title: Accuracy of a hand-held surgical navigation system for tibial resection in total knee arthroplasty.
abstract: BACKGROUND
  Accuracy of total knee arthroplasty (TKA) implant placement and overall limb are important goals of TKA technique.
  
  
  METHODS
  The accuracy and ease of use of an accelerometer-based hand-held navigation system for tibial resection during TKA was examined in 90 patients. Preoperative goals for sagittal alignment, navigation system assembly time, resection time, and tourniquet time were evaluated. Coronal and sagittal alignment was measured postoperatively.
  
  
  RESULTS
  The average coronal tibial component alignment was 0.43° valgus; 6.7% of patients had tibial coronal alignment outside of ±3° varus/valgus. The difference between the intraoperative goal and radiographically measured posterior tibial slope was 0.5°. The average time to completion of the tibial cut was 4.6 minutes.
  
  
  CONCLUSIONS
  The accelerometer-based hand-held navigation system was accurate for tibial coronal and sagittal alignment during TKA, with no additional surgical time compared with conventional instrumentation.
authors.affiliation: Division of Orthopaedic Surgery, Scripps Clinic, La Jolla, CA, USA. Electronic address: bugbee.william@scrippshealth.org.
authors.forename: William D
authors.initials: WD
authors.lastname: Bugbee
authors.affiliation: Kaiser Permanente, San Diego, CA, USA.
authors.forename: Arash Y
authors.initials: AY
authors.lastname: Kermanshahi
authors.affiliation: Shiley Center for Orthopaedic Research & Education at Scripps Clinic, La Jolla, CA, USA.
authors.forename: Michelle M
authors.initials: MM
authors.lastname: Munro
authors.affiliation: Shiley Center for Orthopaedic Research & Education at Scripps Clinic, La Jolla, CA, USA.
authors.forename: Julie C
authors.initials: JC
authors.lastname: McCauley
authors.affiliation: Division of Orthopaedic Surgery, Scripps Clinic, La Jolla, CA, USA.
authors.forename: Steven N
authors.initials: SN
authors.lastname: Copp
mesh_terms: D061725:Accelerometry / Q000379:methods; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D017760:Bone Malalignment / Q000517:prevention & control; D034201:Computers, Handheld; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D061646:Operative Time; D011446:Prospective Studies; D025321:Surgery, Computer-Assisted / Q000295:instrumentation*; D013977:Tibia / Q000601:surgery*
keywords: Computer-assisted surgery; Navigation; Tibial alignment; Total knee arthroplasty