Conditions: Amputation Phantom Limb Stump Pain
Keywords: pain phantom limb stump pain catheter nerve block peripheral nerve block NMCSD Post-Amputation Phantom Limb or Stump Pain
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 2
Healthy volunteers: no

Brief summary:
The purpose of this research study is to determine if putting local anesthetic-or numbing medication-through one or two tiny tube(s) placed next to the nerves that go to an amputated limb will decrease phantom limb and/or stump pain.

Detailed description:
Specific Aim 1: To determine if, compared with current standard-of-care treatment, the addition of an ambulatory continuous peripheral nerve block decreases post-amputation phantom limb and stump pain.

Hypothesis 1: Following upper or lower extremity amputation, phantom limb and/or stump pain will be significantly decreased four weeks following a multiple-day ambulatory continuous peripheral nerve block as compared with patients receiving standard-of-care treatment (as measured on the 11-point numeric rating scale).

Specific Aim 2: To investigate the possible relationship between the addition of a multiple-day ambulatory continuous peripheral nerve block to standard-of-care treatment of post-amputation phantom limb and/or stump pain and cortical reorganization.

Hypothesis 2: Following upper or lower extremity amputation with subsequent phantom limb pain/sensation and/or stump pain, the addition of a multiple-day ambulatory continuous peripheral nerve block to standard-of-care treatment will result in cortical reorganization during and four-weeks following the perineural infusion (as measured by MRI).

Arms:
arm 1: 3-7 days of perineural local anesthetic infusion arm 2: 3-7 days of perineural normal saline infusion

Interventions: intervention 1: perineural ropivacaine intervention 2: normal saline (placebo)
Intervention descriptions: intervention 1: ropivacaine 0.4%; the basal rate will be set at 7 mL/h intervention 2: the basal rate will be set at 7 mL/h

Protocol document: