Manual of practical anatomy : the upper limb / by J. Cossar-Ewart.

  • Cossar-Ewart, James, 1851-1933.
Date:
1879
Catalogue details

Licence: Public Domain Mark

Credit: Manual of practical anatomy : the upper limb / by J. Cossar-Ewart. Source: Wellcome Collection.

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

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    F. Tlie Pectoralis major and minor and the Subclavius muscles are now to be considered. 1. Pectoralis major (PI. IV.). OHgin.—(I) The sternal portion from the front of the sternum, the cartilages of all the true ribs except the seventh, and the aponeu- rosis of the external oblique abdominal muscle. (2) The clavicular portion from the inner part of the anterior border of the clavicle (PI. I. and III.). Insertion into the outer edge of the bicipital groove of the humerus (PI. VIII.), the clavicular fibres passing obliquely downwards, those from the ribs obliquely upwards; a double tendon is thus formed, the deeper and higher part of which belongs to the lowest or costal portion of the muscle. Action.—Rotates the hanging arm inwards and carries it forwards, so that the hand lies over the opposite thigh. Depresses and add acts the raised arm; or when the arm is raised and fixed, as in climbing, it raises the trunk to the same side; both acting, the trunk is raised vertically. Its lower edge forms the anterior fold of the axilla; its upper is in contact with the deltoid below but slightly removed from it near the clavicle, where the cephalic vein disappears to join the axillary. Nerves.—External (outer cord) and internal (inner cord) anterior i thoracic (PI. VI.). / Artei'y.—Acromial thoracic (axillary). ^ Indicate the direction of the fibres, and fill in the cutaneous nerves in PI. IV. Dissection.—Divide the clavicular portion of the muscle at its origin, and look for the nerves and vessels passing to it; and note the upper border of the pectoralis minor and the strong membrane (costo-coracoid) passing from it to be attached to the coracoid process, the lower border of the clavicle, and the first rib. Tliis membrane encloses the subclavius muscle, blends with the sheatli of the axillary vessels, and extends to the origin of the coraco- brachialis. It is penetrated by the acromio-thoracic vessels, cephalic vein, and external thoracic nerve. Divide the rest of the muscle four inches from its origin, and reflect the one part inwards, the other outwards; and note the dou])le
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