When Can I Trust The Robot? An Algorithm for CT-Based Robotic-Assisted Total Hip Arthroplasty

Area of Science:

• Orthopedic Surgery
• Robotics in Medicine
• Surgical Navigation

Background:

• Robotic-assisted total hip arthroplasty (THA) offers clinical benefits like reduced dislocation and improved implant longevity.
• Surgeon variability with robotic systems can lead to inconsistent THA outcomes.
• Accurate acetabular registration is crucial for predictable robotic-assisted hip replacement.

Purpose of the Study:

• To analyze registration errors in robotic-assisted total hip arthroplasty (THA) using MAKOplasty®.
• To develop and implement a registration algorithm to improve accuracy.
• To reduce discrepancies between preoperative plans and postoperative outcomes in THA.

Main Methods:

• Retrospective review of 100 consecutive MAKOplasty® THA cases to identify registration errors.
• Development of a registration algorithm based on initial error analysis.
• Implementation of the algorithm in the next 100 THA cases, with subsequent data review.

Main Results:

• Initially, 13% of THA cases had registration errors, requiring repeat registration or resulting in postoperative discrepancies.
• Type I (initial) and Type II (fine point) registration errors were identified.
• Post-algorithm implementation, the discrepancy rate between planned and executed acetabular cup position decreased from 13% to 0%.

Conclusions:

• A detailed method for examining registration errors in robotic-assisted THA was established.
• A successful algorithm was developed to ensure accurate acetabular registration.
• The algorithm enhances surgeon confidence and the safety and efficacy of robotic-assisted total hip replacement.