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Biomedical subjects

J Aronson

Publications and source records attributed to J Aronson.

At least 73 records · Page 4Linked to original sources
PubMed1992

Cavitary osteomyelitis treated by fragmentary cortical bone transportation.

Fragmentary cortical bone transportation can be used to fill large gaps in chronic cavitary osteomyelitis when standard techniques have failed. A low-energy corticotomy can create a loose fragment of cortex with periosteal attachments and surface blood supply still intact. This "vital" fragment can be gradually pulled across a defect within a bone to restore the integrity of the bone segment by distraction osteogenesis. The biologic principles for successful distraction osteogenesis by this innovative technique are illustrated in a 41-year-old man with chronic cavitary (150 cc) (four years) osteomyelitis refractory to multiple debridements, Papineau grafting, gentamicin beads, and tricalcium phosphate.

Adult↗
PubMed1992

Mechanical considerations in using tensioned wires in a transosseous external fixation system.

Factors that affect wire tension were examined using external mechanical testing units as well as in-line load cells. The circular external fixator with wires supported at each end exhibits a self-stiffening effect such that wire stiffness increases with wire deflection. Mechanical slippage between wire and fixation bolt is the primary reason for loss of wire tension. Slippage can be avoided by adequate torque on the fixation nut (20 N.m). Guidelines are presented for proper and safe tensioning techniques to achieve clinically indicated tensions without risk of breakage.

Bone Wires↗
PubMed1992

Efficiency of the bone scan for occult limping toddlers.

Fifty consecutive occult limping toddlers were prospectively evaluated by acute triphase 99mTc MDP scintigraphy (TTS) at Arkansas Children's Hospital from 1984 through 1989. Only patients with a limp that could not be diagnosed by an orthopaedist were included. TTS proved essential in localizing the lesion in 27 patients (54%). With only two false negatives and one false positive, this test was shown to be highly sensitive, specific, efficient, and predictive, especially as compared with temperature, white blood cell (WBC) count, erythrocyte sedimentation rate (ESR), and plain radiography. Because no infections were missed by TTS, patients with a normal TTS could be safely observed as outpatients, saving thousands of health care dollars in this small series.

Arthritis, Infectious↗
PubMed1991

Ultrasound in advanced pediatric osteomyelitis. A report of 5 cases.

The use and reporting of ultrasound for the evaluation of pediatric osteomyelitis is minimal. However, ultrasound is noninvasive and does not employ ionizing radiation, and it is less expensive than other methods available. Consequently, its application, if contributory, would be desirable in evaluating pediatric osteomyelitis. We examined five patients ranging from 2-weeks to ten-years-old with ultrasound after bony abnormalities were found on plain film. In all cases ultrasound was valuable in assessing the type and location of abnormality (4 cases of osteomyelitis, 1 case of discitis), but unhelpful in determining the age of disease.

Child↗
PubMed1991

Osteomyelitis in children with sickle cell disease: early diagnosis with contrast-enhanced CT.

Two children with sickle cell disease and osteomyelitis were treated. In one child, definitive treatment was delayed until computed tomography (CT) revealed a subperiosteal abscess. Early performance of CT in the other child resulted in prompt diagnosis and treatment. Before the appearance of the characteristic plain radiographic findings, diagnosis of osteomyelitis in patients with sickle cell disease can be difficult because the clinical manifestations of infarction and osteomyelitis can be similar. Radionuclide scans have yielded mixed results. In equivocal cases, early performance of CT can help establish the diagnosis of osteomyelitis to avoid significant morbidity.

Abscess↗
PubMed1991

The prevalence and extent of vibration sensitivity impairment in men with chronic ethanol abuse.

We have studied vibration sensitivity impairment in 100 male alcoholic veterans and 52 control subjects who had no etiologic factors for peripheral neuropathy. Vibration sensitivity was quantitated at the hallux with the Vibration Sensitivity Tester. Alcoholic subjects had impairment of vibration sensitivity when compared with control subjects (p less than .001). This difference persisted when a covariance analysis was performed which included age (coefficient +/- SE: 1.40 +/- 0.35 units, p less than .001). Asymptomatic subjects also had vibration sensitivity impairment (p less than .01). In subjects whose ages were greater than or equal to 45 years, 47% of the alcoholics had poorer vibration sensitivity than did any of the controls. Among the alcoholic subjects there were significant correlations of the vibration perception threshold with both age (r = 0.39, p less than .001) and drinking duration (r = 0.35, p less than .001). In multiple regression analyses these associations remained significant (p less than .05). These data indicate that vibration sensitivity impairment is highly prevalent in alcoholic subjects and that impairment may even occur in those who are asymptomatic.

Adult↗
PubMed1991

Radiologic evaluation of limb-lengthening procedures.

Limb-lengthening procedures are being performed at an increasing rate in the United States. A successful outcome relies heavily on serial radiologic evaluation. Therefore, it is important for radiologists to become familiar with the various techniques, their normal radiologic appearance, and associated complications. Lengthening by the Wagner method, distraction epiphysiolysis, and the Ilizarov technique are illustrated. Chondrodiatasis and callotasis also are discussed.

Bone Lengthening↗
PubMed1990

Preliminary studies of mineralization during distraction osteogenesis.

Distraction osteogenesis by the Ilizarov method was performed on 20 dogs. Mineralization at the site of the left tibial metaphyseal lengthening was measured by weekly quantitative computer tomography (QCT) using the contralateral tibia as a control. Four dogs each were killed on Days 7, 14, 21, and 28 of distraction in order to correlate QCT with microradiology, nondecalcified histology, quantitative calcium analysis, and scanning electron microscopy. It was consistently found that intramembranous ossification proceeded centripetally from each corticotomy surface toward the central fibrous interzone. Bone columns crystallized along longitudinally oriented collagen bundles, expanding circumferentially to surrounding bundles. As the distraction gap increased, the bone columns increased in length and in diameter, while the fibrous interzone remained about 4 mm long. Histologically, the bone columns resembled stalagmites and stalactites, as seen by microradiography and scanning electron microscopy, that projected from each corticotomy surface toward the center. These cones reached maximum diameters of 150-200 mu at the corticotomy surfaces. Radiodensity (QCT) increased gradually from the central fibrous interzone toward each corticotomy surface. Mineral density, as determined by calcium quantification, reflected the microscopic geometry and radiographic polarity.

Animals↗
PubMed1989

High-resolution hip ultrasound in the limping child.

Hip ultrasound was performed on 44 children (114 exams) presenting with a painful hip or a limp thought to be due to hip disease. Effusions were found in 20 patients (21 hips). Hip ultrasound in combination with aspiration of the joint was found to be useful in diagnosis of osteomyelitis and septic joints, transient synovitis, trauma, and traumatic synovitis. We had no false positives or false negatives for hip effusions by ultrasound. In previous reports, absolute measurements have been relied upon for determination of hip effusions. We present a characteristic appearance of a capsule with and without abnormal joints fluid. The results of these 44 patients are summarized.

Arthritis, Infectious↗
PubMed1989

Local bone transportation for treatment of intercalary defects by the Ilizarov technique. Biomechanical and clinical considerations.

Ilizarov applied revolutionary methods for salvaging limbs with severe congenital, posttraumatic, or other acquired deformities. His methods, which use a universal system of ring external fixators with tensioned transosseous wires, were developed over the past 35 years at his institute in Kurgan, USSR. These noninvasive techniques have proved successful in over 300,000 patients (adults and children) treated for bone shortening and intercalary deficiency, angulatory and rotational malalignment, active infection, ischemia, joint contractures, and nonunions. Bone transportation involves moving a free segment of living bone to fill intercalary bone defects with vital bone. The trailing end of the transport bone segment maintains continuity with the host bone surface by distraction osteogenesis. The leading end of the transport bone segment fuses to the target bone surface by transformational osteogenesis. The small diameter of the transosseous wires contributes to better patient tolerance over the prolonged treatment times required for gradual distraction at 1 mm per day.

Biomechanical Phenomena↗
PubMed1989

The histology of distraction osteogenesis using different external fixators.

The local biology of distraction osteogenesis using Ilizarov and Wagner external fixators was compared in unilateral tibial lengthenings in two groups of eight dogs. Serial roentgenograms with histological correlation revealed some basic similarities as well as distinct differences between the two groups. All dogs fully bridged the experimental gap by intramembranous ossification. Subtle histological changes in the alignment of collagen bundles and subsequent ossification reflected the mechanical configuration of each fixator. The multiplanar, full-pin Ilizarov system delivered concentric load to the site of osteogenesis, inducing perfectly parallel columns of new bone. The uniplanar, one-half pin Wagner system induced angulation of the collagen and subsequent bone columns on the basis of eccentric load to the osteogenic interface. Despite a significant difference in axial rigidity, the Ilizarov and Wagner external fixators induced osteogenesis of equal volume.

Animals↗
PubMed1988

Quality of life after the trauma center.

During a 2-year period, 445 trauma patients were transported directly from the scene by helicopter to a trauma center. The Glasgow Outcome Scale and a work status scale were used to evaluate followup information gathered 6 months to 2 1/2 years after the incident. Findings were cross-tabulated with Injury Severity Score (ISS) categories. Seventy-two per cent of the patients had an ISS greater than 15. The overall mortality was 26.1%. Twenty-seven patients (6.1%) were lost to followup. Eighty-three per cent of the patients made a good recovery and 75% returned to their former work status (job, school, or household duties). Of the followed survivors, 5.6% had severe disability and 2.0% were permanently institutionalized. No one remained in permanent vegetative state after 6 months. In a second followup period (3 to 4 years after incident) half of the patients contacted who were not working during the first followup period had either returned to their former work status or were currently trying to reenter the work force. Most survivors of serious injury benefit from an integrated trauma system as measured by their good recovery and the ability to return to work. Few patients remain severely disabled or vegetative, requiring permanent institutionalization.

Adolescent↗
PubMed1988

A protocol of plain radiographs, hip ultrasound, and triple phase bone scans in the evaluation of the painful pediatric hip.

A useful protocol for the evaluation of hip pain in the pediatric patient, using a combination of plain radiographs, hip ultrasound (US), and triple phase radionuclide bone scans is presented. Patients with hip pain were initially evaluated by plain radiographs of the pelvis and hips. If no diagnosis was reached, the hips were studied for effusions by real-time hip ultrasonography. If an effusion was present, the joint was aspirated for diagnosis. If no effusion was present by US or if no diagnosis was reached by aspiration, triple phase radionuclide bone scans were performed. Fifty patients were evaluated by this prospective protocol, and the diagnosis was reached in 48 of the 50 cases (10 by plain radiographs, 16 by US, and aspiration of the joint, and 22 by triple phase bone scans). Hip effusions were found in 20 patients by US, with no false positives or false negatives. Previous studies for detecting effusions by US have emphasized absolute measurements of the capsular width, but we report a typical appearance of the hip capsule when fluid is present (a bulging convex capsule). When no effusion is present, the capsule is concave and parallels the long axis of the femoral neck.

Child↗
PubMed1987

Dorsal defect of the patella and infection.

Lesions of the patella are relatively rare, although a large variety of etiologies have been reported. To our knowledge this is only the second reported case of a Brodie's abscess of the patella. Its radiologic appearance was identical to that described for the common dorsal defect of the patella.

Abscess↗