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Biomedical subjects

J B Williamson

Publications and source records attributed to J B Williamson.

At least 37 records · Page 2Linked to original sources
PubMed1994

The osteogenic potential of rib autografts can be preserved in culture.

STUDY DESIGN: This was an experimental study to compare various methods of storing rib autograft between stages of spinal surgery. OBJECTIVE: The authors' goal was to determine the optimum conditions for storing bone graft, while preserving its osteogenic potential. SUMMARY OF BACKGROUND DATA: It never has been demonstrated that osteoblastic function can be preserved after bone graft is stored. Other researchers have shown preservation of cellular function, but not its nature. METHODS: Excised rib was stored in one of several ways: in culture medium at -196 C, 4 C, or 37 C, or in saline at 4 C for 2 weeks and then cultured at 37 C. Any cells produced were characterized using standard techniques. RESULTS: Bone stored at 37 C and -196 C retained its osteogenic potential. Bone stored at 4 C in saline did not. Bone stored at 4 C in culture medium was intermediate in its preservation of osteogenic capacity. CONCLUSIONS: Bone stored under suitable conditions retains osteogenic potential, and when reimplanted will add osteogenic cells to the fusion mass.

Adolescent↗
PubMed1993

The generational equity debate: a progressive framing of a conservative issue.

This article discusses the generational equity debate in the United States--including its origins and the functions it serves. This debate has emerged in the context of concerns over the aging of the population, budgetary crises, growing health care costs, increased poverty among children, growing economic inequality, and declining faith in institutions. By potentially fragmenting support for Social Security and other social programs, the generational equity approach to framing public policy issues may serve the interests of those conservatives wishing to shrink and restructure the American approach to social welfare. However, the possibility exists that this debate could serve also as a forum to advance progressive ideas about universal access for persons of all ages to income and health benefits and employment opportunities.

Adult↗
PubMed1991

Percutaneous stimulation of the cauda equina. A new diagnostic method in spinal stenosis.

A study to determine the feasibility of measurement of conduction velocities through the lumbosacral nerve roots by direct percutaneous stimulation of the cauda equina is reported. The technique was applied to a series of normal volunteers and its reliability and reproducibility confirmed. An electrophysiologic defect was demonstrated in most patients with surgically proven lateral recess stenosis. Electrophysiologic recovery was shown in patients examined after surgery. Although the technique can be refined, these early results are encouraging.

Cauda Equina↗
PubMed1990

Outcome after acute osteomyelitis in preterm infants.

Eight cases of skeletal infection in preterm infants were studied. All the infants were systemically unwell, with polymorpholeucocytosis. Diagnosis was by blood culture, and any radiographic changes were apparent at the time of presentation. Infection was often multifocal, with sites around the knee being most commonly affected. Staphylococcus aureus was the pathogen isolated in six of the eight cases; in these treatment with fusidic acid was effective and well tolerated, even at doses that were less than the recommended therapeutic minimum. Even with prompt diagnosis and aggressive treatment orthopaedic sequelae are common.

Acute Disease↗
PubMed1988

Pressure distribution in the wrist joint.

We performed a study to determine pressure distribution properties of the normal radio-carpal joint. A system was developed for measurement of the contact pressure within the wrist joint surfaces. The transducer was based on Fuji pressure-sensitive paper, which was inserted into the joint space through a dorsal capsular incision. The hand was then positioned using a jig that permitted free axial loading of the joint. Each of five specimens was tested in 36 positions combining flexion/extension with radio/ulnar deviation and supination/pronation. The transducers were analyzed for contact area, scapho-lunate contact area ratio, pressure, and centroid locations using a microcomputer-based video-imaging system. The scaphoid and lunate contact areas on the radius and triangular fibrocartilage were separate and distinct in all wrist positions. Together these contact areas accounted for a relatively small fraction of the total joint surface area (average contact area/total joint area = 0.206, SD = 0.0495). For an applied 103 Newton compressive load, the high pressure averaged 3.17 MPa (SD = 0.83 MPa). Overall, the scaphoid contact area was 1.47 times that of the lunate, although variations occurred with position, as in flexion, in which the scaphoid/lunate area ratio was 0.83. The high-pressure centroids of both scaphoid and lunate contact areas shifted palmarly from 20 degrees of flexion to 20 degrees of extension and then dorsally with further extension. The scaphoid-lunate intercentroid distance averaged 14.91 mm with a range of 10-20 mm.

Carpal Bones↗
PubMed1988

Old age dependency in historical perspective.

In recent years much has been written about old age dependency and the need for greater emphasis on individual and familial responsibility for supporting elderly persons as opposed to state responsibility. We argue that old age dependency is not a new problem and that there was communal responsibility--as opposed to strictly privitized responsibility--for elderly persons in the past.

Aged↗
PubMed1987

Load transfer characteristics of the wrist. Part I. The normal joint.

A static positioning frame allows the positioning of unembalmed human upper extremities in any combination of wrist flexion/extension, radio/ulnar deviation, and pronation/supination. Pressure-sensitive film (Fuji) was used to study the contact areas, scaphoid-lunate area ratios, average high pressures, centroid positions, and intercentroid distances of five wrist joints under a uniform load of 103 Newtons (N) in 36 different positions. The contact areas accounted for only 20.6% of the available joint surface. They shift from a primarily palmar location to a primarily dorsal location when the wrist changes from flexion to extension. Overall the scaphoid contact area was 1.47 times that of the lunate and was generally greatest with the wrist in ulnar deviation. The scapho-lunate contact area ratio increased as wrist position changed from radial to ulnar deviation and/or from flexion to extension. For the constant load of 103 Newtons the high pressure averaged 3.17 megapascals (MPa). The scaphoid and lunate high pressure centroids shifted palmar when wrist position changed from 20 degrees of flexion to 20 degrees of extension and then shifted dorsal with further extension of the wrist. The intercentroid distance averaged 14.91 mm and ranged from 10 to 20 mm.

Biomechanical Phenomena↗
PubMed1987

Load transfer characteristics of the wrist. Part II. Perilunate instability.

An experimental model with a static positioning frame, pressure-sensitive film (Fuji), and a microcomputer-based video digitizing system, previously developed by the two senior authors, was used in this study to examine the effects of increasing perilunate instability on the load transfer characteristics of the wrist. These effects included a significant dorsal ulnar shift of the scaphoid centroid with increasing perilunate instability together with a less dramatic palmar ulnar shift of the lunate centroid. Overall, the scaphoid contact area was found to decrease as the stage of perilunate instability increased, even in ulnar deviation and/or extension, which in the normal wrist was found to be the positions that had the greatest scaphoid contact area. Average pressures in the high pressure zones were found to significantly increase in wrists with a stage III instability compared with normal wrists. An increase in the intercentroid (scaphoid/lunate) distance was most evident with the wrist in 20 degrees extension, neutral radioulnar deviation, and 90 degrees supination.

Biomechanical Phenomena↗
PubMed1986

Ultrasound in the treatment of ankle sprains.

Ultrasound is commonly used in association with other forms of treatment in the management of sprains of the lateral ligament of the ankle. Despite its widespread use there is little scientific evidence to support its role in the management of sprained ankles. We have conducted a prospective, randomized, double-blind trial to compare the results of physiotherapy for sprains of the lateral ligament of the ankle without the use of ultrasound with physiotherapy which included ultrasound. The results in the 154 patients who entered the trial demonstrate that there was no significant difference between the results achieved by the group treated with ultrasound and by those managed without.

Adolescent↗
PubMed1985

The Reagan-era shift toward restrictiveness in old age policy in historical perspective.

For forty years following the passage of the Social Security Act, the United States experienced a liberalization in public policy toward the aged. In the late 1970's, the momentum of this liberalization began to ebb, and by the early 1980's, a shift toward greater restrictiveness was underway. Scholars and journalists often discuss this Reagan-era shift as if it were a unique policy initiative. A case can be made, however, that this is just a recent example of a recurrent pattern of social policy reform and reaction in the history of American politics. This point is illustrated by placing the current policy shift alongside a historically remote period.

Aged↗
PubMed1982

Humanizing nursing home environments: the relevance of hospice principles.

At the heart of the rapidly growing American hospice movement is a philosophy of care that emphasizes patient individuality and responsiveness to total needs of the dying and their families. To date, the response to this model of terminal care has been favorable. The hospice is viewed as a humanizing mode of health care with a capacity to enhance the quality of life experienced by persons defined as terminal. Data gleaned from participant observation in an American hospice program by one of the authors supports this view. The hospice has the potential to provide a social context for humane, personalized death in which maximum effort can be made to control pain in all its forms: physical, psychological, social, and spiritual. Sociological literature has been much harsher in its assessment of the quality of life in nursing homes. Such discussions frequently include references to nursing home environments as fostering loss of autonomy and social death. This paper suggests that the hospice approach to care of the dying includes several elements that can be utilized to improve the quality of life in nursing homes: a total needs emphasis, increased patient autonomy, open discussion of death, a community ideology, a team orientation that cuts across levels of staff hierarchy, a role blurring of caregivers, focus on patients and families as the unit of care, and mutually beneficial integration of hospice with the outside community. There are, however, crucial differences between a hospice and a nursing home which may hamper direct transference of humanizing hospice principles, e.g., hospice patients are defined as terminal; staff, thus, can be motivated to put forth their best because of perceived time limits. There are also important differences in the characteristics of patient populations, length of stay, economic constraints, ability to attract volunteers, and emphasis on task-orientation. The time has come to apply increased ingenuity to a adapting humanizing hospice principles to the care of elderly in nursing homes.

Attitude of Health Personnel↗
PubMed1981

Drug and alcohol dependency services: prepaid group launches vanguard program.

How can a medical community best approach a person who has developed alcohol or drug dependency? And to what extent can recovering drug dependent people truly help others? This article concerns what is happening at an alcohol- and drug-dependency center at one prepaid AGPA member group, where they are looking at these problems, particularly poignant ones, since the program is akin to the type of program in which the federal government has expressed increasing interest. In fact, on November 7, 1980, the Health Care Financing Administration announced the availability of grant funds for demonstration projects (Federal Register, pp. 74456-61) on the effectiveness of providing alcoholism services under Medicare and Medicaid programs "in free-standing residential and outpatient centers and halfway houses utilizing non-physician personnel."

Alcoholism↗