Abstract

Supernumerary phantom limb (SPL) is a rare and complex neurological phenomenon characterized by the illusory perception of additional limbs without actual anatomical loss. While typically linked to central nervous system disorders such as stroke, spinal cord injury, and demyelinating diseases, its association with neuromyelitis optica spectrum disorder (NMOSD) has not been well-documented. A 61-year-old female patient was diagnosed with aquaporin-4 (AQP4) antibody-positive NMOSD following a varicella zoster virus infection. Her disease course was marked by longitudinally extensive transverse myelitis and retrobulbar optic neuritis. During inpatient rehabilitation, she developed SPLs emerging from both elbows. Her management included multimodal rehabilitation with gabapentinoids, transcutaneous electrical nerve stimulation and task-specific motor training. However, visual tactile feedback techniques were limited by her severe visual impairment. Despite persistent SPLs, upper limb function improved, with gains in motor function and activities of daily living. In conclusion, this unique case highlights a rare association between NMOSD and SPL, expanding the spectrum of body schema disturbances in demyelinating disease.

Citation: Tan LYC, Ng VZY, Tay MRJ. Supernumerary phantom limbs in a patient with neuromyelitis optica spectrum disorder and rehabilitation challenges: A case report. Arch ISPRM 2026;1(2):191-196. https://doi.org/10.5606/archisprm.2026.44.

L.Y.C.T., Z.Y.V.N., M.R.J.T.: Contributed equally to this manuscript and had full access to the above data; L.Y.C.T., Z.Y.V.N.: Participated in the writing of the paper; M.R.J.T.: Participated in the critical revision of the paper. All authors above take full responsibility for the integrity of the data and the accuracy of the data analysis.

The authors declare that there are no conflicts of interest with respect to the research, authorship, and/or publication of this article.

Data Availability
The datasets generated and/or analyzed during the current study are available from the corresponding author on reasonable request.

This research received no specific grant from any funding agency in the public, commercial, or not‑for‑profit sectors.

AI Disclosure
The authors declare that artificial intelligence (AI) tools were not used, or were used solely for language editing, and had no role in data analysis, interpretation, or the formulation of conclusions. All scientific content, data interpretation, and conclusions are the sole responsibility of the authors. The authors further confirm that AI tools were not used to generate, fabricate, or ‘hallucinate’ references, and that all references have been carefully verified for accuracy.

We would like to express our gratitude to the medical, allied health, and nursing staff of the rehabilitation center for their dedicated care and close observation of the patient.