Rotating hinged total knee replacement: use with caution.

Background: A rotating hinged total knee prosthesis may be utilized for the treatment of global instability or severe bone loss around the knee. Older generations of rotating hinged designs were associated with suboptimal outcomes. We evaluated the outcome of salvage knee reconstructions that had been performed with use of modern-generation modular segmental kinematic rotating hinged total knee prostheses.

Methods: The cohort included forty-three patients (twenty-nine women and fourteen men) who underwent forty-four knee arthroplasties for the treatment of a non-neoplastic condition with use of a modern-generation kinematic rotating hinged prosthesis. Revision of a previous total knee arthroplasty in the presence of massive bone loss was the most common indication for surgery. Complete clinical and radiographic data were collected for all patients after a mean duration of follow-up of 4.2 years.

Results: Reconstruction with a rotating hinged total knee prosthesis provided substantial improvement in function and reduction in pain. However, a relatively large number of complications and failures (including revision because of periprosthetic infection [three knees], aseptic loosening [four], and periprosthetic fracture [one]) were encountered, with a mean time to failure of 1.7 years. The rate of prosthetic survival was 79.6% at one year and 68.2% at five years with revision or reoperation as the end point.

Conclusions: The present study highlights the commonly held opinion that a modular kinematic rotating hinged total knee prosthesis has a role for salvage reconstruction of the knee. In light of the relatively high rate of complications, we believe that this salvage procedure should be reserved primarily for elderly and sedentary patients.