2021 ISAKOS Biennial Congress Paper
Effect Of Femoral And Acetabular Version On Outcomes Following Hip Arthroscopy: A Systematic Review And Meta-Analysis
Casey Wang, MD, Hamilton, ON CANADA
Dan Cohen, MD, Hamilton CANADA
Jeffrey Kay, MD, Toronto, ON CANADA
Mahmoud Almasri, MD, FRCSC, Cincinnati, Ohio UNITED STATES
Nicole Simunovic, MSc, Hamilton, ON CANADA
Carlomagno Cardenas-Nylander, MD, Barcelona SPAIN
Anil S. Ranawat, MD, New York, NY UNITED STATES
Olufemi R. Ayeni, MD, PhD, MSc, FRCSC, Hamilton, ON CANADA
McMaster University, Hamilton, Ontario, CANADA
FDA Status Not Applicable
Summary
This systematic review of the literature indicates that while acetabular or femoral retroversion yield similar outcomes following hip arthroscopy to patients with normal acetabular or femoral version, patients with excess femoral anteversion had mixed functional outcomes postoperatively and higher rates of conversion to total hip arthroplasty (THA) at final follow-up.
Abstract
Purpose
The purpose of this systematic review was to evaluate the impact of femoral and acetabular version on clinical outcomes following arthroscopic hip surgery.
Methods
Three databases (MEDLINE, EMBASE, and PubMed) were searched by two reviewers independently on December 15, 2020. Titles, abstracts, and full-text articles were screened in duplicate. Studies examining femoral and acetabular version in primary hip arthroscopy with patient-reported outcomes were included. The Methodological Index For Non-Randomized Studies (MINORS) instrument was used for quality assessment of studies. A random effects model was used to pool comparative post-operative outcomes between groups.
Results
Overall, 14 studies met the inclusion criteria and comprised 1754 patients (1763 hips), 1062 femora, and 701 acetabula, with a mean age of 29.8 (range 14-74.7) and mean follow-up of 40.4 months (range 4.8-113.4). Femoral version was measured on cross-sectional imaging in all studies investigating femur-based abnormalities. The most common lower bound defined for normal femoral version was 5 degrees, while the most common upper bound was 20 degrees. Patients with femoral retroversion had no significant difference in postoperative outcomes compared to those with normal version with mean differences (95% CI, p-value) in post-operative mHHS, HOS-SSS, VAS and NAHS scores of 1.68 (-3.19 to 6.54, p=0.50), 4.03 (-3.29 to 11.35, p=0.18), 0.05 (-0.42 to 0.53, p=0.82), and 3.38 (-1.96 to 8.71, p=0.22), respectively. In the high femoral anteversion groups, the mean difference (95% CI, p-value) in post-operative mHHS score was significantly lower than in the normal version groups [–4.28 (-8.20 to -0.37, p=0.03)] while there was no significant difference in the mean difference in post-operative HOS-SSS [-7.82 (-21.98 to 6.34, p=0.08)]. Of note, conversion rate to THA at final follow-up was 7.7% (n=11) in patients with femoral retroversion, and 13.6% (n=6) in patients with high femoral anteversion. In the acetabular retroversion group, there were no significant differences noted postoperatively for the VAS, mHHS, and HOS-SSS scores compared the groups with normal acetabular version.
Conclusion
While the definition of normal version of the hip varied within the literature, arthroscopic surgery in patients with femoral or acetabular retroversion generally resulted in equivalent functional and radiographic outcomes when compared to patients with normal version. However, patients with retroverted femora also had important conversion rates to total hip arthroplasty (THA). Postoperative functional outcomes in patients with high femoral anteversion compared to patients with normal femoral version were largely inconclusive, yet rates of conversion to THA were even higher in excessively anteverted femora. Further prospective studies would be useful in identifying precise surgical indications for safe arthroscopic surgery in patients with version abnormalities of the femur and acetabulum, particularly those with femoral anteversion.