Ligament balancer (LBS) in total knee arthroplasty - our experience.

Presenting Author – Umesh Nagare.
Presenting Author – Umesh Nagare. OBJECTIVE – To determine if a Ligament Balancer device (LBS, Exactech, USA) can be used effectively in TKA to restore flexion-extension balance and rotational and axial alignment. To determine if knees with more preoperative deformity would result in less accurate balance and alignment. METHODS – LBS was used to restore optimal stability and alignment during 88 consecutive total knee arthroplasties with a minimum of 6-week clinical and radiographic follow-up. Prospective data collection of 88 (38 bilateral, 12 unilateral) consecutive TKAs with a primary diagnosis of osteoarthritis or rheumatoid arthritis, performed by a single surgeon from January 2013 through November 2016, were analyzed. Knee Society scores (KSS) were collected preoperatively and postoperatively at a minimum of 6 weeks. All patients underwent primary TKA with a posterior-stabilized design (Optetrack, Exactech, USA). During surgery, LBS device was used with the knee in full extension and 90° flexion to measure the extension - flexion gap and angular asymmetry. Equal tension was applied in flexion and extension to achieve optimal flexion-extension balance. The surgical technique is followed as per LBS instrumentation. RESULTS – Mean flexion-extension symmetry was restored to within 1°. Of 88 knees, 6 had 3 mm of subjective laxity during component trialing and were associated with a preoperative deformity of 15°; 18 knees required femoral rotation of 5° and were associated with greater preoperative malalignment. Postoperative knee alignment, range of motion, Knee Society score, and lateral release rate were similar between the 2 groups. CONCLUSION – The use of a LBS device in total knee arthroplasty can achieve outcomes comparable to existing techniques with improved technical accuracy.