Hypoesthesia (or hypesthesia) refer to a reduced sense of touch or sensation, or a partial loss of sensitivity to sensory stimuli. In everyday speech this is sometimes referred to as "numbness".

Hypoesthesia is one of the negative sensory symptoms associated with cutaneous sensory disorder (CSD). In this condition, patients have abnormal disagreeable skin sensations that can be increased (stinging, itching or burning) or decreased (numbness or hypoesthesia). There are no other apparent medical diagnoses to explain these symptoms.

Cutaneous hyperesthesia has been associated with diagnosis of appendicitis in children but this symptom was not supported by the evidence.

Hypoesthesia originating in (and extending centrally from) the feet, fingers, navel, and/or lips is one of the common symptoms of beriberi, which is a set of symptoms caused by thiamine deficiency.

Hypoesthesia is also one of the more common manifestations of decompression sickness (DCS), along with joint pain, rash and generalized fatigue.

In most cases, the cause of acoustic neuromas is unknown. The only statistically significant risk factor for developing an acoustic neuroma is having a rare genetic condition called neurofibromatosis type 2 (NF2). There are no confirmed environmental risk factors for acoustic neuroma. There are conflicting studies on the association between acoustic neuromas and cellular phone use and repeated exposure to loud noise. In 2011, an arm of the World Health Organization released a statement listing cell phone use as a low grade cancer risk. The Acoustic Neuroma Association recommends that cell phone users use a hands-free device.

Meningiomas are significantly more common in women than in men; they are most common in middle-aged women. Two predisposing factors associated with meningiomas for which at least some evidence exists are exposure to ionizing radiation (cancer treatment of brain tumors) and hormone replacement therapy.

The overall complication rate following surgery is around 20%; cerebrospinal fluid leak is the most common.

Below are a list of commonly reported symptoms associated with sacral Tarlov cysts:

Back pain, perineal pain, secondary Sciatica, secondary piriformis muscle dysfunction with tertiary sciatica, Cauda equina syndrome, neurogenic claudication (pain caused by walking), neurogenic bladder, dysuria, urinary incontinence, coccygodynia, sacral radiculopathy, radicular pain, headaches, retrograde ejaculation, paresthesia, hypesthesia, secondary pelvic floor dysfunction, vaginismus, motor disorders in lower limbs and the genital, perineal, or lumbosacral areas, sacral or buttocks pain, vaginal or penile paraesthesia, Persistent Genital Arousal Disorder (PGAD) characterized by unwanted, unrelenting genital sensory awareness, itch or pain that can persist for days, months, even years), sensory changes over buttocks, perineal area, and lower extremity; difficulty walking; severe lower abdominal pain, bowel dysfunction, intestinal motility disorders like constipation or bowel incontinence.

When Tarlov cysts are ruptured or drained they cause leakage of cerebrospinal fluid (CSF). Ruptures of Tarlov cysts have been reported associated with communicating aneurysms and from fracture in the proximity of the cysts. An undetected rupture can cause intracranial hypotension, including orthostatic neurological symptoms along with headache, nausea, and vomiting that improve when supine. The ruptured cysts can be patched either with a biosynthetic dural patch or using a blood patch to stem the flow of CSF.

Because hearing loss in those with NF-2 almost always occurs after acquisition of verbal language skills, patients do not always integrate well into the Deaf culture and are more likely to resort to auditory assistive technology.

The most sophisticated of these devices is the cochlear implant, which can sometimes restore a high level of auditory function even when natural hearing is totally lost. However, the amount of destruction to the cochlear nerve caused by the typical NF2 schwannoma often precludes the use of such an implant. In these cases, an auditory brainstem implant (ABI) can restore a primitive level of hearing, which, when supplemented by lip reading, can restore a functional understanding of spoken language.

NF II is a microdeletion syndrome involving mutations in the NF2 gene located at 22q12.2 of chromosome 22. It is an inheritable disorder with an autosomal dominant mode of transmission. Incidence of the condition is about 1 in 60,000. There is a broad clinical spectrum known, but all patients checked have been found to have some mutation of the same gene on chromosome 22. Through statistics, it is suspected that one-half of cases are inherited, and one-half are the result of new, "de novo" mutations.