Computed tomographic analysis of curved and straight guides for placement of suture anchors for acetabular labral refixation.

ABSTRACT

PURPOSE: The purpose of this study was to compare suture anchor placement in the acetabular rim between straight and curved drill guides regarding angle and distance of the suture anchor tip from the articular cartilage during labral refixation. METHODS: A total of 14 fresh-frozen cadaveric hips underwent arthroscopic labral incision from the 12 to 3 o'clock positions and subsequent repair with either a curved drill guide or a straight drill guide. These hips were then compared by computed tomographic imaging analysis by measuring the angle of suture anchor insertion and the distance of the tip of the suture anchor to the articular cartilage at the 1 o'clock, 2 o'clock, and 3 o'clock positions. RESULTS: The curved suture anchor (CSA) guide significantly increased the insertion angle (P = .009) and distance from the articular cartilage to anchor (P = .003) at the 1 o'clock position on the acetabulum. The angle of insertion at the 2 and 3 o'clock positions was greater for the CSA guide compared with the straight suture anchor (SSA) guide but did not reach statistical significance. CONCLUSIONS: A CSA guide was shown to be significantly more effective in increasing the angle of insertion of suture anchors and increased the distance of the suture anchor tip to the articular cartilage surface at the 1 o'clock position but not at the 2 or 3 o'clock position. CLINICAL RELEVANCE The use of SSA guides can be difficult because of the osseous morphologic characteristics of the acetabular rim, leading to placement of the suture anchor away from the acetabular rim and therefore resulting in a nonanatomical refixation of the acetabular labrum. The use of a curved guide, flexible drill, and flexible suture anchor inserter may provide more precise placement of suture anchors in the acetabular rim.