Terminology

A. Planes:         A flat surface, real or imaginary, passing through the animal, or part of it.

1.         MEDIAN: divides the body into equal left and right halves

2.         SAGITTAL: divides the body into unequal left and right portions, is parallel to the median plane

3.         TRANSVERSE: cuts perpendicular to median plane, dividing body into cranial and caudal parts, or cuts an organ or limb at a right angle to its long axis.

4.         DORSAL: cuts perpendicular to both median and transverse planes, dividing body into dorsal and ventral portions [= FRONTAL  or CORONAL plane]

5.         LONGITUDINAL: cuts parallel to the long axis of an organ or limb, may be in the median, sagittal or dorsal planes

B. Descriptive terms: Assume quadruped standing on all four limbs

1.         DORSAL: away from the ground (e.g. the vertebrae are dorsal to the intestines) [= POSTERIER]. On the limbs it applies to the upper or front surfaces of the limbs from the carpus [=wrist] or tarsus [=ankle] and distally (to the phalanges/toes).

2.         VENTRAL: towards the ground (e.g. the mammary glands are ventral to the intestines) [= ANTERIOR].

3.         CRANIAL: towards the head (e.g. the shoulder is cranial to the hindlimb) [= SUPERIOR]. Applies to the limbs to the level of the proximal carpus/tarsus when surface is then known as dorsal.

4.         CAUDAL: towards the tail (e.g. the diaphragm is caudal to the neck) [= INFERIOR, at least with regards to the body]. Applies to the limbs to the level of the proximal carpus/tarsus when surface is then known as palmer/plantar.

5.         ROSTRAL: a part on the head that is closer to the nose (= cranial for the rest of the body, e.g. the nares are rostral to the eyes).

6.         PALMAR: the surface directed caudally or towards the ground from the proximal carpus (hence foreleg only) and distally.

7.         PLANTAR: the surface directed caudally or towards the ground from the proximal tarsus (hence hindlimb only) and distally.

8.         MEDIAL: towards the median plane (e.g. the prepuce is medial to the stifle).

9.         LATERAL: farther from the median plane (e.g. the forelimbs are lateral to the heart).

10.       PROXIMAL: nearest the trunk or point of origin of a limb, vessel, nerve or organ (e.g. the shoulder is proximal to the elbow).

11.       DISTAL: farther from the trunk or point of origin of a limb, vessel, nerve or organ (e.g. the hock is distal to the stifle).

12.       SUPERFICIAL: nearer the surface (e.g. the eye is superficial to the brain).

 13.      DEEP: farther from the surface (e.g. the heart is deep to the ribs).

14.       PERIPHERAL: distant from its point of origin; near the surface of the body (e.g. peripheral nervous system, as apposed to the central nervous system – the brain and spinal cord).

15.       AXIS: is the centre line of the body or any of its parts. In ruminants (even-toed) and carnivores (five toes) the functional axis of the limb passes between digits III and IV. In horses (one toe) the axis passes through the only digit (III).

16.       AXIAL: Pertaining to the digits, the side of the digit closer to the longitudinal axis (facing inside).

17.       ABAXIAL: Pertaining to the digits, the side of the digit facing away from the longitudinal axis (facing outside).

18.       VISCERAL: associated with organs within the body cavities

19.       PARIETAL: associated with the body wall (e.g. parietal peritoneum lines the abdominal cavity). Also refers to terminology associated with the parietal bone of the skull.

20.       IPSILATERAL: same side of the body as another structure (e.g. left ear is ipsilateral to the left hindleg).

21.       CONTRALATERAL: opposite side of body as another structure (e.g. left foreleg is contralateral to the right hindleg).

22.       SUPRA-: prefix signifying above or over (e.g. supraspinatus muscle)

23.       INFRA-: prefix signifying below or beneath (e.g. infraspinatus muscle)

C. Basic movement terminology

                        1.         PROTRACTION: moving the whole limb forward (cranially).

                        2.         RETRACTION: moving the whole limb backwards (caudally).

3.         EXTENSION: movement of one bone in relation to another which results in the angle formed at that joint being increased (NB. over-extension may occur in some joints).

4.         FLEXION: movement of one bone in relation to another which results in the angle formed at that joint being decreased.

5.         PRONATION: as applied to the manus (hand), medial rotation of the forearm which results in the palmar surface facing downward (normal position of paw in carnivores).

6.         SUPINATION: as applied to the manus, lateral rotation of the forearm resulting in the palmar surface facing medially or upward (e.g. when cat licking paws).

7.         ABDUCTION: the movement of a part away from the median plane (e.g. dog urinating).

8.         ADDUCTION: the movement of a part towards the median plane.

D. Common abbreviations

                        cd.       caudal (or caud.)                                   a.         artery

                        cr.        cranial (or cran.)                                   v.          vein

                        ext.      external                                               m.        muscle

                        int.       internal                                                n.         nerve

                        lat.       lateral                                                  ln.        lymph node

                        med.    medial

                        CNS      central nervous system

                        ANS      autonomic nervous sytem