On the difference in the mode of ossification of the first and other metacarpal and metatarsal bones / by Allen Thomson.

  • Thomson, Allen, 1809-1884.
Date:
[1868?]
Catalogue details

Licence: Public Domain Mark

Credit: On the difference in the mode of ossification of the first and other metacarpal and metatarsal bones / by Allen Thomson. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

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    13G seven or eight years, and in some more advanced, I have found, in addition to the more distinct and constant jiroximal epiphyses of the first metacarpal and metatarsal bones, traces of a separate distal epiphysis. In figure 1 and figure 3, a view is given of the appearances presented by the first and second metacarpal and metatarsal bones with their corresponding digits in the mace- rated and dried condition at the age of eight years. The fis- sures indicated at d', though deep, are not here such as to separate completely the epiphyses from the shaft of the bones, higures 2 and 4 show the state of the parts in recent wet specimens taken from a subject stated to be about a year younger than the first. The section of the bones has been car- ried longitudinally from the dorsal to the palmar surface; and it will be observed that in the first metatarsal bone the di.stal epiphysis, in wdiich ossification has made considerable advance, is completely separated from the o.ssified shaft of the bone by a plate of cartilage; and that, though somewhat irregular, the form of the epiphysis is very similar to the more constant epi- physis of tlie second metatarsal bone. In the first metacarpal boue the separating plate of cartilage is not complete, leaving a space in the centre where the bone of the shaft is continuous with that of the end portion, but yet sufficient to indicate the form of an epiphysis. In figure 2' I and figure 4' I are represented the appear- ances observed in another specimen in the wet state; and in these it wdll be seen that, while the ossification from the main shaft has run onwards in the greater and deeper part into that of the end of the bones, the surrounding parts are interrujjted by the indentation of small angular pieces of cartilage which mark the commencements, as it were, or lowest stage in the separation of an epiphysis, and correspond in every re.spect to the outer part of the more complete dividing cartilage. Such observations as these are necessarily limited from the difficulty of obtaining subjects at a suitable age : but from the circumstance that in all favourable instances which have come under my notice at ages between seven and fifteen years, traces of the separation of the distal epiphysis have been found in