title: Development of a scale to assess performance following primary total knee arthroplasty.
abstract: BACKGROUND
  Quantitative assessment of postsurgical knee motion provides sensitive measurements, but results are technical and may not be meaningful to patients. Although several knee-specific instruments exist, no patient-reported outcome (PRO) measure correlates function with improved stability, motion, satisfaction, and confidence.
  
  
  OBJECTIVE
  To address both the above limitations by developing a PRO measure to assess the phenomenon of a "normal" knee after primary total knee arthroplasty (TKA).
  
  
  METHODS
  A draft conceptual model linking the impact of clinical mechanics to hypothesized functional outcomes was generated after a literature review of available assessment tools. Participants aged 18 to 80 years having undergone TKA within the past 10 to 18 months were identified and screened by clinical sites to participate in phase 1 focus groups or phase 2 in-depth interviews. Participants were asked to describe their TKA experiences, including how their knee feels now, followed by cognitive debriefing of Patient's Knee Implant Performance (PKIP) draft items.
  
  
  RESULTS
  Phase 1 results indicated that concepts of confidence, stability, and satisfaction in patients' replacement knee when performing certain activities were distinct and important in the patients' assessment of their TKA. Phase 2 efforts yielded a final version of the PKIP measure containing nine items assessing the broader concepts of stability, confidence, and satisfaction in association with activities. Presurgical and postsurgical versions of the measure were created.
  
  
  CONCLUSIONS
  Results of this qualitative study support use of the PKIP as a complementary PRO measure to assess performance after primary TKA. Psychometric evaluation of the PKIP is planned.
authors: RTI Health Solutions, Research Triangle Park, NC.
authors: Sandy
authors: S
authors: Lewis
authors: RTI Health Solutions, Research Triangle Park, NC.
authors: Mark
authors: M
authors: Price
authors: DePuy Synthes Joint Reconstruction, Inc. Warsaw, IN.
authors: Kimberly A
authors: KA
authors: Dwyer
authors: Belfast Trust, Musgrave Park Hospital, Belfast, Northern Ireland, UK.
authors: Seamus
authors: S
authors: O'Brien
authors: Heekin Orthopedic Specialists, Jacksonville, FL.
authors: R David
authors: RD
authors: Heekin
authors: Fremantle Hospital, Crawley, Australia.
authors: Piers J
authors: PJ
authors: Yates
authors: Belfast Trust, Musgrave Park Hospital, Belfast, Northern Ireland, UK.
authors: David
authors: D
authors: Beverland
authors: RTI Health Solutions, Ann Arbor, MI. Electronic address: mmordin@rti.org.
authors: Margaret
authors: M
authors: Mordin
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000523:psychology*; D004185:Disability Evaluation; D005260:Female; D017144:Focus Groups; D006801:Humans; D007407:Interviews as Topic; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D017063:Outcome Assessment, Health Care; D010147:Pain Measurement; D017060:Patient Satisfaction; D036301:Qualitative Research; D016059:Range of Motion, Articular / Q000502:physiology*; D020127:Recovery of Function; D057566:Self Report; D011795:Surveys and Questionnaires
keywords: arthroplasty; knee; qualitative research; questionnaires; replacement; self-report