Can Ganglion Cysts Occur on the Forearm?
Yes, ganglion cysts can occur on the forearm, though they are less common at this location compared to the wrist and hand. While ganglion cysts most frequently develop at the dorsal or volar aspects of the wrist, they can arise from tendon sheaths, joints, and ligaments throughout the upper extremity, including the forearm 1, 2, 3.
Anatomic Distribution
Ganglion cysts can develop in tendon sheaths, joints, and ligaments throughout the hand and upper extremity, making forearm locations anatomically possible 1, 2.
The most common locations remain the wrist (dorsal and volar aspects), followed by flexor tendon sheaths, interphalangeal joints, and extensor tendons, but forearm presentations are documented 3.
A documented case report demonstrates median nerve neuropathy in the distal forearm caused by a recurrent anterior wrist ganglion that expanded beyond the wrist into the forearm, confirming that these cysts can extend into or originate in forearm tissue 4.
Diagnostic Approach for Forearm Masses
When evaluating a suspected ganglion cyst on the forearm:
Start with radiographs as the initial imaging modality for any soft-tissue mass in the forearm, as they can identify mineralization, foreign bodies, or bone changes that influence treatment 5.
Ultrasound is recommended as the initial imaging modality to confirm the fluid-filled nature of suspected ganglion cysts in the appropriate clinical setting 6, 1, 2.
Ultrasound is particularly useful for differentiating solid from cystic lesions and confirming fluid content 5.
MRI is reserved for suspected occult ganglion cysts, when there's concern about solid tumors, or when ultrasound findings are atypical 6, 1, 2.
Important Clinical Caveat
Forearm ganglion cysts may represent extension from wrist-based cysts rather than primary forearm origin, as demonstrated in the case where an anterior wrist ganglion from the scaphotrapezial joint expanded into the distal forearm 4.
These cysts can cause nerve compression symptoms (numbness, pain, weakness) when they expand in the forearm, particularly affecting the median nerve 4.
Incomplete resection of wrist ganglions can lead to recurrence with proximal extension into the forearm, requiring careful surgical planning to address the origin at the joint level 4.