Reliability of a navigation system for intra-operative evaluation of antero-posterior knee joint laxity
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Published on: May 5, 2023
Nicola Lopomo1, Simone Bignozzi, Sandra Martelli
1Istituto Ortopedico Rizzoli, Laboratorio di Biomeccanica, via di Barbiano, 1/10, Bologna BO 40136, Italy. n.lopomo@biomec.ior.it
Background:
The purpose of this study was to investigate about the reliability of measuring antero-posterior laxity within-subjects for in-vivo studies using a navigation system.
Methods:
The analysis was performed by enroling 60 patients undergoing anterior cruciate ligament ACL reconstruction, and assessing AP laxity during the Lachman and drawer tests.
Results:
For the navigation system standard deviation for intra-trial measures was 0.7 mm, thus the intra-trial repeatability coefficient was 2.2 mm; standard deviation for intra-trial measure was 1.2 mm, while the reference inter-trial repeatability coefficient between expert surgeons was 3.4 mm.
Conclusions:
In conclusion, this study suggests that KIN-Nav may represent a new method to measure and document AP laxity intra-operatively with improved accuracy and test the effect of surgical treatment in-vivo with higher sensitivity than in the past and this study quantify its reliability for within-subjects studies performed by a single expert surgeon.