Acetabular Abduction and Dislocations in Direct Anterior vs Posterior Total Hip Arthroplasty: A Retrospective, Matched Cohort Study

• Published in: The Journal of arthroplasty Vol. 31; no. 10; pp. 2299 - 2302
• Main Authors: Tripuraneni, Krishna R., MD, Munson, Natalie R., MPH, MBA, Archibeck, Michael J., MD, Carothers, Joshua T., MD
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.10.2016
• Subjects: Acetabulum - surgery; Adult; Aged; arthroplasty; Arthroplasty, Replacement, Hip - adverse effects; Arthroplasty, Replacement, Hip - methods; direct anterior approach; Female; Fluoroscopy - methods; hip; hip dislocation; Hip Joint - physiology; Hip Prosthesis; Humans; Joint Dislocations - etiology; Male; Middle Aged; Orthopedics; Patient Positioning; Retrospective Studies; supine position; retrospective studies; supine position; direct anterior approach; arthroplasty; hip; hip dislocation
• ISSN: 0883-5403; 1532-8406
• DOI: 10.1016/j.arth.2016.03.008

Abstract Background There is purported improvement in component positioning and hip stability with the use of direct anterior approach (DAA) total hip arthroplasty (THA). We sought to determine if there is a difference in acetabular component position or dislocation frequency between DAA and posterior THA. Methods One arthroplasty fellowship-trained surgeon introduced DAA THA into his practice. From the initiation of DAA in 4/2012-8/2015, this comparative series resulted in 66 DAA THAs. A matched cohort (age, gender, body mass index [BMI], and comorbidities) was then created for posterior THA, 66 hips. DAA THA used fluoroscopy with anterior capsular excision; posterior group used no image guidance and had capsular repair. Posterior group BMI was 27.8 and DAA group BMI was 27.6 ( P  = .36). Minimum 3-month follow-up occurred in both groups. Results Average acetabular abduction angle in the posterior group was 41.9° (range, 32°-60°; standard deviation [sdev], 6.24) and DAA group 43.8° (range, 30°-62°; sdev 6.9), P  = .12. The percentage of outliers (outside Lewinnek safe zone, 30°-50°) was 9.1% (6 of 66) in posterior group and 13.6% (9 of 66) in DAA group. There were 2 anterior dislocations in the DAA THA group and 1 anterior dislocation in the posterior THA group, resulting in P  = .56. The DAA dislocation frequency in this group was overall higher at 3.0% (2 of 66) compared with the matched posterior (1.5%, 1 of 66) and unmatched posterior larger series (.8%, 3 of 360). Conclusion We demonstrated no observable difference in hip stability or acetabular abduction. This study provides realistic outcomes for surgeons implementing DAA THA into their practice.