1/7/2022
Phantom limb pain, phantom sensation, and residual limb pain By Luke Kung’u The feeling of wholesomeness is the aspiration of any living thing and more so for human beings who can express their feelings more elaborately. Pain is the unpleasant but unavoidable circumstance that is brought by the loss of someone or something that one has an attachment with, and it affects the way we act and think. To someone else, pain may not be perceived to be a bother, but it is everything to the bearer. Now come to think of losing a body part that one has had for the greatest part of their lives. This is what amputees face as some of their body parts are taken away. It is nightmarish, to say the least. The fact that real pain can be experienced while the body part is missing is food for thought. It is a reality shrouded in mystery. Newsline engaged Senior Assistant Orthopedic Technologist, Mr. Damiano M. Mwangi, to unravel the secrecy that is ‘phantom pain’; and this is what he had to say. Read on: Q. Kindly differentiate between Phantom limb pain, Phantom sensation, and residual limb pain. A phantom limb is a vivid perception that a limb that has been removed or amputated is still present in the body and performing its normal functions. Amputees usually experience sensations including pain in the absent limb. Phantom sensation: Resembles the somatosensory experience of the physical limb before amputation, including warmth, itching, sense of position, and mild squeezing. That is, the patient perceives sensation in a severed body part. Changes occur in both the central nervous system and peripheral nervous system after an amputation that depends on the subsequent reorganization of the primary somatosensory and motor cortices of the brain. Residual limb pain: this is when the phantom sensations become intense enough for the amputee to
define them as pain. It is a complex poorly understood pain syndrome that is described as burning, aching or electric type pain in the amputated limb. Q. What symptoms are exhibited in such pain? Patients suffering from phantom limb pain perceive that the amputated limb is still present and functioning as usual. In many cases, these patients will experience a wide range of sensations in the phantom limb, some of which include: • A tickling feeling • Cramps • A shooting, piercing or stabbing pain • Numbness • Cold • Warmth • Tightness • Itchiness Q. What causes the pain? There are numerous theories about the causes of phantom limb pain including peripheral, central, and spinal theories: Peripheral Theories: Remaining nerves in the stump grow to form neuromas, which generate impulses. These impulses are perceived as pain in the limb that has been removed. Central nervous system: Melzack proposed that the body is represented in the brain by a matrix of neurons. Sensory experiences create a unique neuromatrix, which is imprinted on the brain. When the limb is removed, the neuromatrix tries to reorganize, but the neuro signature remains due to the chronic pain experienced before the amputation. This causes phantom limb pain after amputation.
PHOTO|COURTESY: Pain pathway in the dorsal horn
ISSUE 14 | Kenyatta National Hospital Newsline
Spinal theories: When peripheral nerves are cut during amputation, there is a loss of sensory input from the area below the level of amputation. This reduction in neurochemicals alters the pain pathway in the dorsal horn.
PHOTO | neurosciencenews Individual experiencing Phantom
Other related causes: Residual limb pain is believed to be caused by Ischemia, infections before amputation, neuroma, and pressurerelated wounds. Psychological factors such as stress and depression also influence the development of chronic phantom limb pain. Q. How is the pain diagnosed and managed in a hospital as well as at a home set-up? The residual limb pain is diagnosed through carrying out clinical examination (patient assessment) procedures that include; patient history, clinical examination, clinical investigations, and differential diagnosis among others. Various pain management strategies have been used including: • Peripheral Sensitization: Irritant management with attention to excluding differential diagnosis, poor wound dressings, stump oedema. • Pharmacology (Follow the pain
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