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"See if you can reach out and grab this cup in your right hand. What are you feeling now?"
I feel my fingers clasping the cup."
"Okay try it again." (As the patient tries to reach for the cup, the doctor pulls it farther away)
"Ouch! Why did you do that?"
"Do what?"
"It felt like you ripped the cup right out of my fingers." (James Shreeve, June 1993)
In a normal situation, the patient would have had the cup pulled out of his hand. However, the patient, Fred Aryee, did not have his right arm; he lost it in a storm at sea. How is this possible? When Mr. Aryee lost his arm in 1983, he should not have any feelings after its loss. Yet in amputees, this condition, known as phantom limbs, is all too common. Oftentimes, the feelings that occur are simply ones of normal perception, but often, they are very painful, resulting in another condition called phantom pain.
SO WHAT IS A PHANTOM LIMB? Sometimes referred to as "stump hallucination": it is the subjective sensation, not arising from an external stimulus, that an amputated limb is still present.
Under our skin there are receptors for many sensations: light and deep pressure, movement, temperature and also for pain. Our pain receptors are free nerve endings resting in one of the layers of our skin called the Dermis, they detect any physical aversive stimulus. Once something has been detected, this message is then relayed through a nerve pathway to the brain. These receptors are located in all parts of our bodies, some parts, such as our fingers, contain many more than other areas; these extremities are more capable of localizing a stimulus. This concept is fairly straight forward - but how is it that a person can feel pain in their fingers, for example, when their hand has already been amputated? This is the concept of PHANTOM PAIN .There are a few major theories out at this time and we address these in class.
Sensations from an amputated limb can manifest themselves in many different ways, such as sensations of touch. For example, some amputees are able to feel their arm resting on a table, their fingers able to feel the texture of the table. Other times they can feel the absent limb in movement, possibly reaching for a glass. Some report that the limb is drastically deformed or forshortened, or that it remains rigid.
Sometimes, though, it is not merely a sensation that they feel, rather - pain. Frequent complaints are: tingling, prickling and shooting pains. Although this is not always the case. Some find themselves revisiting a pain they had previous to the amputation, such as an ingrown toenail. The pain is also not usually constant, some are reoccurring and others do not even begin until long after the surgery.
The popular notion is that a nerve is "something that hurts", this has only limited basis in fact. Most nerves do not hurt when they go into activity or are injured. But when you hurt yourself the basic disturbance consists of impulses in specific pain fibers and nerve centers. Embedded in our skin, for example, there are some three million "pain spots", regions which are a good deal more sensitive to pain than the surfaces immediately surrounding them.
The most minor mishap can start a series of events in the nervous system. When you stub your toe, the first thing that you seem to feel is a sharp pain that comes almost immediately. This is from the nerve impulses that travel along the fibers at amazing speeds, telling your brain to signal your foot to "pull away". So, you jerk your foot away without even thinking. In fact you react so quickly that the pain itself does not actually come until you have taken the emergency measures of removing your foot. In such cases you react first and feel afterwards.
Another sensation comes a bit later, the diffuse, burning kind of pain which may linger for a period of time. It is produced by a different, slower pathway. This sensation is reminding you to "take it easy for awhile", meaning favoring your toe for a bit.
