Pain After Amputation
Three phenomena occur after amputation (i) phantom sensation, (ii) stump pain and (iii) phantom pain. While limbs are most commonly involved, the same problems can occur with teeth, breast and rectum. While Phantom sensation describes any sensation that is experienced in the absent part and are common after amputation, these are rarely a clinical problem as they are not painful.
A stump pain that persists after the stump has healed could be due to local pathology or due to the development of neuropathic pain process. Surgical revision of the stump site is only indicated when localized pathology is identified. Liaison with rehabilitation and limb-fitting services is very important. Where there is no obvious localized pathology,
it is best to avoid surgical revision of the stump and treat similarly to phantom limb pain.
Jumpy stump is defined as a movement disorder that occurs after limb amputation. It presents as involuntary myoclonic spasms, jerky or tremulous movements. This phenomenon frequently starts after a period of weeks or even months after the amputation procedure. It may or may not be associated with pain.
Phantom pain has been described in various terms (e.g.shooting, burning, cramping and aching) and is characteristically localized in the distal area of the phantom limb. In some amputees, the pain may be constant but of varying intensity. Others more commonly
experience intermittent episodes of high-intensity pain on a daily, weekly or less frequent basis. The duration of symptoms is unpredictable, resolving in months in a few amputees and persisting for decades in others.When phantom limb pain persists for longer than 6 months, the prognosis for spontaneous improvement is poor.
Management of Phantom pain
A multidisciplinary, multimodal approach is often necessary to improve pain and quality
of life in patients with phantom pain.
- Pharmacological - Apart from analgesic medicines like NSAIDs which are used in the initial postoperative phase, opioids are effective even for managing chronic neuropathic pain. Tricyclic antidepressants (e.g. amitriptyline) and anticonvulsants (e.g. gabapentin) have been shown to be effective in the management of neuropathic pain.
- Physical therapy - External heat and cold, ultrasound, transcutaneous electrical nerve stimulation, massage, adjustment of the prosthesis and manipulation of the stump have all been used with reported success.
Some patients experience involuntary movements in their phantom, such as a clenching spasm of the hand with the nails digging in to the palm. Mirror therapy is used under these circumstances.
- Psychological counselling - Explanation and reassurance, hypnosis, psychotherapy and cognitive behavioural therapy have all been shown to be successful in some circumstances.
- Pain interventions - Among the pain interventions, local administration of botulinum toxin is known to be effective in many patients with movement disorders in the stump along with pain. Sympathetic blocks and implantation of Spinal cord stimulator have been shown to decrease phantom limb pain in some cases.