Chapter 180. Acute Disorders of the Joints and Bursae

Acute disorders of the joints and bursae are common emergency conditions that involve a wide spectrum of ages, acuities, and etiologies. Mismanagement of certain pathologic entities can lead to significant morbidity for the patient.

Multiple pathways can cause disruption of the normal joint milieu leading to acute joint complaints. These pathways include degeneration of articular cartilage (osteoarthritis), deposition of immune complexes (rheumatoid arthritis), crystal-induced inflammation (gout and pseudogout), seronegative spondyloarthropathies (ankylosing spondylitis and Reiter syndrome), and bacterial and viral invasion (septic arthritis). These pathologic events invariably lead to pain, the most common complaint of patients with a joint problem. Important historical factors to elicit include a determination of previous joint or bursal disease; presence of constitutional symptoms; and whether the pain is acute, chronic, or acute on chronic. Determining the number and distribution of joints affected as can help narrow the differential diagnosis (Table 180-1). Systemic lupus erythematosus may present with a migratory pattern of joint pain, while migratory pain is characteristic of the following infectious etiologies: gonococcal arthritis, acute rheumatic fever, Lyme disease, and viral arthritis.

On physical examination, arthritis should be distinguished from more focal periarticular inflammatory processes such as cellulitis, bursitis, and tendonitis. True arthritis produces joint pain exacerbated by active and passive motions.

With the exception of recent joint surgery or cellulitis overlying a prosthetic knee or hip, history, physical examination, and routine blood tests do not distinguish acute septic arthritis from other forms of arthritis. Clinicians who suspect septic arthritis based on the patient's presentation should perform arthrocentesis. Synovial fluid should be sent for culture, Gram stain, cell count, and crystal evaluation (Table 180–2). Except in pediatric septic arthritis, where the erythrocyte sedimentation rate has been shown to have a 90% sensitivity, the serum white blood cell count and erythrocyte sedimentation rate lack the sensitivity and specificity to be reliable discriminators in disorders of the joints and bursae. Adults with risks for sexually transmitted disease and migratory symptoms and or tenosynovitis should be evaluated for gonococcal arthritis.

Radiographs should be obtained when the differential diagnosis includes trauma, tumor, osteomyelitis, ankylosing spondylitis, or avascular necrosis. More sophisticated modalities such as computed tomography, magnetic resonance imaging, and radioisotope scanning are used in isolated cases.

Septic arthritis is a condition that can rapidly lead to irreversible joint destruction if inadequately treated. It typically presents as a monoarticular arthritis and may be associated with fever, chills, or malaise, although absence of these symptoms does not exclude the diagnosis. The synovial fluid confirms the diagnosis. Therapy requires admission for parenteral antibiotics and repeated needle aspiration, arthroscopy, or open surgical drainage. Specific patient demographics can help guide empiric antibiotic therapy in septic arthritis (Table 180–3).

Traumatic hemarthrosis is associated with intraarticular fracture or ligamentous injury. Aspiration of large effusions may decrease pain and increase range of motion. Treatment is supportive. Spontaneous hemarthrosis may be associated with coagulopathies requiring specific clotting factor replacement. It is usually not recommended to aspirate spontaneous hemarthroses.

Crystal-induced synovitis generally affects middle-age to elderly patients. Gout (uric acid crystals) typically affects the great toe, tarsal joints, and knee, whereas pseudogout (calcium pyrophosphate crystals) typically affects the knee, wrist, ankle, and elbow. Pain with gout usually evolves over hours, whereas the pain associated with pseudogout occurs over a day or more. Either condition may be precipitated by trauma, surgery, significant illness, dietary or alcohol indiscretions, or certain medications. The synovial fluid is inflammatory with negative birefringent needle-shaped (gout) or weakly positive birefringent rhomboid (pseudogout) crystals. Treatment is with nonsteroidal anti-inflammatory drugs (eg, oral indomethacin 50 mg 3 times daily for 3 to 5 days) and opioid analgesics. Although not routinely necessary, colchicine (0.6 milligram/h PO until resolution of symptoms or intolerable gastrointestinal side effects) may be used as a complementary therapy.

Osteoarthritis is a chronic, symmetric, polyarticular destruction of joints (including the distal interphalangeal) distinguished by a lack of constitutional symptoms. Patients may present with acute monoarticular exacerbations with small, noninflammatory synovial fluid collections and characteristic joint space narrowing on radiographs. Treatment involves rest and analgesics.

Lyme arthritis is a monoarticular or symmetric oligoarticular arthritis (especially of the large joints) with brief exacerbations followed by complete remission occurring weeks to years after the primary infection. Synovial fluid is inflammatory with usually negative cultures. Treatment with appropriate antibiotics (doxycycline, erythromycin, or amoxicillin) for 3 to 4 weeks is effective.

Gonococcal arthritis is an immune-mediated infectious arthritis that typically affects adolescents and young adults. Fever, chills, and a migratory tenosynovitis or arthralgias typically precede mono- or oligoarthritis. Vesiculopustular lesions on the distal extremities are characteristic. Synovial fluid is usually inflammatory and often culture negative; cultures of the pharynx, urethra, cervix, and rectum increase the culture yield. The patient should be admitted for pain control and parenteral antibiotic therapy. Orthopedic consultation is advised.

Reiter syndrome is a seronegative reactive spondyloarthropathy characterized by acute asymmetric oligoarthritis (especially of the lower extremities) preceded 2 to 6 weeks by an infectious illness such as urethritis (Ureaplasma or Chlamydia) or enteric infection (Salmonella or Shigella). The classic triad of arthritis, conjunctivitis, and urethritis is not required for diagnosis. Synovial fluid is inflammatory. Treatment is symptomatic, and antibiotics have not been found to be useful.

Ankylosing spondylitis is a seronegative spondyloarthropathy that primarily affects the spine and pelvis and may be associated with morning stiffness and constitutional symptoms such as fatigue and weakness. Hereditary predilection (HLA-B27 antigen or absence of rheumatoid factor) is significant. Radiographic findings include sacroiliitis and squaring of the vertebral bodies (bamboo spine). Treatment is symptomatic.

Rheumatoid arthritis is a chronic, symmetric, polyarticular joint disease (with sparing of the distal interphalangeal) associated with morning stiffness, depression, fatigue, and generalized myalgias. Pericarditis, myocarditis, pleural effusion, pneumonitis, and mononeuritis multiplex may occur. Synovial fluid is inflammatory. Treatment of an acute exacerbation involves immobilization, nonsteroidal anti-inflammatory drugs, and, occasionally, corticosteroids. Antimalarials, gold, and methotrexate are used for long-term therapy.

Bursitis refers to an inflammatory process involving any of the more than 150 bursae throughout the human body and may be caused by infection, trauma, rheumatologic diseases, or crystal deposition. Certain repetitive activities also may precipitate bursitis: “carpet layer's knee” (prepatellar bursitis) or “student's elbow” (olecranon bursitis). A suspicion for septic bursitis, especially in olecranon bursitis, necessitates aspiration of bursal fluid. Septic bursal fluid characteristically is purulent in appearance, with more than 1500 mm3 (mean 75,000, typically >30,000 leukocytes/mm3) and positive culture. Treatment principles include drainage, rest, compressive dressing, analgesics, and antibiotics for septic bursitis. Septic bursitis generally responds well to oral antibiotics, with emphasis on coverage of Staphylococcus (including MRSA) and Streptococcus species.