Safe Sex After Total Hip Arthroplasty: Using Computed Tomography-Based Robotics to Evaluate "At-Risk" Sexual Positions

Background: Total hip arthroplasty (THA) can improve sexual satisfaction, but fear of dislocation can lead to sexual difficulties following this procedure. Previous kinematic research identified 4 sexual positions in women and 2 in men that were considered at risk for impingement. This study aimed to validate these findings using current robotic THA simulations.

Methods: The 3-dimensional renderings from 12 patients who received computed tomography (CT)-based robotic THA were used to assess for prosthetic and/or bony impingement among 12 popular sexual positions. There were 9 cup orientations tested for each position (a combination of anteversion [0 °, 15 °, and 30 °] and inclination [40 °, 45 °, and 60 °]). The at-risk positions were tested again using the unique hip positions and cup orientations where previous geometric modeling data found impingement to occur.

Results: Using mean hip positions, impingement occurred in at least 1 patient in 1 of the 12 positions for women (position 5) and 5 of the 12 positions for men (positions 1, 5, 8, 10, and 11). Among the at-risk positions, impingement occurred in none of the 2 at-risk women positions (0 of 17 cup orientations) and in both at-risk men positions (9 of 9 cup orientations for position 8 and 1 of 1 for position 11).

Conclusion: Recreating popular and at-risk sexual positions following THA with a CT-based robotics system yielded results that were inconsistent with previous geometric modeling data. Resolving these discrepancies is crucial for surgeons to provide accurate postoperative patient education. The CT-based robotic systems may provide necessary input to feasibly individualize such recommendations, but current limitations in CT-based robotics require continued attention and innovation.