title: Associations between preoperative functional status and functional outcomes of total joint replacement in the Dominican Republic.
abstract: OBJECTIVE
  In developed countries, the functional status scores of patients with poor preoperative scores undergoing total joint replacement (TJR) improve more following TJR than those for patients with better preoperative scores. However, those with better preoperative scores achieve the best postoperative functional outcomes. We determined whether similar associations exist in a developing country.
  
  
  METHODS
  Dominican patients undergoing total hip or knee replacement completed WOMAC and SF-36 surveys preoperatively and at 12-month follow-up. Patients were stratified into low-, medium- and high-scoring preoperative groups based on their preoperative WOMAC function scores. We examined the associations between the baseline functional status of these groups and two outcomes-improvement in functional status over 12 months and functional status at 12 months-using analysis of variance with multivariable linear regression.
  
  
  RESULTS
  Patients who scored the lowest preoperatively made the greatest gains in function and pain relief following their TJRs. However, there were no significant differences in pain or function at 12-month follow-up between patients who scored low and those who scored high on preoperative WOMAC and SF-36 surveys.
  
  
  CONCLUSIONS
  Patients with poor preoperative functional status had greater improvement but similar 12-month functional outcomes compared with patients who had a higher level of function before surgery. These results suggest that a policy of focusing scarce resources on patients with worse functional status in developing countries may optimize improvement following TJR without threatening functional outcome. Additional research is needed to confirm these findings in other developing countries and to understand why these associations vary between patients in the Dominican Republic and patients from developed countries.
authors.affiliation: Harvard Medical School, MS2, 107 Avenue Louis Pasteur, Vanderbilt Box 040, Boston, MA 02115, USA. kyle_dempsey@hms.harvard.edu.
authors.forename: Kyle E
authors.initials: KE
authors.lastname: Dempsey
authors.forename: Jamie E
authors.initials: JE
authors.lastname: Collins
authors.forename: Roya
authors.initials: R
authors.lastname: Ghazinouri
authors.forename: Luis
authors.initials: L
authors.lastname: Alcantara
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Thornhill
authors.forename: Jeffrey N
authors.initials: JN
authors.lastname: Katz
mesh_terms: D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000534:rehabilitation*; D019645:Arthroplasty, Replacement, Knee / Q000534:rehabilitation*; D003906:Developing Countries; D004293:Dominican Republic; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement / Q000379:methods; D057234:Preoperative Period; D020127:Recovery of Function; D012720:Severity of Illness Index; D016896:Treatment Outcome
keywords: improvement patterns; international; joint replacement; knee hip arthroplasty; medical mission