抄録
Between 1973 and 1988, 11 patients with spastic cerebral palsy underwent patellar advancement operations for correction of the patella alta and knee flexion deformity. Seven of these patients had both knees operated on, so that in all, there were 18 operations. The average age at the time of operation was 21 years and 11 months and the average follow up, 7 years and 3 months.
To determine patellar height, the ratio of the articular length of the patella to height of the lower pole of the articular cartilage above the tibial plateau, is calculated from a lateral radiograph of the knee, flexed beyond 30 degrees. According to Blackburne's criteria, normal values lie between 0.54 and 1.06. In our case, the mean value at pre-operation was 1.16, and that at post-operation, 0.57.
By bringing the patella down to normal position, the leverage of the quadriceps femoris is reestablished and full extension of the knee in all patients is made possible.
