Anterolateral Approach to the Femoral Shaft

What it exposes. The anterolateral approach gives direct access to the lateral and anterior surfaces of the femoral shaft. It allows direct visualisation for fracture reduction, application of a lateral or anterior plate, and placement of anterior bone graft. The femoral neurovascular bundle is safely medial and the approach avoids the posterior compartment structures. Primary indications. Femoral shaft fractures requiring open reduction and plate fixation; aseptic nonunion of the femoral shaft needing direct bone grafting; malunion requiring corrective osteotomy and plating; pathological fractures requiring curettage and stabilisation; and anterior bone grafting for delayed union. Why this approach is chosen. It is the workhorse exposure for femoral shaft plating whenever intramedullary nailing is not feasible (for example a narrow canal) or when direct reduction and stable plate fixation with anterior bone grafting are required. Contraindications. Active infection at the surgical site; severe soft-tissue compromise over the lateral thigh requiring an alternative exposure; patient factors precluding supine or lateral positioning; and isolated medial femoral pathology better addressed by a medial approach. Alternative approaches. A lateral approach that splits the vastus lateralis in its substance rather than elevating it from the septum; a posterior approach for posterior-cortex access or when lateral soft tissues are compromised; minimally invasive percutaneous plating when indirect reduction is acceptable; and antegrade or retrograde nailing when intramedullary fixation is preferred. Position & landmarks. The patient is supine on a radiolucent table with a small bump under the ipsilateral buttock to neutralise femoral rotation. Pad all pressure points, keep the arms abducted less than 90 degrees or tucked, and confirm full-length femur fluoroscopy in AP and lateral with a C-arm. The knee is flexed 10 to 20 degrees over a bolster to relax the quadriceps, and the leg is draped free with an optional high thigh tourniquet. The greater trochanter marks the proximal end and the lateral femoral condyle the distal end of a longitudinal lateral-thigh incision; the linea aspera is felt posteriorly once vastus lateralis is elevated, and the lateral intermuscular septum is the firm deep plane.

Work down through the layers of the lateral thigh: split the fascia lata, identify the lateral intermuscular septum, and elevate vastus lateralis anteriorly off it - systematically ligating each perforating branch of profunda femoris as it pierces the septum - until the anterolateral femur is exposed subperiosteally. The plane. There is no true internervous plane: the entire quadriceps, including vastus lateralis, is supplied by the femoral nerve. The dissection is therefore an intermuscular plane anterior to the lateral intermuscular septum. Vastus lateralis is elevated anteriorly (medially in the wound) from its septal attachment, preserving the femoral nerve branches that enter its anterior surface. Staying strictly subperiosteal on the femur is what keeps the medial femoral neurovascular bundle safe.

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Structures at risk, by layer

Extensile options. Extend proximally along the greater trochanter into the Watson-Jones interval between tensor fascia lata and gluteus medius (both superior gluteal nerve) to reach the femoral neck and subtrochanteric region for long plates or combined neck-shaft fractures. Extend distally along the lateral femoral condyle, splitting the iliotibial band and elevating vastus lateralis from the condyle, for supracondylar and distal-shaft access; this can be combined with a lateral parapatellar arthrotomy if there is intra-articular extension. Both extensions remain anterior to the intermuscular septum and protect the femoral bundle. A posterior approach is reserved for posterior-cortex comminution needing direct access. Closure. Irrigate thoroughly and achieve haemostasis. Close the fascia lata securely with interrupted absorbable suture to prevent muscle herniation, then close subcutaneous tissue and skin. Apply a sterile dressing and consider a drain if dissection was extensive. Complications

Post-operative care. Document femoral nerve function (quadriceps contraction and knee extension) on the neurovascular check. Weight bearing is touch or partial for 6 to 12 weeks depending on fracture stability and fixation, progressing on radiographic healing. Begin early passive and active-assisted knee range of motion - aim for 0 to 90 degrees by 2 weeks and full range by 6 weeks, with early quadriceps strengthening. Give DVT prophylaxis (LMWH or aspirin per institutional protocol) for a minimum of 2 to 4 weeks.

• Open reduction and plate fixation of femoral shaft fractures with a lateral or anterior plate, ideal when direct reduction and stable fixation are required.
• Anterior bone grafting for aseptic nonunion or delayed union, using the direct anterior-cortex access the exposure provides.
• Corrective osteotomy for malunion with plating.
• Curettage and stabilisation of pathological lesions of the shaft.
• Subtrochanteric fractures through the proximal Watson-Jones extension, and supracondylar and distal-femur fractures (distal femur ORIF) through the distal extension.

The anterolateral approach is the standard exposure for open plating of femoral shaft fractures when intramedullary nailing is contraindicated. Systematic perforator ligation reduces bleeding complications, and outcomes are excellent with anatomic reduction and stable fixation: anatomic reduction with less than 5 degrees of angulation and less than 1 cm shortening yields greater than 90 percent good-to-excellent results, nonunion rates fall below 5 percent when bone grafting is used for atrophic nonunions, and knee stiffness is minimised by early motion. Guidelines, registries and global practice. The approach is used worldwide for plate fixation when intramedullary nailing is not feasible, and the principles are consistent across contemporary practice and other examination systems. AO Foundation recommends anatomic reduction and stable fixation for femoral shaft fractures when plating is chosen; BOA and BOAST guidance emphasises soft-tissue handling and early mobilisation; and OTA and AAOS stress restoration of length, alignment and rotation. Femoral shaft fractures have a population incidence of approximately 10 to 15 per 100,000 per year, and plate fixation shows greater than 90 percent union when anatomic reduction is achieved. In high-resource settings locking plates and minimally invasive techniques are common, while in resource-limited settings standard compression plates and open techniques remain effective when the same principles of reduction, perforator control and stable fixation are followed. Informed consent (globally applicable) should cover bleeding from perforators, infection (1 to 3 percent), nonunion (5 to 10 percent), malunion, knee stiffness and the need for protected weight bearing for 6 to 12 weeks.