Abstract
Introduction
The aim of this study is to verify the intra-rater and inter-rater reliability of intra-operative kinematics by hand in TKA using a computer assisted image-free navigation system.
Material and Methods
Total knee arthroplasty (TKA) was performed on the knees of twelve (12) patients with knee navigation by one surgeon. Patients were divided into two groups: Group A included six knees that were operated on with assistant A (senior joint surgeon); and Group B included the other six knees that were operated on with assistant B (resident). For each knee, axial rotation was evaluated three times by the operator and the assistant using a navigation system at 30°, 60°, 90°, 120° passive flexions by hand. Intra-class correlation coefficients (ICC) were calculated for each evaluation to examine intra-rater and inter-rater reliability.
Results
As intra-rater reliability, ICC (1,1) of the operator were 0.965 (range: 0.951 to 0.978); assistant A were 0.949 (range: 0.898 to 0.974); and assistant B were 0.987 (range: 0.982 to 0.992). As inter-rater reliability, ICC (2,1) of the operator and assistant A were 0.947 (range: 0.937 to 0.975), while the operator and assistant B were 0.949 (range: 0.887 to 0.989). The results demonstrated almost perfect reliability (ICC>0.81) of the inter-examiner and intra-examiner in each knee flexion angle.
Conclusion
Intra-operative kinematic analysis by hand using a knee navigation system showed almost perfect reliability of not only the intra-examiner but also the inter-examiner. This result indicates that intra-operative kinematic analysis is useful information to be referred.
