Symptomatic clasp-knife deformity of the spinous processes.
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Adult↗
Biomedical subjects
D Resnick
Publications and source records attributed to D Resnick.
Cloning and characterization of the Aeromonas caviae recA gene and construction of an A. caviae recA mutant.
A recombinant plasmid carrying the recA gene of Aeromonas caviae was isolated from an A. caviae genomic library by complementation of an Escherichia coli recA mutant. The plasmid restored resistance to both UV irradiation and to the DNA-damaging agent methyl methanesulfonate in the E. coli recA mutant strain. The cloned gene also restored recombination proficiency as measured by the formation of lac+ recombinants from duplicated mutant lacZ genes and by the ability to propagate a strain of phage lambda (red gam) that requires host recombination functions for growth. The approximate location of the recA gene on the cloned DNA fragment was determined by constructing deletions and by the insertion of Tn5, both of which abolished the ability of the recombinant plasmid to complement the E. coli recA strains. A. caviae recA::Tn5 was introduced into A. caviae by P1 transduction. The resulting A. caviae recA mutant strain was considerably more sensitive to UV light than was its parent. Southern hybridization analysis indicated that the A. caviae recA gene has diverged from the recA genes from a variety of gram-negative bacteria, including A. hydrophila and A. sobria. Maxicell labeling experiments revealed that the RecA protein of A. caviae had an Mr of about 39,400.
Aeromonas↗
Traction osteophytes of the lumbar spine: radiographic-pathologic correlation.
Previous reports have emphasized two types of osteophytes on the anterior aspects of the lumbar vertebral bodies: the common claw osteophyte and the less common but more significant traction osteophyte, which is indicative of spinal instability. To delineate the importance of the traction osteophyte, a radiographic-pathologic study was conducted. The results indicate that claw osteophytes are more frequent than traction osteophytes, that both may coexist in a single vertebral body, and that, in most cases, these osteophytes appear to represent different stages of the same pathologic process.
Humans↗
Infection versus tumor in the spine: criteria for distinction with CT.
To develop criteria to distinguish among pyogenic infection, nonpyogenic infection, and neoplastic processes in the spine by means of computed tomography (CT), the authors retrospectively analyzed 17 cases of pyogenic infection (20 sites), 40 cases of neoplastic disease (56 sites), and five cases of granulomatous infection (eight sites). Reliable criteria for pyogenic infection were complete prevertebral soft-tissue involvement, diffuse osteolytic destruction, gas within both bone and soft tissue, and a process centering on an intervertebral disk. Neoplastic disease was characterized by posterior element involvement, partial or absent prevertebral soft-tissue swelling, and osteoblastic alterations. In a limited number of cases, nonpyogenic infection was characterized by focal lytic bone involvement and marginal sclerosis. Blinded testing of these criteria indicated potential for improved diagnostic accuracy in clinical practice.
Humans↗
Patterns of femoral head migration in osteoarthritis of the hip: a reappraisal with CT and pathologic correlation.
Although medial, superior, and axial patterns of migration of the femoral head in osteoarthritis of the hip have been well described, it is not clear what anatomic and biomechanical factors determine the direction of migration. The authors studied 22 patients with bilateral (11 patients) or unilateral (11 patients) osteoarthritis by means of conventional radiography and computed tomography (CT) to define any relationships between migration in the coronal plane and that in the transverse plane and to determine whether femoral anteversion, acetabular anteversion, femoral neck-shaft angle, or acetabular inclination were related to particular migration patterns. Anterior migration was evident in 14 of the 19 hips with a superior migration pattern, whereas posterior migration was present in five of the seven hips with a medial migration pattern. In the remainder of cases, no migration in the transverse plane was present. Femoral anteversion as determined with CT, femoral neck-shaft angle, angle of acetabular inclination, and acetabular anteversion angle in this relatively small sample were all found to be within normal limits and appeared to have no influence on the occurrence of a specific pattern of femoral head migration.
Aged↗
Three-dimensional quantitative CT of the proximal femur: relationship to vertebral trabecular bone density in postmenopausal women.
Dual-photon absorptiometry (DPA) of the proximal femur cannot independently measure cortical and high-turnover cancellous bone. In this investigation, integrated cancellous, cortical, and total bone densities in the femoral neck and intertrochanteric region were measured bilaterally in 22 women aged 42-75 years. Contiguous section data were analyzed with two different protocols by means of three-dimensional histogram software. Single-section quantitative computed tomography (CT) was used to determine mean mineral equivalent values for vertebral cancellous bone from T-11 to L-3 in each woman. Significant correlation was found between cancellous bone density at the two sites, as well as between total femoral and vertebral measurements. Femoral cortical bone density was predicted less well by means of the vertebral cancellous data. Cortical, cancellous, and total proximal femoral density values tended to exhibit bilateral symmetry. Quantitative three-dimensional volumetric CT affords comprehensive evaluation of proximal femoral mineral status because of its capability for selective measurement of cortical, cancellous, and total bone density.
Absorptiometry, Photon↗
Rheumatoid arthritis: similarity of radiographic abnormalities in men and women.
To test the hypothesis that there are significant differences in the radiographic appearance of rheumatoid arthritis between men and women, the authors blindly evaluated bilateral hand and wrist radiographs in 32 men with definite rheumatoid arthritis and 32 age- and disease duration-matched women (mean age, 56.4 years; mean disease duration, 10.5 years). Radiographically, disease distribution and severity were identical in these matched groups. Superimposed osteoarthritis was frequent in both groups and related to age. Ill-defined bone proliferation was present in 13 of 64 hands in both groups. Cystic changes and well-defined erosions were present in 12 of 64 male hands and six of 64 female hands, but this difference was not statistically significant. In women, presence of cysts and bone proliferation was related to disease duration, whereas men exhibited these atypical features independent of disease duration. There was no statistically significant difference in the frequencies of typical and atypical features of rheumatoid arthritis between the two sexes, and the authors postulate that previously reported differences relate to patient selection and lack of adequate matching.
Arthritis, Rheumatoid↗
Peribursal fat plane of the shoulder: anatomic study and clinical experience.
A comprehensive anatomic and radiographic analysis of the peribursal fat plane in 12 cadavers confirmed that the fat plane seen on radiographs represents extrasynovial fat lining the subacromial bursa and documented the anatomic relations of the bursa. A three-part retrospective clinical evaluation of rotator cuff tears, calcific tendinitis, and rheumatoid arthritis was performed. Two osteoradiologists blindly graded the appearance of the peribursal fat plane with the shoulder in external versus internal rotation in 21 patients with arthrographically intact rotator cuffs and 21 patients with disrupted rotator cuffs. The peribursal fat plane was seen better with disrupted rotator cuffs. The peribursal fat plane was seen better with the shoulder in internal rotation and was seen in 60% of control subjects but only 21% of patients with rotator cuff tears. Partial or complete obliteration of this fat plane is a sensitive (79%) but less specific (60%) indicator of rotator cuff tears. Obliteration of the peribursal fat plane by inflammatory processes in adjacent tissues, including calcific tendinitis and rheumatoid arthritis, occurred with a high frequency.
Adipose Tissue↗
Rotator cuff disruption: diagnosis with digital arthrography.
Shoulder arthrography is a reliable technique for use in the diagnosis of tears of the rotator cuff, although delineation of the precise site and size of tears requires meticulous double-contrast technique and considerable examiner expertise. The authors initiated a prospective evaluation of digital arthrography of the glenohumeral joint in 28 patients with clinical manifestations suggesting rotator cuff tear because they believed that examination with this technique would allow more accurate definition of the precise status of the cuff. Fifteen patients had normal studies. Ten complete and three partial rotator cuff tears were demonstrated with digital technique, and the precise site of the tear was demonstrated in all of these cases. The results indicate that digital arthrography of the glenohumeral joint may have some advantages over standard arthrography in the delineation of complete and partial tears of the rotator cuff, particularly in defining the exact site of tears.
Adult↗
Subtalar and intertarsal joint involvement in hemophilia and juvenile chronic arthritis: frequency and diagnostic significance of radiographic abnormalities.
Because radiological distinction between hemophilia and juvenile chronic arthritis can be difficult, the ankle and foot radiographs of patients affected by these two disorders were evaluated to compare the frequency and pattern of joint involvement. No statistical difference was noted between the frequency of posterior subtalar joint involvement in the two disorders, but, in the juvenile chronic arthritis group, more than 90% of the abnormal posterior subtalar joints were associated with intertarsal involvement. This association was never found in patients with hemophilia. Isolated tibiotalar joint involvement without subtalar abnormalities was significantly more frequent in hemophilia than in juvenile chronic arthritis. Although clinical differentiation between the two disorders is easily made, intertarsal joint involvement could be a useful feature in the radiological distinction of hemophilia and juvenile chronic arthritis.
Adolescent↗
Isolated dislocation of the tarsal navicular: a case report.
Isolated dislocation of the tarsal navicular is a rare injury that is not mentioned in standard orthopedic textbooks and described only once in the English literature. Because of the rarity of this condition, the best means of treatment has not been established. A patient with this unusual dislocation was recently diagnosed and treated. Open reduction was eventually required, which was followed by the development of ischemic necrosis of the navicular.
Adult↗
Cross-sectional imaging of the capsular mechanism of the glenohumeral joint.
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Humans↗
Paget disease of bone: current status and a look back to 1943 and earlier.
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History, 20th Century↗
Spontaneous osteonecrosis of the tarsal navicular in adults: imaging findings.
We encountered five otherwise healthy adults with alterations of the tarsal navicular bone compatible with spontaneous osteonecrosis. Four women had bilateral involvement and one man had unilateral involvement. The patients were 23-71 years old. The disorder was initially described by Mueller and Weiss and should not be confused with Koehler disease (osteochondrosis of the tarsal navicular in children). This group of patients was compared with five other patients (29-74 years old) with similar radiographic and clinical changes in whom an underlying disease (rheumatoid arthritis, renal failure, trauma, and lupus erythematosus) associated with osteonecrosis was known. Routine radiography in both groups defined characteristic abnormalities of the navicular bone (decreased size, a comma-shaped configuration, increased radiodensity, fragmentation, and medial or medial and dorsal osseous protrusion). MR in three patients confirmed alterations consistent with osteonecrosis. Three of the patients without underlying disease had bilateral involvement on plain films, with flat feet and hindfoot valgus deformity, leading to local pain and deformity. In a fourth patient, bilateral distribution was documented by MR as marrow alterations. Although no certain pathogenic explanation for spontaneous osteonecrosis of the tarsal navicular is known, trauma and chronic stress changes caused by physiologic pressure on the medial longitudinal arch in hindfoot valgus and increased tension forces of the plantar aponeurosis during weight-bearing (in pes planus) may be important. Discrimination of primary from secondary osteonecrosis of the tarsal navicular bone is not possible by radiologic means alone, although bilateral distribution, particularly in women, favors the diagnosis of spontaneous disease.
Adult↗
Neuroarthropathy associated with chronic alcoholism.
Neuroarthropathy involving the feet is seen most commonly in patients with diabetes mellitus. Chronic alcoholism has been implicated as a cause of neuroarthropathy, but many alcoholics have coexistent diabetes mellitus, which may not be detected by measuring blood glucose levels alone. We report five chronic alcoholic patients with neuroarthropathic alterations of the feet in whom coexistent diabetes mellitus was excluded by using laboratory methods that are more sensitive than those employed in previously reported series of alcoholic neuroarthropathy. The radiographic features of neuroarthropathy in our five cases consisted of hypertrophic changes at the tarsal joints in four, bony fragmentation at the tarsal and metatarsal regions in three, fracture dislocation at the tarsometatarsal joint in two, and multiple pathologic fractures in one. We conclude that alcoholism can result in neuroarthropathy in the absence of diabetes mellitus.
Adult↗
Common disorders of synovium-lined joints: pathogenesis, imaging abnormalities, and complications.
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Arthrography↗
Radiologic manifestations of arthritides involving the foot.
This article has discussed the radiographic manifestations of several of the more common articular disorders affecting the foot. An organized, thoughtful approach to radiographic analysis in patients with articular diseases of the foot generally ensures accurate diagnosis. This approach requires knowledge of the classic morphologic features of each articular disease as well as its typical distribution in the foot. Using knowledge of radiologic-pathologic correlation and the target area approach to disease, the physician can make an accurate diagnosis in most instances.
Arthritis↗
Computed tomography of rheumatologic disorders. Part I.
The advent of computed tomographic (CT) scanning has initiated a revolutionary approach to the evaluation of articular disease. CT affords the opportunity to noninvasively evaluate both osseous and soft tissue structures during a single diagnostic examination. An optimal CT study demands proper technique, including a localization image, appropriate slice thickness and spacing, and window/level manipulation. The examination must be tailored to the specific indication for the study, which may include degenerative processes, inflammatory disease, or unexplained clinical symptomatology.
Humans↗