Anatomy and Embalming / A Treatise on the Science and Art of Embalming, the Latest and Most Successful Methods of Treatment and the General Anatomy Relating to this Subject

by Albert John Nunnamaker; Charles Otto Dhonau

Linear Guide.—By a linear guide is meant that an imaginary line is drawn from a point to a point the same direction the artery runs so that by mentally imagining this line one can be safe to cut on the line and be sure that the desired artery will be reached.

The linear guide for the carotid is represented by a line drawn from the sterno-clavicular junction to a point between the angle of the jaw and the lobe of the ear. (Mastoid process).

As the body lies on the cooling-board place one finger on the sterno-clavicular junction and the other at a point between the angle of the jaw and the lobe of the ear, and by cutting on this imaginary line, the artery will be reached, providing the artery is normal and if the embalmer is thoroughly acquainted with the anatomy about the artery, as is summed up in the anatomical guide.

Anatomical Guide.—By the anatomical guide is meant the relation which the artery bears to the surrounding tissues.

The anatomical guide for the carotid artery is that the artery lies between the sterno-mastoid muscle to the outside, and the muscles surrounding the trachea (wind pipe) and the esophagus, to the inside. In the middle third or sometimes between the middle and upper third the omohyoid muscle crosses over the artery.

Perpendicular Incision.—The artery is divided for the sake of description into thirds. By making an incision on the linear guide in any one of the thirds the tissues that must be passed through are the following:—skin, platysma muscle, superficial fascia, deep fascia, common sheath, and the individual sheath.

The platysma muscle is a broad tissue paper like muscle, placed immediately beneath the skin and a part of the superficial fascia, in the cervicle or neck region. It arises by thin fibrous bands from the fascia covering the pectoral and deltoid muscles on the thoracic wall, and passes upward over the clavicle and inserts the lower jaw. This muscle is so delicate and the fibers so finely divided that it is hardly perceptible. When the skin is cut, the platysma muscle will as a rule be cut too, and because of its thinness it will rarely be seen or does it form any hindrance to the raising of the artery. It is only mentioned here because it forms part of one of the questions so often asked by the State Board in their examination: “What tissues would you pass through in raising the carotid artery?”

Having cut through the skin and platysma muscle, the superficial fascia is next seen. In this part of the body it consists of but a single layer and very thin.

The deep fascia lies next and constitutes a complete investment of the neck. When this is torn or cut through the sternomastoid muscle comes into view.

The sternomastoid, is a large, thick muscle, which passes obliquely across the side of the neck, being inclosed between two layers of deep fascia. It has its origin at the sternum and clavicle and attaches to the mastoid process of the temporal bone. By making the perpendicular incision in the lower third, in as much as the muscle slightly covers the artery, it can either be cut or pushed to the outside of the incision. It is best to push the muscle to the outside with the thumb, and with the handle of the scalpel, work down deep through the areolar tissue. The operator will now arrive at the common sheath, or that part of the deep fascia surrounding the artery, vein and nerve. The common sheath will be very tough and a slit must first be cut, then it can be torn the length of the incision.