Biomedical subjects
Publications and source records attributed to G Hooper.
Blood flow was measured in the calcaneal tendons of rabbits using the techniques of labelled microsphere uptake and 133Xe washout simultaneously. There was no correlation between the results obtained with the two methods in individual animals. It is doubtful if the assumptions underlying the 133Xe washout technique are valid when it is used to measure blood flow in tendons.
Single-passage experiments in which bone-seeking tracers are injected arterially at the same time as microspheres to determine an extraction ratio are only valid if the maximum transit time through bone is less than the minimum recirculation time. This validity was investigated by injecting various intravascular and more diffusible tracers into the hearts or aortas of rats and rabbits at different times before the rapid cessation of circulation. At no time between 4 and 60 s after injection did the bone concentration of any of the tracers fall to negligible values. Removal of unbound tracer is therefore not complete before recirculation starts, and the single-passage technique is invalid. Measurements of bone blood flow based on the clearance of 18F cannot be substantiated, as its extraction is flow dependent.
Several laboratories, including our own, have investigated the physiology of bone blood flow by perfusion of the tibia via the nutrient artery. Any damage caused to the nerve supply by cannulation of the artery might affect the results. The possible effect of such damage was investigated by measuring blood flow to the dog tibia using a microsphere technique, before and after sympathectomy. No effect was found and the tibial nutrient artery is therefore a suitable vessel for perfusion when estimating nutrient exchange in bone.
Blood flow in intact tendons in dogs was measured using 57Co-labelled microspheres and compared with the simultaneous clearance of a diffusible radionuclide, 85Sr, by the same tendons. Clearance was significantly greater than flow in all tendons, indicating that diffusion from surrounding tissues may be important in the nutrition of normal tendons.
Deep flexor tendons from the forepaws of rabbits were removed and cut into two segments, sutured and freeze-dried. About one week later each tendon was placed in a knee joint of the same rabbit from which the tendon had been removed. At one, two, three and six weeks the tendons were retrieved and examined grossly, histologically and by electron microscopy. For comparison a control group using non freeze-dried tendons was also studied. Although there was evidence of central necrosis, superficial healing of the freeze-dried tendons occurred and was presumably due to cells from the synovial fluid.
A child with bilateral congenital synostoses of the little and ring finger metacarpal bones is described. The resulting abduction deformities of the little fingers were corrected by metacarpal osteotomies.
This paper discusses the use of nitrofurazone in the treatment, or prophylaxis, of wound infection, various pyodermas and second and third degree burns, as well as its prophylactic use in skin grafting and donor sites. The literature is reviewed over three decades.
Two cases of congenital pseudarthrosis of the ulna due to neurofibromatosis are reported. Similar radiographic changes in the ulna were found, with distortion of the capitulum and part of the trochlea and bowing of the radius. In one patient the head of the radius was dislocated and in the other it dislocated readily during pronation. A possible mechanism to explain the findings was suggested. On the basis of these and a review of the literature it is recommended that the main aim of treatment should be maintenance of the normal relative lengths of the radius and ulna by early excision of the pseudarthrosis to remove the restraining effect of the abnormal ulna. This will allow normal development of the lower end of the humerus and radius and prevent dislocation of the radial head.
We have reviewed 106 fractures of the tibia with an intact fibula. Most patients were treated in above-knee plaster casts and allowed to walk. Only 2 fractures failed to unite and there were 4 refractures. In 27 patients (25 per cent) the fracture healed with more than 5 degrees of varus angulation. The cause of this deformity and its prevention are discussed.
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The gene Wh, causing anophthalmia in the Syrian hamster, Mesocricetus auratus, is a highly pleiotropic gene, which has profound effects upon eye development, pigmentation, and reproduction. Since male hamsters homozygous for this gene are usually sterile, the objective of this study was to determine whether the testes of mutant hamsters differed from the normal phenotype. Accordingly, the testicular tissue from ten normal, ten heterozygous, and ten homozygous mutant animals in the AN/As-Wh strain were compared at the gross, light, and electron microscopic level. Testicular tissue from several mutant animals approached the normal phenotype, due to variable expression of the gene. However, most testes from homozygous mutant hamsters were hypoplastic and aspermic. Abnormalities were observed in Leydig cells, Sertoli cells, and in the developing germ cells. Seminiferous tubules contained germinal epithelium arrested in the early spermatid stage of spermiogenesis, possibly due to premature failure of the Golgi apparatus and subsequent dysgenesis of the acrosome. Since the primary action of the gene is unknown, it was postulated that the gene either acts directly to alter pituitary function, or that the abnormalities in reproduction are due to a failure of eye development and subsequent lack of function of the visual pathway.
We report an anomalous muscle belly of the flexor digitorum superficialis acting on the right index finger. The median nerve lay superficial to the muscle in the forearm and at the wrist.
The incidence of congenital dislocation of the hip in 156 children with infantile idiopathic scoliosis was 6.4 per cent, approximately 10 times its frequency in the general population. In both of these deformities there was a predominance of girls (eight girls: two boys). In unilateral dislocation of the hip the convexity of the thoracic scoliosis was on the same side as the dislocation. Eight out of the 10 children with both deformities also had plagiocephaly.
There was a history of hemiplegia due to stroke in 97 (6.5 per cent) of 1483 consecutive patients with fresh fractures of the neck of the femur. Both cervical and trochanteric features occurred significantly more often on the hemiplegic side. Internal fixation was technically satisfactory in trochanteric fractures, but failed frequently in cervical fractures.
We report a patient with stenosing tenovaginitis affecting the sheath of the tendon of extensor digiti minimi. The similarities to typical de Quervain's disease are discussed.
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Explore the source record for details and available documents.
Explore the source record for details and available documents.