title: The Sphygmomanometer Pain Test: A Simple Method for Identifying Patients at Risk of Excessive Pain after Total knee Arthroplasty.
abstract: BACKGROUND
  Despite the overall success of total knee arthroplasty (TKA), a relatively large proportion of patients remain dissatisfied with the outcome. We hypothesized that patients with a lower threshold for pain were more likely to have worse outcomes after TKA.
  
  
  METHODS
  Forty-eight consecutive patients with primary knee osteoarthritis graded a standardized painful stimulus caused by inflating a sphygmomanometer placed on the forearm, on a visual analog scale (VAS) scale before their TKA. We compared the VAS scores to patients' Knee Society scores and Knee Society function scores 2 years after TKA.
  
  
  RESULTS
  Patients with a severe VAS score (>74 mm) had significantly worse Knee Society scores compared to patients with mild (0-44 mm) and moderate (45-74 mm) VAS scores (55 ± 20.5 vs 81.5 ± 11.1 and 84.8 ± 13, respectively, P = .04) and worse Knee Society Function scores (34 ± 20.7 vs 75.2 ± 17.3 and 77 ± 17.4, respectively, P = .027) at 2 years after TKA.
  
  
  CONCLUSIONS
  Patients with a lower threshold for pain, as determined by a standardized painful stimulus, are more likely to have lower Knee Society pain and function scores after TKA.
authors.affiliation: Orthopedic Division, Assaf Harofeh Medical Center, Zerifin, Israel.
authors.forename: Yaron
authors.initials: Y
authors.lastname: Bar Ziv
authors.affiliation: Department of Orthopedic Surgery, Arthroplasty Division, Rabin Medical Center, Beilinson Campus, Petach Tikva, Israel.
authors.forename: Shai
authors.initials: S
authors.lastname: Shemesh
authors.affiliation: Orthopedic Division, Assaf Harofeh Medical Center, Zerifin, Israel.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Agar
authors.affiliation: Orthopedic Division, Assaf Harofeh Medical Center, Zerifin, Israel.
authors.forename: Shaike
authors.initials: S
authors.lastname: Benedict
authors.affiliation: Department of Orthopedic Surgery, Arthroplasty Division, Rabin Medical Center, Beilinson Campus, Petach Tikva, Israel.
authors.forename: Snir
authors.initials: S
authors.lastname: Heller
authors.affiliation: Department of Orthopedic Surgery, Arthroplasty Division, Rabin Medical Center, Beilinson Campus, Petach Tikva, Israel.
authors.forename: Yona
authors.initials: Y
authors.lastname: Kosashvili
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000601:surgery; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery; D010146:Pain / Q000209:etiology; D010147:Pain Measurement / Q000295:instrumentation / Q000379:methods*; D010149:Postoperative Pain / Q000209:etiology*; D011446:Prospective Studies; D019722:Sphygmomanometers; D016896:Treatment Outcome
keywords: catastrophizing pain; functional score; patient satisfaction; total knee arthroplasty; visual analog scale