Reduction In The Patella Tendon After Total Knee Arthroplasty And Its Effect

Objective To study the change in the length of patellar tendon after total knee arthroplasty, compare the effect of patella resurfacing on the tendon length and the correlation between the length change and the range of motion.Methods Fifty-five knees were treated with primary total knee arthroplasty in forty-nine patients(six of whom had a bilateral procedure)between may 2002 and december 2003 by one group of surgeons. There were 7 males and 42 females, the average age was 66.5. Diagnoses included osteoarthritis in 48 knees and rheumatoid arthritis in 7 knees . Seven knees were treated with lateral retinaculum release additionally. Measured the length of patellar tendon before and one year after operation, recorded the range of motion the same time postoperatively. By the patella resurfaced or not ,all the knees were divided into two groups and compared the incidence of tendon shortenings which were more than 10% of the original length. Statistical analysis was made within and between groups.Results One year after operation, the patellar tendon had generated significant reduction and the incidence of the reductions that were more than 10% failed to show significant difference between two groups divided by patella resurfacing. Reduction of patellar tendon showed a negative correlation with the the range of motion postoperatively.Conclusions There is complication of patellar tendon reduction after total knee arthroplasty. Patella resurfacing has no effect on the reduction of patellar tendon. Reduction of patellar tendon may be one of the reasons that cause the motion restriction of the knee postoperatively.