A Rare Cause of Shoulder Pain: Ganglion Cyst of the Acromioclavicular Joint
A ganglion cyst may have an acute or chronic onset and is generally related to repeated
microtrauma of the wrist dorsum.
The differential diagnosis of shoulder pain and functional
disorders includes shoulder compression syndromes, glenohumeral instability,
rotator cuff diseases, tendonitis, adhesive capsulitis, trauma, cervical radiculopathies,
neoplasms, degenerative diseases, acromioclavicular joint separation, arthritic variations,
crystal arthropathies and atypical emplacement of a GC.
This paper reports a patient with shoulder pain due to a GC in the AC joint who presented to
our clinic along with the post-operative evaluation.
A 65-year-old man presented to our clinic complaining of a slow-growing swelling and right
shoulder pain that began one year previously. Physical examination showed a 10×8×5 cm
soft, slightly painful mass above the right AC joint, slightly limiting shoulder range of motion.
A direct x-ray showed arthritic changes in the right AC joint.
Magnetic resonance imaging showed a 10×8×5 cm mass related to the right AC joint,
that was tentatively diagnosed as a GC, and partial rupture of the supraspinatus muscle.
The patient’s complaint persisted despite three months of physical therapy and surgery was
planned. Under general anesthesia in the chaise longue position, the mass on the right AC joint
was entered with a fish-mouth incision.
The mass was observed to be connected to the AC joint and an excision biopsy was performed. Histopathology showed that the mass was
consistent with GC.
There was no recurrence at the 1.5-year follow-up. His pain resolved and
ROM was normal despite partial rupture of the supraspinatus.
Osteol Rheumatol Open J. 2016; 1(1): 20-22. doi: 10.17140/ORHOJ-1-107