Related Experiment Video
Updated: Jan 12, 2026
In Vitro Application of a Wireless Sensor in Flexion-Extension Gap Balance of Unicompartmental Knee Arthroplasty
Published on: May 5, 2023
Visual inspection provides precise intraoperative evaluation of tibial slope during unicompartmental knee
Harun Hawi1,2, Humam Hawi1, Emmanouil Liodakis2
1Orthopaedics University Hospital Jena, Campus Eisenberg, Friedrich-Schiller-University, Waldkliniken Eisenberg, Eisenberg, Thuriniga, Germany.
Purpose:
Accurate reconstruction of the posterior tibial slope (PTS) is essential for successful unicompartmental knee arthroplasty (UKA), yet intraoperative assessment remains challenging without advanced navigation tools. This study evaluated the accuracy of visual intraoperative assessment of PTS changes after tibial resection.
Methods:
Resection blocks from total knee arthroplasty (TKA) were processed to simulate UKA resections, providing a wide range of slope variations. PTS changes were measured radiographically and via optical scans of resection blocks from 55 patients with severe osteoarthritis. Three experienced surgeons visually estimated PTS changes, which were compared to reference measurements using intraclass correlation coefficients (ICCs), Pearson correlation, analysis of variance (ANOVA) and Tukey's honestly significant difference (HSD) tests.
Results:
Optical scan and radiographic measurements showed near-perfect agreement (ICC = 0.99). The mean deviation between surgeon estimates and radiographic measurements was 1.0° ± 0.7° (range 0°-3.0°). Examiner ICCs ranged from 0.88 to 0.96, and Pearson correlations were strong (0.77-0.87). ANOVA and HSD tests showed no significant differences between visual and reference measurements.
Conclusion:
Visual inspection by experienced surgeons provides a sufficiently accurate and reliable method for intraoperative assessment of PTS during UKA.
Level Of Evidence:
Level IV.
