Weißenberger Manuel, Petersen Nils, Bölch Sebastian, Rak Dominik, Arnholdt Jörg, Rudert Maximilian, Holzapfel Boris Michael
Department of Orthopaedic Surgery, University of Wuerzburg, Koenig-Ludwig-Haus, Brettreichstr. 11, 97074, Wuerzburg, Germany.
Regenerative Medicine, Institute of Health and Biomedical Innovation, Queensland University of Technology, 60 Musk Ave, Kelvin Grove, 4059, Brisbane, Australia.
Oper Orthop Traumatol. 2020 Aug;32(4):273-283. doi: 10.1007/s00064-020-00656-w. Epub 2020 Mar 5.
Revision of unicompartmental knee arthroplasty (UKA) to total knee arthroplasty (TKA) with the in situ referencing technique aiming to preserve as much ligament function and epi-metaphyseal bone stock as possible.
Aseptic loosening, progression of osteoarthritis, periprosthetic fracture, periprosthetic infection, arthrofibrosis, polyethylene wear, malalignment, instability, femoro-tibial impingement.
Unexplained pain, localized or systemic active infection (anywhere).
Referencing for the tibia and the femur cuts is performed prior to implant removal. The tibial cutting jig and the initial tibial resection level is set in a way that the sawblade just fits under the tibial implant. In case too much bone needs to be removed to achieve flush implant sitting on both the medial and lateral tibia, a step cut needs to be performed to build up the medial defect with an augment. Prior to femoral component removal, rotational alignment is determined and intramedullary referencing for the distal femur osteotomy is performed. Level of constraint and additional tibial stem fixation is chosen according to the amount of bone resected and according to ligament stability.
Sterile dressings and elastic compression bandaging. No limitation of active/passive range of motion. Full weight-bearing or partial weight-bearing for 2 weeks postoperatively in the presence of bone or soft tissue defects.
Between 2008 and 2019, 84 patients underwent revision of unicompartmental knee arthroplasty. The mean follow-up was 64 months (range 3-132 months). Implant survival after revision of UKA to TKA was 92% (95% CI = 82-97%) at 5 years of follow-up and 86% (95% CI = 69-93%) at 10 years of follow-up. The mean Oxford knee score was 20.1 (6-39, SD ± 6.5) preoperatively and 30.2 (3-48, SD ± 11.3) postoperatively. The mean visual analogue scale was 6.9 (range 1-10, SD ± 1.8) preoperatively and 3.9 (range 0-9, SD ± 2.6) postoperatively.
采用原位参考技术将单髁膝关节置换术（UKA）翻修为全膝关节置换术（TKA），旨在尽可能保留更多的韧带功能和骨骺干骺端骨量。
无菌性松动、骨关节炎进展、假体周围骨折、假体周围感染、关节纤维性变、聚乙烯磨损、对线不良、不稳定、股骨-胫骨撞击。
不明原因疼痛、局部或全身活动性感染（任何部位）。
在取出植入物之前对胫骨和股骨截骨进行参考。胫骨截骨导向器和初始胫骨截骨水平的设置方式是使锯片刚好能置于胫骨植入物下方。如果需要去除过多骨质以使植入物在胫骨内外侧均能平齐就位，则需要进行阶梯状截骨，用骨增量器填充内侧缺损。在取出股骨组件之前，确定旋转对线并对股骨远端截骨进行髓内参考。根据切除的骨量和韧带稳定性选择约束程度和额外的胫骨柄固定方式。
无菌敷料和弹性加压包扎。主动/被动活动范围无限制。术后若存在骨或软组织缺损，2周内完全负重或部分负重。
2008年至2019年期间，84例患者接受了单髁膝关节置换术的翻修。平均随访64个月（范围3 - 132个月）。UKA翻修为TKA后的植入物5年随访生存率为92%（95%CI = 82 - 97%），10年随访生存率为86%（95%CI = 69 - 93%）。术前牛津膝关节评分平均为20.1（6 - 39，标准差±6.5），术后为30.2（3 - 48，标准差±11.3）。术前视觉模拟评分平均为6.9（范围1 - 10，标准差±1.8），术后为3.9（范围0 - 9，标准差±2.6）。
