Chronic functional abdominal pain (CFAP) or functional abdominal pain syndrome (FAPS) is the ongoing presence of abdominal pain for which there is no known medical explanation. It is quite similar to, but less common than, irritable bowel syndrome (IBS), and many of the same treatments for IBS can also be of benefit to those with CFAP. The fundamental difference between IBS and CFAP is that in CFAP, unlike in IBS, there is no change in bowel habits such as constipation or diarrhea. Bowel dysfunction is a necessary diagnostic criterion of IBS. CFAP is characterized by chronic pain, with no physical explanation or findings (no structural, infectious, or mechanical causes can be found). People with chronic abdominal pain may also have other symptoms, depending on the cause. Whether it’s a mild stomach ache, sharp pain, or stomach cramps, abdominal pain can have numerous causes. Some of the more common causes include:

• Indigestion
• Constipation
• Stomach virus
• Menstrual cramps
• Irritable bowel syndrome (IBS)
• Food poisoning
• Food allergies
• Gas
• Lactose intolerance
• Ulcers
• Pelvic inflammatory disease
• Hernia
• Gallstones
• Kidney stones
• Endometriosis
• Crohn’s disease
• Urinary tract infection
• Gastroesophageal reflux disease (GERD)
• Appendicitis

Chronic knee pain is long-term pain, swelling, or sensitivity in one or both knees. The cause of your knee pain can determine the exact signs and symptoms you may experience. Injuries to the structure of the knee can cause bleeding and swelling, and over time, if the injury is not treated properly, it can create a chronic problem. Chronic knee pain rarely goes away without treatment, and it isn’t always attributable to one incident. It’s most often the result of several causes or conditions:

• Osteoarthritis: pain, inflammation, and joint destruction caused by degeneration and deterioration of the joint.
• Tendinitis: pain in the front of the knee that is made worse when climbing, taking stairs, or walking up an incline.
• Bursitis: inflammation caused by the repeated overuse or injury of the knee.
• Chondromalacia Patella: damaged cartilage under the kneecap.
• Gout: arthritis caused by the buildup of uric acid.
• Baker’s Cyst: a buildup of synovial fluid (fluid that lubricates the joint) behind the knee.
• Rheumatoid Arthritis: a chronic autoimmune inflammatory disorder that causes painful swelling and can eventually cause joint deformity and bone erosion.
• Dislocation: dislocation of the knee cap most often the result of trauma.
• Meniscus Tear: a rupture in one or more of the cartilage in the knee.
• Torn Ligament: tear in one of the four ligaments in the knee. The anterior cruciate ligament (ACL) is the most commonly injured ligament.
• Bone tumors: the second most prevalent bone cancer is osteosarcoma and most commonly occurs in the knee.

A number of factors and conditions can contribute to shoulder pain. The most prevalent cause is rotator cuff tendinitis. This is a condition characterized by inflamed tendons. Another common cause of shoulder pain is an impingement syndrome where the rotator cuff gets caught between the acromium (part of the scapula that covers the ball) and humeral head (the ball portion of the humerus). Sometimes shoulder pain is the result of injury to another location in your body, usually the neck or bicep. This is known as referred pain. Referred pain generally doesn’t get worse when you move your shoulder. Other causes of shoulder pain include several forms of arthritis, torn cartilage, or a torn rotator cuff. Swelling of the bursa sacs (which protect the shoulder) or tendons can also cause pain. Some people develop bone spurs, which are bony projections that develop along the edges of bones. Pinching a nerve in the neck or shoulder, or breaking a shoulder or arm bone, are also causes of pain. A frozen shoulder is when tendons, ligaments, and muscles stiffen and become difficult or impossible to move. A dislocated shoulder is when the ball of the humerus pulls out of the shoulder socket. An injury due to overuse or repetitive use can cause injury.

Coccydynia is a medical term meaning pain in the coccyx or tailbone area, usually brought on by sitting too abruptly.
Coccydynia can be anything from discomfort to acute pain, varying between people and varying with time in any individual. The name describes a pattern of symptoms (pain brought on or aggravated by sitting).
Coccydynia can follow after falls, childbirth, repetitive strain or surgery. In some cases the cause is unknown. The pain can disappear by itself or with treatment, or it can continue for years and may get worse. In most cases, the pain is caused by an unstable coccyx, which causes chronic inflammation.

Complex regional pain syndrome is an uncommon form of chronic pain that usually affects an arm or a leg. Complex regional pain syndrome typically develops after an injury, surgery, stroke or heart attack, but the pain is out of proportion to the severity of the initial injury. CRPS is a stronger than the normal reaction of the body to an injury. The cause of CRPS is not known. The nerves in the affected limb are much more sensitive than other nerves and this causes pain and tenderness in the affected area. The brain is also involved. The way the brain communicates with your affected arm or leg changes. The pain usually starts after an injury but may occur without an injury. It usually affects an arm or a leg but can affect another part of the body. The injury may be severe, such as a broken bone or a damaged nerve, or may be a minor injury.

Facet joint syndrome is a pain at the joint between two vertebrae in your spine. Another term for facet joint syndrome is osteoarthritis. The facet joints are the joints in your spine that make your back flexible and enable you to bend and twist. Nerves exit your spinal cord through these joints on their way to other parts of your body. Healthy facet joints have cartilage, which allows your vertebrae to move smoothly against each other without grinding. Each joint is lubricated with synovial fluid for additional protection against wear and tear. When your facet joints become swollen and painful due to osteoarthritis, it is called facet joint syndrome. Patients with facet joint syndrome have difficulty twisting and bending their spine. If you have facet joint syndrome in your cervical spine (your neck), you may have to turn your entire body to look left or right. Facet joint syndrome in your lumbar spine (low back) may make it difficult for you to straighten your back or get up out of a chair. Pain, numbness, and muscle weakness associated with facet joint syndrome will affect different parts of your body depending on which of your nerves are being affected. If the nerves affected are in your cervical spine, you may have symptoms in your neck, shoulders, arms and hands. If the nerves are in your lumbar spine you may have symptoms in your buttocks, legs, and feet.

Failed Back Syndrome (FBS) or Failed Back Surgery Syndrome (FBSS) (FBS) or (FBSS) is a generalized term that is used to describe the condition of patients who have experienced unsuccessful results following spine surgery to treat neck or back pain. Specifically, the term applies when spine surgery has not alleviated the original problem or has created other, more significant problems, resulting in continuing or worsening pain. It is characterized as a chronic pain syndrome. Multiple factors can contribute to the onset or development of FBS. Contributing factors include but are not limited to residual or recurrent spinal disc herniation, persistent post-operative pressure on a spinal nerve, altered joint mobility, joint hypermobility with instability, scar tissue (fibrosis), depression, anxiety, sleeplessness and spinal muscular deconditioning. An individual may be predisposed to the development of FBS due to systemic disorders such as diabetes, autoimmune disease and peripheral blood vessels (vascular) disease. Common symptoms associated with FBS include diffuse, dull and aching pain involving the back and/or legs.

There are five lumbar discs in the lower portion of your spine. These discs help cushion the spine from loads placed on it by gravity and physical activity. The discs have an outer ring called the anulus. This is made of multiple layers of fibrous tissue, similar to an automotive tire. Within this ‘tire’ is a central space filled with softer material called the nucleus. A spinal disc herniation occurs when a partial or full tear in the anulus allows a portion of nucleus to either bulge out or rupture. This can place pressure on nerves, causing pain. A herniated disc is a common injury that occurs when the soft nucleus of an intervertebral disc pushes through the tough outer annulus. Often, disc herniations occur in the lower region of the back known as the lumbar spine. This rupture of a vertebral disc can be caused by the normal wear of aging or by traumatic injury. A herniated disc can push against a nerve root, sending pain down the sciatic nerve and resulting in a burning, tingling and/or numbing sensation from the lower back down to one or both feet. A bulging disc injury is a common spine injury sustained to your spine’s intervertebral disc. It can occur in your lumbar spine (lower back), thoracic spine (upper and mid-back) or your cervical spine (neck). Discs situated between the spinal vertebrae absorb shock and facilitate movement. Bulging discs, which typically surface in the lower back, occur when a weakened or deteriorated disc swells through a crevice in the spine, extending outside of its normal jurisdiction. This condition happens when a disc shifts out of its normal position, usually slowly and over a long period of time. As the disc moves, its inner, liquid-like nucleus begins to balloon toward the weakest point in its hard outer casing.

A herniated disc refers to a problem with one of the rubbery cushions (discs) between the individual bones (vertebrae) that stack up to make your spine. Sometimes called a slipped disc or a ruptured disc, a herniated disc occurs when some of the softer “jelly” pushes out through a tear in the tougher exterior. A herniated disc can irritate nearby nerves and result in pain, numbness or weakness in an arm or leg. On the other hand, many people experience no symptoms from a herniated disc. You can have a slipped disc in any part of your spine, from your neck to your lower back. The lower back is one of the more common areas for slipped discs. Your spinal column is an intricate network of nerves and blood vessels. A slipped disc can place extra pressure on the nerves and muscles around it.

Symptoms of a slipped disc include:

• pain and numbness, most commonly on one side of the body
• pain that extends to your arms or legs
• pain that worsens at night or with certain movements
• pain that worsens after standing or sitting
• pain when walking short distances
• unexplained muscle weakness
• tingling, aching, or burning sensations in the affected area

A slipped disc occurs when the outer ring becomes weak or torn and allows the inner portion to slip out. This can happen with age. Certain motions may also cause a slipped disc. A disc can slip out of place while you are twisting or turning to lift an object. Lifting a very large, heavy object can place great strain on the lower back, resulting in a slipped disc. If you have a very physically demanding job that requires a lot of lifting, you may be at increased risk for slipped discs.

Lower back pain can be caused by a variety of problems with any parts of the complex, interconnected network of spinal muscles, nerves, bones, discs or tendons in the lumbar spine.
There are many different conditions that cause or contribute to low and lower back pain. Many involve nerve compression (eg, pinched nerve) that may generate pain and other symptoms. Types of spinal disorders include trauma-related and degenerative; meaning age-related. Some of these spinal problems are listed below.

• Bulging or herniated disc. A disc may bulge outward. A herniated disc occurs when the soft interior matter escapes through a crack or ruptures through the disc’s protective outer layer. Both disc problems can cause nerve compression, inflammation, and pain.
• Spinal stenosis develops when the spinal canal or a nerve passageway abnormally narrows.
• Spinal arthritis, also called spinal osteoarthritis or spondylosis, is a common degenerative spine problem. It affects the spine’s facet joints and may contribute to the development of bone spurs.
• Spondylolisthesis occurs when a lumbar (low back) vertebral body slips forward over the vertebra below it.
• Vertebral fractures (burst or compression types) are often caused by some type of trauma (eg, fall).
• Osteomyelitis is a bacterial infection that can develop in one of the spine’s bones.

In most cases, neck pain is attributed to muscle strain or a soft tissue sprain (ligaments, tendons), but it can also be caused by a sudden force (whiplash). These types of neck pain often improve with time and non-surgical care such as medication and chiropractic manipulation. But if neck pain continues or worsens, there is often a specific condition that requires treatment, such as cervical degenerative disc disease, cervical herniated disc, cervical stenosis, or cervical arthritis. The causes of neck pain are as varied as the list is long. Consider a few examples:

• Injury and Accidents: Whiplash is a common injury sustained during an auto accident. This is typically termed a hyperextension and/or hyperflexion injury because the head is forced to move backward and/or forward rapidly beyond the neck’s normal range of motion. The unnatural and forceful movement affects the muscles and ligaments in the neck. Muscles react by tightening and contracting creating muscle fatigue resulting in pain and stiffness.
• Growing Older: Degenerative disorders such as osteoarthritis, spinal stenosis, and degenerative disc disease are known to affect the spine.
• Everyday Life: Poor posture, obesity, and weak abdominal muscles disrupt the spine’s balance often causing the neck to bend forward to compensate. Stress and emotional tension can cause muscles to tighten and contract resulting in pain and stiffness.
• Other Disease Processes: Although neck pain is commonly caused by strain, prolonged pain and/or neurologic deficit may be an indication of something more serious. These symptoms should not be ignored. Spinal infection, spinal cord compression, tumor, fracture, and other disorders can occur. If a head injury has been sustained, more than likely the neck has been affected too. It is wise to seek medical attention promptly.

Peripheral neuropathy is disorder of nerve(s) apart from the brain and spinal cord. Patients with peripheral neuropathy may have tingling, numbness, unusual sensations, weakness, or burning pain in the affected area. Oftentimes, the symptoms are symmetrical and involve both hands and feet. Because the symptoms are often present in the areas covered by gloves or stockings, peripheral neuropathy is often described as having a “glove and stocking” distribution of symptoms. Neuropathy can present with many differing symptoms, including numbness, pain of different types, weakness, or loss of balance, depending on the type of nerve involved. Because the autonomic nerves control bodily functions, such as heart rate, digestion, and emptying of the bowel and bladder, autonomic neuropathy manifests with symptoms affecting the loss of control of these functions. Symptoms may include problems with blood pressure, voiding, passage of stools (diarrhea, or constipation), heart rate, or sweating.

Phantom pain is pain that feels like it’s coming from a body part that’s no longer there. Doctors once believed this post-amputation phenomenon was a psychological problem, but experts now recognize that these real sensations originate in the spinal cord and brain. Phantom pain occurs most often in people who’ve had an arm or leg removed, the disorder may also occur after surgeries to remove other body parts. Although the limb is no longer there, the nerve endings at the site of the amputation continue to send pain signals to the brain that make the brain think the limb is still there. Sometimes, the brain memory of pain is retained and is interpreted as pain, regardless of signals from injured nerves. For some people, phantom pain gets better over time without treatment. For others, managing phantom pain can be challenging. You and your doctor can work together to treat phantom pain effectively with medication or other therapies.

Postherpetic Neuralgia (PHN) Postherpetic neuralgia is a nerve pain due to damage caused by the varicella zoster virus which causes shingles. Typically, the neuralgia is confined to a dermatomic area of the skin, and follows an outbreak of herpes zoster (commonly known as shingles) in that same dermatomic area. PHN is a nerve pain (neuralgia) that persists after a shingles rash has cleared. If your pain from shingles goes but then returns at a later date, this too is called PHN. Shingles is an infection of a nerve and causes a typical rash. It is caused by the chickenpox (varicella-zoster) virus. About 1 in 5 people have shingles at some time in their lives. Shingles can occur at any age but it is most common in people aged over 50. Most people with shingles have pain but the pain usually eases soon after the rash clears. PHN is pain that persists (or returns in some people).

Osteoarthritis. The most common form of arthritis of the back, osteoarthritis is a chronic condition characterized by the breakdown of the cartilage that cushions the ends of the bones where they meet to form joints. In the spine, this breakdown occurs in the cartilage of the facet joints, where the vertebrae join. As a result, movement of the bones can cause irritation, further damage and the formation of bony outgrowths called spurs. These spurs can press on nerves, causing pain. New bone formation can also lead to narrowing of the spinal canal, known as spinal stenosis. Osteoarthritis of the spine may cause stiffness or pain in the neck or back. It may also cause weakness or numbness in the legs or arms if it is severe enough to affect spinal nerves or the spinal cord itself. Usually, the back discomfort is relieved when the person is lying down. Some people experience little interference with the activities of their lives. Others become more severely disabled. In addition to the physical effects, a person with osteoarthritis might also experience social and emotional problems. For instance, a person with osteoarthritis that hinders daily activities and job performance might feel depressed or helpless.

Spinal stenosis describes narrowing inside your spinal canal and mainly occurs from a combination of aging and degenerative changes in your spine. Wear and tear on the parts of your spine can cause discs to bulge, spine ligaments to thicken, and joints near your spinal canal to become enlarged. These can take up space inside your spinal canal and put pressure on your spinal nerves. Changes like these mostly affect people over 60 years of age. However, spinal stenosis also occurs in younger people who have abnormally small spinal canals from birth. Spinal stenosis usually causes back pain and leg pain that comes and goes with activities, such as walking. The leading reason for spinal stenosis is arthritis, a condition caused by the breakdown of cartilage — the cushiony material between your bones — and the growth of bone tissue. Osteoarthritis can lead to disc changes, a thickening of the ligaments of the spine, and bone spurs. This can put pressure on your spinal cord and spinal nerves.

Other causes include:

• Herniated discs. If the cushions are cracked, material can seep out and press on your spinal cord or nerves.
• Injuries. An accident may fracture or inflame part of your spine.
• Tumors. If cancerous growths touch the spinal cord, you may get stenosis.
• Paget’s disease. With this condition, your bones grow abnormally large and brittle. The result is a narrowing of the spinal canal and nerve problems.

Spondylolisthesis is a condition in which one bone in your back (vertebra) slides forward over the bone below it. It most often occurs in the lower spine. In some cases, this may lead to your spinal cord or nerve roots being squeezed. This can cause back pain and numbness or weakness in one or both legs. The bones in your spine come together at several small joints that keep the bones lined up while still allowing them to move. Spondylolisthesis is caused by a problem with one or more of these small joints that allows one bone to move out of line. Sometimes when a vertebra slips out of place, you may have no symptoms at all or no symptoms until years later. You may experience pain in your low back or buttock. The muscles in your leg may feel tight or weak and you may even limp.

Symptoms of spondylolisthesis may include:

• Back or buttock pain.
• Pain that runs from the lower back down one or both legs.
• Numbness or weakness in one or both legs.
• Difficulty walking.
• Leg, back, or buttock pain that gets worse when you bend over or twist.
• Loss of bladder or bowel control, in rare cases.

A vertebral compression fracture occurs when the block-like part of an individual bone of the spine (vertebrae) become compressed due to trauma. Usually the trauma necessary to break the bones of the spine is quite substantial. The vertebrae most commonly broken are those in the lower back, but they may break in any portion of the spine. Vertebral fractures of the thoracic and lumbar spine are usually associated with major trauma and can cause spinal cord damage that results in neural deficits. The main clinical symptoms of vertebral fractures typically include one or a combination of the following symptoms:

• Sudden onset of back pain
• Standing or walking will usually make the pain worse
• Lying on one’s back makes the pain less intense
• Limited spinal mobility
• Height loss
• Deformity and disability

Spinal fractures may also be caused by bone insufficiency. For example, people with osteoporosis, tumors, or other underlying conditions that weaken the bone can fracture a vertebra even during low-impact activities–such as reaching or twisting. These fractures may develop unnoticed over a period of time, with no symptoms or discomfort until a bone breaks.