Localized hypertrophic neuropathy is a nerve condition in which nerve cells increase in number and form bundles that look like onion bulbs. This condition affects one nerve, usually in an arm or leg. The symptoms of this condition include muscle weakness, numbness, and decreased reflexes in the affected limb. Symptoms slowly get worse over time. The cause of this condition is unknown, but some researchers believe it might be a type of tumor, while others believe it might be an unusual reaction to injury.

Because this condition is rare, there are no established guidelines for the treatment of localized hypertrophic neuropathy. Treatment is determined based on each individual's symptoms and personal medical history. Treatment usually consists of having surgery to remove the abnormal part of the nerve. Some individuals do not have surgery and their symptoms are monitored over time.

One article in the scientific literature described the prognosis of localized hypertrophic neuropathy for four individuals before and after treatment. In three individuals, treatment stabilized their symptoms, which means the weakness and numbness did not continue to get worse but stayed the same (stabilized). The fourth individual experienced improvement in strength following treatment. Though this article only examined four individuals, the authors state that other studies have found similar results, with all individuals' symptoms stabilizing and a few improving following treatment.