The Posterior Axial Oblique Projection for Radiographic Examination of the Patella.

BACKGROUND: Images of the patella are invaluable for demonstrating fractures, acute injuries, and degenerative pathology of the patellar region. However, quality images of the patella can be difficult to acquire because of the distal femur obscuration. This article presents a method of imaging the patella, using film-screen radiography, computed radiography, or digital radiography that virtually eliminates the problem associated with distal femur obscuration and describes 7 radiography cases that demonstrate the clinical utility of the method.

DISCUSSION: The described method of imaging the patella is simple, reproducible, and uses 2 projections-the posterolateral axial oblique and the posteromedial axial oblique-which help eliminate distal femur obscuration.

CONCLUSION: The presented method demonstrates the base, body, apical, lateral, and medial borders of the patella without significant distal femur obscuration. In addition, radiologists and orthopedic surgeons express positive impressions of the resulting images' diagnostic usefulness.