Syringomyelia presenting as shoulder instability.

Area of Science:

• Neurology
• Orthopedic Surgery
• Radiology

Background:

• Shoulder instability is a common orthopedic complaint.
• Syringomyelia is a rare condition characterized by cyst formation within the spinal cord.
• The association between syringomyelia and shoulder instability is not widely recognized.

Purpose of the Study:

• To highlight shoulder instability as a potential presenting symptom of syringomyelia in middle-aged adults.
• To emphasize the importance of considering syringomyelia in the differential diagnosis of shoulder instability, particularly in older patients.
• To report on the diagnostic process and outcomes for patients with syringomyelia presenting with shoulder issues.

Main Methods:

• Case series presentation of three middle-aged women with shoulder instability as the initial symptom.
• Review of clinical presentations, surgical histories, and radiographic findings.
• Diagnostic confirmation using myelography, computed tomographic (CT) scanning, and magnetic resonance imaging (MRI).

Main Results:

• All three patients presented with unilateral shoulder instability (two posterior, one anterior).
• Two patients had undergone unsuccessful shoulder stabilization surgery prior to diagnosis.
• Radiographic evidence suggested neuropathic arthropathy in two patients; syringomyelia was confirmed via advanced imaging.
• One patient with an Arnold-Chiari malformation received a syringosubarachnoid shunt.

Conclusions:

• Shoulder instability can be an initial manifestation of syringomyelia, even in patients over 40.
• Neuropathic arthropathy should be suspected in older adults with glenohumeral dislocations.
• Including syringomyelia in the differential diagnosis can prevent unnecessary and ineffective surgical interventions for shoulder instability.