title: Total hip replacement through a posterior approach using a 22 mm diameter femoral head : the role of the transverse acetabular ligament and capsular repair in reducing the rate of dislocation.
abstract: Despite a lack of long-term follow-up, there is an increasing trend towards using femoral heads of large diameter in total hip replacement (THR), partly because of the perceived advantage of lower rates of dislocation. However, increasing the size of the femoral head is not the only way to reduce the rate of dislocation; optimal alignment of the components and repair of the posterior capsule could achieve a similar effect. In this prospective study of 512 cemented unilateral THRs (Male:Female 230:282) performed between 2004 and 2011, we aimed to determine the rate of dislocation in patients who received a 22 mm head on a 9/10 Morse taper through a posterior approach with capsular repair and using the transverse acetabular ligament (TAL) as a guide for the alignment of the acetabular component. The mean age of the patients at operation was 67 years (35 to 89). The mean follow-up was 2.8 years (0.5 to 6.6). Pre- and post-operative assessment included Oxford hip, Short Form-12 and modified University of California Los Angeles and Merle D'Aubigne scores. The angles of inclination and anteversion of the acetabular components were measured using radiological software. There were four dislocations (0.78%), all of which were anterior. In conclusion, THR with a 22 mm diameter head performed through a posterior approach with capsular repair and using the TAL as a guide for the alignment of the acetabular component was associated with a low rate of dislocation.
authors.affiliation: Wrightington Hospital, Centre for Hip Surgery, WN6 9EP, UK.
authors.forename: V
authors.initials: V
authors.lastname: Kumar
authors.affiliation: Barnsley Hospital NHS Foundation Trust, South Yorkshire, UK.
authors.forename: S
authors.initials: S
authors.lastname: Sharma
authors.affiliation: Wrightington Hospital, Centre for Hip Surgery, WN6 9EP, UK.
authors.forename: J
authors.initials: J
authors.lastname: James
authors.affiliation: Wrightington Hospital, Centre for Hip Surgery, WN6 9EP, UK.
authors.forename: J P
authors.initials: JP
authors.lastname: Hodgkinson
authors.affiliation: Wrightington Hospital, Centre for Hip Surgery, WN6 9EP, UK.
authors.forename: M V
authors.initials: MV
authors.lastname: Hemmady
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000295:instrumentation* / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006617:Hip Dislocation / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D011446:Prospective Studies; D016896:Treatment Outcome
keywords: Total hip replacement; Posterior approach; 22 mm femoral head; TAL; Dislocation