This investigation was supported by research grants HD 00377 from the National Institute of Child Health and Human Development and AM 6705 from the National Institute of Arthritis and Metabolic Diseases of the National Institutes of Health, Public Health Service.
The prenatal development of the human humerus†
Version of Record online: 3 FEB 2005
Copyright © 1969 Wiley-Liss, Inc.
American Journal of Anatomy
Volume 124, Issue 4, pages 431–445, April 1969
How to Cite
Gray, D. J. and Gardner, E. (1969), The prenatal development of the human humerus. Am. J. Anat., 124: 431–445. doi: 10.1002/aja.1001240403
- Issue online: 3 FEB 2005
- Version of Record online: 3 FEB 2005
Forty pairs of humeri, from a series of embryos and fetuses ranging from 26 to 342 mm in crown-rump length, were measured, radiographed, and sectioned for microscopic study.
A primary bony collar was present before the end of the embryonic period, and in a 27 mm embryo it extended for nearly one-third of the length of the humerus. Erosion of the collar occurred at the end of the embryonic period. By about 37 mm, endochondral ossification began, and cartilage canals were invading the proximal epiphysis.
As endochondral ossification proceeded proximally and distally and growth zones became established, periosteal bone formation also proceeded longitudinally and, until about 18 weeks, extended about one millimeter beyond the zone of cartilage destruction in the growth zones. Subsequently the extents of periosteal and endochondral ossification were the same and at term occupied 79% of the length of the humerus.
Trabeculation of the bony collar began in the embryonic period. Fusion of endochondral trabeculae with the inner aspect of the periosteal shell began by 61 mm. A central marrow cavity free of trabeculae was consistently present after 86 mm. Evidence of reconstruction appeared in the proximal end by 73 mm and in the distal end by 113 mm, and was always present after 97 and 125 mm respectively.