Sieker Jakob T, Rudert Maximilian, Steinert Andre F
Department of Orthopaedic Surgery, König-Ludwig-Haus, Julius-Maximilians-University Würzburg, Brettreichstr. 11, Würzburg, D-97074 Germany.
Springerplus. 2014 Jun 24;3:308. doi: 10.1186/2193-1801-3-308. eCollection 2014.
Premature implant loosening following total knee arthroplasty (TKA) can have several causes. In this article we report on a rare case of a 74 year old male patient suffering tibial component loosening 14 month after primary TKA. The patient did neither have any malignancies nor joint arthroplasty before. Upon clinical examination the range of motion in the diseased knee was painfully restricted to 80° of knee flexion, with the patient increasingly suffering sleeping and resting pain, and also at weight bearing. In standard radiographs, loosening of the TKA due to a large osteolysis at the tibial component was evident. Local computed tomography (CT) of the right knee revealed loosening of the tibial component due to a presumably malign bone tumor. For determination of the final diagnosis a representative biopsy of the tumor was taken by open surgery prior to the tumor resection. Histopathologic evaluation of the biopsy revealed a periprosthetic myxoid chondrosarcoma of the proximal tibia. Pre-operative staging examination included CT scans of lung and abdomen, as well as a bone scintigraphy which revealed no signs of tumor metastasis in the body. Surgical management comprised wide tumor resection and implantation of a hinged tumor knee arthroplasty with replacements of the distal femur and proximal tibia, as well as a patella tendon replacement using a synthetic ligament. Revision surgery was necessary twice due to impaired wound healing and critical soft tissue coverage, and treatment included a gastrocnemius muscle flap with skin mesh graft covering. Unfortunately long-term follow-up examinations could not be obtained, as the patient deceased due to an alveolitis during rehabilitation. In summary, the specifics of this rare case of aseptic TKA loosening, and the unusual circumstances of chondrosarcoma diagnosis and treatment are informative for those providing surgical treatment of similar cases.
全膝关节置换术（TKA）后早期植入物松动可能有多种原因。在本文中，我们报告了一例罕见病例，一名74岁男性患者在初次TKA术后14个月出现胫骨组件松动。该患者既往既无任何恶性肿瘤病史，也未接受过关节置换手术。临床检查发现，患侧膝关节活动范围因疼痛而受限，屈膝仅80°，患者睡眠和休息时疼痛加剧，负重时也疼痛。在标准X线片上，可见胫骨组件处因大量骨质溶解导致TKA松动。右膝局部计算机断层扫描（CT）显示，胫骨组件松动可能是由于恶性骨肿瘤所致。为明确最终诊断，在肿瘤切除术前通过开放手术对肿瘤进行了代表性活检。活检的组织病理学评估显示为胫骨近端假体周围黏液样软骨肉瘤。术前分期检查包括胸部和腹部CT扫描以及骨闪烁显像，结果显示体内无肿瘤转移迹象。手术治疗包括广泛的肿瘤切除以及植入带铰链的肿瘤膝关节置换物，同时置换股骨远端和胫骨近端，并使用合成韧带替代髌腱。由于伤口愈合不良和关键软组织覆盖不足，需要进行两次翻修手术，治疗包括采用带皮肤网状移植的腓肠肌肌瓣。不幸的是，由于患者在康复期间因肺泡炎死亡，未能获得长期随访检查结果。总之，这例罕见的无菌性TKA松动病例的具体情况以及软骨肉瘤诊断和治疗的特殊情况，对处理类似病例的外科医生具有参考价值。
