Ganglia

Clinical appearance

Ganglia are ubiquitous uni- or multilocular cystic lesions that arise in paratendinous, pararticular, or intraosseous locations (9). Pararticular lesions communicate with the joint unidirectionally via a narrow and tortuous stalk, resulting in enlargement following excessive joint use. Nerve compression may result (Table 4). Common locations of ganglia include the vicinity of the A1 pulley in the digital flexor sheath, the dorsum of the wrist, the carpal tunnel region causing the carpal tunnel syndrome (Figure 1), and the dorsum of the foot. Unusual locations include the scapula at the suprascapular or the spinoglenoid notch, the vicinity of the proximal fibular head, the popliteal fossa, and intraosseous sites. Scapular and fibular lesions may cause suprascapular and common peroneal nerve compression neuropathy, respectively.

Ganglia can be confidently diagnosed in most cases on the basis of location, typical increase in size and symptoms caused by joint use, and palpatory findings (cystic). Aspiration, which must be made with a large-bore needle, yields a thick jelly-like material. Echography, computed tomography (CT), and magnetic resonance imaging (MRI) facilitate the diagnosis of ganglia that occur in deep and atypical locations.

Differential diagnosis

It is essential to rule out a malignant tumor. An imaging procedure should be performed whenever there is doubt about the diagnosis. Because of its low cost and excellent resolution, echography is a useful imaging procedure to investigate soft tissue lesions.

Treatment

Surprisingly, little research has been done on ganglia. There are no published controlled trials comparing different forms of treatment. Aspiration followed by injection of a long-acting corticosteroid is an appropriate treatment. Technical details can be found in the accompanying article. Surgery is generally required for lesions greater than 3 cm in diameter, for anterior wrist ganglia, and for intraosseous ganglia, as well as in cases where there is nerve compression.

Role of the primary care physician

Most ganglia can be treated by primary care physicians. Lesions that are not amenable to infiltration should be appropriately referred for surgical resection.

Key issues

Ganglia are common and can cause compression neuropathies that necessitate surgical resection. However, the majority of ganglia can be treated by aspiration and corticosteroid infiltration.