Observation – Posture
005-pos

Anatomy and Physiology
Maintaining proper posture requires normal vestibular, optic, and proprioceptive inputs. Posture involves motor responses to sensory inputs. These inputs are from receptors in the limbs, body, viscera, vestibular apparatus, and central nervous system.

Assessment
Posture must be evaluated while the patient is at rest. The position of the head, neck, back, and legs are evaluated.

1. Head
– Tilt/Twist
xx– If accompanied by scratching, may be otitis externa or ear mites
xx– If continuous, likely vestibular lesion
– Opisthotonus (dorsoflexion of head and neck) – lesions in brain stem or rostral cerebellum
– Ventroflexion in cats – lesions in brain stem or neuromuscular lesion

2. Trunk
– Congenital/acquired lesions of vertebrae
– Abnormal muscle tone due to lesions in spinal cord or brain
– Kyphosis – dorsal curvature of the spine
– Lordosis – ventral curvature of the spine
– Scoliosis – lateral deviation of the spine

2. Limbs
– Wide based stance - often seen with ataxia, abnormal conscious proprioception, and generalized weakness
– Knuckling - proprioceptive deficit, LMN or UMN lesion
– Uneven distribution of weight - weakness or pain
– Increased tone in extensor muscles - UMN
– Decreased tone - LMN lesion
– Schiff-Sherrington - increased tone in forelimbs with flaccid paralysis in hind limbs
– Lesion between T2 and L4
– Tetany - increased tone in flexors and extensors
– Strychnine poisoning and tetanus
– Decerebellate rigidity - opisthotonus, extension of thoracic limbs, and flexion of the pelvic limbs
– Decerebrate rigidity - opisthotonus, extension of all limbs, and severely altered mentation