Phantom limb pain after amputation is neurobiologically mediated primarily by which mechanism?

• A Stump neuroma formation at the cut nerve end causing nociceptive signals
• B Cortical reorganization (maladaptive neuroplasticity) in the somatosensory cortex with ectopic discharge from dorsal horn neurons ✓
• C Sympathetic efferent firing causing vasoconstriction in the residual limb
• D Myofascial trigger points in the ipsilateral paraspinal muscles

Explanation

Phantom limb pain involves both peripheral (stump neuroma, ectopic discharge from injured afferents) and central mechanisms. The dominant current understanding emphasizes maladaptive cortical reorganization — the cortical representation zone of the amputated limb is invaded by adjacent cortical areas, generating aberrant sensory signals perceived as painful phantom sensations. Ramachandran's mirror box therapy exploits visual feedback to normalize this cortical reorganization. Central sensitization with ectopic dorsal horn activity also contributes. Treatment options include mirror therapy, EMDR, amitriptyline, gabapentinoids, and ketamine infusions targeting central sensitization.

Reference: Maheshwari Essential Orthopaedics, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.