title: Preoperative pain and function profiles reflect consistent TKA patient selection among US surgeons.
abstract: BACKGROUND
  As the number of primary total knee arthroplasties (TKAs) performed in the United States increases, policymakers have questioned whether the indications and timing of TKA have evolved so that surgery is offered earlier.
  
  
  OBJECTIVE
  We analyzed data from a US national TKA cohort to evaluate variation in surgeon selection criteria for elective unilateral TKA based on preoperative patient-reported pain and function scores.
  
  
  METHODS
  Preoperative SF-36 (Physical Component Summary [PCS]/physical function) scores and Knee Injury and Osteoarthritis Outcome Score (KOOS) (pain, activities of daily living/function) of 4900 patients undergoing elective unilateral TKA enrolled in this national database of prospectively followed patients from 22 states were evaluated. The 25th, 50th, and 75th percentile pain and function scores for patients cared for in 24 orthopaedic offices with 20 or more patients in the database were compared to assess whether consistent preoperative criteria are used in selecting patients undergoing TKA across settings.
  
  
  RESULTS
  The preoperative global function (PCS median, 32.6; national norm, 50; SD, 10) and knee-specific function (KOOS median, 51.5; maximum score, 100; SD, 17) percentile scores represented substantial patient disability, because both values approached 2 SDs below ideal. Consistency in patients across 24 surgeon offices, and more than 100 surgeons, was noted because site-specific medians varied from the national median by less than the minimum clinically important change.
  
  
  CONCLUSIONS
  These data suggest that despite the rapidly growing use of TKA, surgeons in the participating sites use consistent patient criteria in scheduling TKA. Today's patients report significant pain and disability, supporting the need for TKA.
authors: Department of Orthopedics and Physical Rehabilitation, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, MA, 01655, USA, david.ayers@umassmemorial.org.
authors: David C
authors: DC
authors: Ayers
authors: Wenjun
authors: W
authors: Li
authors: Leslie
authors: L
authors: Harrold
authors: Jeroan
authors: J
authors: Allison
authors: Patricia D
authors: PD
authors: Franklin
mesh_terms: D000203:Activities of Daily Living; D018771:Arthralgia / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D019645:Arthroplasty, Replacement, Knee; D001696:Biomechanical Phenomena; D016208:Databases, Factual; D004185:Disability Evaluation; D017558:Elective Surgical Procedures; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology / Q000601:surgery*; D010147:Pain Measurement; D018579:Patient Selection; D010808:Physical Examination; D010818:Practice Patterns, Physicians'; D011237:Predictive Value of Tests; D013997:Time Factors; D061665:Time-to-Treatment; D014481:United States