Cellulitis of the forearm is usually a sequel to one of the deeper varieties of whitlow.
In the region of the elbow-joint, cellulitis is common around the olecranon. It may originate as an inflammation of the olecranon bursa, or may invade the bursa secondarily. In exceptional cases the elbow-joint is also involved.
Cellulitis of the axilla may originate in suppuration in the lymph glands, following an infected wound of the hand, or it may spread from a septic wound on the chest wall or in the neck. In some cases it is impossible to discover the primary seat of infection. A firm, brawny swelling forms in the armpit and extends on to the chest wall. It is attended with great pain, which is increased on moving the arm, and there is marked constitutional disturbance. When suppuration occurs, its spread is limited by the attachments of the axillary fascia, and the pus tends to burrow on to the chest wall beneath the pectoral muscles, and upwards towards the shoulder-joint, which may become infected. When the pus forms in the axillary space, the treatment consists in making free incisions, which should be placed on the thoracic side of the axilla to avoid the axillary vessels and nerves. If the pus spreads on to the chest wall, the abscess should be opened below the clavicle by Hilton's method, and a counter opening may be made in the axilla.
Cellulitis of the sole of the foot may follow whitlow of the toes.
In the region of the ankle cellulitis is not common; but around the knee it frequently occurs in relation to the prepatellar bursa and to the popliteal lymph glands, and may endanger the knee-joint. It is also met with in the groin following on inflammation and suppuration of the inguinal glands, and cases are recorded in which the sloughing process has implicated the femoral vessels and led to secondary hæmorrhage.
Cellulitis of the scalp, orbit, neck, pelvis, and perineum will be considered with the diseases of these regions.