What Is The Optimal Timing And Technique For Performing A Periacetabular Osteotomy In A Patient With A Tonnis Grade 2 Hip Dysplasia, And How Can I Minimize The Risk Of Intraoperative Femoral Nerve Injury While Still Achieving Sufficient Acetabular Reorientation To Restore A Normal Acetabular Index And Improve Patient Outcomes?
Optimal Timing and Technique for Periacetabular Osteotomy (PAO) in Tonnis Grade 2 Hip Dysplasia
Optimal Timing:
- Early Intervention: Perform PAO when the patient is young, as bone quality and cartilage health are better, leading to improved outcomes.
- Disease Severity: Optimal in Tonnis grade 2, where joint narrowing is mild, and osteophytes are minimal, to prevent progression to severe osteoarthritis.
Surgical Technique:
- Procedure Selection: Use the Bernese PAO technique, which involves precise osteotomies to allow acetabular repositioning.
- Steps:
- Imaging and Planning: Utilize 3D CT scans to plan cuts and repositioning accurately.
- Surgical Exposure: Use an appropriate incision to balance exposure and minimize nerve risk.
- Osteotomies and Mobilization: Make controlled cuts to free the acetabulum, then mobilize and reposition it.
- Repositioning: Aim to restore a normal acetabular index (0-10 degrees) through anterior and lateral rotation.
- Fixation: Secure the acetabulum with screws to maintain the new position.
Minimizing Femoral Nerve Injury:
- Nerve Monitoring: Use intraoperative nerve monitoring to reduce injury risk.
- Surgical Technique: Careful dissection and gentle handling near the femoral nerve.
- Patient Positioning: Avoid hyperextension and keep the hip flexed to reduce nerve tension.
- Incision Strategy: Balance minimally invasive approaches with adequate exposure to protect nerves.
Post-Operative Care:
- Rehabilitation Plan: Implement a structured program to avoid harmful positions and promote healing.
- Patient Education: Emphasize the importance of adherence to post-operative instructions to protect the hip.
Conclusion: PAO is most effective in young patients with Tonnis grade 2 hip dysplasia. The Bernese technique, with careful planning and execution, can restore acetabular alignment while minimizing complications like femoral nerve injury. Attention to detail in both surgical technique and post-operative care is crucial for optimal outcomes.