Sciatic nerve injury in total hip resurfacing: a biomechanical analysis

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Neuroscience

Background:

• Sciatic nerve palsy is a potential complication of total hip resurfacing (THR) via a posterior approach.
• Understanding intraoperative nerve pressures is crucial for preventing iatrogenic injury.

Purpose of the Study:

• To investigate the influence of gluteal sling status and knee positioning on sciatic nerve pressure during acetabular exposure and hip reduction in posterior THR.
• To identify surgical modifications to minimize sciatic nerve risk.

Main Methods:

• Utilized cadaveric models to simulate posterior THR.
• Measured sciatic nerve pressures during acetabular exposure and hip reduction under varying gluteal sling conditions and knee positions.
• Analyzed pressure data relative to a predefined injury threshold.

Main Results:

• Gluteal sling condition significantly impacted sciatic nerve pressure during acetabular exposure.
• Knee position did not significantly affect nerve pressure during acetabular exposure.
• Knee positioning became significant during hip reduction, influencing sciatic nerve pressures.
• Nerve pressures remained below injury levels during femoral preparation regardless of positioning.

Conclusions:

• Releasing the gluteal sling during posterior THR may mitigate sciatic nerve injury risk.
• Partial knee flexion during hip reduction warrants consideration to further reduce nerve pressure.
• These findings can inform surgical technique to improve patient safety in posterior THR.