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Malignant peripheral nerve sheath tumor (MPNST) is a rare and aggressive soft tissue sarcoma and it is well known for its high local recurrence rate and poor prognosis. Complete resection with adequate surgical margin is the mainstay of treatment; this aggressive surgical procedure can lead to morbidity. Various techniques have been developed to restore thumb opposition in thenar muscle palsy using tendon transfer for opponenplasty, typically after failed nerve repair attempts and prolonged thumb dysfunction. Recently, distal nerve transfers have shown promise in restoring thumb motor function by reducing the distance for axon regeneration, thereby improving the chances of motor nerve recovery before muscle atrophy occurs.

We report a case of a 49-year-old female who underwent median nerve reconstruction with sural nerve graft combined with distal nerve transfer, in accordance with the technique employed by Bertelli et al. which involves transferring the motor branch of the abductor digiti quinti (ADQMB) to the thenar branch of the median nerve (TBMN) immediately after performing a wide resection of the MPNST of the median nerve in a single-stage operation.   

• At 2 months after surgery, the patient was able to do thumb opposition and active flexion of the index to little fingers.  
• At the 6-month follow-up visit, the patient had thumb IP flexion and index flexion grade 3 on the medical research council (MRC) motor power scale. She still had numbness at 3 radial digits, but she showed no evidence of thenar muscle atrophy. 
•  At 10 months post-surgery, her affected thumb opposition was grade 4 on the MRC muscle power scale. The grip strength of her affected thumb was 8 pounds compared with 16.5 pounds on the contralateral side. The Kapandji score of her affected thumb was 8, and she was able to use her hand for daily activities, including writing. She had decreased sensation of the median nerve distribution compared to the contralateral side. She had equal little finger abduction for both sides but MRC grade 4 on the affected side 
  

Distal nerve transfer is a good choice for reducing the time required for distant nerve regeneration. We would suggest transferring the ADQMB to the TBMN as early as possible in high-level median nerve injury or large defect gaps, as it is more practicable by virtue of the fact that the two nerves are close, and the ADQMB is expendable, having no function deficit after transfer.