Apotemnophia / Body Integrity Disorder (BIID) is a is a rare, infrequently studied and highly secretive condition in which there is a mismatch between the mental body image and the physical body. Apotemnomphilia is characterized by an intense desire for amputation of a limb. Currently BIID is not included in the International Statistical Classification of Diseases 11 or the Diagnostic and Statistical Manual of Mental Disorders IV. It is often not known to surgeons, neurologists and psychiatrists. BIID individuals typically avoid healthcare and often act out their desires by pretending they are disabled or perform actual self-amputation.

A 2012 study concluded, based on interviews with 54 individuals, that the main rationale for their desire for body modification (amputation) was to feel complete or to feel satisfied inside. Based on the results of the survey, researchers concluded that psychotherapy was often supportive, but did not help diminishing BIID symptoms. Individuals reported that antidepressants were helpful in reducing depressive symptoms related to BIID, but that antipsychotics were not. Actual amputation of the limb was effective in all 7 cases who had surgical treatment.

Apotemnophilia has been studied for a number of years to determine whether this disorder is actually neurological or psychological. However, in-depth research related to apotemnophilia and its correlation to the mind and body are still not clear. Recent research has shown small breakthroughs such that apotemnophiles are three times more likely to want removal of a left limb than right, in accordance with damage to the right parietal lobe, and also in concordance with sufferers of somatoparaphrenia; in addition, skin conductance response is significantly different above and below the line of desired amputation, and the line of desired amputation remains stable over time, with the desire often beginning in early childhood. Among a convenience sample of 52 apotemnophiles recruited from internet groups, the great majority wanted a single leg removed, cut above the knee. There are parallels between apotemnophilia as a motivation for body integrity identity disorder and autogynephilia as a motivation for some cases of male-to-female gender dysphoria.

A 2014 review concluded that