title: Postthrombotic syndrome after hip or knee arthroplasty: a cross-sectional study.
abstract: BACKGROUND
  Although the incidence of the postthrombotic syndrome (PTS) has been addressed in patients with symptomatic deep vein thrombosis (DVT), less information is available on the incidence in patients who develop asymptomatic DVT after major hip or knee arthroplasty.
  
  
  OBJECTIVE
  To determine whether symptomatic PTS occurs more frequently in patients who develop DVT after hip or knee arthroplasty than those who are free of DVT and to provide an estimate of the incidence of PTS in patients who had undergone major hip or knee arthroplasty and had proximal DVT, distal (calf) DVT, or no DVT.
  
  
  METHODS
  A cross-sectional study conducted at the Hamilton Health Sciences Corporation, Hamilton, Ontario, and the Academic Medical Centre, Amsterdam, the Netherlands.
  
  
  METHODS
  Two hundred fifty-five subjects who had undergone major hip or knee arthroplasty 2 to 7 years previously and had routine predischarge venography showing proximal DVT (n = 25), distal DVT (n = 66), or no DVT (n = 164) were enrolled from March 1993 through December 1998. The presence of symptomatic PTS confirmed by the presence of objectively confirmed venous valvular incompetence was ascertained.
  
  
  RESULTS
  The rates of PTS were low and not significantly different among the 3 subgroups: 1 (4.0%, 95% confidence interval [CI] = 0.1%-20.4%) of 25 patients with proximal DVT, 4 (6.1%, 95% CI = 1.7%-14.8%) of 66 patients with distal DVT, and 7 (4.3%, 95% CI = 1.7%-8.6%) of 164 patients with no DVT.
  
  
  CONCLUSIONS
  Symptomatic PTS is an uncommon complaint after major hip or knee arthroplasty. Patients who develop postoperative proximal or distal DVT and who receive 6 to 12 weeks of anticoagulant therapy are not predisposed to PTS.
authors.affiliation: Hamilton Civic Hospitals Research Centre, McMaster University, Ontario, Canada.
authors.forename: J S
authors.initials: JS
authors.lastname: Ginsberg
authors.forename: F
authors.initials: F
authors.lastname: Turkstra
authors.forename: H R
authors.initials: HR
authors.lastname: Buller
authors.forename: B
authors.initials: B
authors.lastname: MacKinnon
authors.forename: D
authors.initials: D
authors.lastname: Magier
authors.forename: J
authors.initials: J
authors.lastname: Hirsh
mesh_terms: D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects*; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D009864:Ontario / Q000453:epidemiology; D010991:Plethysmography; D011186:Postphlebitic Syndrome / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*; D020246:Venous Thrombosis / Q000150:complications* / Q000175:diagnosis / Q000209:etiology*