title: Comparative demographics, ROM, and function after TKA in Chinese, Malays, and Indians.
abstract: BACKGROUND
  There is marked racial disparity in TKA use rates, demographics, and outcomes between white and Afro-Caribbean Americans. Comparative studies of ethnicity in patients undergoing TKAs have been mostly in American populations with an underrepresentation of Asian groups. It is unclear whether these disparities exist in Chinese, Malays, and Indians.
  
  
  OBJECTIVE
  We therefore determined whether (1) TKA use; (2) demographics and preoperative statuses; and (3) functional outcomes at 2 years after TKA differed among three ethnic groups, namely, Chinese, Malays, and Indians who underwent TKA.
  
  
  METHODS
  From our hospital joint registry we identified 5332 patients who had a primary TKA from 2004 to 2009. The cohort was stratified by race and subsequently compared for demographics, preoperative knee ROM, and deformity. At the second postoperative year we determined Knee Society scores, Oxford knee scores, and obtained SF-36 health questionnaires.
  
  
  RESULTS
  Six percent more Chinese patients underwent TKAs compared with Malays or Indians. Malays were operated on at a younger age with a higher body mass index. Chinese patients had more severe preoperative varus deformity. There were no major differences in joint ROM in all races. For Knee Society, Oxford knee, and SF-36 scores, Chinese patients had consistently higher preoperative and postoperative scores. Malays presented with the lowest preoperative scores but had the greatest improvement in scores at followup with postoperative scores similar to Chinese counterparts. Indians had the lowest postoperative scores and worst improvement of all
  
  
  CONCLUSIONS
  The variations in demographics, preoperative statuses, and subsequent postoperative outcomes between the races should be considered when comparing TKA outcome studies in Asian populations.
authors.affiliation: Orthopaedic Department, Singapore General Hospital, Outram Road, Singapore, 169608, Singapore. weiming.siow@gmail.com
authors.forename: Wei Ming
authors.initials: WM
authors.lastname: Siow
authors.forename: Pak Lin
authors.initials: PL
authors.lastname: Chin
authors.forename: Shi Lu
authors.initials: SL
authors.lastname: Chia
authors.forename: Ngai Nung
authors.initials: NN
authors.lastname: Lo
authors.forename: Seng Jin
authors.initials: SJ
authors.lastname: Yeo
mesh_terms: D000704:Analysis of Variance; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects; D044466:Asian People; D001696:Biomechanical Phenomena; D002681:China / Q000208:ethnology; D004185:Disability Evaluation; D054625:Healthcare Disparities / Q000208:ethnology*; D006801:Humans; D007194:India / Q000208:ethnology; D007719:Knee Joint / Q000503:physiopathology / Q000601:surgery*; D008296:Malaysia / Q000208:ethnology; D016059:Range of Motion, Articular; D020127:Recovery of Function; D012042:Registries; D012189:Retrospective Studies; D012846:Singapore / Q000453:epidemiology; D011795:Surveys and Questionnaires; D013997:Time Factors; D016896:Treatment Outcome