The aim is of this prospective randomised study was to investigate the necessity of resurfacing the patella in combination with total knee arthroplasty in patients without or mild anterior knee pain before undergoing total knee replacement.
Between May 1999 and May 2000 fifty patients were enrolled in a prospective, randomised study. All patients received the same posterior-cruciate-sparing total knee replacement and were randomised to treatment with and without resurfacing of the patella. Inclusion criteria were primary osteoarthritis of the knee, preoperatively no pain when the patella was shifted during clinical examination, a maximal grade III radiological degeneration of the patella according to Sperner et al. and at most a mild anterior knee pain in preoperative interview. Evaluations consisted of the determination of the Knee Society clinical score, the completion of a patient satisfaction questionnaire, and radiographic assessment basing on the Knee Society roentgenographic evaluation and scoring system. All patients were examined preoperatively and 3, 6, and 12 months postoperatively.
In all postoperative examinations patients with patella resurfacing demonstrated a higher overall Knee Society score. At month 6 the difference was statistically significant. The patient satisfaction questionnaire demonstrated no significant difference between both groups. However, regarding to relief of anterior knee pain and improvement of pain in general patients with nonresurfacing were less satisfied at all follow-ups. Furthermore, after 12 months all answers to the patient satisfaction questionnaire of the resurfaced group were better. Patella-associated revisions were performed in two patients without resurfacing. Radiographic analysis demonstrated no loosening, fracture, subluxation or dislocation.
The presented study demonstrated after one year follow-up a better functional result, a higher degree of contentment and fewer complications after total knee replacement with patella resurfacing in patients without or mild preoperative anterior knee pain.