gms | German Medical Science

Objectives/Interrogation: To provide New modality for radial nerve palsy, we provide our experience on median-to-radial nerve transfer, especial the indication, choice of donor motor branch, technique tips.

Methods: We choose the patients of severe radial nerve palsy as the candidates for median-to-radial nerve transfer, including 1) proximal injury; 2) long nerve defect more than 8~10cm; 3) severe soft tissue injury. We treated 6 patients during 2008 to 2017, two proximal injuries and 4 long nerve defect.We transfered branch of Pronator teres (PR) to branch of extensor carpi radialis brevis (ECRB) and branch of flexor digitorum superficialis (FDS) of middle or ring finger to posterior interosseous nerve (PIN) in the first case, then changed the strategy into FDS-to-ECRB and flexor carpi radialis (FCR)-to-PIN. In operation, after identifying the main trunk and branches of median and radial nerve, the donor and receipt branches were indetified and freed as long as possible. Confirming again, the PIN and ECRB nerves were divided well proximally and FDS and FDS or PR as distal as possible, then coapted ends without tension. Positive exercises of joints were initiated 3 days postoperatively. Synergic exercises were started 3 mouths later. Once synergic movements achieved, independent movements were started.

Results and Conclusions: 2 patients reported numb in index and middle fingers and resolved within 4 weeks. The strength of FPS of middle or/and ring fingers were 4- in 3 patients and recovered to normal within 12 w. The strength of FCR decreased to 2 in 5 patients, 4- in 1 patient, which recovered to normal in 3 patients, and 4 degree in 1 patient within 6 m, and no recovery in 1 patient. The extensors regained their strength 3~6 m gradually, and achieved biggest strength 12~18 m. The strength of recovered muscles are 3+~5. The patients orderly regained their movements. The patients can extend their thumb, index and little fingers independently. The excursion of wrist and fingers were comparable to contralateral side, to gain full excursion, 3 patients had to finish the movement along with the corresponding donor movement. In conclusion, median-to-radial transfer is a effective to restore the motor function of radial nerve. We recommend using the synergic motor nerve for transfer. It will take long to achieve these functions and need effective rehabilitation to finish the cortical plasticity, but the patients can gain more independent and flexible movement and larger excursion compared to tendon transfer.