Abstract：
BACKGROUND: Giant cell tumor of bone (GCTB) is an intermediate tumor commonly arising from the epiphysis of the distal femur and proximal tibia. Standard GCTB treatment is joint-preserving surgery performed using thorough curettage and the filling of the cavity with allo-, auto-, polymethyl methacrylate (PMMA), or synthetic bone graft. Calcium phosphate cement (CPC) is an artificial bone substitute, which has the benefit of being able to adjust defects, consequently inducing immediate mechanical strength, and promoting biological healing. Secondary osteoarthritis may occur following GCTB treatment and may need additional surgery if severe. However, details regarding surgery for secondary osteoarthritis have not been fully elucidated. There are no reports on the use of total knee arthroplasty (TKA) for the treatment of secondary osteoarthritis following CPC packing. The insertion of an alignment rod is a standard procedure in TKA; however, it was difficult to perform in this case due to CPC. Therefore, we used a computed tomography (CT)-free navigation system to assist the distal femur cut. This study presents a knee joint secondary osteoarthritis case following CPC packing for GCTB curettage that was treated with standard TKA.
METHODS: A 67-year-old Japanese woman, who was previously diagnosed with left distal femur GCTB and was treated by curettage and CPC packing 7 years ago, complained of severe knee pain. Left knee joint plain radiography revealed Kellgren and Lawrence (K-L) grade 4 osteoarthritis without evidence of tumor recurrence. Therefore, she was scheduled for TKA. There are no reports on the cutting of a femoral condyle surface with massive CPC with accurate alignment. Because it is difficult to insert the alignment rod intramedullary and cut the femoral condyle with CPC, we planned CT-free navigation-guided surgery for accurate bone cutting using an oscillating tip saw system to prevent CPC cracks. We performed standard TKA without complications, as planned. Postoperative X-ray showed normal alignment. Knee Society Knee Score (KSKS) and Knee Society Function Score (KSFS) ameliorated from 27 and 29 to 64 and 68, respectively The patient can walk without a cane postoperatively.
CONCLUSIONS: There was no report about the surface TKA guided by CT-free navigation after primary GCT surgery with CPC. We believe that this case report will help in planning salvage surgery for secondary osteoarthritis after CPC packing.
METHODS: A 67-year-old Japanese woman, who was previously diagnosed with left distal femur GCTB and was treated by curettage and CPC packing 7 years ago, complained of severe knee pain. Left knee joint plain radiography revealed Kellgren and Lawrence (K-L) grade 4 osteoarthritis without evidence of tumor recurrence. Therefore, she was scheduled for TKA. There are no reports on the cutting of a femoral condyle surface with massive CPC with accurate alignment. Because it is difficult to insert the alignment rod intramedullary and cut the femoral condyle with CPC, we planned CT-free navigation-guided surgery for accurate bone cutting using an oscillating tip saw system to prevent CPC cracks. We performed standard TKA without complications, as planned. Postoperative X-ray showed normal alignment. Knee Society Knee Score (KSKS) and Knee Society Function Score (KSFS) ameliorated from 27 and 29 to 64 and 68, respectively The patient can walk without a cane postoperatively.
CONCLUSIONS: There was no report about the surface TKA guided by CT-free navigation after primary GCT surgery with CPC. We believe that this case report will help in planning salvage surgery for secondary osteoarthritis after CPC packing.
摘要：
背景：骨巨细胞瘤（GCTB）是一种中间肿瘤，通常由股骨远端和胫骨近端的骨phy形成。标准的GCTB治疗是使用彻底刮宫术和用同种异体填充腔进行的关节保留手术，auto-,聚甲基丙烯酸甲酯(PMMA),或者合成骨移植.磷酸钙骨水泥(CPC)是一种人工骨替代物,它的好处是能够调整缺陷，因此诱导立即的机械强度，促进生物愈合。继发性骨关节炎可能在GCTB治疗后发生，如果严重，可能需要额外的手术。然而,关于继发性骨关节炎手术的细节尚未完全阐明.没有关于使用全膝关节置换术（TKA）治疗CPC填塞后继发性骨关节炎的报道。对准杆的插入是TKA中的标准程序；然而，由于CPC，在这种情况下很难执行。因此,我们使用无计算机断层扫描（CT）的导航系统来辅助股骨远端切割。这项研究提出了用标准TKA治疗的CPC填塞GCTB刮除后的膝关节继发性骨关节炎病例。
方法：一位67岁的日本女性，先前被诊断为左股骨远端GCTB，并在7年前接受了刮宫和CPC包装治疗，抱怨严重的膝盖疼痛。左膝关节平片显示Kellgren和Lawrence（K-L）4级骨关节炎，没有肿瘤复发的证据。因此,她被安排去TKA.没有关于用大量CPC精确对准切割股骨髁表面的报道。因为很难将对准杆插入髓内并用CPC切割股骨髁，我们计划使用摆动刀头锯系统进行无CT导航引导手术，以防止CPC裂缝。我们进行标准TKA无并发症,按计划进行。术后X线显示对准正常。膝关节社会膝关节评分（KSKS）和膝关节社会功能评分（KSFS）分别从27和29改善到64和68。患者术后无需拐杖即可行走。
结论：没有关于CPC初次GCT手术后无CT导航引导的表面TKA的报道。我们认为，该病例报告将有助于计划CPC包装后继发性骨关节炎的抢救手术。
方法：一位67岁的日本女性，先前被诊断为左股骨远端GCTB，并在7年前接受了刮宫和CPC包装治疗，抱怨严重的膝盖疼痛。左膝关节平片显示Kellgren和Lawrence（K-L）4级骨关节炎，没有肿瘤复发的证据。因此,她被安排去TKA.没有关于用大量CPC精确对准切割股骨髁表面的报道。因为很难将对准杆插入髓内并用CPC切割股骨髁，我们计划使用摆动刀头锯系统进行无CT导航引导手术，以防止CPC裂缝。我们进行标准TKA无并发症,按计划进行。术后X线显示对准正常。膝关节社会膝关节评分（KSKS）和膝关节社会功能评分（KSFS）分别从27和29改善到64和68。患者术后无需拐杖即可行走。
结论：没有关于CPC初次GCT手术后无CT导航引导的表面TKA的报道。我们认为，该病例报告将有助于计划CPC包装后继发性骨关节炎的抢救手术。
