Search PubMed⌕ Search

Biomedical subjects

R Price

Publications and source records attributed to R Price.

At least 91 records · Page 5Linked to original sources
PubMed1993

Importance of bone resorption in the determination of bone density in women more than 10 years past the menopause.

There is general agreement that bone density falls with age and is higher in heavy people than light people. We have studied a variety of potential correlates of vertebral, ankle, and hip bone density to evaluate other potential influences on the skeleton. We recruited 196 healthy women who were more than 10 years past the menopause and collected a diet and activity record, a 24 h urine, and a fasting blood and urine specimen. These blood and urine samples were analyzed for factors related to calcium homeostasis. We then measured bone density at lumbar vertebrae 1-4 and the hip and the ankle bone density of the nondominant leg. Correlations between vertebral, hip, and ankle bone density and other measured variables were explored using the statistical package SPSS PC. At the vertebral site, in addition to correlations with age and body mass index (BMI), a negative correlation with a measure of bone resorption, the hydroxyproline creatinine ratio (OHPCR), was noted. At the ankle site, in addition to correlation with age, BMI, and OHPCR, a positive correlation with activity and a negative correlation with serum calcitriol were noted. At the hip site, as well as age, BMI, and OHPCR, significant correlations with GFR and dietary calcium intake were noted. These data suggest that even in women 10 years past the menopause bone resorption has a significant effect on bone density, that renal function may account for some of the variance in bone density at the hip, and that activity effects are more marked at sites of greater loading, namely the ankle.

Aged↗
PubMed1993

Screening for osteoporosis by bone densitometry: a stratified intervention approach.

We have performed computer modelling of the relationship between bone mass, age and hip fracture in a conditional probability model using a national population of 100,000 postmenopausal women aged 50 who have their bone density measured once. The computer model very closely reproduced the actual number of fractures in a Western Australian population. Intervention to bone loss completely in subjects with the lowest bone density (below 1 SD below the mean) would prevent 0.42 of a hip fracture per patient treated if the whole population were treated. Halving the rate of bone loss in the whole population would reduce hip fracture by two-thirds. These data suggest that hormone replacement therapy, which is the most effective therapy for preventing bone loss but which has the most side effects, should be focused on subjects with bone mass below 1 SD below the mean. The remainder of the population could be targeted with a public health campaign based on the lifestyle factors of increased dietary calcium and exercise which have been shown to slow but not stop bone loss.

Bone Density↗
PubMed1993

Comprehensive analysis of dynamic elastic response feet: Seattle Ankle/Lite Foot versus SACH foot.

This study evaluated biomechanical and metabolic performance differences between two prosthetic foot designs in light of their mechanical properties. Ten unilateral below-knee amputee subjects, at least 1 year after amputation, capable of walking and running, were studied. Differences in heel and forefoot compliance explained differences in gait events and alignment. Increased efficiency of pushoff in the Seattle Ankle/Lite Foot exists as evidenced by the decrease loading on the opposite limb during double support and a less shortened step length on the sound side compared to the SACH foot. The natural frequency of oscillation for the prosthetic feet was determined to be too high to provide energy storage and release synchronized with kinematic requirements because neither metabolic cost savings nor differences in metabolic efficiency were found. Comfortable walking speed and the nadir of metabolic rate and efficiency are not different. Via accelerometer measurement, it was found that the more compliant and lossy SACH foot heel was less likely to transmit high frequency vibration.

Adult↗
PubMed1993

Surgery for solitary thyroid nodules: assessment of methods to select patients at low risk for unsuspected malignancy in the unaffected lobe and the possible utility of preoperative thyroid ultrasound.

One hundred and twelve bilateral thyroidectomies for solitary thyroid nodules with suspected malignancy were performed. The incidence of malignancy in the 112 primary nodules was 42%. Twenty-nine of the 112 contralateral lobes (26%) contained malignancy, which was unsuspected in 80%. Of these 29, 20 were foci of papillary cancer < or = 5 mm and 9 were larger papillary tumors or follicular carcinoma. We analyzed these 112 patients to determine whether there was a simple method to identify those patients at risk for contralateral, unsuspected malignancy. With use of the AMES clinical staging retrospectively, 70 of the 112 patients were classified as having low-stage disease. Fifty percent (35) had cancers on the primary side and 27% (19) on the contralateral side. Of these 19 contralateral cancers, 14 were papillary cancers < or = 5 mm, 4 were papillary cancer > 5 mm and one was a 1.5 cm follicular carcinoma, a similar distribution as in the whole group of 112. When the AMES analysis then excluded those thought to be at risk for multicentricity or papillary carcinoma and examined female patients only with nonpapillary frozen sections, nonpapillary aspiration cytological results, and no history of radiation exposure, no further reduction in the proportion of contralateral cancers (7 of 26, 27%) was found. Fifty-five of the 112 patients underwent preoperative ultrasound scans. In those cases in whom the contralateral lobe had no intraoperative palpable or preoperative sonographic mass, 5 of 20 still had contralateral cancers, but all were papillary < or = 5 mm.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗
PubMed1993

The Seattle FICSIT/MoveIt study: the effect of exercise on gait and balance in older adults.

While exercise is generally recommended for older adults, the specific role of exercise in preventing falls and frail health is unclear. The Seattle FICSIT/MoveIt study is a population-based, randomized, controlled trial comparing the effects of three 6-month exercise interventions (endurance training, strength training, or combined endurance and strength training), and three 3-month endurance training interventions (stationary cycle, walking, or aerobic movement). Primary study outcomes are aerobic capacity, strength, gait, balance, and physical functional status. The study enrolls adults age 68-85 who have leg weakness and impaired gait. It differs from most previous community-based exercise studies in several respects: recruitment of subjects from a defined population; eligibility criteria based upon physiologic and functional status deficits; random assignment to exercise groups; assessment of both physiologic and functional status outcomes; follow-up beyond the completion of supervised exercise; and a large sample size (Total N = 180).

Accidental Falls↗
PubMed1993

A case of gonococcal mastitis in a male.

A case of a 42 year old homosexual man with mastitis of the left breast due to Neisseria gonorrhoeae is presented on account of its extreme rarity. It was probably acquired as a result of direct oral-nipple contact.

Adult↗
PubMed1993

Bone density after rigid plate fixation of tibial fractures. A dual-energy X-ray absorptiometry study.

We used dual-energy X-ray absorptiometry (DEXA) to measure the bone mineral content (BMC) of both tibiae in 13 patients who had been treated for a tibial fracture by rigid plate fixation. Within two weeks of plate removal the BMC was significantly greater in the bone that had been under the plate than at the same site in the control tibia. An unplated area of bone near the ankle showed a significant decrease in BMC at the time of plate removal with subsequent return to the level of the control tibia during the ensuing 18 months. We conclude that osteoinductive influences outweigh the potential causes of osteopenia, such as stress shielding and disuse, and that, contrary to expectation, demineralisation is not a factor in the diminished strength of the tibia after plating for fracture.

Absorptiometry, Photon↗
PubMed1993

Comprehensive analysis of energy storing prosthetic feet: Flex Foot and Seattle Foot Versus Standard SACH foot.

This study compared the mechanical and biomechanical functions, metabolic demand, and shock absorption of two dynamic elastic response (DER) prosthetic foot designs with the SACH foot. Nine individuals who had undergone unilateral below knee amputation were studied. Mechanical properties of the feet were related to gait biomechanics. Forefoot compliance is greatest for the Flex Foot and least for the SACH foot, hence, Flex Foot demonstrates (1) the longest midstance phase, (2) the greatest ankle angle range, and (3) greater forward movement of the center of pressure. There was some evidence that the DER feet produced a better push-off. However, neither the self-selected walking speed nor the metabolic rate or efficiency over a spectrum of walking speeds (73 to 120m/min) and running speeds (140 to 200m/min) was significantly different. Because no energy savings resulted for the DER feet, the release of stored energy in the flexible feet may not occur at the proper time to assist in ambulation as a result of the natural frequency of oscillation.

Adult↗
PubMed1993

Influence of cryotherapy on spasticity at the human ankle.

The application of cryotherapy to temporarily reduce spasticity is a widespread clinical practice. A method of quantifying spasticity, based on viscoelastic stiffness measurements at the ankle, was applied to objectively determine the efficacy of cryotherapy in reducing spasticity of the calf. Baseline, cryotherapy and one-hour postcryotherapy measurements of spasticity were performed in 25 subjects with clinical signs of spasticity secondary to traumatic brain injury, spinal cord injury, and stroke. A statistically significant reduction in spasticity occurred during cryotherapy. Postcryotherapy results were equivocal, although there was a tendency for diminished spasticity relative to the baseline measurement. Two subjects showed a clear aggravation of spasticity following cryotherapy, thus leading to the conclusion that dichotomous results are possible.

Adolescent↗
PubMed1992

Effect of lower limb on body propulsion.

The purpose of this study was to analyze and compare the effects of the leg during swing and stance phases of forward propulsion of the body for both men and women. Twelve able-bodied subjects, six men and six women, were studied with a Vicon(a) gait-analysis system. A two-dimensional, sagittal-plane biomechanical analysis featuring a link-segment model was used to determine the force at the hip in the horizontal direction. Integrating this force curve over time during the swing and stance gait phases produced linear impulses, representing swing and stance contributions to the propulsion of the body, and it allowed quantitative comparisons using student t and Fisher tests. The deceleration of the swing leg was found to be the major contributor to the forward propulsion of the body. The stance leg initially exerted the major restraining or negative impulse during early stance; then it generated a positive impulse during push-off in late stance. A typical pattern of gait impulses was defined for normal gait. Male and female gait impulses were not significantly different for all gait phases.

Adult↗
PubMed1991

Local injection treatment of tennis elbow--hydrocortisone, triamcinolone and lignocaine compared.

Corticosteroid injections are the mainstay of treating tennis elbow even though their effectiveness has not been well established by controlled studies. A survey of consultant rheumatologists confirmed a widespread preference for this treatment but they varied in their choice of steroid dose and preparation. We examined the value of some practices by comparing local injections of 2 ml 1% lignocaine with either 10 mg triamcinolone or 25 mg hydrocortisone made up to 2 ml with 1% lignocaine (Study 1). The investigation was conducted double blind. Within the first 8 weeks, pain relief was greater for triamcinolone than hydrocortisone although the differences were not statistically significant. The response to both steroid preparations was significantly better than for lignocaine up to this point but at 24 weeks, the degrees of improvement were similar for all three groups and many patients still had pain. Relapse was common. In a separate but similarly designed study, triamcinolone 10 mg was compared with 20 mg of the same agent. Improvements of pain were similar and followed the same time scale. Post-injection worsening of pain occurred in approximately half of all steroid treated patients in both studies and this was sometimes severe and persistent. It was less frequent amongst those given lignocaine alone. Skin atrophy was reported in all groups but was more frequent amongst those given triamcinolone in Study 1. In conclusion, more rapid relief of symptoms was achieved with 10 mg triamcinolone than with 25 mg hydrocortisone or lignocaine alone and there was less needed to repeat injections. Results obtained with 20 mg triamcinolone were similar to those of the smaller dose.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Quantitative measurement of spasticity in children with cerebral palsy.

Spasticity was quantified in nine children with spastic diplegia, using a sinusoidal displacement of the foot at frequencies from 3 to 12Hz. Ankle-joint stiffness was separated into elastic (energy-storing) and viscous (energy-dissipating) components. 'Path length' was used to represent the variation in stiffness over this frequency range. Compared with 11 unaffected children, a significant difference in path lengths was demonstrated for the children with spasticity. An age-dependent effect was demonstrated when path lengths of unaffected children were compared with those of 10 unaffected adults. A modified path-length measure is proposed which minimizes age dependency, yet enables detection of spasticity. Passive stiffness properties of unaffected adults showed higher elastic stiffness, viscosity and friction than unaffected children. A method was developed to evade the need for temporary nerve blocks to calculate inerital properties of the foot in persons with spasticity.

Biomechanical Phenomena↗