From the Adult Reconstruction and Joint Replacement Service (Dr. Sculco), the Department of Orthopaedic Surgery (Dr. Kahlenberg), and Limb Lengthening and Complex Reconstruction Service (Dr. Fragomen and Dr. Rozbruch), Hospital for Special Surgery, New York, NY.
J Am Acad Orthop Surg. 2019 Sep 15;27(18):e819-e830. doi: 10.5435/JAAOS-D-18-00361.
Extra-articular deformities of the femur and tibia in conjunction with advanced knee osteoarthritis pose unique challenges for the arthroplasty surgeon. Careful preoperative planning is needed to evaluate both the intra- and extra-articular deformities and to determine the best route to total knee arthroplasty. An intra-articular compensatory correction can typically be performed if the extra-articular deformity is distant from the joint or if preoperative templating shows that bony cuts do not interfere with ligamentous attachments. Staged osteotomy followed by arthroplasty is beneficial in severe cases in which bony cuts are excessive or would interfere with soft-tissue structures and in cases with leg-length discrepancy. Osteotomies can be performed percutaneously and fixed with intramedullary nails, external fixators, or plate and screw constructs. Ligamentous laxity after correction and risk of peroneal nerve injury are increased in extra-articular deformity cases and must be considered during the knee arthroplasty procedure with increased implant constraint and patient counseling, respectively. Computer-assisted navigation has an emerging role in total knee arthroplasty in patients with extra-articular deformity.
股骨和胫骨的关节外畸形与晚期膝骨关节炎并存，给关节置换外科医生带来了独特的挑战。需要仔细的术前规划，以评估关节内和关节外的畸形，并确定全膝关节置换的最佳入路。如果关节外畸形远离关节，或者术前模板显示骨切不会干扰韧带附着，则通常可以进行关节内补偿性矫正。在骨切过多或会干扰软组织结构的严重情况下，或存在肢体长度差异的情况下，分期截骨后行关节置换术有益。截骨术可经皮进行，并使用髓内钉、外固定器或钢板和螺钉固定。在关节外畸形病例中，矫正后韧带松弛和腓总神经损伤的风险增加，在膝关节置换手术中需要分别考虑增加植入物约束和患者咨询。计算机辅助导航在伴有关节外畸形的全膝关节置换中具有新兴作用。
