Introduction to pain management
Pain management can be simple or complex, depending on the cause of the pain. An example of pain that is typically less complex would be nerve root irritation from a herniated disc with pain radiating down the leg. This condition can often be alleviated with an epidural steroid injection and physical therapy. Sometimes, however, the pain does not go away. This can require a wide variety of skills and techniques to treat the pain. These skills and techniques include:
- Interventional procedures
- Medication management
- Physical therapy or chiropractic therapy
- Psychological counseling and support
- Acupuncture and other alternative therapies; and
- Referral to other medical specialists
All of these skills and services are necessary because pain can involve many aspects of a person's daily life.
How is pain treatment guided?
The treatment of pain is guided by the history of the pain, its intensity, duration, aggravating and relieving conditions, and structures involved in causing the pain. In order for a structure to cause pain, it must have a nerve supply, be susceptible to injury, and stimulation of the structure should cause pain. The concept behind most interventional procedures for treating pain is that there is a specific structure in the body with nerves of sensation that is generating the pain. Pain management has a role in identifying the precise source of the problem and isolating the optimal treatment.
Fluoroscopy is an X-ray guided viewing method. Fluoroscopy is often used to assist the doctor in precisely locating the injection so that the medication reaches the appropriate spot and only the appropriate spot. Ultrasound is also used to identify structures and guide injections.
What are the basic types of pain?
There are many sources of pain. One way of dividing these sources of pain is to divide them into two groups, nociceptive pain and neuropathic pain. How pain is treated depends in large part upon what type of pain it is.
Examples of nociceptive pain are a cut or a broken bone. Tissue damage or injury initiates signals that are transferred through peripheral nerves to the brain via the spinal cord. Pain signals are modulated throughout the pathways. This is how we become aware that something is hurting.
Neuropathic pain is pain caused by damage or disease that affects the nervous system. Sometimes there is no obvious source of pain, and this pain can occur spontaneously. Classic examples of this pain are shingles and diabetic peripheral neuropathy. It is pain that can occur after nerves are cut or after a stroke.
Most back, leg, and arm pain is nociceptive pain. Nociceptive pain can be divided into two parts, radicular or somatic.
Radicular pain: Radicular pain is pain that stems from irritation of the nerve roots, for example, from a disc herniation. It goes down the leg or arm in the distribution of the nerve that exits from the nerve root at the spinal cord. Associated with radicular pain is radiculopathy, which is weakness, numbness, tingling or loss of reflexes in the distribution of the nerve.
Somatic pain: Somatic pain is pain limited to the back or thighs. The problem that doctors and patients face with back pain, is that after a patient goes to the doctor and has an appropriate history taken, a physical exam performed, and appropriate imaging studies (for example, X-rays, MRIs or CT scans), the doctor can only make an exact diagnosis a minority of the time. The cause of most back pain is not identified and is classifies as idiopathic. Three structures in the back which frequently cause back pain are the facet joints, the discs, and the sacroiliac joint. The facet joints are small joints in the back of the spine that provide stability and limit how far you can bend back or twist. The discs are the "shock absorbers" that are located between each of the bony building blocks (vertebrae) of the spine. The sacroiliac joint is a joint at the buttock area that serves in normal walking and helps to transfer weight from the upper body onto the legs.
Fluoroscopically (x-ray) guided injections can help to determine from where pain is coming. Once the pain has been accurately diagnosed, it can be optimally treated.
Neuropathic pain includes:
- Complex regional pain syndrome (CRPS), also called reflex sympathetic dystrophy;
- Sympathetically maintained pain;
- Interstitial cystitis; and
- Irritable bowel syndrome.
Treatment of neuropathic pain
The various neuropathic pains can be difficult to treat. However, with careful diagnosis and often a combination of methods of treatments, there is an excellent chance of improving the pain and return of function.
Medications are a mainstay of treatment of neuropathic pain. In general, they work by influencing how pain information is handled by the body. Most pain information is filtered out by the central nervous system, usually at the level of the spinal cord. For example, if you are sitting in a chair, your peripheral nerves send the response to the pressure between your body and the chair to your nervous system. However, because that information serves no usual purpose, it is filtered out in the spinal cord. Many medications to treat neuropathic pain operate on this filtering process. The types of medications used for neuropathic pain include antidepressants, which influence the amount of serotonin or norepinephrine, and antiseizure medications, which act on various neurotransmitters, such as GABA and glycine.
One of the most powerful tools in treating neuropathic pain is the spinal cord stimulator, which delivers tiny amounts of electrical energy directly onto the spine. Stimulation works by interrupting inappropriate pain information being sent up to the brain. It also creates a tingling in the pain extremity, which masks pain.
What are other causes of pain?
Other causes of pain include:
- facial pain,
- peripheral nerve pain,
- compression fractures,
- post-herpetic neuralgia,
- piriformis syndrome,
- plantar fasciitis,
- lateral epicondylitis, and
- cancer pain .
Headaches and facial pain, including atypical facial pain and trigeminal neuralgia.
Headaches are a major source of discomfort and lost productivity in the workplace. Many effective treatments exist for persisting headaches, including medication, biofeedback, injections and implants, depending upon the precise type of headache. Botox also provides a useful means of effectively and safely treating headaches.
Atypical facial pain can be debilitating. Often times it can be treated by injections into local nerve tissue (such as the sphenopalatine ganglion).
Trigeminal neuralgia, also called tic douloureux, is a condition that most commonly causes very intense intermittent shooting pain in the face.
Peripheral nerve pain
Peripheral nerve pain, or neuropathy, can be debilitating. It can respond well to simple treatments such a trigger point injections with anesthetic medicines and cryoablation (an office based procedure which involves freezing the nerves). Examples of peripheral nerve pain include intercostal neuralgia, ilioinguinal neuroma, hypogastric neuroma, lateral femoral cutaneous nerve entrapment, interdigital neuroma and related nerve entrapments.
Coccydynia is simply pain in the region on the tailbone, or coccyx. It can result from trauma or arise without apparent cause. The initial treatment is conservative, with oral pain relief medicines (analgesics). Oftentimes, the pain originates in the portion of the nervous system that we have no control of (involuntary or autonomic nervous system) and can respond to either a local anesthetic injection of the head of a nerve called Ganglion Impar, which is located below the coccyx or by medically destroying (ablating) the Ganglion Impar, usually using radiofrequency.
Compression fractures of the bony building blocks (vertebral bodies) are common in the elderly as a result of osteoporosis, or loss of calcium in the bone. With less calcium, the bone becomes weak and can break. Like any fracture, compression fractures hurt. Like any fracture, they are treated by stabilization, in this case, by injecting cement into the bone in a procedure known as a vertebroplasty or kyphoplasty. Vertebroplasty is an effective way to treat the pain of compression fractures. Kyphoplasty uses a balloon to restore height to the compressed vertebral body.
Post herpetic neuralgia (PHN) is a painful condition occurring after a bout of shingles. When we are young, we are almost all exposed to chickenpox, caused by the Herpes Zoster virus. Our immune system controls the virus, but it lives in a dormant state in the spinal cord. When we age, or become ill or stressed, the virus can reactivate and attack the infected nerve and adjacent skin. However, in this second attack, the body usually recognizes the Herpes Zoster virus and contains the pain to a localized area, along the course of one nerve. A patient may have the characteristic blisters, which normally heal. Sometimes, however, the Herpes Zoster virus damages the nerve, causing ongoing nerve pain that persists after the skin blisters from the shingles have healed.
The ideal way to treat the post herpetic neuralgia is to treat it before it sets in. Medications, such as acyclovir (Zovirax), steroids and injections such as sympathetic injections can help prevent the onset of PHN. After the pain is present, injections, local anesthetics, medications [duloxetine (Cymbalta), amitriptyline, (Elavil, Endep)] and pain medications or topical patches can be useful.
Myofasciitis and Torticollis
Myofasciitis (pain in the muscles, whether in the neck or back) often responds to conservative physical therapy treatments (for example, massage and exercise). If the pain persists, trigger point injections can be used. If the trigger point injections provide temporary relief, sometimes Botox injections can help. Botox, which is botulinum toxin, can relax the muscles for six or more months, with long-term relief of pain. It provides a safe, effective treatment for what can otherwise be a difficult, ongoing problem.
Torticollis is spasm of the muscles in the neck, forcing the sufferer to hold his or her neck tilted or rotated to the side. Botox is approved for treatment of this problem.
The piriformis muscle goes from the hip to sacrum (tailbone). It is important in that the sciatic nerve passes through it. Piriformis syndrome is a spasm of the piriformis muscle. When the muscle goes into spasm, it can squeeze the sciatic nerve, causing pain going down the leg. Piriformis syndrome will usually respond to physical therapy. When pain persists, local anesthetic and/or steroid injection can help. If the pain persists, injecting Botox or Myobloc, which are both botulinum toxins, into the muscle can provide effective, safe treatment.
Plantar fasciitis and lateral epicondylitis
Plantar fasciitis (heel pain) and lateral epicondylitis (tennis elbow) are two common pain problems. Treatment starts with conservative options, such as rest, non-steroidal anti-inflammatory medications, steroid injections, over-the counter pain medications, physical therapy and, for heel pain, shoe inserts.
If the pain lasts for more than six months, Extracorporeal Shockwave Treatment is an effective, FDA approved treatment. Extracorporeal shockwave treatment is not recommended for pregnant women, children, anyone with a pacemaker, anyone on anti-coagulant therapy or anyone with a history of bleeding problems.
Cancer pain can arise from many different causes, including the cancer itself, compression of a nerve or other body part, fractures or treatment of the cancer. There are many techniques to assist with treating the various pains from cancer, including medications and injections. In particular, medical destruction of nerve tissue (ablative therapies) and the use of pumps surgically placed into the body to deliver pain medication into the subarachnoid space can be used. Pain pumps deliver medication that is targeted to pain receptors on the spinal cord. The advantage to the cancer patient is chronic pain control with decreased side effects.
Pain Management Resources
Medically reviewed by Joseph Carcione, DO; American Board of Psychiatry and Neurology
"Overview of the Treatment of Chronic Non-Cancer Pain." UptoDate.com. Updated Aug. 15, 2016.