What is the detailed step‑by‑step procedure for a total hip arthroplasty using the lateral (Hardinge) approach?

Total Hip Replacement via Lateral (Hardinge) Approach: Step-by-Step Procedure

The lateral (Hardinge) approach for total hip arthroplasty involves splitting the anterior one-third of the gluteus medius and vastus lateralis in continuity, providing excellent exposure with low dislocation rates (0.3%), though it carries a 10-33% risk of residual abductor weakness. 1, 2

Pre-operative Preparation

Patient Optimization

• Administer pre-operative exercise and education programs to facilitate early postoperative rehabilitation 3
• Give paracetamol and NSAIDs (or COX-2 inhibitors) pre-operatively or intra-operatively as part of the basic analgesic regimen 3

Anesthesia Selection

• Use either spinal or general anesthesia (both are equally recommended) 3
• Administer intravenous dexamethasone 8-10 mg intra-operatively for analgesic and anti-emetic effects 3
• Consider fascia iliaca block or local infiltration analgesia, particularly in patients with contraindications to basic analgesics or those expected to have high postoperative pain 3
• If spinal anesthesia is used, intrathecal morphine 0.1 mg may be considered, though risks must be weighed against benefits 3

Patient Positioning

• Position the patient in lateral decubitus position with the operative hip uppermost
• Secure the patient with appropriate supports to maintain stability during the procedure 1

Surgical Technique

Incision

• Make a straight lateral incision centered over the greater trochanter, typically 10-15 cm in length (minimally invasive modifications can reduce this to approximately 10 cm) 4
• The incision extends proximally along the femoral shaft and distally in line with the femur 5, 1

Approach to the Hip Joint

Critical Step - Gluteus Medius Split:

• Identify and split only the anterior one-third of the gluteus medius muscle fibers in line with their direction 1
• Keep these anterior gluteus medius fibers in continuity with the vastus lateralis muscle - this is the key modification that distinguishes the Hardinge approach 5, 1
• The split should begin at the tip of the greater trochanter and extend proximally 1

Common Pitfall: Splitting more than the anterior one-third of the gluteus medius significantly increases the risk of postoperative abductor weakness (up to 33% at one year) 2. Limiting the split to the anterior third reduces this complication while maintaining adequate exposure 1.

Capsular Exposure and Opening

• Elevate the anterior gluteus medius and vastus lateralis as a continuous sleeve from the greater trochanter and proximal femur 1
• Incise the hip joint capsule in a T-shaped or cruciate fashion to expose the femoral head and acetabulum 5
• Excise the capsule as needed for adequate visualization 1

Femoral Head Dislocation

• Flex, adduct, and externally rotate the hip to dislocate the femoral head anteriorly 5
• This maneuver brings the femoral neck into the surgical field 1

Femoral Neck Osteotomy

• Perform the femoral neck osteotomy at the predetermined level based on pre-operative templating
• Remove the femoral head and place it on the back table for potential use as bone graft 1

Acetabular Preparation

• Expose the acetabulum by placing retractors around the acetabular rim (anterior, posterior, and inferior)
• Remove the labrum and any remaining capsular tissue from the acetabular rim
• Ream the acetabulum sequentially with progressively larger hemispherical reamers until bleeding subbone is reached
• Position the acetabular component at 40 degrees of abduction (mean angle demonstrated in studies) 6
• Impact or screw-fix the acetabular component depending on the implant design and bone quality 1
• Insert the acetabular liner 1

Femoral Preparation

• Elevate the proximal femur using a bone hook or femoral elevator to deliver it into the wound
• Open the femoral canal with a box chisel or awl at the piriformis fossa
• Sequentially broach the femoral canal to the appropriate size based on pre-operative templating
• Achieve neutral-to-valgus femoral stem position (demonstrated as optimal in outcome studies) 6
• Perform trial reduction to assess leg length, offset, and stability
• Insert the definitive femoral component (cemented or uncemented based on bone quality and patient factors) 4
• Place the femoral head on the trochanter 1

Reduction and Stability Assessment

• Reduce the hip joint and assess stability through full range of motion
• Confirm appropriate leg length and offset 1

Closure

Muscle and Soft Tissue Repair

• Perform transosseous refixation of the anterior gluteus medius and vastus lateralis sleeve back to the greater trochanter using heavy non-absorbable sutures through bone tunnels 4
• This repair is critical to minimize postoperative abductor weakness 2
• Ensure secure reattachment to restore abductor function 1

Important Consideration: The quality of this repair directly impacts postoperative abductor strength. Studies show 10% of patients have moderate-to-severe limp at 2 years, reduced to 4% in patients with unilateral disease only 1. Meticulous repair technique is essential 2.

Wound Closure

• Close the fascia lata and subcutaneous tissues in layers
• Close the skin with staples or sutures 1

Postoperative Pain Management

• Continue paracetamol and NSAIDs (or COX-2 inhibitors) postoperatively as the foundation of pain control 3
• Reserve opioids as rescue analgesics only to minimize side effects 3
• Avoid epidural analgesia, femoral nerve block, lumbar plexus block, and gabapentinoids as adverse effects outweigh benefits in this procedure 3

Key Advantages and Complications

Advantages of the Lateral Approach

• Extremely low dislocation rate of 0.3% compared to posterior approaches 1
• Excellent surgical exposure without requiring trochanteric osteotomy 1, 6
• Acceptable operative times once the learning curve is mastered 5, 6
• Allows accurate component placement 1

Complications to Monitor

• Abductor weakness occurs in 10-33% of patients, with higher rates when more than the anterior third of gluteus medius is split 2, 1
• Heterotopic ossification develops in fewer than 3% (Brooker grade III/IV), rarely functionally limiting 1
• Sciatic nerve palsy is rare but possible 1
• The approach has a learning curve that must be mastered for optimal outcomes 5

Clinical Note: While this approach is more technically demanding than the posterior approach, the dramatically reduced dislocation rate (0.3% vs. significantly higher rates with posterior approaches) makes it particularly valuable for fractured neck of femur cases where dislocation risk is otherwise unacceptably high 5.