Figure 8.

Joint contamination in osteomyelitis. Schematic drawings (a) and (b), coronal (c) and axial (d) T1–WI Fat–Sat after gadolinium contrast administration. (a) shows a joint in which the joint capsule (blue) is attaching underneath the growth plate. This intra-articular location of the growth plate may lead to rapid spread of infection into the adjacent joint. (b) shows a joint in which the joint capsule (blue) is attaching above the growth plate. An extra-articularly located growth plate protects against early joint contamination. (c, d). Example on MRI of a patient with rapid spread of the infectious focus to the adjacent left shoulder joint. Because the joint capsule of the shoulder insert below the growth plate, metaphyseal osteomyelitis may easily spread through the medial cortex directly into the joint resulting in synovial enhancement (white arrow).