The Prevalence of Cam Morphology: A Cross-Sectional Evaluation of 3,558 Cadaveric Femora

• Main Authors: Shane Hanzlik, Andrew J. Riff, Thomas H. Wuerz, Michael Abdulian, Danielle Gurin, Shane J. Nho, Michael J. Salata
• Format: Article
• Language: English
• Published: Frontiers Media S.A. 2021-01-01
• Series: Frontiers in Surgery
• Subjects: hip; FAI; femoroacetabular impingement; hip arthroscopy; cadaveric
• Online Access: https://www.frontiersin.org/articles/10.3389/fsurg.2020.588535/full

Purpose: We sought to determine (1) the prevalence of cam deformity in the population and that of bilateral cam deformity, (2) the typical location of a cam lesion, and (3) the typical size of a cam lesion by direct visualization in cadaveric femora.Methods: Two observers inspected 3,558 human cadaveric femora from the Hamann–Todd Osteological Collection from the Cleveland Museum of Natural History. Any asphericity >2 mm from the anterior femoral neck line was classified as a cam lesion. Once lesions had been inspected, the prevalence in the population, prevalence by gender, and prevalence of bilateral deformity were determined. Additionally, each lesion was measured and localized to a specific quadrant on the femoral neck based upon location of maximal deformity.Results: Cam lesions were noted in 33% of males and 20% of females. Eighty percent of patients with a cam lesion had bilateral lesions. When stratified by location of maximal deformity, 90.9% of lesions were in the anterosuperior quadrant and 9.1% were in the anteroinferior quadrants. The average lesion measured 17 mm long × 24 mm wide × 6 mm thick in men and 14 mm × 22 mm × 4 mm in women (p < 0.05).Conclusions: The population prevalence of cam deformity determined by direct visualization in cadavers may be higher than has been suggested in studies utilizing imaging modalities.Level of Evidence : Level II, diagnostic study.