Biomedical subjects

M Brookes

Publications and source records attributed to M Brookes.

At least 37 records · Page 2Linked to original sources

PubMed1990

Head injuries in accident and emergency departments. How different are children from adults?

STUDY OBJECTIVE: The aim of the study was to examine the differences between child and adult patients attending accident and emergency departments after recent head injuries. DESIGN AND SETTING: A retrospective survey based on existing case records from 23 Scottish accident and emergency departments for 1985 was compared with prospective data from one hospital over 9 months in 1984. PATIENTS: 3838 children under 15 and 4775 adults attended hospital with head injuries during the period analysed. MAIN RESULTS: Only 9% of children and 20% of adults had evidence of brain damage (altered consciousness on arrival, or history of altered consciousness with amnesia on arrival). Scalp lacerations were recorded in approximately 40% of both children and adults, more commonly in those without brain damage. Fewer children than adults had a skull x ray; in both age groups x rays were more often done if there was evidence of brain damage, headache, or vomiting, and less often when there was a scalp laceration. Only 11% of children were admitted compared with 20% of adults. Admission rates per 100,000 population per year were 4011 for children and 1473 for adults (1967 overall); admission rates for brain damage were 290 for children and 341 for adults (331 overall). CONCLUSIONS: These are the first population based estimates of frequency of head injuries presenting at accident and emergency departments, analysed by age, gender and cause of injury. They should be of value when planning services for the head injured.

Adolescent↗

PubMed1990

The vascular repair of an experimental osteotomy held in an external fixator.

The vascular repair of a lower tibial transverse osteotomy in the New Zealand white rabbit held in an external fixator was studied in three groups. In the first group, composed of 18 animals, the osteotomy gap was maintained throughout repair. Three animals were killed every two weeks up to 12 weeks postoperatively. In the second group, composed of three animals killed at six weeks, the fragments were brought into contact. In a third and similar group, the osteotomy was compressed. Plain roentgenograms were taken weekly, and intraarterial perfusion with Micropaque was performed when the animals were killed. Roentgenography using fine-grain film, microradiography, and histology were carried out on a midsagittal tibial slice. The results showed that following transverse osteotomy in which the gap was maintained, vascular union of the proximal and distal cortices and associated external callus masses had usually occurred by ten weeks postoperatively. However, an occasional hypovascular zone at the osteotomy site at 12 weeks was associated with fibrous delayed union. In contrast, when apposition or compression of the fragments was used, repair was accelerated, and cortical bone union was established at six weeks. Vascular union of the fragments occurred predominantly through the medullary vessels. The results emphasize the overriding clinical importance of abolition of a fracture gap to achieve rapid revascularization of a fracture and its union by bone.

Angiography↗

PubMed1988

Avascular necrosis and the blood supply of the femoral head.

Postmortem femoral artery perfusion revealed abnormalities in the femoral head pattern of vessels in steroid-treated renal transplant patients as compared with controls. Degenerative changes were found in some of the arteries and arterioles of the hip capsule and femoral head in the renal transplant patients. Two of these patients' femoral heads showed microfocal avascular necrosis. Although high-dose steroids were used in these patients, none had suffered clinically from hip disease while alive. These findings suggest the possibility that local arterial disease may be involved in the pathogenesis of avascular necrosis.

Adult↗

PubMed1983

Stimulation of bone repair by ultrasound.

The repair of fibular fractures has been accelerated and modified by treatment with ultrasound. Complete bilateral transverse fibular fractures were made in adult female Wistar rats. Twelve were maintained as untreated controls. In seventy rats, one fracture was treated with ultrasound and the other mock-irradiated. Ultrasound was delivered at an intensity of 0.5 W cm-2 (spatial average, temporal peak), pulsed 2 ms on, 8 ms off for 5 minutes on 4 consecutive days during each week of treatment. The effects of treatment for different combinations of weeks, and at frequencies of 1.5 MHz and 3.0 MHz, were compared microradiographically and histologically. Ultrasonic therapy was most effective when given during the first two weeks after injury, that is, during the inflammatory and early proliferative phases of healing (before hard callus formation). Bone repair tended to be of the juvenile type, involving rapid ossification with little cartilage production when treatment was limited to this period.

Animals↗

PubMed1979

Studies of skeletal tracer kinetics: II. evaluation of a five-compartment model of [18F]fluoride kinetics in rats.

We have evaluated a five-compartment model of [18F]fluoride kinetics in rats. The initial fluoride distribution was found to be similar to that of [77Br]bromide, a known extracellular-fluid (ECF) tracer, in agreement with the hypothesis underlying the model, and the measured uptake rate in rat bones compared well with the digital computer solution. Simpler models did not give a better fit. In dead rats, fluoride movement was found within the skeleton, presumably from bone ECF to bone substance, although not as rapidly as predicted or found in the live animal. Evaluation of the rate constants permitted estimates to be made of cardiac output, skeletal blood flow, and bone ECF volume, all in accord with independent measurements. It is suggested that skeletal blood flow at rest is a constant fraction of body weight, and probably subserves a hematopoietic as well as a mineralization function.

Animals↗

PubMed1975

Circulatory depression in bone after acrylic implantation.

Because of the continuing hazard of post-operative sepsis in joint replacement surgery and the possibility that persistent bone ischemia may be a contributing factor, it is desirable to know the hemodynamic consequences in bone of the implantation of orthopedic acrylic cement. Experiments were carried out on 60 rats. In 30, a bore-hole was made, unilaterally, in the tibia. In another 30, a bore-hole was made in the tibia and a small amount of polymethylmethacrylate cement (Surgical Simplex P) was implanted into the marrow cavity through the bore-hole. By means of 51-Cr labeled red cells and 59-Fe labeled resin particles, the blood volume and blood flow rate in the tibiae were calculated simultaneously as a percentage of the values in the contralateral tibiae. The results showed that at 14 days and 112 days postoperatively, both blood volume and flow were significantly depressed in tibiae in which acrylic cement had been implanted, as compared with tibiae in which only a bore-hole had been made. It was concluded that orthopedic cement implanted into bone renders the bone hypovascular.

Animals↗

PubMed1975