Chondromalacia and recurrent subluxation of the patella: a study of malalignment, with some indications for radiography.

The authors adopted four parameters in a study of 100 normal subjects and fifty patients affected by "chondromalacia" or by recurrent subluxation of the patella. These were: the quadriceps angle, the ratio between the length of the patellar tendon and the length of the patella, the femoral sulcus angle, and the congruence angle between the femur and patella. These parameters showed a statistically significant increase in the pathological group, thereby demonstrating that the majority of cases of "chondromalacia" of the patella and those of recurrent subluxation constitute two entities forming part of the same disease, the basis of which is malalignment and malposition of the patella.