If you’ve ever had an amputation, you might have experienced something called ‘”phantom limb pain”, which is pain that is felt in the missing part. The limb is gone, but the pain is real. It is most commonly felt after amputation of a part of an arm or a leg, but it can also be felt in other areas of the body that may have been removed, such as a breast and eye. As many as 80% of the amputee population worldwide has experienced some kind of phantom sensation in their amputated parts.
There is another kind of pain called the residual pain. while phantom pain appears in the body part that is no longer present, residual pain is felt near the site of amputated part that still exists; like for e.g., if the forearm is removed, pain can persist near the elbow.
Phantom pain is described as burning, throbbing, pins and needles or like an electric shock. Whereas, phantom sensations can be either painful or non-painful. the non-painful sensations include itching in the absent part, movement of the amputated limb or feeling of touch or temperature.
The causes of phantom limb pain are unclear but certain possible causes have been stipulated which include:
Rewiring of the nervous system : After a limb is amputated, the brain does not receive signals for that amputated part anymore, hence the bunch of neurons that used to receive signals for the now amputated part reorganize, but the pain that was perceived prior to the amputation remains.
The remaining nerves in the stump grow and form neuromas. These neuromas generate impulses which is perceived as pain.
The removal of a body part damages some peripheral nerves. This can cause overexcitation and irritation in the nerves causing pain. This can also cause central sensitization due to increased neural activity and sensitivity.
Diagnosis:
Your health care provider will perform physical examination to rule out infections and residual pain. To do that, some blood tests and ultrasound scan may be recommended.
Treatment:
There is no one treatment that works for everyone. you need to work with your pain specialist to try multiple options that can help relieve your pain.
- There are certain over-the-counter pain relievers that can help.
- Tricyclic antidepressant drugs can help with the nerve pain and also the psychological aspect of losing a limb.
- Anticonvulsant medications like gabapentin may be prescribed.
- Sympathetic nerve blocks : They are both a diagnostic and a therapeutic tool. a thin needle targeting the sympathetic nervous system is inserted under ultrasound guidance and a small amount of local anesthetic is injected to block the nerves. the pain relief experienced with this can be immediate and dramatic.
- Radiofrequency ablation, where radio waves are utilized to block the pain producing nerves.
- Cryoablation – Similar to radiofrequency ablation but cold temperatures are applied instead of radio waves.
- Spinal cord stimulation : The technology utilized here is similar to that of cardiac pacemakers. electrodes placed into the spinal cord produce small electric currents, thereby inhibiting pain transmission.
