An unpleasant sensation associated with actual or potential tissue damage, and mediated by specific nerve fibers to the brain where its conscious appreciation may be modified by various factors.
The word "pain" comes from the Latin: poena meaning punishment, a fine, a penalty.
The two most common forms of pain are headache and back pain.
Term used to denote a painful uterine contraction occurring in childbirth.
NERVE PATHWAY OF PAIN
The term "pain" is a subjective experience that typically accompanies nociception, but can also arise without any stimulus, and thus includes the emotional response.
Nociception, on the other hand, is a neurophysiological term and denotes specific activity in nerve pathways.
It is the transmission mechanism for physiological pain, and does not describe psychological pain.
These pathways transmit the nominally "painful" signals, though they are not always perceived as painful. Although pain can be associated with tissue damage or inflammation, this is often not the case.
Despite its causing suffering, pain is a critical component of the body's defense system.
It is part of a rapid warning relay instructing the central nervous system to initiate motor neurons in order to minimize detected physical harm.
Lack of the ability to experience pain, as in the rare condition Congenital insensitivity to pain or Congenital Analgesia, can cause various health problems.
Pain can be classified as acute or chronic .
Acute pain is defined as short-term but extreme pain that comes on quickly but last only for a brief period of time.
Acute pain is the body's warning of present damage to tissue or disease.
It is often fast and sharp followed by aching pain.
Acute pain is centralized in one area before becoming somewhat spread out.
This type of pain responds well to medications.
TYPES OF PAIN
Chronic pain was originally defined as pain that has lasted 6 months or longer.
It is now defined as pain that persists longer than the normal course of time associated with a particular type of injury.
This constant or intermittent pain has often outlived its purpose, as it does not help the body to prevent injury.
It is often more difficult to treat than acute pain.
Expert care is generally necessary to treat any pain that has become chronic, and coordinated treatment from an interdisciplinary health care team, including medical physicians, physical therapists, and psychologists or psychiatrists, often beneficial.
An anterior cingulectomy, neurosurgery that disconnects the anterior cingulate gyrus, can be used in extreme cases to treat chronic pain.
Post-surgery the patient will still feel the sensation of pain, but not the accompanying emotion.
There have been some theories that not treating acute pain properly can lead to chronic pain.
Pain associated with malignancy can be caused by the cancer itself or by treatment.
Non-malignant pain includes a variety of causes: arthritis, neuralgia, back pain from injury or disorders, migraines and other types of headaches, abdominal pain from chronic pancreatitis, bowel disorders, etc; pelvic pain from various conditions; and also diffuse conditions such as fibromyalgia, reflex sympathetic dystrophy, lupus and other systemic autoimmune/connective tissue conditions, multiple sclerosis and some other neuromuscular conditions.
Chronic pain can occur anywhere in the body; this list includes only a few examples of conditions that can cause chronic pain.
TYPES – MALIGNANT & NON-MALIGNANT
The experience of physiological pain can be grouped according to the source and related nociceptors (pain detecting neurons).
Cutaneous pain is caused by injury to the skin or superficial tissues.
Cutaneous nociceptors terminate just below the skin, and due to the high concentration of nerve endings, produce a well-defined, localized pain of short duration.
Examples of injuries that produce cutaneous pain include paper cuts, minor cuts,minor (first degree) burns and lacerations.
Somatic pain originates from ligaments, tendons, bones, blood vessels, and even nerves themselves.
It is detected with somatic nociceptors.
The scarcity of pain receptors in these areas produces a dull, poorly-localised pain of longer duration than cutaneous pain;
examples include sprains and broken bones.
Visceral pain originates from body's viscera, or organs.
Visceral nociceptors are located within body organs and internal cavities.
Visceral pain is extremely difficult to localize, and several injuries to visceral tissue exhibit "referred" pain, where the sensation is localized to an area completely unrelated to the site of injury.
The theory that visceral and somatic pain receptors converge and form synapses on the same spinal cord pain-transmitting neurons is called "Ruch's Hypothesis".
Phantom limb pain is the sensation of pain from a limb that has been lost or from which a person no longer receives physical signals.
It is an experience almost universally reported by amputees and quadriplegics.
PHANTOM LIMB PAIN
Neuropathic pain, or "neuralgia", can occur as a result of injury or disease to the nerve tissue itself.
This can disrupt the ability of the sensory nerves to transmit correct information to the thalamus, and hence the brain interprets painful stimuli even though there is no obvious or known physiologic cause for the pain.
Emotional pain Pain that is caused by extreme sadness resulting in physical manifiestation usually in the torso. Sometimes described as a feeling of ripping.
FEELING AT A DISTANCE
Head and neck
Jaw - Temporal arteritis (serious), trauma
Ear - otitis media (very common esp. in children), otitis externa, trauma
Left and right upper quadrant - peptic ulcer disease, gastroenteritis, hepatitis, pancreatitis, cholecystitis, MI (atypical), abdominal aortic aneurysm, gastric cancer (usually asymptomatic)
Left and right lower quadrant - appendicitis (serious), ectopic pregnancy (serious/women only), pelvic inflammatory disease (women only), diverticulitis (common in old), urolithiasis (kidney stone), pyelonephritis, cancer (colorectal cancer most common)
Back - MSK (muscle strain), cancer, spinal disc herniation, degenerative disc disease, also see joints section
Arm - MI (classically left, sometimes bilateral), MSK
Leg - deep vein thrombosis, peripheral vascular disease (claudication), MSK, spinal disc herniation, sciatica
Classically small joints - osteoarthritis (common in old), rheumatoid arthritis, systemic lupus erythematosis, gout, pseudogout
Classically large joints (hip, knee) - osteoarthritis (common in old), septic arthritis, hemarthrosis, trauma
Classically back - ankylosing spondylitis, inflammatory bowel disease
Other - psoriatic arthritis, Reiter's syndrome
Children have been proven to be markedly more sensitive to pain, but this fact is commonly dismissed as a fear reaction or a lack of coping abilities.
Research has been carried out on how children can cope with pain due to increased sensitivity and it has been established that strategies that remove pain can help prevent long-term increases in sensitivity as the nervous system is still developing.
CHILDREN AND PAIN
Chronic pain is essentially caused by the bombardment of the central nervous system (CNS) with nociceptive impulses, which causes changes in the neural response.
The pain subsequently provokes changes in the behavior of the patient, and the development of fear-avoidance strategies.
As a result, the patient may also become physically atrophied and deconditioned.
However, it is important to remember that chronic pain is multifactorial, with the underlying biological changes affecting physical and psychosocial factors.
CT Scan or CAT scan
Fine Needle Aspiration Biopsy (FNA)
Full Blood Count or Complete Blood Count
Full Physical Examination
MRI (Magnetic Resonance Imaging)
PET Scan (Positron Emission Tomography)
Ultrasound (Ultrasound Scanning or Sonography and Doppler)
X-Ray (General Radiology and Fluoroscopy)
Cognitive-Behavioural Therapy (CBT)
Corticosteroids for pain relief
Introduction to Neurostimulation
Nerve blocks (Regional anaesthesia)
Opioids for analgesia
Paediatric pain management
Spinal Cord Stimulation
Spinal Cord Stimulation Devices
Sympathectomy and Sympathetic Nerve Block
Trigger Point Injection of Local Anaesthetic
Pain management (also called pain medicine) is the discipline concerned with the relief of pain.
Pain has been described as, "An unpleasant sensory and emotional experience associated with either actual or potential tissue damage.
It is a very personal and individual experience - defined as whatever the patient says it is, and it exists wherever he or she says it does."
Acute pain, such as occurs with trauma, often has a reversible cause and may require only transient measures and correction of the underlying problem.
Chronic pain often results from conditions that are difficult to diagnose and treat, and that may take a long time to reverse.
Pain management generally benefits from a multidisciplinary approach that includes
Pharmacologic measures (analgesics such as narcotics or NSAIDs and pain modifiers such as tricyclic antidepressants or anticonvulsants)
Non-pharmacologic measures (such as interventional procedures, physical therapy and physical exercise, application of ice and/or heat),
Psychological measures (such as biofeedback and cognitive therapy).
Chronic pain is often more difficult to treat than acute pain.
Expert physician care is generally necessary to treat any pain that has become chronic and usually involves a multi-disciplinary team which may include a combination of physiotherapists, psychologists, counselors, and specialists, such as cancer or palliative care nurses for cancer or physicians who specialize in spine medicine for back pain.
CHRONIC PAIN MANAGEMENT
Depression is common for patients with chronic back pain, and it is important to treat both the pain and depression.
In managing chronic pain and in choosing which painkillers to use, beneficial analgesic effects must be balanced against any suffered drug side-effects if overall quality of life is to be improved.
For example, with opioids, patients may need to adjust the dosage to reach a compromise between actual pain-killing effect and an acceptable level of nausea or constipation.
Also called a narcotic or painkiller are used for prolonged periods drug tolerance, chemical dependency and (rarely) psychological addiction may occur.
Chemical dependency is somewhat common among opioid users; however, psychological addiction rarely occurs.
Apparent drug tolerance to the pain-relieving effects of opioids may occur.
This may be confused with progression of the underlying disease in cancer patients, back pain patients and other chronic pain sufferers, rather than an actual decrease in efficacy of the drug.
Drugs within this class act centrally on the brain to down regulate the perceived painful stimulus.
Drugs having this effect were fortuitously identified whilst being used to treat unrelated conditions.
The first such group were the tricyclic antidepressants (in particular amitriptyline) and the dose required is far lower than that used to treat depression.
Similarly some of the anticonvulsant drugs are used for this (in particular carbamazepine sodium valproate and gabapentin).
For most of these drugs, their use in chronic pain management is off-label.
The injection of a mixture of steroid and anaesthetic into the specific pressure points in the body where the pain is located in an attempt to disburse contracted tissue that could be causing the disturbance.