WHAT SYMPTOMS DOES A PERSON WITH PERIPHERAL NEUROPATHY EXPERIENCE?

Motor symptoms

The main function of motor nerves is to carry signals from the brain to various muscles, organs and glands in the body.

These nerves are responsible for controlling the voluntary movements of muscles to perform actions such as talking, picking things up or walking, as well as activating the unconscious movement of our abdominal, thoracic and pelvic organs.

Motor nerve damage is commonly associated with the following symptoms^[55-58]:

• • Weakness: muscle weakness is the most common symptom of motor nerve damage, especially affecting the limbs.
• • Lack of coordination: difficulty in maintaining coordination and balance, which can lead to difficulty in walking or falls.
• • Cramps: sudden, brief, involuntary and painful contraction of a muscle or group of muscles, usually in the hands and feet.
• • Fasciculations: rapid, involuntary and arrhythmic contractions or spasms of the muscle, which are visible through the skin.
• • Muscle atrophy: severe reduction in muscle mass that can lead to motor difficulties, such as getting up from a chair, climbing stairs or raising the arms.
• • Stiffness: lack of muscle flexibility.
• • Decreased or absent reflexes: tendon reflexes may be compromised.

Sensory symptoms

The main function of sensory nerves is to transmit information from the body’s tissues and from the senses to the central nervous system. All this information allows us to take decisions or act in a certain way.

Damage to the sensory nerves can cause a wide range of symptoms; primarily^[55-58]:

• • Numbness: stiffness or lack of flexibility or movement in a limb of the body, accompanied by unpleasant sensations in that part of the body (tingling, clumsiness).
• • Tingling: gradual burning sensation, pins and needles, electrical sensation or numbness. It often starts in the feet or hands and may extend upwards to involve the legs and arms.
• • Loss of sensation: decreased ability to feel pain or temperature changes, usually in the hands and feet. Those affected may no longer notice that they have been injured or that they have other acute conditions. It is a particularly serious problem for people with diabetes, contributing to the high rate of lower limb amputations in this population. There is often a feeling of tightness in the extremities, as if wearing tight stockings or gloves.
• • Extreme pain and tenderness: increased sensitivity to touch, pain or temperature, causing sharp, burning, throbbing, pulsating, stabbing pain, usually in the feet and/or hands. Those affected experience an exaggerated sensitisation of pain receptors in the skin, causing stimuli that do not normally hurt to cause severe pain (allodynia), such as the touch of bed sheets.

Autonomic symptoms

Autonomic nerves control the activities of organs that are automatically regulated, such as breathing, digestion, heart and gland functions.

Damage to the autonomic nerves is variable, as they are responsible for almost every organ in the body. However, the most common symptoms are^[55-58]:

• • Dizziness and fainting: low blood pressure causes light-headedness or fainting due to an inability to control the muscles that regulate blood pressure by expanding or contracting blood vessels. Those affected may experience dizziness when standing up after lying or sitting.
• • Genitourinary disorders: loss of bladder control.
• • Sweating abnormalities: inability to sweat normally, which may cause heat intolerance, excessive sweating or inability to sweat.
• • Sexual difficulties: such as erectile dysfunction in men.
• • Changes in digestive function: abnormal functioning of the nerves that control intestinal muscle contractions may cause diarrhoea, constipation or incontinence. Eating or swallowing difficulties sometimes occur if the autonomic nerves that control these functions are compromised.