Instability after total knee arthroplasty (TKA) remains one of the major reasons for revision surgery. The causes relate to both the soft tissues and the implant positioning. TKA is a procedure that is dependent upon balanced flexion and extension gaps, appropriate overall limb alignment, and appropriate positioning of the implants to the underlying bone. At times it may be possible to revise one of the components. However, because the operative procedure is a combination of bone and soft tissue surgery, it is imperative to address all of the problems at the same time, and this often requires complete revision of the implant.
KeywordsInstability Revision Kinematic Alignment Loosening Gaps
Intraoperative demonstration of the global instability prior to surgical correction. Note the laxity with the knee in full extension in the coronal plane and with the knee at 90° of flexion in the sagittal plane (MPG 19222 kb)
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