An increase in height of the medial longitudinal arch of the foot that does not flatten on weight bearing (i.e., a distinctly hollow form of the sole of the foot when it is bearing weight).

An abnormal hand position characterized by hyperextension of the fourth and fifth fingers at the metacarpophalangeal joints and flexion of the interphalangeal joints of the same fingers such that they are curled towards the palm.

Absence of neurologic reflexes such as the knee-jerk reaction.

Reduced ability to perceive painful stimuli.

Repeated episodes of segmental demyelination and remyelination lead to the accumulation of supernumerary Schwann cells around axons, which is referred to as onion bulb formation. This finding affects peripheral nerves.

A decrease in the ability to perceive vibration in the distal portions of the limbs.

A loss of myelinated nerve fibers in the peripheral nervous system (in general, this finding can be observed on nerve biopsy).

A type of decreased nerve conduction velocity that affects the motor neuron.

A pattern of simultaneous degeneration and regeneration of axons (see comment).

A reduced sense of touch (tactile sensation) on the skin of the distal limbs. This is usually tested with a wisp of cotton or a fine camel's hair brush, by asking patients to say 'now' each time they feel the stimulus.

A reduction in the amplitude of sensory nerve action potential in distal nerve segments. This feature is measured by nerve conduction studies.

Progressive deterioration of peripheral axons.

A flexion contracture is a bent (flexed) joint that cannot be straightened actively or passively. It is thus a chronic loss of joint motion due to structural changes in muscle, tendons, ligaments, or skin that prevents normal movement of joints.

Reduced strength of the musculature of the distal extremities.

Muscular atrophy affecting muscles in the distal portions of the extremities.

A lack of strength of the proximal muscles of the legs.

A lack of strength of the proximal muscles of the arms.

A progressive disorder of vertebral joint degeneration that occurs in the setting of any condition characterized by decreased afferent innervation, involving loss of deep pain and proprioceptive sensation in the vertebral column. Patients most commonly present with symptoms of lower back pain, sitting imbalance, progressive spinal deformity (usually kyphosis), and an audible clicking sound on changing postures.

Hoarseness refers to a change in the pitch or quality of the voice, with the voice sounding weak, very breathy, scratchy, or husky.

Decreased strength of the vocal folds.