CAJ | 학술논문

目的：探讨矢状位下股骨与假体力线匹配的关系，寻求假体早期松动原因，为膝关节肿瘤型假体安装和设计制造提供科学依据。方法取1例膝关节肿瘤型人工假体取出物建立3 D 数学模型并进行有限元分析，获取理论数据；结合86例患者术后冠状位、矢状位 X 线片股骨与假体偏倚角度，分析冠状位、矢状位股骨与假体力线偏倚对假体松动的影响；测量矢状位下股骨生理曲度，统计各年龄阶段股骨弧度。结果(1)假体髓内柄4个方向偏移角度对股骨髓腔松质骨形变的影响，偏倚3°时最大形变均值为(0.590±0.001) mm，偏倚6°时最大形变均值为(1.163±0.002) mm，偏倚角度＞3°，就超过了松质骨形变容许的上限0.58 mm，偏倚度数大小对髓腔骨质强迫形变的影响，差异有统计学意义(P＜0.05)；(2)86例术后2、5年，分别有78、67例获随访。冠状位术后2年偏倚角度＞3°者2例，未出现假体松动；术后5年偏倚角度＞3°者4例，占4.7%，2例出现无菌性松动，占2.3%；矢状位术后2年偏倚角度＞3°者8例，占9.3%，4例出现无菌性松动；术后5年偏倚角度＞3°且出现松动者13例(含术后2年出现无菌性松动的4例)，占15.1%。通过冠状位与矢状位偏倚角度对假体松动影响的构成比分析，差异有统计学意义(P＜0.01)，矢状位偏倚角度对假体松动影响明显；股骨矢状位生理弯曲远端弧度较近端弧度小。结论(1)肿瘤型假体髓内柄与髓腔力线偏倚角度超过3°，对股骨髓腔松质骨的应力就超过了松质骨变形容许的上限，矢状位股骨与假体力线对线不良是影响假体早期无菌性松动的重要力学因素。(2)矢状位股骨弧度存在差异，应根据个人情况选择适合的假体，有顺应股骨矢状位弧度的髓内针可能是今后肿瘤型假体置换术的最佳选择。
목적：탐토시상위하고골여가체력선필배적관계，심구가체조기송동원인，위슬관절종류형가체안장화설계제조제공과학의거。방법취1례슬관절종류형인공가체취출물건립3 D 수학모형병진행유한원분석，획취이론수거；결합86례환자술후관상위、시상위 X 선편고골여가체편의각도，분석관상위、시상위고골여가체력선편의대가체송동적영향；측량시상위하고골생리곡도，통계각년령계단고골호도。결과(1)가체수내병4개방향편이각도대고골수강송질골형변적영향，편의3°시최대형변균치위(0.590±0.001) mm，편의6°시최대형변균치위(1.163±0.002) mm，편의각도＞3°，취초과료송질골형변용허적상한0.58 mm，편의도수대소대수강골질강박형변적영향，차이유통계학의의(P＜0.05)；(2)86례술후2、5년，분별유78、67례획수방。관상위술후2년편의각도＞3°자2례，미출현가체송동；술후5년편의각도＞3°자4례，점4.7%，2례출현무균성송동，점2.3%；시상위술후2년편의각도＞3°자8례，점9.3%，4례출현무균성송동；술후5년편의각도＞3°차출현송동자13례(함술후2년출현무균성송동적4례)，점15.1%。통과관상위여시상위편의각도대가체송동영향적구성비분석，차이유통계학의의(P＜0.01)，시상위편의각도대가체송동영향명현；고골시상위생리만곡원단호도교근단호도소。결론(1)종류형가체수내병여수강력선편의각도초과3°，대고골수강송질골적응력취초과료송질골변형용허적상한，시상위고골여가체력선대선불량시영향가체조기무균성송동적중요역학인소。(2)시상위고골호도존재차이，응근거개인정황선택괄합적가체，유순응고골시상위호도적수내침가능시금후종류형가체치환술적최가선택。
Objective To investigate the matching relationship between femur and prosthesis alignment in sagittal plane, to seek causes for early prosthesis loosening and to provide a scientiifc proof for the installation, design and manufacture of clinical bone tumor prosthesis.Methods One knee tumor type prosthesis was collected from a patient to establish a 3 D mathematical model with a ifnite element analysis to obtain clinical data. The angle between femur and prosthesis of 86 patients on post-operative coronal and sagittal X-rays were analyzed to investigate the inlfuence of this bias on implant loosening. Physiological curvature of the femur in all age groups was measured. Results ( 1 ) Intramedullary stem bias angle in all four directions had inlfuence on cancellous bone deformation. At a bias of 3°, the maximum mean deformation value was ( 0.590±0.001 ) mm; at a bias of 6°, the maximum mean deformation value was ( 1.163 ± 0.002 ) mm; at a bias larger than 3°: the maximum value of cancellous bone deformation exceeded the limit ( 0.58 mm ). Statistical signiifcance was found in the effects of the bias angle on enforced deformation of intramedullary substantia ossea (P<0.05 ). ( 2 ) Out of 86 cases, 78 cases were followed up for 2 years and 67 cases for 5 years postoperatively. In coronal plane, at 2 years post-op 2 cases had a bias angle >3°, no loosening of the prosthesis was found; while at 5 years postoperatively, 4 cases ( 4.7% ) had coronal bias angle >3°, 2 of them ( 2.3% ) developed aseptic loosening. In sagittal plane, 8 cases ( 9.3% ) had bias angle >3°. At 2 years post-op, 4 of them developed aseptic loosening; while at 5 years post-op, 13 cases ( 15.1% ) had a bias angle >3° and loosening occurred in 13 cases, including 4 cases with aseptic loosening at 2 years postoperatively. Results of analyses on the constituent ratio of the effects of coronal and sagittal bias angles on the loosening of prosthesis showed statistical signiifcance (P<0.01 ). Sagittal bias angle had more signiifcant effects on prosthetic loosening. As for physiological curvature of the femur in sagittal plane, the distal arc was smaller than the proximal arc.Conclusions ( 1 ) When the bias angle of tumor type prosthetic stem is larger than 3°, the stress on the cancellous bone of the femoral canal exceeds the allowed deformation limit. Sagittal malalignment is an important factor in early aseptic loosening of the prosthesis. ( 2 ) Femoral curvature in sagittal plane varies between different patients. Individualized prosthesis that ifts the canal morphology should be applied.