Is conventional radiography still relevant for evaluating the acromioclavicular joint?

Conventional radiography using an anteroposterior view of the acromioclavicular (AC) joint is the gold standard for evaluating arthritic degeneration.

Based on a standardised AP view of the AC joint, the objective of this study was to determine whether this radiographic view is reliable and reproducible for evaluating the AC joint space.

A cadaver scapula-clavicle unit, free of osteoarthritis, was used for this study. The scapula was positioned in a stand; and then with fluoroscopy guidance, a strict AP view of the AC joint was taken. Starting from this "0" position, a radiograph was taken by varying the angle by 5°, 10°, and 15° in every plane in space. All radiographs were taken during a single session to ensure the distance between the X-ray tube and scapula did not change. The images were then exported to OsiriX for processing; the superior and inferior AC distance and the joint area were measured.

There was no reproducibility in the AC joint measurements as a function of the incidence angle relative to a strict AP view.

Conventional radiography using an AP view of the AC joint cannot be used to do a fine analysis of arthritic degeneration of this joint. It is likely that only CT scan or MRI is sufficient to analyse osteoarthritis in this joint.

IV, basic science study.