title: The indirect cost of Patient-Specific Instruments.
abstract: OBJECTIVE
  To calculate the indirect costs of Patient Specific Instruments (PSI) based on an opportunity cost, cost of efforts and a supply chain cost model to compare PSI for value with conventional total knee arthroplasty (TKA).
  
  
  METHODS
  In 81 patients the total (direct+indirect) cost of PSI-assisted TKA was compared with conventional TKA. Surgical times and coronal mechanical alignment were measured to evaluate the effectiveness of the PSI system.
  
  
  RESULTS
  Indirect costs (459 euro) make up 40% of the total cost that can run up to 1142 euro for a patient operated with PSI guides. No difference in surgical times or coronal alignment was observed in between both groups.
  
  
  CONCLUSIONS
  Considering the total cost of PSI no value was found for the use of PSI in primary TKA as measured by surgical times or for obtaining a neutral mechanical axis in the coronal plane.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Thienpont
authors.forename: Frederic
authors.initials: F
authors.lastname: Paternostre
authors.forename: Charles
authors.initials: C
authors.lastname: Van Wymeersch
mesh_terms: D019645:Arthroplasty, Replacement, Knee / Q000191:economics / Q000295:instrumentation*; D017076:Computer-Aided Design; D003365:Costs and Cost Analysis; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007720:Knee Prosthesis / Q000191:economics*; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery; D066230:Patient-Specific Modeling / Q000191:economics*; D011474:Prosthesis Design; D012189:Retrospective Studies; D025321:Surgery, Computer-Assisted / Q000191:economics* / Q000295:instrumentation