Phantom Pain and Methods of Management – Part 1

Have you heard of phantom pain? It is most commonly described as pain recognised from the brain and spinal cord due to a missing limb or part of the body, as if it is still attached. To get more scientific into phantom pain, the somatosensory and motor cortex areas of the brain reorganise itself to decrease the presentation of the missing limb in the cortical homunculus. This is the “map” of physical features of the body for sensory and motor functions. The size of each section in the body varies person to person, but most commonly the hands and face are the largest areas in the map. Phantom pain can be associated with the cortical representation in the brain – the larger the cortical representation of the missing limb, the more intense the phantom pain. Please see the cortical homunculus map below – blue is the sensory map, and red is the motor cortex map.

People that experience phantom pain recognise their missing limb in lifelike detail. An example of this is a missing hand; “they can flex their fingers and sometimes feel the chafe of a watchband” (TED-Ed, 2018). Phantom pain can be described as an intermittent or continuous stabbing, squeezing and crushing pain. A study conducted by Darnall and colleagues (2005) concluded that out of 914 persons with an upper limb amputation – 64% of participants found the phantom pain “bothersome”, and 21% of participants found phantom pain “severely bothersome”. Although, this is a small study, it emphasises that 50-80% of amputees have experienced phantom pain. The statistics of amputees is rising in recent years, as there are more military conflict injuries and increasing prevalence of metabolic diseases requiring amputation, such as diabetes.

Methods of Management – Mirror Therapy

People that have an amputated limb may be recommended from their health professional, such as an Accredited Exercise Physiologist, to use to mirror therapy as a method of pain management. Mirror therapy assists by using the intact limb to reflect an image on the mirror, or mirror box, to provide an illusion that two intact limbs exist. This is mostly used for upper limb amputations, although can be used with lower body amputations with a large mirror. This may cause cortical restructuring of the missing limb in the cortical homunculus to converge visual and proprioceptive input. The purpose of mirror therapy is to decrease pain amplification, although this does not work in some cases.

Therefore, other methods of phantom pain management are used such as education and exercise by Accredited Exercise Physiologists, which will be covered in Part 2. Stay tuned!

Emma Tutty (B.Sc. Exercise, Sports, & Rehab Science; Grad Dip. Exercise Physiology)
Accredited Exercise Physiologist (AES, AEP) (ESSAM)

 

References

Darnall, B. D. (2009). Self-delivered home-based mirror therapy for lower limb phantom pain.

American journal of physical medicine & rehabilitation/Association of Academic Physiatrists, 88(1), 78.

Darnall B. D., Ephraim P., Wegener S. T., et al. (2005). Depressive symptoms and mental health

service utilization among persons with limb loss: Results of a national survey. Arch Phys Med Rehabilitation, 86, 650–658.

Hu, L. (2016). Functional reorganization of the primary somatosensory cortex of a phantom limb pain

patient. Pain physician, 19, E781-E786.

Phantom Limb Pain. (n.d.). Retrieved from: https://www.painmanagement.org.au/using-

joomla/extensions/components/content-component/article-category-list/190-phantom-limb-pain.html

Ted-Ed. (2018). The fascinating science of phantom limbs. TED Education.