Gap balancing versus measured resection technique for total knee arthroplasty.
Multiple differing surgical techniques are currently utilized to perform total knee arthroplasty (TKA). We compared knee arthroplasties performed using either a measured resection or gap balancing technique to determine if either operative technique provides superior coronal plane stability as measured by assessment of the incidence and magnitude of femoral condylar lift-off. We performed 40 TKA using a measured resection technique (20 PCL-retaining and 20 PCL-substituting) and 20 PCL-substituting TKA were implanted using gap balancing. All subjects were analyzed fluoroscopically while performing a deep knee bend. The incidence of coronal instability (femoral condylar lift-off) was then determined using a 3-D model fitting technique. The incidence of lift-off greater than 0.75 mm was 80% (maximum, 2.9 mm) and 70% (maximum, 2.5 mm) for the PCL-retaining and substituting TKA groups performed using measured resection versus 35% (maximum, 0.88 mm) for the gap-balanced group. Lift-off greater than 1 mm occurred in 60% and 45% of the PCL-retaining and -substituting TKA using measured resection versus none in the gap-balanced group. Rotation of the femoral component using a gap balancing technique resulted in better coronal stability which we suggest will improve functional performance and reduce polyethylene wear.
Center for Musculoskeletal Research, University of Tennessee, Knoxville, TN, USA. kslutzky@co-ortho.com
Douglas A
DA
Dennis
Richard D
RD
Komistek
Raymond H
RH
Kim
Adrija
A
Sharma
D053587:Arthrometry, Articular; D019645:Arthroplasty, Replacement, Knee / Q000379:methods* / Q000534:rehabilitation; D001696:Biomechanical Phenomena; D005269:Femur / Q000601:surgery*; D005471:Fluoroscopy; D006801:Humans; D007593:Joint Instability / Q000517:prevention & control; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D016119:Posterior Cruciate Ligament / Q000503:physiopathology / Q000601:surgery*; D011183:Postoperative Complications / Q000000981:diagnostic imaging; D016059:Range of Motion, Articular; D020127:Recovery of Function; D013977:Tibia / Q000601:surgery*; D016474:Weight-Bearing