To get the most out of this article, we strongly encourage you to first read the article/post on ‘What is diabetic neuropathy?’ to understand the various nerve types in the body, normal function of the different nerves in the body, how they can be affected by diabetes, and the various medical terms used to explain neuropathy.
Is there more than one type of diabetic neuropathy?
Diabetes can damage almost any type of nerve in the body. Depending on the type of nerves affected by diabetes, symptoms of neuropathy can vary from person to person. The different types of nerves in the body are explained in the article ‘What is diabetic neuropathy?’ Some people have several different symptoms of neuropathy due to damage to different types of nerve. Others may have only one type of neuropathy. The most common form of diabetic neuropathy is peripheral neuropathy or polyneuropathy.
Types of diabetic neuropathy and SYMPTOMS of each type of neuropathy
Some people will have only one type of neuropathy if only one type of nerves is affected. Others may have several different groups of symptoms of neuropathy due to damage to more than one type of nerves. The most common form of diabetic neuropathy is peripheral neuropathy or polyneuropathy.
Diabetic peripheral neuropathy or polyneuropathy: When diabetes affects the nerves in the feet, hands, legs or arms, which carry sensations of touch, temperature, pain, balance, etc (sensory nerves) or the nerves which control muscle movements in the legs or arms (motor nerves), this type of neuropathy is called diabetic polyneuropathy (‘poly’ is the term used to indicate ‘multiple’, thereby meaning that polyneuropathy is a condition affecting multiple nerves) or diabetic peripheral neuropathy (the term ‘peripheral’ is used to indicate that nerves at the ‘periphery’ of the body are affected, for example the feet or hands, sometimes spreading to the legs or arms).
As explained in the article ‘What is diabetic neuropathy?’, nerves in the feet, hands, legs and arms may be ‘sensory nerves’ or ‘motor nerves’. Depending on which of these two types of nerves or both, are affected, one may have either sensory neuropathy or motor neuropathy.
* Sensory peripheral neuropathy or sensory polyneuropathy causes loss or altered sensation of touch, temperature or position sense. This results in numbness, tingling, clumsiness or balance problems. There can also be altered sensation of pain causing either loss of the ability to feel painful sensations, or constant feeling of pain in the affected area. Some people will develop a sign in which the affected part (foot, hand, arm or leg) is very sensitive to touch. In medical terms, this is called ‘hyperaesthesia’. When there is actual pain to even light touch, this is an even worse sign called ‘allodynia’. People who have developed allodynia find it painful to wear socks, shoes or even have a bed sheet touch the affected foot or hand. Medical specialists use these terms to describe the signs of neuropathy- these and other signs used by doctors and other medical providers will be discussed in depth in the article ‘Diagnosis of diabetic neuropathy’. The most commonly affected part of the body is the feet. The neuropathy can spread to affect the legs as well. It can also affect the hands and feet.
* Motor peripheral neuropathy or motor polyneuropathy is the term given to the type of neuropathy that affects the ‘motor nerves’ and causes weakness of the feet, legs, hands or arms.
* Mixed (sensory and motor) peripheral neuropathy or polyneuropathy is the term used when a person has both sensory and motor neuropathy.
Usually the early symptoms of diabetic polyneuropathy or peripheral neuropathy are numbness and tingling (sensory neuropathy). At this stage, all attempts should be made to prevent further progress of the neuropathy. Preventive as well as treatment methods have been discussed in other articles on this website. If the neuropathy progresses, then hyperaesthesia and allodynia may develop. Further progression results in weakness (motor neuropathy). Diabetic peripheral neuropathy does not alway follow this sequence. Some people may experience a more rapid progression to the motor neuropathy. In others, there is sudden development of weakness in muscles controlled by a single nerve or a group of nerves. This is called ‘focal neuropathy’, discussed below along with some other types of neuropathy.
Other types of diabetic neuropathy are less common than peripheral neuropathy or polyneuropathy, but need to be mentioned.
One form of neuropathy called focal neuropathy involves sudden or rapid development of weakness in muscles controlled by a single nerve or a group of nerves. This can affect any part of the body, and may or may not be associated with pain.
In the condition called autonomic neuropathy, nerves that help control body functions are affected. Indigestion, nausea, vomiting, diarrhea or constipation can occur when the nerves to the stomach and intestines/bowel are affected. Abnormally high or low blood pressure can cause dizziness or fainting when the nerves that help control the heart and blood circulation are affected. Similarly, some other bodily functions that can be affected by diabetic neuropathy and cause problems are urinary retention (nerves to bladder affected), erectile dysfunction in men and vaginal dryness in woman (nerves to genital organs affected).
Conclusion
Thank you for reading this article, and we hope that you now have a good understanding of the possible symptoms associated with the different types of diabetic neuropathy, especially peripheral neuropathy or polyneuropathy. We would recommend that you next read about the clinical ‘signs’ and tests that doctors and other medical specialists use to diagnose diabetic neuropathy, in the article ‘Diagnosing diabetic neuropathy’. Or you may browse the other topics on this website related to diabetes and foot pain.