title: Are patient-specific cutting blocks cost-effective for total knee arthroplasty?
abstract: BACKGROUND
  Using patient-specific cutting blocks for TKA increases the cost to the hospital for these procedures, but it has been proposed they may reduce operative times and improve implant alignment, which could reduce the need for revision surgery.
  
  
  OBJECTIVE
  We compared TKAs performed with patient-specific cutting blocks with those performed with traditional instrumentation to determine whether there was improved operating room time management and component coronal alignment to support use of this technology.
  
  
  METHODS
  We retrospectively reviewed 57 patients undergoing primary TKAs using patient-specific custom cutting blocks for osteoarthritis and compared them with 57 matched patients undergoing TKAs with traditional instrumentation during the same period (January 2009 to September 2010). At baseline, the groups were comparable with respect to age, sex, and BMI. We collected data on operative time (total in-room time and tourniquet time) and measured component alignment on plain radiographs.
  
  
  RESULTS
  On average, TKAs performed with patient-specific instrumentation had similar tourniquet times (61.0 versus 56.2 minutes) but patients were in the operating room 12.1 minutes less (137.2 versus 125.1 minutes) than those in the standard instrumentation group. We observed no difference in the femorotibial angle in the coronal plane between the two groups.
  
  
  CONCLUSIONS
  Patient-specific instrumentation for TKA shows slight improvement in operating room time management but none in component alignment postoperatively. Therefore, routine use of this new technology may not be cost-effective in its current form.
  
  
  METHODS
  Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.
authors.affiliation: Department of Orthopaedic Surgery, Washington University School of Medicine, One Barnes-Jewish Hospital Plaza, 11300 West Pavilion, Campus Box 8233, St Louis, MO 63110, USA. nunleyr@wustl.edu
authors.forename: Ryan M
authors.initials: RM
authors.lastname: Nunley
authors.forename: Bradley S
authors.initials: BS
authors.lastname: Ellison
authors.forename: Erin L
authors.initials: EL
authors.lastname: Ruh
authors.forename: Brandon M
authors.initials: BM
authors.lastname: Williams
authors.forename: Keith
authors.initials: K
authors.lastname: Foreman
authors.forename: Adrienne D
authors.initials: AD
authors.lastname: Ford
authors.forename: Robert L
authors.initials: RL
authors.lastname: Barrack
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000191:economics* / Q000295:instrumentation* / Q000379:methods; D017760:Bone Malalignment / Q000517:prevention & control; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D007719:Knee Joint / Q000000981:diagnostic imaging; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D009873:Operating Rooms / Q000191:economics / Q000458:organization & administration; D020370:Osteoarthritis, Knee / Q000601:surgery*; D017755:Prosthesis Fitting; D012189:Retrospective Studies; D025321:Surgery, Computer-Assisted / Q000295:instrumentation* / Q000379:methods; D017748:Time Management; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome