Background: Whether to resurface the patella
during a primary total knee arthroplasty performed for the treatment
of degenerative osteoarthritis remains a controversial issue. Parameters
that have been suggested as being useful in guiding this decision include
patient height and weight, the presence of anterior knee pain preoperatively,
and the grade of chondromalacia encountered intraoperatively. The
purpose of this study was to determine whether these parameters
were predictive of the clinical result following total knee arthroplasty
with or without patellar resurfacing.
Methods: Eighty-six patients (118 knees) undergoing
primary total knee arthroplasty for the treatment of osteoarthritis
were enrolled in a prospective, randomized, double-blind study.
All patients received the same posterior-cruciate-sparing total knee
prosthetic components. Patients were randomized to treatment with
or without resurfacing of the patella. Evaluations consisted of
the determination of a Knee Society clinical score, the completion
of a patient satisfaction questionnaire, specific questions relating
to patellofemoral symptoms, and radiographs. Sixty-seven patients
(ninety-three knees) were followed for a minimum of five years (range,
sixty to eighty-four months; average, 70.5 months).
Results: With the numbers available, there was no
significant difference between the groups treated with and without
resurfacing with regard to the overall Knee Society score or the
pain and function subscores. Obesity, the degree of patellar chondromalacia,
and the presence of preoperative anterior knee pain did not predict
postoperative clinical scores or the presence of postoperative anterior
Conclusions: The occurrence of anterior knee pain
could not be predicted with any clinical or radiographic parameter
studied. On the basis of these results, it seems likely that postoperative
anterior knee pain is related either to the component design or
to the details of the surgical technique, such as component rotation,
rather than to whether or not the patella is resurfaced.