In revision total knee arthroplasty (TKA), control of the patellar height and the joint line is difficult. Therefore, we developed an adjustable flexion-extension spacer, the Knee Joint-line Balancer (KJB®). This device simulates femur component sizes, polyethylene sizes, the joint-line level, and distal femur wedges. The goal of this study is to evaluate the use of an adjustable knee spacer to control patellar height and joint-line during revision total knee surgery. The subjects of the study were the first 10 consecutive patients who had undergone revision of a primary TKA where the KJB was used. A reference group composed of the last 10 patients treated without the use of the KJB was also evaluated. The joint-line position and the patellar height were determined before and after revision TKA. The method described by Figgie et al. [J. Bone Jt. Surg., Am. 68 (1986) 1035] was used. The patellar height in the reference group averaged 7.7 mm. Seven of 10 patients had a patella baja, and two of these patients had patellar impingement. One patient needed a proximalisation of the tuberositas. The patellar height in the KJB group averaged 14.6 mm after revision, with only one patient having a patella baja. This new device, adjustable kneespacer for revision TKA ("the KJB"), seems to provide better control of the patellar position in total knee revision. © 2004 Elsevier B.V. All rights reserved.
Ten Ham, A. M., Wymenga, A. B., & Jacobs, W. C. H. (2005). The use of the knee joint-line balancer to control patella position in revision total knee arthroplasty. Knee, 12(2), 89–92. https://doi.org/10.1016/j.knee.2004.05.004