Progression of radiolucent lines in cementless twin-bearing low-contact-stress knee prostheses

A total of 134 low-contact-stress (LCS) total knee arthroplasties (TKAs) with mobile meniscal bearings were implanted in 121 patients with a mean age of 74 years (range, 49–91 years) at the time of surgery. The radiographic results obtained from 91 prostheses at an average follow-up of 7.5 years (range, 4.8–9.6 years) showed that radiolucent lines (RLL) appeared most frequently near the tibial plateau (97%) and that most RLL were present immediately postoperatively (67%) or appeared within the first year (96%). RLL were predominantly nonprogressive (99%). Progressive RLL did not affect the fixation or stability of the prosthesis. There were no revisions for aseptic loosening. Cementless LCS TKA achieves excellent radiologic and clinical midterm results.