Diabetes mellitus type I and II can be associated with macro- and microangiopathies. Thusly peripheral nerve function may be affected leading to paresthesias in the feet, and to other symptoms. The frequency of polyneuropathies correlates with the quality of blood sugar control. Meaning – the better blood glucose is controlled (normoglycemic) the less frequently a polyneuropathy gets manifest. Diabetic polyneuropathy affects all parts oft he peripheral nervous system.
Most frequently hypesthesias and paresthesias are realised in feet and hands (glove, stocking). The skin in the feet gets dry and vulnerable to mechanic stress. Patients are prone to onychomykosis (Fig. 1). In this case mechanical lesions should be avoided (Fig. 2) in order to prevent the development of ulcera (Fig. 3).
Some patients realise tingling and burning pain in their feet. Additionally autonomic functions are impaired such as the orthostatic regulation of blood pressure, gastric and urogenital function. Diabetic polyneuropathy can also lead to the lesion of single nerves such as cranial nerves (Fig. 4), abdominal nerves (Fig. 5) . This nerve lesion is painful and can be mixed up with intraabdominal disorders or nerves in the leg (Fig. 6).
The Burns Garland syndrome is mainly a mononeuropathy of the femoral nerve, which affects the quadriceps and iliopsoas muscles, also hip adductors, glutaei and knee flexors may be affected. Additionally to the femoralis other impaired nerves are obturatorius, sciatic nerve, glutaei, lumbar spinal nerves. Patients are usually diabetics older than 50 yrs. of age. The syndrome manifests itself in periods of bad blood sugar control. The progression can last for weeks and months. Usually the syndrome is combined with a distal sensory diabetic neuropathy. The paravertebral EMG shows signs of denervation, albumin is elevated in CSF. The best treatment is normoglycemic blood sugar control using insulin.
There is only symptomatic treatment available for diabetic polyneuropathy. Therefore, early diagnosis (by clinical investigation, nerve conduction studies and autonomic testing) and prevention of nerve lesion by normoglycemic control are of great importance.