Pain Explained

Pain is the means by which the Peripheral Nervous System (PNS) warns the Central Nervous System (CNS) of injury or potential injury to the body. The CNS comprises of the brain and spinal cord and the PNS is composed of the nerves that stem from and lead into the CNS. The PNS includes all nerves throughout the body except the brain and spinal cord.

A pain signal is transmitted to the CNS by special PNS nerve cells called Nociceptors which are distributed throughout the body and respond to different stimuli depending on their location. Neurotransmitters are chemicals found within the nervous system that facilitate nerve cell communication. When a nociceptor is stimulated, neurotransmitters are released within the cell. The nociceptor transmits its signal to nerve cells within the spinal cord, which conveys the pain message to the thalamus, a specific region in the brain.

The body uses natural pain killers, called Endorphins, that are meant to reduce or stop further pain messages from the same source. However, these natural pain killers will not adequately dampen a continuing pain message. Also, depending on how the brain has processed the pain information, Prostaglandins hormone may be released. This hormone enhances the pain message and plays a role in immune system responses to injury, such as inflammation.

Following some disorders or physical injury, pain does not resolve. Even after healing the brain continues to perceive pain. In this situation, the pain may be considered to be Chronic Pain. Healthcare professionals consider chronic pain as pain that endures beyond a normal healing time. The pain associated with cancer, persistent and degenerative conditions, and neuropathy or nerve damage, is included in the chronic category. Also, constant pain that lacks an identifiable physical cause, such as the majority of cases of low back pain, may be considered chronic. The underlying biochemistry of Chronic Pain appears to be different from regular nociceptive pain.

Managing Pain

Pain, whether Acute or Chronic, forces pain patients to seek medical care, but physicians often focus on correcting the problem--with pain relief only a secondary consideration. Various intricacies and prejudices contribute to the under-treatment of pain, including the problem of accurately assessing the pain being suffered, the patient's fear of addiction to pain-killers and the government's (of most countries) zealous aversion to narcotic prescriptions.

Pain Management may require an interdisciplinary approach which includes treating the underlying cause of pain, pharmacological and nonpharmacological therapies, and surgical procedures. Treating the cause of pain is the primary attempt at managing it. Injuries are repaired, diseases are diagnosed, and certain episodes of pain can be anticipated and prevented. However, there are no guarantees of immediate relief from pain and even the healing process can be impeded by pain. Therefore, pharmacological and other therapies have developed over time to address these aspects of disease and injury.

A Podiatrist is a Pain Management Specialist. There are several approaches a Podiatrist will take to assessing pain. Generally these include a thorough patient history and physical exam, as well as discussing with the patient to identify these factors:

• The location of pain

• The quality of the pain - sharp, dull, aching, throbbing or burning.

• The frequency and duration of pain episodes

• Moderating and exacerbating factors in pain episodes

• The intensity of the pain on a 10-point visual analog scale - because of its inherent subjectivity, this part is usually is a stumbling block.

The Podiatrist also has to keep in mind that Chronic, unremitting pain can lead to Allodynia (pain from a non-painful stimulus), and "pain memory." Gender, Personality, Age and Ethnicity all factor into the patient's perception of pain and its evaluation. The Podiatrist will need to observe the patient for non-verbal signs of pain, such as facial grimacing, withdrawal, guarding, rubbing, limping, shifting of position, aggression, depression, moaning, and crying. Further he will need to watch for changes in behaviour from the patient's usual patterns.

Management through Pain Medication

Research and experience shows that Somatic Pain responds well to Acetaminophen, NSAID's, Opioids, local anesthesia, cold packs and other physical therapy modalities while management of Neuropathic Pain may include the use of tramadol, gabapentin, lidocaine patch, opioids, tricyclic and other antidepressants, anti-convulsants and capsaicin.

NSAIDs and Acetaminophen are effective for most forms of acute pain (sharp but of short course), but severe pain may require stronger medication. Narcotics handle intense pain effectively, and are used for cancer pain and acute pain that does not respond to NSAIDs and Acetaminophen. Narcotics are are available only with a doctor's prescription and are classified as Opiates or Opioids. Opiates include Morphine and Codeine, which are derived from Opium. Opioids are synthetic drugs based on the structure of Opium and this class includes drugs such as Oxycodon, Methadone, and Meperidine. Narcotics are usually not recommended for long-term use because the body develops a tolerance to narcotics, reducing their effectiveness over time. In such situations, pain can be managed with Antidepressants and Anticonvulsants.

Although Anti-depressant drugs were developed to treat depression, they were also found effective in combating chronic headaches, cancer pain, and pain associated with nerve damage. Anti-depressants that have been shown to have analgesic (pain reducing) properties include Amitriptyline (Elavil) and Trazodone. Anticonvulsant drugs were developed to treat epilepsy but were found to relieve pain as well. Anticonvulsant drugs such as Phenytoin (Dilantin) and Carbamazepine (Tegretol) are prescribed to treat the pain associated with nerve damage.

Other prescription medications are used to treat specific types of pain or specific pain syndromes. For example, Corticosteroids are very effective against pain caused by inflammation and swelling, and Sumatriptan (Imitrex) was developed specifically to treat migraine headaches.

Alternatives to Pain Medication

Other approaches to pain management include TENS, or Transcutaneous Electrical Nerve Stimulation which is a device that sends pulses of electrical current through the skin to block pain signals. TENS is very similar to acupuncture in the treatment of pain; it stimulates the nerves to block pain, but TENS is more convenient and doesn't involve breaking the skin. TENS is not recommended for pregnant women or people with pacemakers, but is worth a try for chronic pain sufferers. There are generally no side effects, except for occasional skin irritation which disappears soon after use.


Manipulation : Chiropractors and osteopathic physicians have used manipulation of the body for years to relieve pain. Recently this technique has gained acceptance within other parts of the medical community and now even physical therapists, orthopedic surgeons, and nurses use these techniques to relieve musculoskeletal pain.


Relaxation techniques : Hypnosis, guided imagery, controlled breathing and stretching are relaxation techniques used to control pain. Often, chronic pain causes physical tension which in turn works to create more pain. Relaxation techniques may not completely conquer pain, but they can help reduce it. Another hypothesis extended by relaxation experts is that when muscles are tense and tight, there is a lot of electricity in them and it's painful; when you relax, those electrical impulses reduce in intensity thereby reducing pain.

Pain Psychology : Long-term pain is likely to make the patient cranky and depressed. Pain Counseling is designed to help people carry on despite having pain; psychological support services teach patients how to stop concentrating on the pain. Pain Counselors may suggest anything from self-hypnosis to distracting your mind with activities.


Acupuncture : This involves the inserting of small needles into the skin at key points. Acupressure uses these same key points, but involves applying pressure rather than inserting needles. Acupuncture may work by prompting the body to release endorphins, which are natural pain-relieving chemicals in the body.


Surgery : Some chronic pain conditions can be corrected by cutting the nerve fibers that carry pain signals. While surgery may be a good idea for some pain, it is a last resort because destroying nerves leads to loss of sensation, and will not correct the pain problem.