Articles on Medical Diseases and Conditions

Entries for the ‘Bone, Joint, and Collagen-Vascular Disorders’ Category

Radionuclide Bone Scanning

Certain disorders affecting bone are discussed elsewhere (hyperparathyroidism, metastatic tumor in bone). The commonest diagnostic problems involve fractures, osteomyelitis, and metastatic tumor. The nonradiologic procedures most frequently used in bone disease are serum alkaline phosphatase and bone scanning. Strontium 85 was the first agent to be widely used in bone scanning. Its relatively high patient […]

Radionuclide Joint Scanning

Besides synovial fluid examination, radionuclide joint scanning is a procedure that may offer useful information. For screening purposes, the scan could be performed with one of the isotope-labeled phosphate compounds used for bone scanning. These scans reveal abnormality in most joints that have a significant degree of inflammation, even when subclinical. Joint scanning permits a […]

Synovial Fluid Analysis

When synovial fluid is aspirated, 1 ml or more should be placed into a sterile tube for possible culture and a similar quantity into a heparinized tube for cell count. The remainder can be used for other procedures. A cell count is performed on anticoagulated fluid using 0.9% saline as the WBC pipette diluent (the […]

Other Conditions Associated with Arthritis

Arthritis and arthralgia may be present in 4%-23% of patients with primary biliary cirrhosis. One report indicates that many more have radiologic abnormalities of erosive arthritis but have no symptoms. About 50% of patients with hemochromatosis and about 25% of patients with chronic active hepatitis develop arthritis or arthralgias; up to 40% of patients with […]

Septic Arthritis

Septic arthritis is most often monoarticular but may affect more than one joint. Bacteria responsible for joint infection vary with age group, similar to the organisms producing meningitis. Haemophilus influenzae, Staphylococcus aureus, and gram-negative bacteria predominate in early childhood; S. aureus, pneumococci, and streptococci in later childhood; and S. aureus, pneumococci, streptococci, and gonococci in […]


Pseudogout is caused by calcium pyrophosphate crystal deposition. It clinically resembles gout to some degree but tends to affect large joints such as the knee rather than small peripheral joints. Joint x-ray films indicate some differences from classic gout but are frequently not a sufficient basis for diagnosis. Synovial fluid examination discloses calcium pyrophosphate crystals, […]

Arthritis due to Crystal Deposition (Crystalline Arthropathies)

Gout usually involves single specific joints, usually including some of the small joints of the extremities. The most typical location is the metatarsal-phalangeal joint of the great toe, which is affected in about 75% of patients. The knee and ankle are involved in about 50% of patients. One third or more of patients have more […]

Tests for Increase or Decrease in Bone Mass

Increased bone turnover occurs during normal preadult growth; destruction of bone from accidental, metabolic, or neoplastic causes; and as an effect of certain medications. For many years skeletal x-ray was the only clinical method used to detect bone change. Unfortunately, significant change could not be seen until about 50% of bone density was lost. Later, […]

Idiopathic Inflammatory Myopathies

The category of idiopathic inflammatory myopathies includes several entities involving progressive muscle weakness due to muscle inflammation of known etiology, primarily involving proximal muscles with a typically symmetrical distribution. There are elevated levels of various muscle-associated enzymes such as creatine kinase (CK), certain electromyographic abnormalities, and microscopic chronic inflammatory infiltrate in the affected muscle. Because […]

Circulating Immune Complexes

Immune complexes involve the binding of antigen to specific antibody and form part of the normal host response to foreign antigens. In some cases, immune complexes apparently can be deposited in tissues or organs and produce tissue injury. Blood vessels are most frequently involved. Although immune complexes may involve IgG, IgA, or IgM antibody, immunoglobulin […]