Case 91 - Ganglion cyst

Summary

Imaging description

Based on location there are two major types of ganglion cysts: intraosseous and soft tissue ganglia. Under the soft tissue variant there are a few subtypes which include dorsal wrist ganglia, periosteal or subperiosteal ganglia, intra-articular ganglia, and intraneural ganglia. The intraosseous ganglion is a relatively uncommon, benign, cyst-like, multiloculated lesion that occurs in young and middle-aged adults, usually located in the end of long bones. The most common locations for intraosseous ganglion cysts include the medial malleolus, femoral head, proximal tibia, and carpal bones (Figure 91.1).

Ganglion cyst is the most common soft tissue tumor of the hand and wrist (Figure 91.2). In the carpus ganglion cysts have been described in the capitate, lunate, pisiform, and scaphoid. Radiolucent lesions in the carpal bones are commonly encountered and they are often seen incidentally in asymptomatic patients.

With the widespread use of MRI for the study of internal derangement of the knee and shoulder, intra-articular ganglion cysts are often encountered arising from the cruciate ligaments (Figure 91.3), and within the suprascapular and spinoglenoid notches of the scapula where they are implicated in producing entrapment neuropathies.

Intraneural ganglion cysts are rare. They most commonly involve the peroneal nerve in the region of the fibular head and neck (Figure 91.4). Familiarity with this lesion can help in explaining neurological symptoms such as pain, paresthesia, and foot drop.