The first metacarpal is the thumb first phalange: EvoDevo implications / El primer metacarpiano es la primera falange del pulgar: implicaciones en EvoDevo

We examined the status of the first metacarpal bone whose shape, fetal and post-natal development correspond to those of the thumb proximal phalanx. Galen already described this, circa 170 CE. Our radiographic data confirm that the pre-axial (radial or anterior) side of the hand matures, later than the post-axial (ulnar or posterior) side, both, pre- and post-natally. A new perspective on thumb primate and human ontogeny is discussed and comparative observations on the Evolutionary Development (EvoDevo) of the thumb and the first toe are proposed along with a nomenclature honoring Galen's original roposition.

Se analiza el estado del primer metacarpiano cuya forma y desarrollo embrionario, fetal y postnatal corresponde a los de la primera falange del pulgar. Galeno notó que éste era la primera falange del pulgar cerca de 170 DC. Esto no es un simple cambio de nomenclatura, ya que da una nueva luz a los problemas evolutivos de ontogenia (EvoDevo). Nuestros datos radiográficos confirman que el lado radial (anterior o pre-axial) de la mano madura, pre y post-natalmente, mas tardíamente que el lado cubital (posterior o post-axial). Se discuten nuevas perspectivas sobre la ontogenia y filogenia humana y de primates, y se proponen estudios comparativos del desarrollo del pulgar y del ortejo mayor.

Study on development of hand-wrist bone in 14 year-old adolescents I: bone age standard for boys / 法医学杂志

OBJECTIVE@#To study the bone development in adolescents in China, and establish forensic skeletal age standard for estimation of the criminal responsible age in 14 years old male adolescents.@*METHODS@#One hundred and three healthy boys aged from 13 years and 9 months to 14 years and 3 months in Lengshuijiang, Hunan, China were enrolled in this study. X-ray films of their left hand-wrist were taken dorsaventrally, and 15 selected sites on the wrist X-ray films were examined and measured under standard condition. The development grade was confirmed by maximum percentage to establish a method to estimate the bone age, which was then checked by single blind method.@*RESULTS@#Development grade of the first metacarpal bone and the first phalanx IV was partially closed (less than 1/3), but the rest was non-closed. The cross diameters of all the osteoepiphysis were wider than that of all the diaphysis. The development grade of the fourth metacarpal bone and the fifth metacarpal bone as well as the adjacent third phalanx were different in both younger age group (<14 years, mostly non-closed) and the older age group (>14 years, mostly closed). The confirmed accuracy (in 30 boys) was 80%.@*CONCLUSION@#Our study seems to be feasible in establishing the estimation standard for skeletal age determination using developmental metaphysis and anthropometry. The standard may be particularly helpful in forensic practice for estimation of accurate criminal responsible age in adolescents.

Comparative evaluation of hand wrist radiographs with cervical vertebrae for skeletal maturation in 10-12 years old children.

A comparative evaluation of hand wrist and cervical vertebrae was done to know the validity of cervical vertebrae as maturity indicators. A sample of 50 subjects (25 females and 25 males) in the age group of 10-12 years were selected on criteria of normal occlusion and the result showed that cervical vertebrae can be used with the same confidence as hand wrist radiographs to evaluate skeletal maturity, thus avoiding the need for an additional radiograph.