A sitting disability is a condition in which a person may not be able to sit, usually due to pain, but can also happen to persons sitting in wheelchairs. It is also known as "reduced ability to sit", "sitting problems" or "inability to sit."
Sitting disability has generally been an unrecognized disability. It is also not a well known concept, though the symptoms themselves are common for people with severe back pain. The disabilities usually mentioned in research and legal documents are reduced mobility and visual or auditory impairments.
Pain while sitting is a well known symptom when having ischial tuberosity pain, Myofascial Pain Syndrome, coccyx pain (coccydynia), failed back surgery, Arachnoiditis, and back pain in general. An inability to sit is one of the signs of chronic low back pain. Low back pain is a condition that affects a large part of the general United States population at some point in life. 65 to 80% of Americans have an episode of  low back pain at some time in their lives. Although most cases resolve quickly, 40% recur and 5% result in a residual disability after 1 year.
In the U.S., acute low back pain (also called lumbago) is the fifth most common reason for all physician visits. About nine out of ten adults experience back pain at some point in their life, and five out of ten working adults have back pain every year.
It is possible to get Social Security benefits for a sitting disability. Several medical conditions that can cause difficulty sitting are back injuries, sciatica, Arachnoiditis, and piriformis syndrome. 
Sitting problems are usually an invisible disability. This combined with the fact that reduced ability to sit is not mentioned in research or anti-discrimination laws, makes it even harder for people to live with this kind of impairment.
Equality and accessibility
A person with a sitting disability caused by excessive pain, is unable to sit or stand for long periods of time, and will need to lie down. The availability of benches or other devices where one may lie down may be a critical factor that determines whether a means of transportation or a public building is usable or not for many people with this form of disability. Public buildings and transportation such as flying are often inaccessible to people with severe sitting problems. People with both sitting- and mobility problems often have to use a wheelbench, which is usually too large to fit into an elevator.
A sitting disability is a medical condition that makes a person unable to sit, not unable to move. It is not the inability to access the building that prevents a person from being in a building, it is the lack of places to lie down or comfortable reclining chairs. Accommodations for people who have a sitting disability are being enforced as Western nations integrate Universal design into their societies. The Norwegian organization for chronic pain Friends International Support Group (FISG), has described how the sitting disabled are discriminated in a document to the Anti-Discrimination Ombud in Norway. The Ombud shall enforce The Anti Discrimination and Accessibility Act (DTL). In 2013 the Ombud ruled that a person with sitting disability was discriminated when denied transport for disabled people.
For some medical conditions like Pudendal neuralgia, avoiding activities like sitting, which worsen the condition, is regarded as crucial. A severe sitting disability requires major life adjustments.
People who suffer from this are often totally disabled in that there are few jobs in which a person is able to lie down, and not required to stand or sit for extended periods of time. Sufferers in the United States are unseen because of a lack of suitable mass transit, and the lack of public places to lie down in a socially acceptable manner. Sufferers often remain at home even though they may be totally ambulatory. (Please note that although a wheel cart is mentioned, despite the need, there is no company that mass produces them.) People with sitting problems often find it embarrassing to lie down in public.
A noncommercial video about sitting disability has been running on Norwegian national TV on holidays the whole 2013. It will continue to run in 2014 to inform people about this special disability.
The American college radio DJ Laurie Cohen has neuropathy in her pelvis after she was rear ended in a car accident. The severe pelvic pain prevents her from being able to sit. 
- Norwegian article at The National Centre for Documentation on Disability
- Caring Medical - Ischial Tuberosity Pain
- USU - Back Pain
- Dartmouth-Hitchcock Medical Centre - Chronic Low Back Pain
- Patel AT, Ogle AA (March 2000). "Diagnosis and management of acute low back pain". Am Fam Physician 61 (6): 1779–86, 1789–90. PMID 10750882.
- Social Security benefits for a sitting disability
- LDO ruling about the right to transport for sitting disabled
- Benson JT, Griffis K (May 2005). "Pudendal neuralgia, a severe pain syndrome". Am. J. Obstet. Gynecol. 192 (5): 1663–8. doi:10.1016/j.ajog.2005.01.051. PMID 15902174.
- Physicians Perspective Treatment
- What people with sitting disability think
- Video about sitting disability
- Sitting disability because of severe pelvic pain