Cadaveric Evaluation of Anchor Perforation During Hip Labral Repair: Influence of Portal Location and Drill Guide.

Background: Acetabular labral tears are frequently treated with arthroscopic repair using suture anchors. Iatrogenic chondral injury may occur during predrilling for suture anchors owing to factors such as portal location and drill guide type. Purpose/Hypothesis: The purpose of this study was to evaluate the effect of portal location and use of straight versus curved drill guides on drill perforation rates of the acetabular subchondral bone and outer cortex. It was hypothesized that curved guides and distal portals would minimize these perforation rates. Study Design: Controlled laboratory study. Methods: Nine cadaveric acetabula were marked at specific clockface positions (3:00 to 11:00) and drilled through anterior, anterolateral, and distal anterolateral accessory (DALA) portals using straight and curved guides. Ninety drill holes were analyzed for subchondral and cortical perforations. Statistical analysis included Fisher exact test and regression modeling. Results: A total of 90 acetabular suture anchor drill holes were created using each combination of portal (anterior, anterolateral, DALA), drill guide (curved, straight), and clockface position on the acetabulum. Among 90 drillings, 7 (7.8%) perforated the subchondral bone, and 10 (11.1%) perforated the outer cortex. Out of 45 drillings performed with a straight drill guide, 6 (13.3%) perforated the subchondral surface, as opposed to 1 (2.2%) with a curved drill guide. Of 30 drillings conducted via the anterolateral portal, 5 (16.7%) perforated the subchondral surface, as compared with 1 (3.3%) drilled from the DALA or anterior portal. Multiple linear regression based on portal, drill guide, and clockface position did not predict subchondral perforation (R 2 = 0.08; P = .35) or outer cortical perforation (R 2 = 0.04; P = .35). Conclusion: The use of anterior and DALA portals minimized subchondral perforation rates but was not statistically significant. Curved guides showed a trend toward reduced perforations when compared with straight guides. Articular surface penetration was most common at the 3:00 and 11:00 positions. Clinical Relevance: This study supports the use of curved guides and distal portals to enhance safety during arthroscopic acetabular labral repair, providing actionable insights for optimizing surgical techniques.