AMPHIARTHROSIS, in Anatomy, a neutral or dubious kind of Articulation, distinguished from the Diarthrosis, in that it has no apparent Motion; and from the Synarthrosis, in its not being absolutely devoid of Motion. See ARTICULATION, DIARTHROSIS, etc. Such is the Articulation of the Ribs, with the Vertebrae; and that of the Carpus with the Tarsus, &c. See VERTEBRAE, CARPUS, etc. The Word, according to Dioscorides, is derived from amphi, both, and arthrosis, Articulation; the Amphiarthrosis being compounded of both the other sorts. Whence some also call it, Cyakebhais onate Prattal.
AMPHIBLESTROIDES, in Anatomy, a Tunic, or Coat of the Eye, more usually called Retina. See RETINA. The Word is Greek, amphiblestroides, from amphiblestron, Rete, Net; compounded of amphi, circum, around, blestron, I cast; and eidos, Form; by reason of its Net-like Texture: whence the Latins also call it Retiformis.
AMPUTATION, in Chirurgery, the Operation of cutting off a Limb, or other Part of the Body, with an Instrument of Steel. See CHIRURGERY, OPERATION, etc. In Cases of Mortification, recourse is frequently had to Amputation. See MORTIFICATION, GANGRENE, SPHACELUS, etc. The Method of performing it, in the Instance of a Leg, is as follows—The proper Part for the Operation being four or five Inches below the Knee; the Skin and Flesh are first to be drawn very tight upwards, and secured from returning by a Ligature two or three Fingers broad: above this Ligature another loose one is passed, for the Gripe, which being twisted by means of a Stick, may be straitened to any degree at pleasure. Then, the Patient being conveniently situated, and the Operator placed to the inside of the Limb; which is to be held by one Assistant above, and another below the Part designed for the Operation; and the Gripe sufficiently twisted, to prevent too large a Hemorrhage, the Flesh is, with a Stroke or two, to be separated from the Bone with the Dismembering-Knife. Then the Periosteum being also divided from the Bone with the Back of the Knife, saw the Bone asunder with as few Strokes as possible—When two parallel Bones are concerned, the Flesh that grows between them must likewise be separated, before the use of the Saw.
ANASTOMOSIS, or Anastomoses, in Anatomy, is sometimes used to express such an Opening of the Mouths of the Vessels, as lets out their Contents. See VESSEL, etc. The Word is formed from the Greek ἀναστόμωσις (anastomōsis), from ἀνά (ana, through) and στόμα (stoma, mouth).
Anastomoses are more frequently used to denote the opening of two Vessels into one another; or the Union and Juncture of the Mouths of two Vessels, whereby they come to communicate with one another. There are various Anastomoses of this kind, e.g., of an Artery with an Artery, a Vein with a Vein, or a Vein with an Artery. See ARTERY, and VEIN. The Circulation of the Blood in the Fetus is effected by means of the Anastomoses, or Inosculation of the Vena Cava with the Pulmonary Vein; and of the Pulmonary Artery with the Aorta. See FETUS.
Anastomoses are more frequently used to denote the opening of two Vessels into one another; or the Union and Juncture of the Mouths of two Vessels, whereby they come to communicate with one another. There are various Anastomoses of this kind, e.g., of an Artery with an Artery, a Vein with a Vein, or a Vein with an Artery. See ARTERY, and VEIN. The Circulation of the Blood in the Fetus is effected by means of the Anastomoses, or Inosculation of the Vena Cava with the Pulmonary Vein; and of the Pulmonary Artery with the Aorta. See FETUS.
ANATOMY, the Art of dissecting, or artificially taking to pieces, the solid Parts of Animal Bodies; in order to an exact Discovery of their Structure and Economy. See ANIMAL, BODY, DISSECTION, and ECONOMY.
Anatomy makes a great Branch of that Division of Medicine called Physiology. See MEDICINE, and PHYSIOLOGY.
Anatomy makes a great Branch of that Division of Medicine called Physiology. See MEDICINE, and PHYSIOLOGY.
ANCYLODES, is used by some Writers in Anatomy, for the Process or shooting forth of the Shoulder-bone, in form of a Beak. See OMOPLATE.
ANISCALPTOR, in Anatomy, a Muscle, otherwise called Latissimus Dorsi.
ANNUENTES Musculi, in Anatomy, a Pair of transverse Muscles, at the Root of the Vertebrae of the Back; called also by Mr. Cowper, Resi interni minorres, because they lie under the Resi majores. See RESI. They are called Annuentes, because they help to nod the Head directly forward. See HEAD, MUSCLES, etc.