슬관절 전치환술 치환물 삽입각에 대한 네비게이션을 이용한 측정치와 방사선학적 측정치 간의 상관관계 분석

Abstract

Purpose: To examine the correlation between the Navigation and radiographic measurements for the postoperative mechanical axis and component position in total knee arthroplasty. Materials and Methods: From December 2005 to May 2006, Navigation assisted MIS TKA was performed on 46 knees of 34 patients. After fixing the components, the mechanical axis (MA) of the lower extremity, femoral component position to the mechanical axis in the coronal plane (θ), tibial component position in the coronal (β) and sagittal (δ) planes was measured using the Navigation. Two observers measured the same angles using the postoperative follow-up radiographs. The measurements were compared and the correlation between the Navigation and radiographic measurement was analyzed. Results: The average Navigation measurements were valgus 0.02±1.09° for MA, varus 0.05±0.96° for θ, valgus 0.02±0.86° for β and 4.03±1.25o for δ. The mean radiographic measurements of observer 1 were valgus 0.71±3.73° for MA, valgus 1.14±1.72° for θ, valgus 0.90±1.47° for β and 4.51±2.03° for δ. Those of observer 2 were valgus 0.12±3.39o, valgus 0.16±1.96°, valgus 0.30±1.65° and 3.85±1.60°, respectively. Conclusion: The average of measurement for the component position showed a statistically significant difference in the MA (p=0.001), θ (p=0.000) and β (p=0.000) among three groups. There were a relatively high correlation between observer 1 and 2 for the radiographic measurements (r=0.67-0.96). However there was a very low correlation between the Navigation and radiographic measurements (r=0.10-0.39). Therefore, the possibility of a difference between the Navigation and radiographic measurement need to be considered when evaluating the component position.