title: Computer-assisted gap balancing technique improves outcome in total knee arthroplasty, compared with conventional measured resection technique.
abstract: OBJECTIVE
  The objective of this prospective study was to compare the functional outcome of conventional measured resection technique and computer-assisted gap balancing technique in TKA.
  
  
  METHODS
  140 patients were randomized into two groups. The conventional measured resection technique without computer navigation was performed in Group 1 and the computer-assisted gap balancing technique in Group 2. Range of motion, clinical laxity assessment with KT-1000 arthrometer, postoperative radiological films and various functional knee scores were documented at 6 months and 2 years.
  
  
  RESULTS
  At 2 years, there were significantly more patients (five patients, 7%) in the Group 1 with flexion contractures of more than 5° (P = 0.05). There were significantly more outliers in the Group 1 (eight patients, 11%), who demonstrated anterior tibial translation >5 mm, than Group 2 (two patients, 3%) (P = 0.041). The total excursion at 20° was significantly higher in Group 1 at 6 months (P = 0.012) and after 2 years (P = 0.031). Group 2 was able to demonstrate significantly better limb alignment with fewer outliers (more than 3° varus/valgus) than Group 1. At 6-month follow-up, Group 2 demonstrated better outcomes in Function Score (P = 0.040) and Total Oxford Score (P = 0.031). At 2-year review, Group 2 had better outcome in the Total Oxford Score (0.030).
  
  
  CONCLUSIONS
  Computer-assisted gap balancing technique was able to achieve more precise soft tissue balance and restoration of limb alignment with better knee scores as compared to the conventional measured resection technique in total knee arthroplasty.
authors: Department of Orthopedic Surgery, Singapore General Hospital, Singapore, Singapore. pangheenee@hotmail.com
authors: Hee-Nee
authors: HN
authors: Pang
authors: Seng-Jin
authors: SJ
authors: Yeo
authors: Hwei-Chi
authors: HC
authors: Chong
authors: Pak-Lin
authors: PL
authors: Chin
authors: Johnny
authors: J
authors: Ong
authors: Ngai-Nung
authors: NN
authors: Lo
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects / Q000379:methods*; D001696:Biomechanical Phenomena; D017760:Bone Malalignment; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007593:Joint Instability / Q000517:prevention & control*; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods; D010865:Pilot Projects; D011183:Postoperative Complications / Q000175:diagnosis / Q000453:epidemiology; D011446:Prospective Studies; D011474:Prosthesis Design; D016059:Range of Motion, Articular / Q000502:physiology*; D012016:Reference Values; D018709:Statistics, Nonparametric; D025321:Surgery, Computer-Assisted / Q000009:adverse effects / Q000379:methods*; D016896:Treatment Outcome