Age-related changes in marrow distribution in the shoulder: MR imaging findings.

PURPOSE: To define age-specific patterns of distribution of red and yellow marrow about the shoulder. MATERIALS AND METHODS: Red and yellow marrow distribution was reviewed on magnetic resonance images of 189 subjects aged 15-69 years. Double-echo and fast spin-echo, gradient, and short inversion time inversion recovery pulse sequences were used. The acromion, glenoid, and proximal humeral epiphysis, metaphysis, and diaphysis in each shoulder were graded semiquantitatively and qualitatively. RESULTS: There was a wide variation in the normal pattern of red-yellow marrow distribution both among subjects and among locations. All five anatomic locations showed an orderly progression from greater to lesser amounts of red marrow with increasing age. Many of the subjects had focal subchondral red marrow in the epiphysis, which was associated with patient age (P = .0001) and gender (P = .04). CONCLUSION: Knowledge of normal patterns of marrow distribution can prevent their being misinterpreted as marrow-based disease.