The clinical presentation is consistent with Charcot neuroarthropathy of the shoulder. The most common cause of neuropathic arthropathy of the shoulder is syringomyelia, although chronic alcoholism and diabetes have also been reported.
Workup for neuropathic arthropathy of the shoulder includes magnetic resonance images of the cervical spine, to look for a syrinx of the central cord.
Hatzis et al retrospectively reviewed a series of patients with neuropathic arthropathy of the shoulder. The etiology of the neuropathic condition was most commonly syringomyelia. They reported that the diagnosis is often missed, and inappropriate surgeries were frequently performed for this etiology.
Clayton et al also reviewed Charcot arthropathy of the shoulder and concluded that although rare, diabetes mellitus should always be ruled out as a cause for this disorder. They report that treatment should not be different with diabetes as the etiology.
Figure A shows a proximal humerus with significant destruction and fragmentation, consistent with Charcot neuroarthropathy
Answer 1: Diabetes is a documented cause of Charcot neuroarthropathy of the shoulder, but is less common than Syringomyelia.
Answer 2: Syphilis is no longer the most common cause of these findings.
Answer 3: Alcoholism is a documented cause of Charcot neuroarthropathy of the shoulder, but is less common than Syringomyelia.
Answer 5: There is no documented association between Charcot neuroarthropathy and uremia.
Hatzis N, Kaar TK, Wirth MA, Toro F, Rockwood CA, Jr. Neuropathic arthropathy of the shoulder. J Bone Joint Surg Am 1998;80:1314-9
PMID:9759816 (Link to Abstract)
Clayton M, Taylor BC, Backes J. Diabetic neuroarthropathy of the shoulder. Orthopedics. 2010 Aug 11;33(8).
PMID:20704097 (Link to Abstract)