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There are various types of sensations that may be felt:
- Sensations related to the phantom limb's posture, length and volume e.g. feeling that the phantom limb is behaving just like a normal limb like sitting with the knee bent or feeling that the phantom limb is as heavy as the other limb. Sometimes, an amputee will experience a sensation called telescoping. This is the feeling that the phantom limb is gradually shortening over time.
- Sensations of movement (e.g. feeling that the phantom foot is moving).
- Sensations of touch, temperature, pressure and itchiness. Many amputees report of feeling heat, tingling, itchiness, and pain.
Phantom pain involves the sensation of pain in a part of the body that has been removed.
Although not all phantom limbs are painful, people will sometimes feel as if they are gesturing, feel itches, twitch, or even try to pick things up. The missing limb often feels shorter and may feel as if it is in a distorted and painful position. Occasionally, the pain can be made worse by stress, anxiety, and weather changes. Phantom limb pain is usually intermittent. The frequency and intensity of attacks usually declines with time.
Some people who have undergone gender reassignment surgery have reported the sensation of phantom genitals. The reports were less common among post-operative transgender women, but did occur in transgender men. Similarly, subjects who had undergone mastectomy reported experiencing phantom breasts; these reports were substantially less common among post-operative transgender men, but did occur in transgender women.
A phantom limb is the sensation that an amputated or missing limb is still attached. Approximately 60 to 80% of individuals with an amputation experience phantom sensations in their amputated limb, and the majority of the sensations are painful. Phantom sensations may also occur after the removal of body parts other than the limbs, e.g. after amputation of the breast, extraction of a tooth (phantom tooth pain) or removal of an eye (phantom eye syndrome).
Although dysesthesia is similar to phantom limb syndrome, they should not be confused. In phantom limb, the sensation is present in an amputated or absent limb, while dysesthesia refers to discomfort or pain in a tissue that has not been removed or amputated. The dysesthetic tissue may also not be part of a limb, but part of the body, such as the abdomen. The majority of individuals with both phantom limb and dysesthesia experience painful sensations.
Phantom pain refers to dysesthetic feelings in individuals who are paralyzed or who were born without limbs. It is caused by the improper innervation of the missing limbs by the nerves that would normally innervate the limb. Dysesthesia is caused by damage to the nerves themselves, rather than by an innervation of absent tissue.
Dysesthesia should not be confused with anesthesia or hypoesthesia, which refer to a loss of sensation, or paresthesia which refers to a distorted sensation. Dysesthesia is distinct in that it can, but not necessarily, refer to spontaneous sensations in the absence of stimuli. In the case of an evoked dysesthetic sensation, such as by the touch of clothing, the sensation is characterized not simply by an exaggeration of the feeling, but rather by a completely inappropriate sensation such as burning.
Dysesthesia can generally be described as a class of neurological disorders. It can be further classified depending on where it manifests in the body, and by the type of sensation that it provokes.
Cutaneous dysesthesia is characterized by discomfort or pain from touch to the skin by normal stimuli, including clothing. The unpleasantness can range from a mild tingling to blunt, incapacitating pain.
Scalp dysesthesia is characterized by pain or burning sensations on or under the surface of the cranial skin. Scalp dysesthesia may also present as excessive itching of the scalp.
Occlusal dysesthesia, or "phantom bite", is characterized by the feeling that the bite is "out of place" (occlusal dystopia) despite any apparent damage or instability to dental or oromaxillofacial structures or tissue. Phantom bite often presents in patients that have undergone otherwise routine dental procedures. Short of compassionate counseling, evidence for effective treatment regimes is lacking.
Clinical features of CRPS have been found to be inflammation resulting from the release of certain pro-inflammatory chemical signals from the nerves, sensitized nerve receptors that send pain signals to the brain, dysfunction of the local blood vessels' ability to constrict and dilate appropriately, and maladaptive neuroplasticity.
The signs and symptoms of CRPS usually initially manifest near the site of a (typically minor) injury. The most common symptoms are pain sensations, including burning, stabbing, grinding, and throbbing. Moving or touching the limb is often intolerable. The patient may also experience muscle spasms; local swelling; extreme sensitivity to things such as wind and water, touch and vibrations; abnormally increased sweating; changes in skin temperature (usually hot but sometimes cold) and color (bright red or a reddish violet); softening and thinning of bones; joint tenderness or stiffness; changes in nail and hair growth and/or restricted or painful movement. Drop attacks (falls), almost fainting, and fainting spells are infrequently reported, as are visual problems. The symptoms of CRPS vary in severity and duration. Since CRPS is a systemic problem, potentially any organ can be affected.
The pain of CRPS is continuous although varies in severity. It is widely recognized that it can be heightened by emotional or physical stress.
Previously it was considered that CRPS had three stages; it is now believed that people affected by CRPS do not progress through these stages sequentially. These stages may not be time-constrained and could possibly be event-related, such as ground-level falls or re-injuries of previously damaged areas. Thus, rather than a progression of CRPS from bad to worse, it is now thought, instead, that such individuals are likely to have one of the three following types of disease progression:
1. "Stage" one is characterized by severe, burning pain at the site of the injury, muscle spasms, joint stiffness, restricted mobility, rapid hair and nail growth, and vasospasm. The vasospasm is that which causes the changes in the color and temperature of the skin. Some may experience hyperhydrosis (increased sweating). In mild cases this stage lasts a few weeks, in which it can subside spontaneously or respond rapidly to treatment (physical therapy, pain specialist).
2. "Stage" two is characterized by more intense pain. Swelling spreads, hair growth diminishes, nails become cracked, brittle, grooved and spotty, osteoporosis becomes severe and diffuse, joints thicken, and muscles atrophy.
3. "Stage" three is characterized by irreversible changes in the skin and bones, while the pain becomes unyielding and may involve the entire limb. There is marked muscle atrophy, severely limited mobility of the affected area, and flexor tendon contractions (contractions of the muscles and tendons that flex the joints). Occasionally the limb is displaced from its normal position, and marked bone softening and thinning is more dispersed.
Complex regional pain syndrome (CRPS), also known as reflex sympathetic dystrophy (RSD), is a long term pain syndrome that often worsens with time. It is characterized by severe pain out of proportion to the original injury and is often accompanied by sensitivity, swelling, and changes in the skin. It may initially affect one limb and then spread throughout the body; 35% of affected people report symptoms throughout their whole body.
The cause of CRPS is unknown though CRPS is associated with dysregulation of the central nervous system and autonomic nervous system resulting in abnormal temperature control and pain of the affected limb(s) resulting in functional impairment and disability. Precipitating factors include injury and surgery, although there are cases where no identifiable injury had occurred at the original site. CRPS is not caused by psychological factors, yet the constant pain and reduced quality of life are known to cause psychological problems (such as increased depression and anxiety). Although "research does not reveal support for specific personality or psychopathology predictors of the condition," CRPS is associated with psychosocial effects, including impaired social and occupational function. It is classified as an amplified musculoskeletal pain syndrome.
Treatment involves a multidisciplinary approach involving medications, physical and occupational therapy, psychological treatments, and neuromodulation. Despite this, the results are often unsatisfactory, especially if treatment is delayed.
Supernumerary phantom limb is a condition where the affected individual believes and receives sensory information from limbs of the body that do not actually exist, and never have existed, in contradistinction to phantom limbs, which appear after an individual has had a limb removed from the body and still receives input from it.
An fMRI study of a subject with a supernumerary phantom left arm was done by Khateb "et al." at the Laboratory of Experimental Neuropsychology at the University of Geneva. When the subject was told to touch her right cheek with the phantom limb, there was increased activity in the motor cortex of her brain in the area roughly corresponding to the left arm. When she announced that she had touched the phantom limb to her cheek, activity was monitored in the area of the somatosensory cortex that corresponded to the right cheek. At times during the experiment, the subject was asked to move the phantom limb to a location that was obstructed or otherwise unfeasible. In these instances, there was similar activation of the motor cortex but no such activity in the somatosensory cortex.
Obdormition (; from Latin "obdormire" "to fall asleep") is a medical term describing numbness in a limb, often caused by constant pressure on nerves or lack of movement. This is colloquially referred to as the limb "going to sleep," and usually followed by paresthesia, colloquially called "pins and needles".
Patients may experience numbness, prickling or tingling sensations (paresthesias), or the feeling a limb has "fallen asleep" (an indicator of nerve compression), burning, cutting or other sensations.
Certain types of seizures are associated with the somatosensory system. Cortical injury may lead to loss of thermal sensation or the ability to discriminate pain. An aura involving thermal and painful sensations is a phenomenon known to precede the onset of an epileptic seizure or focal seizure. Another type of seizure, called a sensory Jacksonian seizure involves an abnormal, localizable, cutaneous sensation but does not have apparent stimulus. This sensation may progress along a limb or to adjacent cutaneous body areas, reflecting abnormal neuronal firing in the postcentral gyrus where an epileptic discharge is propagated. These episodes in which patients are consciously aware during a seizure have been useful for identifying problems associated with the somatosensory cortex. Patients can describe the nature of the seizure and how they feel during it.
Somatoparaphrenia is a type of monothematic delusion where one denies ownership of a limb or an entire side of one's body. Even if provided with undeniable proof that the limb belongs to and is attached to their own body, the patient produces elaborate confabulations about whose limb it really is, or how the limb ended up on their body. In some cases, delusions become so elaborate that a limb may be treated and cared for as if it were a separate being.
Somatoparaphrenia differs from a similar disorder, asomatognosia, which is characterized as loss of recognition of half of the body or a limb, possibly due to paralysis or unilateral neglect. For example, asomatognosic patients may mistake their arm for the doctor's. However, they can be shown their limb and this error is temporarily corrected.
Somatoparaphrenia has been reported to occur predominately in the left arm of one's body, and it is often accompanied by left-sided paralysis and anosognosia (denial or lack of awareness) of the paralysis. The link between somatoparaphrenia and paralysis has been documented in many clinical cases and while the question arises as to whether paralysis is necessary for somatoparaphrenia to occur, anosognosia is not, as documented by cases with somatoparaphrenia and paralysis with no anosognosia.
Patient feels contracture of middle and ring finger. Slight thinning of the subdigital Palm of the affected fingers. Initial pain and weakness subside with preliminary treatment with antiinflammatories, and B-complex vitamins. Initial loss of function improves almost fully.
The symptoms of MMA usually progress slowly for one to two years before reaching a plateau, and then remain stable for many years. Disability is generally slight. Rarely, the weakness progresses to the opposite limb. There is also a slowly progressive variant of MMA known as O'Sullivan-McLeod syndrome, which only affects the small muscles of the hand and forearm and has a slowly progressive course.
Lameness is most commonly caused by pain, but may also be the result of neuromuscular disease or mechanical restriction. Lameness itself is a clinical sign, and not a diagnosis.
It has been suggested that damage to the posterior cerebral regions (temporoparietal junction) of the cortex may play a significant role in the development of somatoparaphrenia. However, more recent studies have shown that damage to deep cortical regions such as the posterior insula and subcortical structures such as the basal ganglia, the thalamus and the white matter connecting the thalamus to the cortex may also play a significant role in the development of somatoparaphrenia. It has also been suggested that involvement of deep cortical and subcortical grey structures of the temporal lobe may contribute to reduce the sense of familiarity experienced by somatoparaphrenic patients for their paralyzed limb.
Pseudoathetosis is abnormal writhing movements, usually of the fingers, caused by a failure of joint position sense (proprioception) and indicates disruption of the proprioceptive pathway, from nerve to parietal cortex.
Gluteal gait is an abnormal gait caused by neurological problems. If the superior gluteal nerve or obturator nerves are injured, they fail to control the gluteus minimus and medius muscles properly, thus producing an inability to tilt the pelvis upward while swinging the leg forward to walk. To compensate for this loss, the leg swings out laterally so that the foot can move forward, producing a shuffling or waddling gait.
Injury to the superior gluteal nerve results in a characteristic motor loss, resulting in a disabling gluteus medius limp, to compensate for weakened abduction of the thigh by the gluteus medius and minimus, and/or a gluteal gait, a compensatory list of the body to the weakened gluteal side.
As a result of this compensation, the center of gravity is placed over the supporting lower limb. Medial rotation of the thigh is also severely impaired. When a person is asked to stand on one leg, the gluteus medius and minimus normally contract as soon as the contralateral foot leaves the floor, preventing tipping of the pelvis to the unsupported side. When a person with paralysis of the superior gluteal nerve is asked to stand on one leg, the pelvis descends on the unsupported side, indicating that the gluteus medius on the contralateral side is weak or non-functional. This observation is referred to clinically as a positive Trendelenburg's sign.
When the pelvis descends on the unsupported side, the lower limb becomes, in effect, too long and does not clear the ground when the foot is brought forward in the swing phase of walking. To compensate, the individual leans away from the unsupported side, raising the pelvis to allow adequate room for the foot to clear the ground as it swings forward.
Lameness is an abnormal gait or stance of an animal that is the result of dysfunction of the locomotor system. In the horse, it is most commonly caused by pain, but can be due to neurologic or mechanical dysfunction. Lameness is a common veterinary problem in racehorses, sport horses, and pleasure horses. It is one of the most costly health problems for the equine industry, both monetarily for the cost of diagnosis and treatment, and for the cost of time off resulting in loss-of-use.
People with hemiparesis often have difficulties maintaining their balance due to limb weaknesses leading to an inability to properly shift body weight. This makes performing everyday activities such as dressing, eating, grabbing objects, or using the bathroom more difficult. Hemiparesis with origin in the lower section of the brain creates a condition known as ataxia, a loss of both gross and fine motor skills, often manifesting as staggering and stumbling. Pure Motor Hemiparesis, a form of hemiparesis characterized by sided weakness in the leg, arm, and face, is the most commonly diagnosed form of hemiparesis.
Depending on the type of hemiparesis diagnosed, different bodily functions can be affected. Some effects are expected (e.g., partial paralysis of a limb on the affected side). Other impairments, though, can at first seem completely non-related to the limb weakness but are, in fact, a direct result of the damage to the affected side of the brain.
Analogous to Romberg's sign, the abnormal posturing is most pronounced when the eyes are closed as visual inputs are unavailable to guide corrective movements. Paradoxically, eye closure may decrease the amount of movement as the visual cues probably trigger corrective movements which return the limb to the desired "baseline" allowing a new phase of involuntary drift before a subsequent corrective phase occurs.
Polymelia (from Greek πολυ- = "many" plus μέλος (plural μέλεα) = "limb") also known as "hydra syndrome" is a birth defect involving limbs (a type of dysmelia), in which the affected individual has more than the usual number of limbs. In humans and most land-dwelling animals, this means having five or more limbs. The extra limb is most commonly shrunken and/or deformed.
Sometimes an embryo started as conjoined twins, but one twin degenerated completely except for one or more limbs, which end up attached to the other twin.
Sometimes small extra legs between the normal legs are caused by the body axis forking in the dipygus condition.
Limb girdle syndrome is a term to describe several distinct medical conditions including polymyositis, myopathy associated with endocrine disease, metabolic myopathy, drug-induced myopathy and limb-girdle muscular dystrophy.
Limb girdle syndrome is weakness located and concentrated around the proximal limb muscles. There are many causes, manifestations and treatments.