[Subjective evaluation of surgical treatment for patellar instability]

We analyzed functional outcome after surgical treatment for patellar instability.

This study included 130 patients (174 knees) treated between 1988 and 1999. Minimum follow-up after surgery was two Years, mean five years (range 24-152 months). The IKDC 1999 subjective evaluation chart was used. This chart has ten items to establish level of sports activity and functional status of the knee for daily life activities. One hundred ten patients (84.5%) responded to the questionnaire.

Eighty-eight patients were seen for clinical assessment and 22 were questioned by telephone: 104 patients (94.5%) were satisfied or very satisfied, five (4.5%) were dissatisfied, and one was disappointed. We evaluated results on the basis of pain (37.6% with climate-related pain or discomfort), residual effusion, and sensation of blocked knee (15.8%), as well as daily activities (68% with discomfort when kneeling), and sports activities (with level of activity).

The patients' subjective assessment showed that surgical treatment with medialization and/or lowering of the anterior tibial tuberosity is effective with a good or excellent rate of satisfaction. The quality of these results was directly related to careful individualization of the lesions with systematic analysis of factors leading to patellar instability (trochlear dysplasia, patellar height, quadriceps dysplasia, TA-GT measures, length of the patellar tendon).