. Meanwhile, details for this approach can be found in the following article:

Liebergall M, Wilbur J, Mosheiff R, et al: Gerdy’s Tubercle Osteotomy for the treatment of Coronal Fractures of the Lateral Femoral Condyle. J Orthop Trauma. 2000;14:214-215.