Biomedical subjects
D Resnick
Publications and source records attributed to D Resnick.
Diagnostic imaging of tarsal and metatarsal stress fractures. Part II.
As the preoccupation with physical fitness grows in this country, the problem of "stress fracture" has become more clinically significant. Reliable techniques for imaging the musculoskeletal system have also continued to grow, allowing the clinician to better diagnose and manage this condition. However, the radiographic findings of stress fracture are sometimes difficult to interpret. This review compares plain radiography, scintigraphy, CT, and MRI in the imaging of stress fractures.
Pathogenesis of discovertebral and manubriosternal joint abnormalities in rheumatoid arthritis: a cadaveric study.
The precise pathogenesis of discovertebral lesions in rheumatoid arthritis has long been debated with the emergence of 2 conflicting theories: discovertebral extension of synovial inflammation from a neighboring articulation (Luschka, costovertebral joint) and repetitive discal trauma with Schmorl's nodes. In order to address this controversy, we performed a radiographic-pathologic correlation of a rheumatoid cadaver and compared the alterations seen in the cervical and lumbar discovertebral junction; we further included an evaluation of the manubriosternal joint, another cartilaginous articulation. Our data confirmed that advanced discovertebral lesions in the cervical and lumbar spine are related primarily to endplate failure that itself is caused by apophyseal joint destruction and segmental spinal instability, although inflammatory rheumatoid lesions of the cervical intervertebral discs probably arising from the Luschka joints are also evident. Conversely, the lesions of the manubriosternal joint were produced by inflammatory changes related to the development of a synovial cavity in the articulation.
Multiple stress fractures in the hindfoot in rheumatoid arthritis.
A case of nontraumatic bilateral multiple stress fractures of the hindfoot in a 60-year-old white man with rheumatoid arthritis (RA) is described. Review of the literature indicates that stress fractures of the calcaneus and other bones of the hindfoot are an unusual complication of RA and have not been reported previously. Factors leading to the development of stress fractures in the patient with RA are discussed.
Conventional tomography in musculoskeletal trauma.
Conventional tomography utilizes controlled blurring of overlying structures, in effect, to remove these possible obscuring overlying structures and permit improved evaluation of anatomic detail within the specific layer or focal plane of interest. Although it has largely been replaced by true sectional imaging modalities such as CT and MR imaging, it remains a valuable tool in specific settings as in musculoskeletal trauma. It is particularly useful when the orientation of the pathology requires coronal or sagittal planes for optimal evaluation.
Sternocostal joints. Anatomic, radiographic and pathologic features in adult cadavers.
Using radiographic-pathologic correlation, we studied the sternocostal joints derived from 27 consecutive cadavers and one additional cadaver with rheumatoid arthritis. Radiographic findings that were tabulated included joint space narrowing, sternal or costal osteophytes, articular calcification, vacuum phenomena, and the degree of ossification of the costal cartilages. The first sternocostal joint could be classified as either a synchondrosis or synostosis in every instance; however, a joint cavity lateral to the first sternocostal joint represented a normal variation and was seen radiographically in 10 specimens. The second sternocostal joint was synovial in type and intimately related to the manubriosternal joint; cavitation within this joint was present bilaterally in 36% of our specimens. Degenerative changes in the sternocostal articulations were characterized much more frequently by sternal osteophytes than by costal osteophytes or joint space narrowing. Calcification compatible with chondrocalcinosis was observed in two cadavers. Radiographic and pathologic evidence of synovial inflammation was evident in the sternocostal joints of the rheumatoid specimen.
Why the need for LAL testing in water treatment?
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Computed tomography with multiplanar reformation and three-dimensional image reconstruction in the preoperative evaluation of adult hip disease.
Computed tomography (CT) with multiplanar reformation and three-dimensional (3D) image reconstruction was used pre-operatively to outline the bony morphological changes and femoral-acetabular relationships in 25 adult patients suffering from hip disease. Diagnoses included ischaemic necrosis of the femoral head, osteoarthritis, rheumatoid arthritis, calcium pyrophosphate dihydrate (CPPD) crystal deposition disease, previous trauma and chronic dislocation. Polyethylene models of the femora and acetabula were constructed from three-dimensional contouring of CT data and compared with resected specimens in patients subjected to subsequent total hip arthroplasty. Information provided by this imaging technique was useful in both selecting and guiding the most appropriate surgical procedure and it was found that models depicted the actual bony contours with reasonable accuracy. CT combined with multiplanar reformation and 3D analysis may be the optimal pre-operative means of assessment of the diseased adult hip.
Destructive spondyloarthropathy in hemodialysis patients. Report of four cases and prospective study.
A destructive spondyloarthropathy is reported in four patients undergoing maintenance hemodialysis for chronic renal disease. In a separate investigation a controlled, prospective radiographic study of the cervical spine revealed this spondyloarthropathy in 4 (15%) of 26 long-term dialysis patients. A single disc level was involved in three patients, and two disc levels were involved in one patient. This spondyloarthropathy correlated with the duration of dialysis but not with the radiographic evidence of renal osteodystrophy or severity of laboratory abnormalities associated with hyperparathyroidism. Three of these four patients also had discovertebral erosions or destruction involving the lumbar spine. Cervical spine flexion views revealed evidence of ligamentous laxity or instability in three (12%) dialysis patients, all with vertebral resorption and disc space narrowing. It is postulated that this instability may contribute to the development of cervical discovertebral lesions or be a secondary manifestation of disc destruction.
New radiographic technique may renew credibility of bone densitometry.
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Radiologic and pathologic patterns of end-plate-based vertebral sclerosis.
Degenerative spondyloarthropathy is the result of a number of related pathologic processes, including loss of disc elasticity, repetitive mild trauma, and osteoporosis. The effects are manifested microscopically in a number of patterns reflecting alterations in stress, healing microfractures, and bone-cartilage interactions along the vertebral end-plate. The microscopic changes lead in turn to radiographically evident vertebral body sclerosis. The resultant sclerosis is not always in the classic band-like pattern along the vertebral end-plate, and the atypical patterns may be difficult to recognize as degenerative in origin. In a detailed analysis of clinical and postmortem material, we have categorized both the pathologic and radiographic patterns of benign non-Pagetic vertebral body sclerosis. This radiographic classification provides a unified framework for clinical recognition of the various patterns of degenerative sclerosis.
Chronic unreduced dislocations of the glenohumeral joint: imaging strategy and pathologic correlation.
Although the evaluation of acute or recurrent dislocations of the glenohumeral joint (GHJ) using routine radiography, specialized views, arthrography, and computed tomography (CT) has been extensively studied, methods of evaluation and osseous pathology of chronic unreduced GHJ dislocations are not well documented. In order to define such methods and pathology, we studied nine patients with chronic (greater than 6 months) unreduced anterior, posterior, superior, or central dislocations as well as one patient with a chronic rotator cuff injury; and seven scapular specimens, six with matching humeral specimens, with osseous abnormalities similar to those in the patients. We examined 15 additional scapular specimens with evidence of subluxation secondary to chronic rotator cuff injury. Standard, reformatted, and three-dimensional (3D) CT techniques were used to evaluate both the patients and the specimens. Our results indicate that characteristic alterations occur in the scapula and humeral head that are far more extensive than the classic Hill-Sachs, Bankart, and trough lesions. Such alterations occur at sites of osseous contact between the malpositioned humerus and scapula and are modified owing to prolonged adjustments made by the patients in an attempt to increase GHJ motion. Although routine radiography and specialized views are of some value, standard and 3D CT provide a more accurate analysis of the location and extent of the bone abnormalities and, as such, should be employed, particularly in the evaluation of patients in whom surgery is being considered.
Unilateral lower extremity hypertrophic osteoarthropathy associated with aortic graft infection.
We have reported a case of unilateral lower extremity hypertrophic osteoarthropathy (HOA) associated with vascular graft infection, and have reviewed previous reports of this association. Knowledge of this association may lead to earlier diagnosis of graft infection in patients with clinical evidence of HOA.
Extruded nucleus pulposus causing osseous erosion of a lumbar vertebral body. A report of three cases.
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Symptomatic clasp-knife deformity of the spinous processes.
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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.
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.
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.