Total knee arthroplasty.

Eighty-six nonhinged total knee arthroplasties performed between 1971 and 1981 have been reviewed. Fifty-one were of the geometric type and 35 of the anametric type. The use of both units resulted in a statistically and clinically significant improvement in preoperative pain and an increase in functional activities. Three of 51 geometric units developed loose components that required revision. None of the 35 anametric units has required revision for loosening. Partial radiolucent lines at the tibial bone-cement interface were noted in 43% of the group. Data analysis of age, weight, and sex demonstrated no statistically significant characteristic of this group when compared with the group without radiolucent lines. However, radiolucent lines were more common in those patients with osteoarthritis than in the group with rheumatoid arthritis. In addition, radiolucent lines were noted in 90% of knees in which a metal-backed tibial tray with a central post was used, compared with 36% of knees without metal-backed tibial components. Relief of pain and correction of instability and deformity can be achieved for most patients following nonhinged total knee arthroplasty.