title: Clinical, functional, and radiographic outcomes following total knee arthroplasty with patient-specific instrumentation, computer-assisted surgery, and manual instrumentation: a short-term follow-up study.
abstract: OBJECTIVE
  The purpose of this study was to evaluate clinical, functional, and radiographic outcomes following total knee arthroplasty (TKA) performed with patient-specific instrumentation (PSI), computer-assisted surgery (CAS), and manual instruments at short-term follow-up.
  
  
  METHODS
  122 TKAs were performed by a single surgeon: 42 with PSI, 38 with CAS, and 40 with manual instrumentation. Preoperative, 1-month, and 6-month clinical and functional outcomes were measured using the Knee Society scoring system (knee score, function score, range of motion, and pain score). Improvements in clinical and functional outcomes from the preoperative to postoperative period were analyzed. Preoperative and postoperative radiographs were measured to evaluate limb and component alignment.
  
  
  RESULTS
  Preoperative, 1-month postoperative, and 6-month postoperative knee scores, function scores, range of motion, and pain scores were highest in the PSI group compared to CAS and manual instrumentation. At 6-month follow-up, PSI TKA was associated with a statistically significant improvement in functional score when compared to manual TKA. Otherwise, there were no statistically significant differences in improvements among PSI, CAS, and manual TKA groups.
  
  
  CONCLUSIONS
  The higher preoperative scores in the PSI group limits the ability to draw definitive conclusions from the raw postoperative scores, but analyzing the changes in scores revealed that PSI was associated with a statistically significant improvement in Knee Society Functional score at 6-month post-TKA as compared to CAS or manual TKA. This may be attributable to improvements in component rotation and positioning, improved component size accuracy, or other factors that are not discernible on plain radiograph.
authors: Department of Orthopaedic Surgery, Feinberg School of Medicine, Northwestern University, 676 North Saint Clair, Suite 1350, Chicago, IL, 60611, USA.
authors: Mark
authors: M
authors: Yaffe
authors: Michael
authors: M
authors: Luo
authors: Nitin
authors: N
authors: Goyal
authors: Philip
authors: P
authors: Chan
authors: Anay
authors: A
authors: Patel
authors: Max
authors: M
authors: Cayo
authors: S David
authors: SD
authors: Stulberg
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000295:instrumentation*; D004867:Equipment Design; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D056888:Patient Positioning; D016059:Range of Motion, Articular; D025321:Surgery, Computer-Assisted / Q000295:instrumentation*; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome