Posterior capsular release is a biomechanically safe procedure to perform in total knee arthroplasty

• Published in: Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA sports traumatology, arthroscopy : official journal of the ESSKA, 2019-05, Vol.27 (5), p.1587-1594
• Main Authors: Athwal, K. K., Milner, P. E., Bellier, G., Amis, Andrew A.
• Format: Article
• Language: English
• Subjects: Arthroplasty (knee); Axial loads; Biocompatibility; Biomechanics; Biomedical materials; Cadavers; Control stability; Cutting; Femur; Joint surgery; Knee; Medical personnel; Medicine; Medicine & Public Health; Orthopedics; Surgery; Surgical implants
• ISSN: 0942-2056; 1433-7347
• DOI: 10.1007/s00167-018-5094-0

Purpose Surgeons may attempt to strip the posterior capsule from its femoral attachment to overcome flexion contracture in total knee arthroplasty (TKA); however, it is unclear if this impacts anterior–posterior (AP) laxity of the implanted knee. The aim of the study was to investigate the effect of posterior capsular release on AP laxity in TKA, and compare this to the restraint from the posterior cruciate ligament (PCL). Methods Eight cadaveric knees were mounted in a six degree of freedom testing rig and tested at 0°, 30°, 60° and 90° flexion with ± 150 N AP force, with and without a 710 N axial compressive load. After the native knee was tested, a deep dished cruciate-retaining TKA was implanted and the tests were repeated. The PCL was then cut, followed by releasing the posterior capsule using a curved osteotome. Results With 0 N axial load applied, cutting the PCL as well as releasing the posterior capsule significantly increased posterior laxity compared to the native knee at all flexion angles, and CR TKA states at 30°, 60° and 90° ( p