title: Degeneration of acetabular articular cartilage to bipolar hemiarthroplasty.
abstract: OBJECTIVE
  This study examined the rate of degeneration of acetabular cartilage by the bipolar head according to time, and also which clinical factors are related to the degeneration of acetabular cartilage.
  
  
  METHODS
  Among 192 patients (226 hip joints) who received bipolar hemiarthroplasty from August 1996 to August 2002, 61 patients (65 hip joints) were enrolled in this study, who were followed up for more than 2 years and showed no signs of dislocation, infection, or functional problems. A modified form of a computer assisted vector wear analysis program was used to measure the rate of degeneration of the acetabular cartilage. The factors that appeared to affect the rate of acetabular degeneration in the two groups was evaluated.
  
  
  RESULTS
  The average linear degenerative change in the acetabular cartilage and the volumetric degenerative change were 0.23 +/- 0.107mm/year and 114 +/- 47.2mm3/year, respectively. The result showed significant differences in activity and HHS between the 2 groups. The HHS showed a reverse relationship with the linear degeneration and volumetric degeneration, and the activity showed a correlation with the linear and volumetric degeneration.
  
  
  CONCLUSIONS
  The acetabular cartilage degenerates faster as the patient' activity increases, and slower with a higher HHS. When surgeons perform hip joint arthroplasty, it is strongly recommended that the life expectancy and the level of activity should be considered when deciding between a hemiarthroplasty and total hip arthroplasty.
authors.affiliation: Department of Orthopaedics, Inha University Hospital, Incheon, Korea. moon@inha.ac.kr
authors.forename: Kyoung Ho
authors.initials: KH
authors.lastname: Moon
authors.forename: Jun Soon
authors.initials: JS
authors.lastname: Kang
authors.forename: Tong Joo
authors.initials: TJ
authors.lastname: Lee
authors.forename: Sang Hyeop
authors.initials: SH
authors.lastname: Lee
authors.forename: Sung Wook
authors.initials: SW
authors.lastname: Choi
authors.forename: Man Hee
authors.initials: MH
authors.lastname: Won
mesh_terms: D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects*; D002358:Cartilage, Articular / Q000000981:diagnostic imaging*; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D011859:Radiography; D016896:Treatment Outcome