Resurfacing of the patella in the total knee arthroplasty(TKA) has been controversial. Most authors have reported more favorabley on patellar resurfacing. Ranawat 16) reported 90% to 95% good or excellent result in patients in patients in whom
routine
patellofemoral replacement had been done.
However, patellar resurfacing has been reported to be associated with a rate of colmplication of 5% to 30%. The complications have included wear of the component, loosening, fracture, ligament and tendon ruptures, maltracking and anterior knee
pain.
Because of this potential major complications, more recently some surgeons have recommended selective retension of the patella.
To evaluate the functional otcome, we reviewed our experience with 102 TKAs(64patients) that had been done with or without patella resurfacing.
Diagnosis was all osteoarthritis. There were 45 females973 knees) and 19 males929 knees). The average age was 68years9range, 43 to 84 years0. Thirty-eight patients had bilateral TKAs. The average duration of follow-up 7 years9range, 3 years and 6
months
to 10 years).
Operations were performed by in the two surgeons in the two hospitals.
The surgical technique was similar in all cases using a medial parapatellar approach and PFC prosthesis. Patellar retention was determined by two different methods. In group 1, we did not resurface if they meet all of the following criteria: (1)
the
presence of symmetrical cartilage space on preoperative skyline view; (2) abcence of eburnated bone at tme of sargery; (3) a normal anatomic shape of the patella. In group 2, we selected the patient randomly and body weight of the group 2
patients
was
lees than 60Kgs. Decision of the retention was not determined by intraoperative pathology.
Outcome was assessed by the knee pain walking distance, stair climbing, rising from a chair and Range of motion(ROM) of knee. We also compared the results according to the body weight of the not-resurfaced patients.
In the subiective symptoms, patellar function and knee score, there was no difference between the patellar retention and resurfacing group.
The use of an appropriate prosthetic design and careful surgical technique can provide equivealent results after TKAs with or without patellar resurfacing and body weight was consibered as an influencing factor on the final results.
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