A 30-year-old man with disabling phantom limb pain after a traumatic transtibial amputation is started on mirror therapy. The proposed mechanism by which mirror therapy relieves phantom limb pain is:
- A It desensitises the terminal neuroma through repeated mechanical stimulation
- B Visual feedback of a moving intact limb resolves the mismatch between motor output and absent proprioceptive input, driving cortical reorganisation ✓
- C It blocks nociceptive transmission at the dorsal horn via gate control
- D It reduces sympathetic vasoconstriction in the residual limb
Correct answer: B. Visual feedback of a moving intact limb resolves the mismatch between motor output and absent proprioceptive input, driving cortical reorganisation
Explanation
Mirror therapy, popularised by Ramachandran, uses the mirror image of the intact moving limb to substitute for missing proprioceptive and visual input from the amputated limb, resolving the conflict between motor commands and absent sensory feedback and promoting favourable cortical reorganisation. Neuroma desensitisation acts on stump pain rather than phantom pain, gate control applies to transcutaneous electrical stimulation, and sympathetic modulation underlies procedures like stellate ganglion block, not mirror therapy.
Reference: Campbell's Operative Orthopaedics, 14th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.