Chondral fractures of the knee. Arthrographic, arthroscopic, and clinical manifestations.

Chondral fractures are a distinct clinical entity and should be distinguished from the more frequently recognized osteochondral fracture. They occur most often in the medial femoral condyle of young adults following a rotational injury or direct blow to the knee. Clinically, the chondral fracture mimics a torn meniscus and may or may not be associated with a meniscal tear. Unlike osteochondral fractures, chondral fractures exhibit no specific abnormalities on routine radiography, necessitating arthroscopy or arthrography for diagnosis. The abnormality is seen as as a scooped-out defect or linear fracture in the articular cartilage on arthrography; on arthroscopy the findings are similar, though the fracture may appear stellate in cases of a direct blow to the knee.

Clinical manifestations of synovial cysts.

Although synovial cysts are most commonly associated with rheumatoid arthritis and osteoarthritis, they may occur in many other conditions. The clinical manifestations of these cysts are numerous and may result from pressure, dissection or acute rupture. Vascular phenomena occur when popliteal cysts compress vessels, and result in venous stasis with subsequent lower extremity edema or thrombophlebitis. Rarely, popliteal cysts may cause arterial compromise with intermittent claudication. Neurological sequelae include pain, paresthesia, sensory loss, and muscle weakness or atrophy. When synovial cysts occur as mass lesions they may mimic popliteal aneurysms or hematomas, adenopathy, tumors or even inguinal hernias. Cutaneous joint fistulas, septic arthritis or osteomyelitis, and spinal cord and bladder compression are examples of other infrequent complications. Awareness of the heterogeneous manifestations of synovial cysts may enable clinicians to avoid unnecessary diagnostic studies and delay in appropriate management. Arthrography remains the definitive diagnostic procedure of choice, although ultrasound testing may be useful.

Chronic arthritis of rabbits induced by mycoplasmas. I. Clinical microbiologic, and histologic features.

Mycoplasma arthritidis and Mycoplasma pulmonis induced chronic arthritis in rabbits on intraarticular injection, characterized by joint swelling and histologic evidence of chronic active inflammation persisting at least one year. Cartilage and bone destruction was a prominent late feature of M arthritidis but not M pulmonis disease. Despite the progressive nature of the disease and persistence of active inflammation for many months after inoculation, mycoplasmas and mycoplasma antigens were not found in joint tissues after 7 weeks.

Radiography, radionuclide imaging, and arthrography in the evaluation of total hip and knee replacement.

Twenty patients with 21 total joint replacements including 17 hips and 4 knees were studied by plain film radiography, radionuclide imaging, and subtraction arthrography to evaluate these procedures for assessing prosthetic complications. Surgery was performed in 14 patients and confirmed loosening of 8 femoral and 7 acetabular hip prosthesis components and 1 femoral and 4 tibial knee prosthesis components. Plain films suggested loosening of only 9 hip components and no knee components. In contrast, radionuclide imaging and subtraction arthrography were considerably more effective in demonstrating loosening as well as other causes of the painful total joint prosthesis.

Fractures of the thoracolumbar spine in ankylosing spondylitis.

Fractures through the disc or juxta-end plate region of the vertebra as well as the posterior elements have been observed in the thoracic and lumbar spine in ankylosing spondylitis. These are usually associated with increasing pain, usually do not produce neurologic deficit, and may require orthopedic fixation to heal. Irregularity and sclerosis at the margins secondary to pseudarthrosis may develop and should not be confused with a pyogenic or granulomatous infection. Biomechanically these fractures resemble the "seat belt type" or Chance fracture probably because of shifting of the axis of flexion and extension in the ankylosed spine away from its normal location in the center of the nucleus pulposus.

Autosomal dominant osteosclerosis.

Two cases of a craniotubular hyperostosis are presented. The radiographic features closely resemble Van Buchem disease (hyperostosis corticalis generalisata; endosteal hyperostosis, recessive type), including symmetrical and bilateral diaphyseal cortical thickening of the long and short tubular bones as well as sclerosis and thickening of the calvaria, mandible, shoulder and pelvic girdles, and thoracic cage. Unlike Van Buchem disease, no periosteal excresences are observed, alkaline phosphatase is normal, no basal foramina encroachment of the skull is present, and the genetic pattern is dominant inheritance. These cases possibly represent a separate disorder rather than a variant of Van Buchem disease.

Septic arthritis: a complication of rheumatoid arthritis.

Eighteen cases of long-standing rheumatoid arthritis and superimposed pyarthrosis were reviewed to determine the most distinguishing radiographic features. Soft-tissue changes allowed earlier diagnosis in the knee and ankle joints and consisted of large asymmetrical joint effusion and fat-pad edema. Bony articular changes were more helpful than soft-tissue changes in the wrist and hip because of the paucity of adjacent extracapsular fat and were associated with delayed radiographic recognition of superimposed pyarthrosis. These changes are presumptive evidence of complicating septic arthritis and their presence necessitates needle aspiration and culture of the joint for proper definitive treatment.

Radiology of knee joint replacement.

As total knee replacement becomes more successful due to advances in surgery and bioengineering, a greater number of patients will be offered this procedure as a viable alternative to arthrodesis. Radiologic consultation will be sought for evaluation of proper alignment as well as postoperative complications such as loosening, instability, dislocation, limitation of range of motion, fracture, and infection. This evaluation may be accomplished by plain films and arthrography. Radiographic aspects of these features are discussed and illustrated.

Arthrography in total hip prosthesis complications.

Previous reports have stressed the value of hip arthrography primarily in determining the presence of loosening of the total hip prosthesis. Although loosening is a common complication and frequently associated with infection, other complications producing a painful hip prosthesis exist and are demonstrable by arthrography. Since the etiologies of these are as diversely different as the treatment, the hip arthrogram is advocated as an integral part of the diagnostic approach to the patient with a painful hip prosthesis in order to assess the specific complication and determine the therapeutic approach.