The biceps brachii tendon runs over the cranioproximal humerus, protected by a synovial bursa. Inflammation of this structure can cause lameness and is usually secondary to a more serious inciting cause. Trauma to the proximal humerus, cystic lesions in the underlying bone, and injury to the tendon itself will cause secondary bursitis; it is important to recognize the primary lesion and treat appropriately. Occasionally, idiopathic primary bursitis arises and responds very well to medication of the bursa with corticosteroids. Bacterial contamination and, rarely, fungal infections can cause bicipital bursitis. In most cases, a wound in the vicinity of the bursa alerts the clinician to this possibility but, very rarely, closed sepsis can occur. Treatment for septic bursitis follows the same pattern as for other synovial structures. Radiography and ultrasonography complement each other in the diagnosis and management of primary and secondary bursitis. Repeat examinations may be necessary if a primary lesion cannot be detected, because it may become obvious with time. Scintigraphy is useful in cases in which the primary lesion remains elusive, because small areas of bone damage or cavitation can go undetected radiographically.