Silas Weir Mitchell, a prominent19th century Philadelphia physician, first coined the phrase "phantom limb" following the Civil War. Gangrene was a common result of battle injuries, and without antibiotics, surgeons sawed infected limbs off thousands of soldiers. These men returned home from war with phantom pain, setting off speculation among doctors as to its cause. Weir Mitchell published the first article on the topic under a pseudonym so as to not risk facing ridicule from his colleagues.
Since Weir Mitchell's time all types of conjecture regarding phantom pain, ranging from the sublime to the ridiculous, has been printed. As recently as 15 years ago, a paper in a Canadian psychiatry journal stated that phantom limb sensation is merely the result of wishful thinking. The authors argued that patients desperately want their limbs back, so therefore, experience the phantom.
A more popular explanation for phantom sensation is that the frayed and curled-up nerve endings in the residual area tend to become inflamed and irritated, thereby fooling higher brain centers into thinking that the missing limb is still there. Though there are far too many problems with this nerve irritation theory, because it's a simple and convenient explanation, many physicians cling to it today.
A Patient's Perspective
Despite what is said about phantom pain and sensation, patients who suffer adamantly argue that it's not in their "head." It's real pain — often so severe that even morphine-laden drugs don't offer relief. For some, years pass without a solid night's sleep.
Some patients say the pain they felt in their limbs immediately before amputation persists as a kind of pain memory. For example, soldiers who have grenades explode in their hands reported that their phantom hand is in a fixed position, clenching the grenade, ready to toss it. The pain in the hand is excruciating — the same they felt the instant the grenade exploded.
One woman in England suffered severe frostbite on her thumb as a child. Gangrene developed and the thumb had to be amputated. Now, 50 years later, she reports having chilblains (a frost-like pain due to cold weather) in her thumb when the weather turns cold.
A girl born without forearms experienced phantom hands six inches below her residual arms. She reported using her phantom fingers to calculate arithmetic problems.
Today, thousands of such stories have the medical profession, unlike in Weir Mitchell's day, acknowledging what these people feel is real — and often debilitating. A large group of doctors even specialize in phantom pain and sensation. Their hope is that research will help thousands of people around the world to enjoy pain free lives.
What Physicians Know Now
David R. Del Toro, M.D., is a specialist who works in the Department of Physical Medicine & Rehabilitation at the Medical College of Wisconsin in Milwaukee, Wisconsin. He has researched, studied and treated patients with phantom pain for more than 20 years, and is credited with dozens of articles published in medical and consumer journals. "The basis of my expertise with phantom pain is taking care of patients with all types of amputations," he says. "Approximately 10 percent of patients I see have had upper limb, and 90 percent have lower limb amputations."
Del Toro says from a research basis, the etiology of the mechanism of phantom pain causes aren't known. "We feel it's multi-factorial," he says. "As clinical research continues, we in the field continue testing treatments to help relieve the pain patients experience."
Some medications, according to Del Toro, offer promise. "One, generically named gabapentin, was marketed in the mid-1990s as an anti-seizure medication," he continues. "However, it's found helpful in offering relief for phantom pain. It's believed effective because it works on nerves, and consequently neuropathic pain. Today, more than 40 percent of prescriptions for the drug are for pain control, rather than seizure. It's also well accepted because it has less side effects than other pain drugs."
Del Toro acknowledges the widespread use of antidepressants for phantom pain today, but says he'd rather see an effective short-term drug developed. "Antidepressants have to be taken daily and over a long time period," he says. "Anytime patients are put on medicine indefinitely they must be monitored constantly to ensure the patient doesn't suffer with severe side effects or toxicity. A short-term treatment that's effective in offering relief is truly the preferred goal for phantom pain sufferers."
Educating The Patient Is Imperative
Del Toro says he looks for two keys in determining preferred treatment. "Those who have a sleep disturbance caused by the pain, and those whose pain impairs their ability to wear their prosthesis," he says. "A prosthesis seems to help relieve pain for most patients, and we find a definite correlation between the amount of time it's worn and the intensity of pain. Time also is a great healer. Many patients report their pain dissipated over time, while others become accustomed to it."
Preoperative consultation, Del Toro says, also is imperative to the best possible results regarding pain. "I tell them exactly what to expect," he says. "They'll have two kinds of pain following the amputation procedure — residual limb and phantom pain. Therapy begins as soon as possible following surgery, including massage desensitization. An elastic shrinker, a sock that applies gradient pressure, is placed on the residual limb to help overload the sensory input to the brain."
Although a radical difference exists between the level of pain patients feel, Del Toro says most need a low dose of medication to help them sleep for at least a short time following surgery. "Because we tell them everything that Ôcan' happen, their anxiety level is lessened before surgery," he says. "Studies show that stress adds to the level of pain, and educating the patient helps reduce it," he says. "It's also important to let them know that the pain they feel is real — not in their head. For now, and until research offers us improved treatment techniques, it's a matter of managing the problem rather than curing it. We just don't understand phantom pain enough to put an end to it. The first goal, therefore, is to help patients restore their functions and reach a gainful quality of life."
Not In Your Head
Richard A. Sherman, Ph.D., is the chief consultant for Orthopedic Research at Madigan Army Medical Center in Tacoma, Wash. He has researched and evaluated phantom pain causes and treatments for more than 30 years, and has written several books on the topic. His research reveals approximately 80 percent of people with amputations feel phantom pain — but a small majority of this group have it severely and on a continual basis. Most suffer slight pain, and only some of the time. He says it's crucial that people understand why they experience this pain. "If they believe they're having psychological problems, rather than real pain, it increases their level of distress," he says. "This, in turn, intensifies their pain. Phantom pain is a very normal sensation, and patients must be made to realize it."
Sherman offers an example of how our brains are wired: " The brain has a Ôpicture' of all the body parts," he says. "Every sensation that occurs in the body is carried to that image in the brain. This is how your conscious knows what part of you has been touched. If you touch your big toe — the image of the toe in the brain lights up. The conscious part of the mind, however, has no idea where the signals are coming from. Let's say you hit your funny bone. You feel pain at the elbow, but also down the arm and in your hand — but you didn't hurt those parts. The nerve gathering the information from the arm, forearm and hand has passed to the brain. In short, those parts of the brain light up so you feel you've been touched in those areas. If your arm was amputated somewhere between the forearm and elbow, then you hit your elbow — you'd still feel pain in your hand — even though it's missing — because the image in your brain is still there."
The level and intensity of phantom pain does change somewhat after amputation, according to Sherman, but for many people it never dissipates completely. "Anytime the nerves are used that stimulate those pictures in the brain, some level of sensation will occur," he says. "However, phantom pain is indeed different for everyone. We've conducted research using more than 12,000 people with amputations, and find there is no pattern to whether phantom pain will fade or not — or to what level. Some people don't even have it until many years after their amputation procedure."
More Than One Type Of Pain
Sherman says people with amputations report two typical types of phantom pain. "A burning and tingling sensation is common and attributed to decreased blood flow in the residual limb," he continues. "As circulation decreases due to age, medicines, inactivity or other reasons, these sensations tend to increase. We generally treat this with medications or biofeedback.
"Muscle tension causes the other type of pain. If spasms occur, people experience cramping type pain. Generally, the more severe the cramps, the more severe the pain. The cramps are usually very fast and spasmodic — a high frequency muscle spasm, unlike a Charlie horse. Treatment includes cramp-reducing drugs, or muscle tension biofeedback."
Depression, Sherman agrees, increases phantom pain, and he, too, recommends antidepressants be used only until alternative treatments are found. "Phantom pain is a 'referred pain' phenomena," he says. "You can give the patient a surface 'fix', or you can attack the mechanism. Once the mechanism is destroyed, the phantom pain is eliminated and the need for daily medication stops."
Sherman treats about 50 people with amputations annually."We help most people to at least some extent," he reports. "About 90 percent report that following therapy they no longer have the severe pain they once did. However, only 50 to 60 percent are cured completely. It's important to know that if medications and biofeedback don't help, it's likely because of a severely decreased blood flow caused by a condition, such as hardening of the arteries. We have little success with these patients. Nor do we understand the mechanisms of shocking treatments — like electric charges, and find there's little success in that area. One problem that continues to impede the progress in this area is that no two people experience the same type or intensity of pain — so there isn't a 'pill' that works for all. Each patient requires treatment based on what they experience."
Levels Of Therapy For Severe Cases
Todd Kuiken, M.D., Ph.D., works in biomedical engineering at the Rehabilitation Institute of Chicago (RIC), and is the director of amputee services for the institute. He also is an assistant professor at Northwestern University Medical School in Chicago, Ill. Kuiken sees an average of 150 new patients with amputations annually. He says almost everyone who has an amputation has phantom limb sensation. "Some patients wake up after surgery and report that their missing toes and fingers are moving," Kuiken says. "Some tell us they like the sensation because it helps them walk with their prosthesis. Other times they say it's annoying. Some even report radically unusual feelings — like their foot is on backwards. In one case, a woman's arm was laid across her chest as she was rushed to the emergency room. After the amputation she felt the arm still lying on her chest. It's important to use caution when asking the patient if they're having sensation after surgery. We don't want to put the idea of pain in their mind if it's not already there."
Despite what literature says about phantom pain, Kuiken says an extensive difference exists in the percentage of people who feel it, and its severity. "We find between 10 and 20 percent of patients request medication for their pain," he says. "They sometimes feel shooting, stabbing or cramping, and often it's the same as what they felt prior to amputation. With most patients, the level of pain decreases over time, usually after the first few months, but a percentage suffer long-term pain."
For this reason, Kuiken changes treatment over time. "For the first few months treatments include desensitization techniques; tapping, rubbing, friction and massaging the residual limb," he says. "Contrast baths — alternating from hot to cold water, is another treatment that works well. I prefer to try alternatives to medication first - but when the pain is intense enough to interfere with sleep or functioning, it's often required. Pain is subjective. Some people have higher pain tolerance levels than others — so each case must be evaluated individually. The patient must be told that the side effects of some medications can be worse than the pain itself. Neuropathic remedies, like antidepressants, are also effective, and tricyclic antidepressants are the best studied. They tend to make people sleepy, which can be good when taken at night; however, they also can cause palpitations, dry mouth and weight gain."
Kuiken says more difficult cases require tougher treatment. He works closely with Dr. Norman Harden, at the Center for Pain Studies at RIC, in many of these cases. "We use a comprehensive multidisciplinary approach, " he says. It includes psychotherapy, biofeedback, physical and occupational therapy to their maximum potential. This is done on a daily basis as an outpatient service. The length of treatment varies depending on the patient's severity of pain — and until results are reached. This program teaches people how to live with their pain and get on with life."
Physical Therapists Staying Abreast
Cathie Szemere, a physical therapist at HealthSouth Sunrise Rehab Hospital, in Sunrise, Fla., treats patients with all types of ailments, but she specializes in pain management for people with amputations. Szemere says most people with amputations come to the inpatient facility from acute care hospitals in South Florida.
"It's important to distinguish between phantom pain and sensation," Szemere says. "Phantom pain is difficult to manage because there's no clear-cut definition or cause. Some patients report cramping or burning, and others say they feel their missing limb is in an awkward position — such as twisted underneath their body. These sensations usually are experienced shortly after surgery. People who experience these sensations generally say it dissipates within weeks. Other's report their pain is constant or intermittent — from mildly annoying to intolerable."
Szemere says Ôgait' training — learning to walk — is beneficial because it enhances the perception and provides a sense of the limb's normal position in space. "This helps give the patient a sense of when the knee should be bent to take a step," she says. "It reduces phantom pain for some. Desensitizing by rubbing a terry cloth on the residual limb, tapping gently on body parts and hand-held massage units all help to decrease sensitivity. Residual limb swelling is another cause of pain. We apply compression with a shrinker, but in cases of severe swelling doctors sometimes use a rigid cast dressing. Swelling often continues unless a form of therapy reduces it. Using a prosthesis also helps eliminate swelling. Visualization techniques also help. We teach patients to close their eyes and visualize the missing limb is there — then pump the limb up and down."
Szemere also uses transcutaneous electrical nerve stimulation (TENS) for phantom pain treatment. "These are little electrodes that are moved over the skin," she continues. "Through trial and error we find where the slight current they provide offers the most relief. TENS helps to block the pain pathway to the brain so patients don't perceive it. It's a harmless apparatus, and patients can use it on their own. We like this treatment because it reduces the need for drugs. Trends in treatment today are moving away from medications — and we advocate as little use of drugs as possible, especially addictive pain pills. The key is to work with each patient individually to determine what works best for them."
Finally, Szemere says it's important to use caution in distinguishing between phantom pain and neuroma. "When the surgeon operates, a small ball forms on the end of the nerves," she says. "This causes pain in the residual limb that feels like an electrical current. We use an ultrasound treatment to decrease the inflammation in the area. Doctors sometimes inject analgesics with steroids into the residual. In severe cases, the surgeon has to go in and resect the nerve to another area to relieve the swelling responsible for the pain. If pain persists beyond these treatments, and before more aggressive treatment is tried, it's important to ensure that scar tissue, joint contractions, poor circulation and other physiological conditions aren't the cause of the pain. Above all, Szemere says it's imperative for patients to get as much psychological support as possible."
Looking Into a Future of Phantom Pain Relief
In recent years, Farabloc Development Corporation in British Columbia, Canada, has reported success with its proprietary fabric of woven nylon and fine metal fibers to help reduce phantom limb pain. In November 1993, the Canadian Journal of Rehabilitation reported that in a double-blind study using 34 sequentially randomized participants those using the Farabloc intervention reported complete, or near complete pain relief when using the garment, as compared to when they weren't wearing it. The study demonstrated that Farabloc does work for many amputees experiencing phantom limb pain, but not for every person — and it provides varying levels of pain relief.
Another treatment considered by some to be in the future investigation arena is Botox. This agent is derived from the bacterium, Clostridium Botulinum, and is known as Botulinum Toxin Type A. Botox is produced in controlled laboratory conditions and given in extremely small doses. Azad Bhatt, M.D., in Toms River, New Jersey, works in rehabilitation medicine, disability evaluations, electromyography and pain management. He explains that the brain sends electrical messages to the muscles so they can contract and move. "The electrical message is transmitted to the muscle by a substance called acetylcholine," he says. "Botox works to block the release of acetylcholine and, as a result, the muscle doesn't receive the message to contract. This means the muscle spasms stop or are greatly reduced, thereby providing pain relief."
Botox hasn't been tested in controlled environments or in studies on phantom pain, but Bhatt says it's reasonable to assume it will work with amputees the same way it works on others. "By injecting it into the residual area, the cramping and shooting pain would be elevated although the limb is missing," he says.
Dr. Del Toro says he prefers to stick with medically proven treatments. "We're looking at pregabulim, a local anesthetic steroid, for future hope," he says. Studies currently underway indicate this medication, now used preoperatively, may hold hope for phantom pain sufferers. Results, however, have been mixed. I am using it in cases where the patient doesn't respond to other techniques, but I'd like to see more research in this field before it's used as a common pain-relief agent."
Dr. Sherman says because most people find relief with today's treatments, he too will stick to proven applications. "It's important to help the patient find relief — regardless of how many techniques the doctor or therapist has to try," he says. "One thing is sure, pain is pain, and people who suffer with intense amounts of it will ultimately go elsewhere and try just about anything they think will offer them relief. The danger is that they may subject themselves to something that damages their body in another way."