Holden's human osteology : comprising a description of the bones with delineations of the attachments of the muscles, the general and microscopic structure of bone and its development / edited by Charles Stewart and R.W. Reid.

  • Holden, Luther, 1815-1905.
Date:
1887
Catalogue details

Licence: Public Domain Mark

Credit: Holden's human osteology : comprising a description of the bones with delineations of the attachments of the muscles, the general and microscopic structure of bone and its development / edited by Charles Stewart and R.W. Reid. Source: Wellcome Collection.

    318/508 (page 232)
    lations of the second row of carpal bones with the metacarpals. Starting from the great toe, or thumb side, these bones articu- late with 2, 1, 3, and 2 metatarsal and metacarpal bones respectively. THE ASTEAGALUS. - (Plate XXXVI.) The XLey-Stone s its Six Aspects.—The astragalus {aa-rpd- yakos, talus, the knuckle bone, with which the ancients used to play atjdice) is the key-stone of the arch of the foot, and supports the whole weight of the body, which, in the erect position, faUs perpendicularly upon it from the tibia. It is so much concerned in the mechanism of the spring of the foot, that the Germans call it the ' spring bone.' To examine it thoroughly study its six su7faGes. Stjpbeior Sueface.—The superior surface, broad and risiag up slightly at its outer border m the transverse dii-ection, the best adapted for the erect posture, presents a pulley-like convexity in the antero-posterior direction, which articulates with the tibia, and admits of the flexion and extension of the ankle. The pulley-hke surface is at least one-fifth of an inch broader in front than behind. This prevents dislocation of the astragalus back- wards, which would otherwise be a more frequent occurrence, considering the du-ection of the force in walking, running, or leaping. The broad side of the pulley is the outer one. The inner edge of the pulley is nearly straight from behind forwards and inwards, while the outer one is more prominent and makes a sweep inwards on its way forwards. The articular surface of the pulley is continuous over the edges with the articular surfaces on the sides of the bone. In front of the trochlear surface is a rough narrow and depressed part of the bone, marked by nutrient foramina and affording attachment to the anterior ligament of the ankle joint. It is sometimes called the upper surface of the ' neck ' of the bone.