title: Are leg length and hip offset comparable after hip resurfacing and cementless total hip arthroplasty?
abstract: BACKGROUND
  The purpose of this study was to determine if hip resurfacing arthroplasty (HRA) and cementless total hip arthroplasty (THA) were comparable in correcting leg length and hip offset in patients with primary osteoarthritis.
  
  
  METHODS
  A retrospective analysis was performed of 80 patients who underwent either HRA or cementless THA for primary osteoarthritis (40 in each group) between 2006 and 2008. Standardised anteroposterior radiographs taken pre-operatively and at one year following surgery were used to calculate the total offset and leg length in both hips.
  
  
  RESULTS
  At one year following surgery, no leg length discrepancy was identified in either group. A difference of 0.39 cm (p=0.046) remained between the mean total offset of the operated hip and the contralateral non-operated hip in the HRA group. No difference in offset was observed between the two hips after surgery in the THA group (p=0.875).
  
  
  CONCLUSIONS
  Leg length is restored by HRA and THA. A difference remains in offset after HRA although we attribute this to intentional medialisation of the acetabular cup.
authors.affiliation: Department of Orthopaedics, University College Hospital, London, UK. shelain.patel@doctors.org.uk
authors.forename: S
authors.initials: S
authors.lastname: Patel
authors.forename: R R
authors.initials: RR
authors.lastname: Thakrar
authors.forename: J
authors.initials: J
authors.lastname: Bhamra
authors.forename: F
authors.initials: F
authors.lastname: Hossain
authors.forename: M
authors.initials: M
authors.lastname: Tengrootenhuysen
authors.forename: F S
authors.initials: FS
authors.lastname: Haddad
mesh_terms: D000328:Adult; D000368:Aged; D019644:Arthroplasty, Replacement, Hip; D005260:Female; D005269:Femur / Q000473:pathology*; D006621:Hip Joint / Q000000981:diagnostic imaging / Q000473:pathology*; D006622:Hip Prosthesis; D006801:Humans; D007593:Joint Instability / Q000601:surgery; D007870:Leg Length Inequality / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011859:Radiography; D012189:Retrospective Studies