Gen Niwayama

Radiographic and Pathologic Features of Spinal Involvement in Diffuse Idiopathic Skeletal Hyperostosis (DISH)

The vertebral involvement of DISH is described from an evaluation of 215 cadaveric spines and 100 patients with the disease. Radiographic features include linear new bone formation along the anterolateral aspect of the thoracic spine, a bumpy contour, subjacent radiolucency, and irregular and pointed bony excrescences at the superior and inferior vertebral margins in the cervical and lumbar regions. Pathologic features include focal and diffuse calcification and ossification in the anterior longitudinal ligament, paraspinal connective tissue, and annulus fibrosis, degeneration in the peripheral annulus fibrosis fibers, L-T-, and Y-shaped anterolateral extensions of fibrous tissue, hypervascularity, chronic inflammatory cellular infiltration, and periosteal new bone formation on the anterior surface of the vertebral bodies.

Clinical, Radiographic and Pathologic Abnormalities in Calcium Pyrophosphate Dihydrate Deposition Disease (CPPD): Pseudogout

Clinical, radiographic and pathologic abnormalities in calcium pyrophosphate dihydrate deposition disease (CPPD) (pseudogout) are outlined in an investigation of 85 patients with definite or probable disease and available cadaveric and human surgical material. Pyrophosphate arthropathy produced distinctive roentgenographic abnormalities with were most frequent in the knee, wrist and metacarpophalangeal joints. Although the alterations superficially resembled osteoarthritis, they were frequently more severe and progressive with extensive fragmentation of bone, causing intra-articular osseous bodies. Pyrophosphate arthropathy occurred in unusual locations, such as the radiocarpal compartment of the wrist, elbow, and patellofemoral compartment of the knee. These characteristics allow the radiologist to suggest a probable diagnosis of CPPD even in the absence of articular calcification.

Calcaneal abnormalities in articular disorders. Rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis, and Reiter syndrome.

The calcaneus of normal control patients, and those with rheumatoid arthritis, ankylosing spondylitis, psoriasis, and Reiter syndrome was studied. Pathological abnormalities of the plantar aponeurosis, Achilles tendon, and retrocalcaneal bursa account for the radiographic alterations. In normal individuals, lateral radiographs show the thickness of the Achilles tendon to be not greater than 8 mm; the retrocalcaneal bursa creates a radiolucency which extends at least 2 mm below the superior surface of the calcaneus. In patients with any of these 4 articular disorders, Achilles tendinitis produces thickening of the tendon, and retrocalcaneal bursitis obliterates the normal radiolucency.

Degenerative Disease of the Sacroiliac Joint

Analysis of 46 sacroiliac joints removed in toto at random during routine autopsies was undertaken to define the pathologic and radiographic alterations of this joint in middle-aged and elderly patients. Each joint was sectioned, photographed and radiographed and large microscopic slides were prepared. Sacroiliac osteoarthrosis resulted in progressive cartilage degeneration, particularly on the ilial side of the joint, with eventual cartilaginous fusion. Para-articular bony ankylosis was produced by bridging osteophytes on the anterior and inferior surfaces. Sacroiliac intra-articular bony ankylosis was confined to cadavers with ankylosing spondylitis. In some patients radiographic differentiation of osteoarthrosis and ankylosing spondylitis may require tomography.

Subchondral Resorption of Bone in Renal Osteodystrophy

In a radiographic-pathologic study of the spine and several axial joints in a cadaver with renal osteodystrophy, subchondral resorption of bone is described as an important mechanism of osseous abnormality. Widening and irregularity of the sacroilliac and sternoclavicular joints and symphysis pubis are related predominantly to trabecular destruction beneath cartilage surfaces, substitutive fibrosis, and new bone formation. Subperiosteal abnormalities at these locations produce juxta-articular erosions. The presence of osteitis fibrosa cystica about multiple Schmorls nodes within the thoracic vertebral bodies suggests that subchondral resorption beneath the cartilage end-plates of the spine may be associated with disk protrusions and represents one further example of hyperparathyroid joint disease.

Intra-articular calcification in scleroderma.

Two patients with scleroderma demonstrated intra-articular calcification, which is rarely observed in this disease. The authors suggest that intra-articular calcification and erosion of adjacent cartilage and bone are related.

Bilateral pulmonary hilar lymphadenopathy. An unusual manifestation of metastatic renal cell carcinoma.

Four patients with bilateral pulmonary hilar adenopathy secondary to lymphangitic spread from renal cell carcinoma were examined. Two additional cases had adenopathy secondary to nasopharyngeal carcinoma. Patients may initially present with bilateral pulmonary lymphadenopathy or as late as 3 1/2 years after the discovery of the primary renal tumor. The mechanism of lymphangitic spread probably is related to reflux of tumor emboli from the thoracic duct into the bronchomediastinal trunks because of incompetent lymphatic valves. In one case gallium imaging demonstrated bilateral hilar isotopic uptake as well as periaortic uptake.

Resorption of the undersurface of the distal clavicle in rheumatoid arthritis.

An elongated erosion on the undersurface of the distal clavicle, adjacent to the coracoid process, may be seen in the shoulder of a patient with rheumatoid arthritis. This finding is apparently related to inflammatory changes in the coracoclavicular ligament. Such an erosion may occur with or without additional radiographic alterations and, although not entirely specific, suggests rheumatoid arthritis.

The plantar compartments of the foot: a roentgen approach I. Experimental observations.

The integrity of the plantar muscle compartments of the human foot were studied utilizing radiographic and anatomic techniques in an attempt to determine potential pathways for spread of soft tissue infection. One of three major plantar muscle compartments--medial, intermediate or lateral--in 24 unembalmed cadaveric feet was injected percutaneously under fluoroscopy with radiopaque Methyl-methacrylate using both manual and automatic injection techniques with pressure callibration. Following freezing, specimens were sectioned, radiographed, and dissected or partially macerated. Frequency and patterns of extravasation of contrast material were documented and recorded. The results obtained support the concepts that: a) there are three distinct plantar muscle compartments that are maintained by intermuscular septae; and b) there are potential communicating pathways provided by specific anatomic structures.