Does tangential X-ray investigation provide diagnostic aids for subluxation of the patella and chondromalacia patellae?
Tangential X-ray visualization of the patellofemoral joint provides specific signs that may aid in diagnosing patellar subluxation and chondromalacia patellae.
The X-ray technique for the tangential visualization of the patellofemoral joint is described; 3 X-ray signs (patellofemoral angle, patellofemoral index and patellofemoral displacement) are proposed as diagnostic aids in cases of subluxation of the patella and chondromalacia patellae. Theoretically, the pathogenesis of chondromalacia patellae and patellofemoral osteoarthritis may be explained as manifestations of cartilage damage secondary to lateral patellofemoral hyperpressure and medial patellofemoral hyperpressure.
Laurin et al. (Mon,) studied this question.