The patello-femoral joint. Methods of diagnosis: clinical disorders and their treatment.

The knee has two joints, the tibio-femoral and the -patello-femoral, but until recent years the second has received relatively little attention. This neglect is surprising, because the importance of lesions of the extensor mechanism, and the need for a powerful quadriceps muscle, have long been appreciated. This article surveys first the methods of examination of the patello-femoral joint, then its disorders, and finally the operation of patellectomy. The disorders are in two main gioups: displacements (subluxation and dislocation) and degenerations (chondromalacia and osteoarthritis). All these conditions are linked, for recurrent dislocation and subluxation are potent causes of chondromalacia which, in turn, is a forerunner of osteoarthritis.