Michael D Hellman1, Bryan D Haughom2, Nicholas M Brown2, Yale A Fillingham2, Marc J Philippon3, Shane J Nho2. 1. Rush University Medical Center, Department of Orthopaedic Surgery, Chicago, Illinois, U.S.A.. Electronic address: mdhellman@gmail.com. 2. Rush University Medical Center, Department of Orthopaedic Surgery, Chicago, Illinois, U.S.A. 3. Steadman Clinic and Steadman Philippon Research Institute, Vail, Colorado, U.S.A.
Abstract
PURPOSE: To investigate whether pelvic incidence (PI) in patients with symptomatic femoroacetabular impingement was different from that in a normal population. METHODS: Retrospective analysis of 30 consecutive female and 30 consecutive male patients with computed tomography scans who underwent hip arthroscopy for FAI. PI was measured using scout lateral radiographs. The center-edge angle (CEA), acetabular version, and α angle were also measured. Each patient was subcategorized as having a cam-type deformity (α angle >55°), a deep socket deformity (CEA >39°), and/or a retroverted acetabulum (acetabular anteversion <15°). Our group and subgroups were compared with a historical control group from a previously published study of 300 volunteers. Each group was compared using a Student t test. RESULTS: Our mean PI was 49.31° ± 12.34° (range, 28.4°-79.5°), less than the asymptomatic historical control (n = 300) with a mean PI of 55.0° ± 10.6° (range, 33°-82°) (P < .001). The subgroups for cam deformity, deep socket deformity, and acetabular retroversion have a mean PI of 48.89° ± 11.81°, 38.30° ± 7.56°, and 44.93° ± 11.32°, respectively. All had a significantly lower PI than the historical control (P < .001, P < .001, P < .001, respectively). CONCLUSIONS: We conclude that patients presenting with FAI may have a lower PI than the general population. The clinical significance of a 5.7° difference in PI remains unknown. LEVEL OF EVIDENCE: Level III, retrospective comparative study.
PURPOSE: To investigate whether pelvic incidence (PI) in patients with symptomatic femoroacetabular impingement was different from that in a normal population. METHODS: Retrospective analysis of 30 consecutive female and 30 consecutive male patients with computed tomography scans who underwent hip arthroscopy for FAI. PI was measured using scout lateral radiographs. The center-edge angle (CEA), acetabular version, and α angle were also measured. Each patient was subcategorized as having a cam-type deformity (α angle >55°), a deep socket deformity (CEA >39°), and/or a retroverted acetabulum (acetabular anteversion <15°). Our group and subgroups were compared with a historical control group from a previously published study of 300 volunteers. Each group was compared using a Student t test. RESULTS: Our mean PI was 49.31° ± 12.34° (range, 28.4°-79.5°), less than the asymptomatic historical control (n = 300) with a mean PI of 55.0° ± 10.6° (range, 33°-82°) (P < .001). The subgroups for cam deformity, deep socket deformity, and acetabular retroversion have a mean PI of 48.89° ± 11.81°, 38.30° ± 7.56°, and 44.93° ± 11.32°, respectively. All had a significantly lower PI than the historical control (P < .001, P < .001, P < .001, respectively). CONCLUSIONS: We conclude that patients presenting with FAI may have a lower PI than the general population. The clinical significance of a 5.7° difference in PI remains unknown. LEVEL OF EVIDENCE: Level III, retrospective comparative study.
Authors: Roger Luo; Dena Barsoum; Humaira Ashraf; Jennifer Cheng; Nicole R Hurwitz; Campbell Y Goldsmith; Peter J Moley Journal: Arthroscopy Date: 2020-09-10 Impact factor: 4.772
Authors: Cort D Lawton; Bennet A Butler; Ryan S Selley; Kathryn A Barth; Earvin S Balderama; Tyler J Jenkins; Ujash Sheth; Vehniah K Tjong; Michael A Terry Journal: J Orthop Date: 2020-04-01