Recurrent pain is pain that arises periodically and can result in absences from school, outside activities, etc. This type of pain may be the most common.

Descriptions are:

- periodic instead of persistent

- consisting of tension and migraine headaches

- abdominal pains

- chest pain and limb pains

Chronic pain in children is unresolved pain that affects activities of daily living and may result in a significant amount of missed school days. It is characterized as mild to severe and is present for long periods of time. Chronic pain can develop from disease or injury with acute pain. Some have described chronic pain as the pain experienced when the child reports a headache, abdominal pain, back pain, generalized pain or combinations of these. Children that experience chronic pain can have psychological effects. In addition, families may also suffer emotionally when the child experiences pain. Caring for a child in pain does have social consequences related to the disability and limitations that accompany the pain. In regards to outside factors, finding solutions for children in pain may generate additional costs from healthcare and lost wages because of the necessary time off from work.

In 1994, responding to the need for a more useful system for describing chronic pain, the International Association for the Study of Pain (IASP) classified pain according to specific characteristics:

1. region of the body involved (e.g. abdomen, lower limbs),

2. system whose dysfunction may be causing the pain (e.g., nervous, gastrointestinal),

3. duration and pattern of occurrence,

4. intensity and time since onset, and

5. cause

However, this system has been criticized by Clifford J. Woolf and others as inadequate for guiding research and treatment.

Woolf suggests three classes of pain:

1. nociceptive pain,

2. inflammatory pain which is associated with tissue damage and the infiltration of immune cells, and

3. pathological pain which is a disease state caused by damage to the nervous system or by its abnormal function (e.g. fibromyalgia, peripheral neuropathy, tension type headache, etc.).

The DSM-IV-TR specifies three coded subdiagnoses: pain disorder associated with psychological factors, pain disorder associated with both psychological factors and a general medical condition and pain disorder associated with a general medical condition (although the latter subtype is not considered a mental disorder and is coded separately within the DSM-IV-TR). Conditions such as dyspareunia, somatization disorder, conversion disorder, or mood disorders can eliminate pain disorder as a diagnosis. Diagnosis depends on the ability of physicians to explain the symptoms and on psychological influences.

Pain disorder is chronic pain experienced by a patient in one or more areas, and is thought to be caused by psychological stress. The pain is often so severe that it disables the patient from proper functioning. Duration may be as short as a few days or as long as many years. The disorder may begin at any age, and occurs more frequently in girls than boys. This disorder often occurs after an accident or during an illness that has caused pain, which then takes on a 'life' of its own.

Phantom pain is pain felt in a part of the body that has been amputated, or from which the brain no longer receives signals. It is a type of neuropathic pain.

The prevalence of phantom pain in upper limb amputees is nearly 82%, and in lower limb amputees is 54%. One study found that eight days after amputation, 72% of patients had phantom limb pain, and six months later, 67% reported it. Some amputees experience continuous pain that varies in intensity or quality; others experience several bouts of pain per day, or it may reoccur less often. It is often described as shooting, crushing, burning or cramping. If the pain is continuous for a long period, parts of the intact body may become sensitized, so that touching them evokes pain in the phantom limb. Phantom limb pain may accompany urination or defecation.

Local anesthetic injections into the nerves or sensitive areas of the stump may relieve pain for days, weeks, or sometimes permanently, despite the drug wearing off in a matter of hours; and small injections of saline into the soft tissue between vertebrae produces local pain that radiates into the phantom limb for ten minutes or so and may be followed by hours, weeks or even longer of partial or total relief from phantom pain. Vigorous vibration or electrical stimulation of the stump, or current from electrodes surgically implanted onto the spinal cord, all produce relief in some patients.

Mirror box therapy produces the illusion of movement and touch in a phantom limb which in turn may cause a reduction in pain.

Paraplegia, the loss of sensation and voluntary motor control after serious spinal cord damage, may be accompanied by girdle pain at the level of the spinal cord damage, visceral pain evoked by a filling bladder or bowel, or, in five to ten per cent of paraplegics, phantom body pain in areas of complete sensory loss. This phantom body pain is initially described as burning or tingling, but may evolve into severe crushing or pinching pain, or the sensation of fire running down the legs or of a knife twisting in the flesh. Onset may be immediate or may not occur until years after the disabling injury. Surgical treatment rarely provides lasting relief.

The most prominent symptoms of erythromelalgia are episodes of erythema, swelling, a painful deep-aching of the soft tissue (usually either radiating or shooting) and tenderness, along with a painful burning sensation primarily in the extremities. These symptoms are often symmetric and affect the lower extremities more frequently than the upper extremities. Symptoms may also affect the ears and face. For secondary erythromelalgia, attacks typically precede and are precipitated by the underlying primary condition. For primary erythromelalgia, attacks can last from an hour to months at a time and occur infrequently to frequently with multiple times daily. Common triggers for these episodes are exertion, heating of the affected extremities, and alcohol or caffeine consumption, and any pressure applied to the limbs. In some patients sugar and even melon consumption have also been known to provoke attacks. Many of those with primary erythromelalgia avoid wearing shoes or socks as the heat this generates is known to produce erythromelalgia attacks. Raynaud's phenomenon often coexists in patients with Erythromelalgia. Symptoms may present gradually and incrementally, sometimes taking years to become intense enough for patients to seek medical care. In other cases symptoms emerge full blown with onset.

PRS symptoms have common characteristics with many other psychiatric disorders. However, none of the present DSM diagnoses can account for the full scope of symptoms seen in PRS, and refusal to eat, weight loss, social withdrawal and school refusal can be considered as the main distinctive features. Any system may be involved, however some more commonly engaged than others.

Gastrointestinal:

- recurring pain

- nausea

- loss of appetite

Neurological:

- headache

- seizure

- motor dysfunction

- sensory dysfunction

- fatigue

- altered consciousness

Musculoskeletal:

- joint pains

- muscle weakness

The main symptom of enteric neuropathy is severe and constant pain. Other symptoms include nausea, vomiting, diarrhoea, constipation, bloating and abdominal abnormalities. In addition malabsorption and poor nutrition are common, as the digestive system begins to fail. Symptom management is very important and the main priority is usually to get on top of the pain. However, as most people may have been waiting for years for a diagnosis they are often already addicted to painkillers (such as tramadol and oramorph) and these have adverse effects on the primary condition.

Audioanalgesia (also known as audio-analgesia) is the relief of pain using white noise or music without using pharmacological agents while doing painful medical procedures such as dental treatments. It was first introduced by Gardner and Licklider in 1959.

There are many studies of this technique in dental, obstetric, and palliative care contexts. The most recent review reports mixed results for effectiveness. This questionable pain management strategy might prove useful in distraction and sensory confusion, but only when combined with actual pain relief medications. There is no research to suggest these dubious results will ever be effective other than as a means of self-distraction. This measure is similar to breathing exercises during cramps before administration of epidurals.

It has also been suggested that music may stimulate the production of endorphins and catecholamines.

The condition is characterised by aversive reactions to feeding and oral stimulation including Co-Symptoms. It can occur one week after tube insertion.

- Food refusal/Head turning

- Loss of appetite/disinterest

- Oversensitivity for touching, smelling, tasting food

- Nausea

- Gagging

- Retching

- Vomiting

- Anxiety attacks

The most commonly used diagnostic criteria and definition of CFS for research and clinical purposes were published by the United States Centers for Disease Control and Prevention (CDC). The CDC currently recommends the following criteria for diagnosis:

1. Significantly lowered ability to participate in activities that were routine before the onset of the condition, and persisting more than six months

2. Physical or mental activity causes worsening symptoms that would not have been problematic before the onset of the condition, (post-exertional malaise (PEM))

3. Sleep problems

Additionally, one of the following symptoms must be present:

- Difficulty with thinking and memory

- Worsening of problems with standing or sitting

Other common symptoms may include:

- Muscle pain, joint pain, and headache pain

- Tender lymph nodes in the neck or armpits

- Sore throat

- Irritable bowel syndrome

- Night sweats

- Sensitivities to foods, odors, chemicals, or noise

The CDC proposes that persons with symptoms resembling those of CFS consult a physician to rule out several treatable illnesses: Lyme disease, "sleep disorders, major depressive disorder, alcohol/substance abuse, diabetes, hypothyroidism, mononucleosis (mono), lupus, multiple sclerosis (MS), chronic hepatitis and various malignancies." Medications can also cause side effects that mimic symptoms of CFS. Central sensitization, or increased sensitivity to sensory stimuli such as pain have been observed in CFS. Sensitivity to pain increases post-exertionally, which is opposite to the normal pattern.

Studies have mixed results as to whether a gradual onset or sudden onset is more frequent.

Erythromelalgia can be found in several billing codes systems and other systems. Erythromelalgia is generally classified as a disease of the circulatory system, falling under the class of "other peripheral vascular disease", as the following two billing code systems will show:

ICD-9-CM

According to the ICD-9-CM database (International Classification of Diseases, Ninth Revision, Clinical Modification), Erythromelalgia is listed under Diseases of the Circulatory System and is identified by number 443.82.

ICD-9-CM Diagnosis Codes > Diseases of the circulatory system (390-459) > Diseases of arteries, arterioles, and capillaries (440-449) > Other peripheral vascular disease (443) > Other specified peripheral vascular disease (443.8) > Erythromelalgia (443.82).

ICD-10-CM

According to the ICD-10-CM database (International Classification of Diseases, Tenth Revision, Clinical Modification), Erythromelalgia is listed under Diseases of the circulatory system and is identified by I73.81.

ICD-10-CM Diagnosis Codes > Diseases of the circulatory system (I00-I99) > Diseases of arteries, arterioles and capillaries (I70-I79) > Other peripheral vascular diseases (173-9) > Erythromelalgia (I73.81)

Mesh

According to the MESH database (Medical Subject Headings), Erythromelalgia is classified under the unique ID number of D004916.

OMIM

According to the OMIM database (NCBI - Online Mendelian Inheritance in Man), Primary Erythromelalgia is listed under the number: 133020.

Pervasive refusal syndrome (PRS), now referred to as pervasive arousal withdrawal syndrome (PAWS), is a rare but serious child psychiatric disorder that was first described by Bryan Lask and colleagues in 1991. As of 2011, it is not included in the standard psychiatric classification systems. PRS is the name allotted to a disorder in which children have abandoned their involvement in all phases of their life. It's characterized by refusal to eat, drink, talk, walk or self-care, and a firm resistance to treatment. PRS is very rare and its cause is unclear, but its severity makes it life-threatening. The disorder usually begins with a 'virus', or the child having a 'pain', that results in the need for consulting a doctor or going to the hospital, even though no substantial cause can be found. PRS starts slowly, but the child then worsens quickly becoming reluctant or not capable to do anything for themselves. They originally refuse to accept others caring for them, or helping them eat, and are very depressed and distraught. It is not guaranteed that recovery will take place, and it is a lengthy and complex process, involving specialist medical care. Nevertheless, once the patient is healthy, relapse is very infrequent.

A family with a psychiatric history or environmental stress factors can also play a role. Hospitalization is almost always necessary and the recovery period is lengthy; typically 12.8 months. During the recovery period symptoms disappear in the opposite order they appear. About 67% of the cases show complete recovery.

PRS may be linked to learned helplessness, and so it can be important for the patient to be able to manage the rate of their recovery. Music therapy may help in this regard as it provides empowerment by giving the patient choice and control, while allowing for improvisation can result in a sense of affirmation and validation; all important for a successful recovery.

Functional constipation, known as chronic idiopathic constipation (CIC), is constipation that does not have a physical (anatomical) or physiological (hormonal or other body chemistry) cause. It may have a neurological, psychological or psychosomatic cause. A person with functional constipation may be healthy, yet has difficulty defecating.

Enteric neuropathy is a degenerative neuromuscular condition of the digestive system. In simple terms the gut stops functioning, due to degradation of the nerves and muscles. The condition affects all parts of the digestive tract. There is no known cure or treatment for enteric neuropathy at this time; it is only possible to work on symptom management.

The name enteric neuropathy only seems to be used for diagnosis within the UK. The most common name worldwide for this condition is Intestinal pseudoobstruction.

Tube dependency refers to the process in which an individual becomes dependent on a feeding tube for nutrition. While the term technically refers to any individual who requires enteral feeding for nutrition, some practitioners specifically use this term for patients, primarily children, who are medically capable of eating by mouth but have been unable to wean from a feeding tube due to non-medical causes, which may be behavioral, sensory, or motoric in nature.

Chronic idiopathic constipation is similar to constipation-predominant irritable bowel syndrome (IBS-C); however, people with CIC do not have other symptoms of IBS, such as abdominal pain. Diagnosing CIC can be difficult as other syndromes must be ruled out as there is no physiological cause for CIC. Doctors will typically look for other symptoms, such as blood in stool, weight loss, low blood count, or other symptoms.

To be considered functional constipation, symptoms must be present at least a fourth of the time.

Possible causes are:

- Anismus

- Descending perineum syndrome

- Other inability or unwillingness to control the external anal sphincter, which normally is under voluntary control

- A poor diet

- An unwillingness to defecate

- Nervous reactions, including prolonged and/or chronic stress and anxiety, that close the internal anal sphincter, a muscle that is not under voluntary control

- Deeper psychosomatic disorders which sometimes affect digestion and the absorption of water in the colon

There is also possibility of presentation with other comorbid symptoms such as headache, especially in children.

Arthralgia (from Greek "arthro-", joint + "-algos", pain) literally means "joint pain"; it is a symptom of injury, infection, illnesses (in particular arthritis) or an allergic reaction to medication.

According to MeSH, the term "arthralgia" should only be used when the condition is non-inflammatory, and the term "arthritis" should be used when the condition is inflammatory.

Loin Pain Hematuria Syndrome ", aka "LPHS, is the combination of debilitating unilateral or bilateral flank pain and microscopic or macroscopic amounts of blood in the urine that is otherwise unexplained.

Loin pain-hematuria syndrome (LPHS) is a poorly defined disorder characterized by recurrent or persistent loin (flank) pain and hematuria that appears to represent glomerular bleeding. Most patients present with both manifestations, but some present with loin pain or hematuria alone. Pain episodes are rarely associated with low-grade fever and dysuria, but urinary tract infection is not present. The major causes of flank pain and hematuria, such as nephrolithiasis and blood clot, are typically not present. Renal arteriography may suggest focally impaired cortical perfusion, while renal biopsy may show interstitial fibrosis and arterial sclerosis.

The pain is typically severe, and narcotic therapy is often prescribed as a way to manage chronic pain. Sleep can be difficult because the supine position increases pressure on the flank. The onset of pain is often associated with nausea and vomiting, making pain management by oral opiates complicated.

"Adhesive capsulitis" (also known as "frozen shoulder") is a painful and disabling disorder of unclear cause in which the shoulder capsule, the connective tissue surrounding the glenohumeral joint of the shoulder, becomes inflamed and stiff, greatly restricting motion and causing chronic pain. Pain is usually constant, worse at night, and with cold weather. Certain movements or bumps can provoke episodes of tremendous pain and cramping. The condition is thought to be caused by injury or trauma to the area and may have an autoimmune component.

Risk factors for frozen shoulder include tonic seizures, diabetes mellitus, stroke, accidents, lung disease, connective tissue diseases, thyroid disease, and heart disease. Treatment may be painful and taxing and consists of physical therapy, occupational therapy, medication, massage therapy, hydrodilatation or surgery. A physician may also perform manipulation under anesthesia, which breaks up the adhesions and scar tissue in the joint to help restore some range of motion. Alternative treatments exist such as the Trigenics OAT Procedure, ART, and the OTZ method. But these can vary in efficacy depending on the type and severity of the frozen shoulder. Pain and inflammation can be controlled with analgesics and NSAIDs.

People who suffer from adhesive capsulitis usually experience severe pain and sleep deprivation for prolonged periods due to pain that gets worse when lying still and restricted movement/positions. The condition can lead to depression, problems in the neck and back, and severe weight loss due to long-term lack of deep sleep. People who suffer from adhesive capsulitis may have extreme difficulty concentrating, working, or performing daily life activities for extended periods of time. The condition tends to be self-limiting and usually resolves over time without surgery. Most people regain about 90% of shoulder motion over time.

Colic is defined as episodes of crying for more than three hours a day, for more than three days a week for a three-week duration in an otherwise healthy child between the ages of two weeks and four months. By contrast, infants normally cry an average of just over two hours a day, with the duration peaking at six weeks. With colic, periods of crying most commonly happen in the evening and for no obvious reason. Associated symptoms may include legs pulled up to the stomach, a flushed face, clenched hands, and a wrinkled brow. The cry is often high pitched (piercing).

The causes of "arthralgia" are varied and range, from a joints perspective, from degenerative and destructive processes such as osteoarthritis and sports injuries to inflammation of tissues surrounding the joints, such as bursitis. These might be triggered by other things, such as infections or vaccinations.

An infant with colic may affect family stability and be a cause of short-term anxiety or depression in the father and mother. It may also contribute to exhaustion and stress in the parents.

Persistent infant crying has been associated with severe marital discord, postpartum depression, early termination of breastfeeding, frequent visits to doctors, and a quadrupling of excessive laboratory tests and prescription of medication for acid reflux. Babies with colic may be exposed to abuse, especially shaken baby syndrome.