First Clinical Medical College, Shandong University of Traditional Chinese Medicine, Jinan, China.
Department of Orthopaedics, The 960th Hospital of the PLA, Jinan, China.
Orthop Surg. 2022 Jun;14(6):1143-1151. doi: 10.1111/os.13297. Epub 2022 May 7.
To measure the full-length anteroposterior and lateral radiographs of lower limbs after the resection of a tumor in the distal femur and tumor-type knee prosthesis replacement and to analyze the factors leading to aseptic loosening of the prosthesis.
A total of 26 cases of tumor-type knee prosthesis replacement or revision due to the distal femoral tumor at our hospital from January 2007 to December 2019 were retrospectively analyzed. The patients were divided into the loosening and unloosening groups depending on whether aseptic loosening occurred after surgery. Full-length anteroposterior and lateral radiographs of lower limbs were used to measure bone resection length, length of prosthesis, distance of proximal apex of the medullary stem of the femoral prosthesis from the maximum arc of the anterior femoral arch, diameter of the medullary stem, etc. Data were analyzed, and the risk factors for aseptic loosening of the prosthesis were explored.
The ratio of the prosthetic length to the femoral length (63.72 ± 5.21) and the ratio of the femoral medullary stem diameter to the femoral diameter (26.03 ± 8.45) were smaller in the loosening group than in the unloosening group. The difference was statistically significant (p < 0.05). The distance between the apex of the medullary stem and the maximum arc of the anterior femoral arch was significantly shorter in the loosening group (3.47 ± 2.96) than in the unloosening group, and the difference was statistically significant (p < 0.05). The measurement of the lower limb alignment showed significant differences between the loosening and unloosening groups in terms of HKAA, mLDFA, and distance between the lower limb alignment and the center of the knee joint (p < 0.05). The logistic regression analysis showed that less than 30% ratio between the medullary stem diameter and the femoral diameter, less than 3 cm distance between the apex of the medullary stem and the maximum curvature of the anterior arch of the femur, distance between the lower limb alignment and the center of the knee joint, and presence of varus knee and valgus knee after the surgery were the risk factors for aseptic loosening of the prosthesis.
The diameter of the femoral medullary stem of the prosthesis, the apex position of the prosthetic stem, and the lower limb alignment are the risk factors for aseptic loosening of the prosthesis.
测量股骨远端肿瘤切除和肿瘤型膝关节假体置换术后下肢全长正侧位片，并分析导致假体无菌性松动的因素。
回顾性分析 2007 年 1 月至 2019 年 12 月我院因股骨远端肿瘤行肿瘤型膝关节假体置换或翻修的 26 例患者。根据术后是否发生无菌性松动，将患者分为松动组和未松动组。采用下肢全长正侧位片测量骨切除长度、假体长度、股骨假体髓腔干近端顶点距股骨前弓最大弧的距离、髓腔干直径等。分析数据，探讨假体无菌性松动的危险因素。
松动组假体长度与股骨长度比（63.72±5.21）和股骨髓腔干直径与股骨直径比（26.03±8.45）小于未松动组，差异有统计学意义（p<0.05）。松动组髓腔干顶点与股骨前弓最大弧的距离明显短于未松动组（3.47±2.96），差异有统计学意义（p<0.05）。下肢对线测量显示，松动组和未松动组在 HKAA、mLDFA 和下肢对线与膝关节中心的距离方面差异有统计学意义（p<0.05）。Logistic 回归分析显示，髓腔干直径与股骨直径比小于 30%、髓腔干顶点与股骨前弓最大曲率的距离小于 3cm、下肢对线与膝关节中心的距离、术后存在膝内翻和膝外翻是假体无菌性松动的危险因素。
假体股骨髓腔干直径、假体干顶点位置和下肢对线是假体无菌性松动的危险因素。
