The invention relates to the discovery that collagenase injections are effective in lyse the collagenous adhesions in the shoulder and treat the disorder, adhesive capsulitis. As such, the invention relates to methods of treating or preventing adhesive capsulitis, or frozen shoulder, in a patient in need of such treatment comprising injecting or otherwise delivering an effective amount of collagenase to the collagenous adhesions in the shoulder. The invention also relates to the use of collagenase in the manufacture of a medicament to treat adhesive capsulitis.