Two-Tiered Resection of Cam Lesions in Hip Femoroacetabular Impingement: Optimizing Femoral Head Sphericity

ABSTRACT: Hip arthroscopy is one of the most rapidly growing fields in orthopaedic surgery. One of the most frequent pathologies treated with hip arthroscopy remains femoroacetabular impingement, which is addressed by labral repair and femoral osteoplasty. The most commonly cited reason for failure of arthroscopic treatment of femoroacetabular impingement is under-resection of the cam lesion. Surgeons frequently use evaluations of preoperative images, intraoperative fluoroscopy, and dynamic range of motion to ensure adequate resection. In this article, we describe a reproducible and standardized technique to assist in appropriate resection. This is achieved by a 2-tiered resection technique: Tier 1 aims to set the depth of resection and restore the head-neck offset. Tier 2 then matches the depth of the resection set by tier 1 and allows for retention of appropriate transition of the proximal convexity to the distal concavity seen in more ideally shaped femoral heads. With this technique, we offer a tool to avoid under-resection in the area of maximal conflict while simultaneously minimizing the risk of proximal over-resection and thus compromising the fluid seal dynamics of the joint in deeper flexion angles. Technique Video Video 1 Visualization of femoral osteoplasty from distal anterolateral portal. The resection begins with visual inspection and localization of important anatomy including the lateral retinacular vessels. The osteoplasty ensues in a 2-tiered manner. The tier 1 resection is begun 1.5 burr widths distal to the articular surface margin with the goal to create the depth of resection required to re-create the native head-neck offset. This is also confirmed with fluoroscopic imaging from the Dunn lateral view to identify the physeal scar as the proximal extent of the osteoplasty. During the tier 1 resection, the proximal head-neck junction is contoured to achieve sphericity. The tier 2 resection is then begun distal to tier 1 with the goal of matching the depth and resecting the remainder of the cam. Finally, attention is turned back to the head-neck junction with the goal of creating a smooth, spherical head via gentle contouring. During the resection, multiple views through the distal anterolateral portal are used to gather a greater perspective of the resection. At the completion of the procedure, evaluation of dynamic hip range of motion under direct visualization, along with fluoroscopic imaging, is used to ensure adequate resection of the cam lesion.

SUBMITTER: Haase L 

PROVIDER: S-EPMC9353533 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature