Total Hip Arthroplasty with Robotic Arm Assistance for Precise Cup Positioning: A Case-Control Study

Area of Science:

• Orthopedic Surgery
• Robotics in Medicine
• Biomechanical Engineering

Background:

• Accurate acetabular prosthesis positioning is crucial for successful total hip arthroplasty (THA).
• Conventional THA techniques can be limited by surgeon-dependent variability in implant placement.
• Robot-assisted surgery offers potential for enhanced precision in orthopedic procedures.

Purpose of the Study:

• To compare the precision of acetabular cup positioning between robot-assisted THA and conventional THA.
• To evaluate the impact of robot-assisted THA on leg length discrepancy (LLD) and other surgical outcomes.
• To assess the learning curve associated with robot-assisted THA procedures.

Main Methods:

• A randomized study included 93 patients with osteonecrosis of the femoral head or developmental dysplasia of the hip.
• Patients were assigned to either robot-assisted THA (MAKO system) or conventional THA.
• Surgical duration, cup positioning (Lewinnek's safe zone), LLD, hip offset, and Harris Hip Score were compared between groups.

Main Results:

• Robot-assisted THA showed a learning curve of 13 cases, with initial longer operation times.
• No significant difference in operative bleeding or proportion of prostheses in Lewinnek's safe zone was observed.
• Significantly smaller leg length discrepancy (LLD) was achieved with robot-assisted THA (p < 0.001).

Conclusions:

• Robot-assisted THA, utilizing the MAKO system, improves the accuracy of acetabular implant placement.
• This robotic approach leads to a significant reduction in leg length discrepancy compared to conventional THA.
• Robot-assisted THA shows promise for enhancing surgical precision and patient outcomes in hip replacement.