Phantom limb pain (PLP) and scar hyperalgesia (SH) are frequent problems after amputation; in particular most persons who undergo limb amputation will experience phantom pain. The neuropathic nature of PLP suggests the involvement of both peripheral and central neurological mechanisms, including neuroplastic changes in the central nervous system. PLP as other central nervous system-related pain syndromes remains a challenge for treatment. Scar hyperalgesia involves peripheral mechanisms and results frim the production of substances liberated by damaged skin cells. These inflammatory substances lower the pain threshold by altering the chemical environment of skin nerve endings. Scan hyperalgesia is associated with secondary mechanical hyperalgesia in the skin area around the scar. The lidocaine patch 5% is a topical analgesic acting by blocking sodium channels of peripheral nerve endings and by inhibiting ectopic discharges in sensitized and hyperactive cutaneous nociceptors. The patch is noninvasive, with minimal systemic absorption resulting in a reduced risk of drug-drug interaction. In addition, a central analgesic effect of lidocaine has been suggested. The lidocaine patch 5% is currently licensed for the treatment of symptomatic postherpetic neuralgia. It also has been successfully used in patients with other neuropathic pain states, such as entrapment neuropathies, painful idiopathic distal sensory polyneuropathies and postoperative/post traumatic neuropathic chronic cutaneous pain. The lidocaine patch has not been studied for the management and prevention of phantom limb pain. The aim of the present research is to investigate if a lidocaine patch 5% is effective for reducing PLP and primary/secondary scar hyperalgesia. The hypothesis is that persistent peripheral nociceptive input from the stump after surgery may drive maladaptive cortical reorganization leading to chronic central pain and thus promote chronic phantom limb pain. Treating scar hyperalgesia on the stump with topical lidocaine may reduce the activity of peripheral nociceptive afferents and thus decrease the likelihood of developing persistent phantom limb pain. This study is designed as a randomized controlled multicentric double blind trial, in which the effectiveness of applying a 5% lidocaine patch for 6 weeks will be compared with a sham.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
DOUBLE
CHU Brugmann - Queen Astrid
Brussels, Belgium
Erasme -CTR
Brussels, Belgium
Patient-reported overall daily pain intensity
The overall daily pain intensity (stump, scar and phantom pain combined) will be rated on a 0 to 100 visual analogue scale with anchors of 0 (no pain) to 100 (worst pain ever experienced).
Time frame: Daily, starting seven days before patch placement (baseline) till six weeks after patch placement
Neuropathic Pain (DN4)
Screening for neuropathic pain, by using the DN4 questionnaire
Time frame: at baseline - 7 days before patch placement
Neuropathic pain
Rated with the Neuropathic Pain Symptom Inventory
Time frame: at baseline - 7 days before patch placement
Neuropathic pain
Rated with the Neuropathic Pain Symptom Inventory
Time frame: One day after patch placement
Neuropathic pain
Rated with the Neuropathic Pain Symptom Inventory
Time frame: 6 weeks after patch placement
Neuropathic pain
Rated with the Neuropathic Pain Symptom Inventory
Time frame: 6 months after patch placement
Pain (McGill)
Rated by the Short-Form McGill Pain Questionnaire, sensitive to the effects of pain treatment.
Time frame: at baseline - 7 days before patch placement
Pain (McGill)
Rated by the Short-Form McGill Pain Questionnaire, sensitive to the effects of pain treatment.
Time frame: One day after patch placement
Pain (McGill)
Rated by the Short-Form McGill Pain Questionnaire, sensitive to the effects of pain treatment.
Time frame: 6 weeks after patch placement
Quality of life
Rated by the SF36 questionnaire
Time frame: at baseline -7 days before patch placement
Quality of life
Will be rated by the SF36 questionnaire
Time frame: six weeks after patch placement
Quality of life
Will be rated by the SF36 questionnaire
Time frame: six months after patch placement
Sleep quality
will be assessed with the Pittsburgh Sleep Quality index
Time frame: baseline -7 days before patch placement
Sleep quality
will be assessed with the Pittsburgh Sleep Quality index
Time frame: 6 weeks after patch placement
Sleep quality
will be assessed with the Pittsburgh Sleep Quality index
Time frame: 6 months after patch placement
Delay of dress of provisory prosthesis
Number of days between surgery and delivery of temporary prosthesis
Time frame: From the day of the surgery till the day of the delivery of temporary prosthesis, for a maximum of 6 months
Delay of dress of provisory prosthesis
Number of days between inclusion in the research protocol and delivery of temporary prosthesis
Time frame: From the day of patient inclusion in the research protocol till the day of the delivery of temporary prosthesis, for a maximum of 6 months
Cumulative analgesic consumption (morphine equivalents)
Rated by the cumulative analgesic consumption score (CACS)
Time frame: baseline -7 days before patch placement
Cumulative analgesic consumption (morphine equivalents)
Rated by the cumulative analgesic consumption score (CACS)
Time frame: 1 day after patch placement
Cumulative analgesic consumption (morphine equivalents)
Rated by the cumulative analgesic consumption score (CACS)
Time frame: 6 weeks after patch placement
Phantom Limb Pain occurence
occurence of phantom limb pain
Time frame: 6 months after patch placement
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