TL;DR: In rats of 40, 49 and 59 days of age the positions of the femoral and tibial nutrient foramina were determined by direct measurement, using a travelling microscope, and bone remodelling in the vicinity of the canal is not necessary.
Abstract: In rats of 40, 49 and 59 days of age the positions of the femoral and tibial nutrient foramina were determined by direct measurement, using a travelling microscope. The femoral nutrient foramen remained constant in position with increasing age, whereas the tibial nutrient foramen moved relatively nearer to the distal end of the shaft. In the case of the femur this can be accounted for entirely by differences in growth rates at the epiphyseal plates of the femur compensating for the disproportion in the distances of the foramen from the two plates. In the tibia, however, extension of the extremely oblique nutrient canal as the bone increases in girth is also involved. Bone remodelling in the vicinity of the canal is not necessary to explain the results.
TL;DR: It is emphasised that the medullary arterial system, fed by principal nutrient, metaphysial and epiphysial arteries, is the mechanism for the delivery of arterial blood to long bones, and that the arteries of bone extremities are of overwhelming importance in the nutrition of the long bone as a whole.
Abstract: 1. The principal nutrient canal of the femur in day-old rabbits was occluded and subsequent femoral growth observed. 2. An initial shortening is followed by equalisation and a final absolute shortening of the order of 3 per cent in occluded femora as compared with controls. 3. It is emphasised that the medullary arterial system, fed by principal nutrient, metaphysial and epiphysial arteries, is the mechanism for the delivery of arterial blood to long bones, and that the arteries of bone extremities are of overwhelming importance in the nutrition of the long bone as a whole.
TL;DR: A 55-year-old man with a history of backache was found on roentgen examination to have osteolytic changes in the lumbar spine, sacrum, and right ilium, with enlargement of the nutrient canal of the...
Abstract: A 55-year-old man with a history of backache was found on roentgen examination to have osteolytic changes in the lumbar spine, sacrum, and right ilium, with enlargement of the nutrient canal of the...
TL;DR: Three features in the long bones, shown by radiograms, have been used as markers for the study of bone growth, and both ends of tibia and fibula showed very high frequency of suitable lines for markers.
Abstract: Three features in the long bones, shown by radiograms, have been used as markers for the study of bone growth.
(I)
Transverse lines of arrested growth. Radiograms of six long limb bones from 1,576 individuals were investigated for clearness and persistence of these lines. Both ends of tibia and fibula showed very high frequency of suitable lines for markers, possibly also the distal end of femur and radius.
(II)
Notches in the base of second and fifth metacarpal bones. Measurements of growth from apex of the basal notch to the ends of the shaft were performed on serial hand radiograms. The proportion of growth from distal and basal ends averaged 87:13 in the second and 80:20 in the fifth metacarpal bones.
(III)
Nutrient canals. The initial point of ossification was determined by a prolongation of the nutrient canal intersecting the central axis of the medullary cavity. The proportion of growth from that point to distal and basal ends of the shaft averaged 68:32 and 64:36 for the second and the fifth metacarpal bones, respectively. These values are significantly different from the measurements obtained from the notches.