Rajgopal Ashok, Panda Inayat, Yadav Sidharth, Wakde Om
Department of Orthopaedics, Fortis Bone and Joint Institute, Fortis Escorts, New Delhi, India.
J Knee Surg. 2019 Sep;32(9):833-840. doi: 10.1055/s-0038-1669789. Epub 2018 Sep 6.
Severe bone loss in distal femur has traditionally been managed with bulk cementing, bone graft, metal augments, trabecular metal cones, and mega prosthesis. The authors present an alternative method using a stacked configuration of two tantalum cones to manage severe distal femoral bone loss. This study aims to evaluate the mid-term outcomes and possible complications in patients treated with this novel technique. We retrospectively analyzed the prospectively maintained records of 16 knees (in 16 patients) presenting with severe distal femoral bone deficiency due to septic loosening (5), giant cell tumor (GCT; 4), periprosthetic fracture (3), aseptic loosening (3), and distal femoral comminuted fracture with severe osteoarthritis (1). A standard medial parapatellar approach was taken in all our cases followed by preparation of distal femoral bone defect and use of two bridging tantalum trabecular metal cones to fill the defect, followed by implantation of rotating hinge knee prosthesis. At an average follow-up of 57 months (4.75 years), the average Knee Society Score was 74.56 (64-87) and the mean range of motion was 97.8 (70-120) degrees. Radiologically, all 16 knees showed good osteointegration with no evidence of progressive radiolucency or loosening. Complications included two patients with superficial infection (healed with antibiotics), and one with recurrence of GCT requiring tumor megaprosthesis reconstruction. The authors concluded that the stacked configuration of cones provides additional coverage and stability with good osteointegration and found it to be particularly useful in distal femoral GCTs and fracture situations. They recommend the use of stacked cones in selected cases of severe distal femoral deficiency.
传统上，股骨远端的严重骨缺损采用骨水泥填充、骨移植、金属增强物、小梁金属锥体和大型假体进行处理。本文作者提出了一种使用两个钽锥体堆叠结构来处理严重股骨远端骨缺损的替代方法。本研究旨在评估采用这种新技术治疗的患者的中期疗效和可能出现的并发症。我们回顾性分析了16例患者（16个膝关节）的前瞻性记录资料，这些患者因感染性松动（5例）、骨巨细胞瘤（GCT；4例）、假体周围骨折（3例）、无菌性松动（3例）以及伴有严重骨关节炎的股骨远端粉碎性骨折（1例）而出现严重的股骨远端骨缺损。所有病例均采用标准的髌旁内侧入路，随后准备股骨远端骨缺损，使用两个桥接钽小梁金属锥体填充缺损，然后植入旋转铰链膝关节假体。平均随访57个月（4.75年）时，膝关节协会评分平均为74.56（64 - 87），平均活动范围为97.8（70 - 120）度。影像学检查显示所有这16个膝关节均有良好的骨整合，没有进行性透亮区或松动的迹象。并发症包括2例浅表感染患者（经抗生素治疗痊愈），以及1例骨巨细胞瘤复发患者，需要进行肿瘤大型假体重建。作者得出结论，锥体的堆叠结构提供了额外的覆盖范围和稳定性，具有良好的骨整合，并且发现其在股骨远端骨巨细胞瘤和骨折情况中特别有用。他们建议在选定的严重股骨远端缺损病例中使用堆叠锥体。
