Bursitis

 

Acute or chronic inflammation of a bursa.

Bursae are saclike cavities or potential cavities that contain synovial fluid located at tissue sites where friction occurs (eg, where tendons or muscles pass over bony prominences). Bursae facilitate normal movement, minimize friction between moving parts, and may communicate with joints.

Bursitis usually occurs in the shoulder (subacromial or subdeltoid bursitis). Other sites include the olecranon (miners' elbow), prepatellar (housemaid's knee) or suprapatellar, retrocalcaneal (Achilles), iliopectineal (iliopsoas), ischial (tailor's or weaver's bottom), greater trochanteric, and first metatarsal head (bunion). Bursitis may be caused by trauma, chronic overuse, inflammatory arthritis (eg, gout, RA), or acute or chronic infection (eg, pyogenic organisms, particularly Staphylococcus aureus; tuberculous organisms, which now rarely cause bursitis).

Symptoms and Signs

Acute bursitis causes pain, localized tenderness, and limited motion. Swelling and redness are frequent if the bursa is superficial (eg, prepatellar, olecranon) because the bursal wall secretes a serous effusion when inflamed. Chemical (eg, crystal-induced) or especially bacterial inflammation is particularly painful, red, and warm.

Chronic bursitis may follow previous attacks of bursitis or repeated trauma. Attacks may last a few days to several weeks, with multiple recurrences. Acute symptoms may follow unusual exercise or strain. The bursal wall is thickened, with proliferation of the synovial lining. The bursa may eventually develop adhesions, villus formation, tags, and calcareous deposits. Pain, swelling, and tenderness may lead to muscle atrophy and limited range of motion. X-rays may demonstrate subdeltoid calcific deposits, particularly in the supraspinatus tendon of the rotator cuff. In gout, crystals may be isolated in the olecranon and prepatellar bursae during acute inflammation.

Subacromial bursitis (subdeltoid bursitis) presents with localized pain and tenderness of the shoulder, particularly when abducted in an arc from 50 to 130°. Subacromial bursitis and calcific supraspinatus tendinitis may be indistinguishable clinically and on x-ray. The latter may result from partial or complete tears or from calcium apatite crystal release.

Diagnosis

Localized tenderness over the particular bursa should be elicited, or swelling or synovial fluid from superficial bursae (eg, olecranon, prepatellar) should be demonstrated. Infection should be excluded in cases of particularly painful, red, and warm swellings. Periarticular tendon or muscle tears, pyogenic bursitis, bleeding into the bursa, synovitis, osteomyelitis, and cellulitis must be ruled out. Pathologic processes may simultaneously involve a communicating bursa and joint.

Treatment

For noninfected acute bursitis, temporary rest or immobilization and high-dose NSAIDs, sometimes with narcotic analgesics, may be helpful. Voluntary movement should be increased as pain subsides. Pendulum exercises are particularly helpful for the shoulder joint. Aspiration and intrabursal injection of depot corticosteroids 0.5 to 1 mL (triamcinolone diacetate 25 or 40 mg/mL) mixed with at least 3 to 5 mL of local anesthetic after infiltration with 1% local anesthetic (eg, lidocaine) is the treatment of choice when rest alone is inadequate. The depot corticosteroid dose and volume of mixture are gauged to the size of the bursa. Reaspiration and injection may be required with resistant inflammation. Systemic corticosteroids (prednisone 15 to 30 mg/day or equivalent for 3 days) are occasionally indicated in resistant acute cases after infection and gout have been excluded.

Chronic bursitis is treated as acute bursitis, except that splinting and rest are less likely to be helpful. Rarely, surgical removal or large-needle aspiration of radiologically demonstrated calcification in chronic calcific supraspinatus tendinitis may be necessary if corticosteroid injections are not helpful. Disabling adhesive capsulitis of the shoulder may require repeated corticosteroid injections in multiple intra- and extra-articular areas and intensive physical therapy. Manipulation under anesthesia does not improve long-term results unless measures to correct adhesive capsulitis are followed. Muscle atrophy should be corrected with exercise to reestablish range of motion and strength. Infection requires antibiotics and drainage or excision therapy. Bursitis may recur if the underlying cause (eg, RA, gout, chronic occupational strain) is not corrected.