Extradural Contralateral Ventral Root Transfer to Treat Lower Limb Motor Dysfunction in Paraplegia

Study Design. Eight cadavers were included in this anatomical study. Objective. This study aimed to confirm the anatomical feasibility of extradural transfer of the contralateral T11 ventral root (VR) to the ipsilateral L2 level and the contralateral L1 VR to the ipsilateral L3 level to restore lower limb function in cases of paraplegia. Summary of Background Data. Motor dysfunction due to hemiplegia significantly affects the daily life of patients. To date, unlike in cases of upper limb dysfunction, there are few studies on the surgical management of lower limb movement dysfunction. Materials and Methods. Eight cadavers were included in this study to confirm the feasibility of the nerve transfer. After separating the VR and dorsal root at each level, the VRs at the T11 and L1 levels were anastomosed with the VRs of L2 and L3, respectively. The length of the VRs of donor roots and the distance between the donor and recipient nerves were measured. H&E staining was performed to verify the number of axons and the cross-sectional area of the VRs. Lumbar x-rays of 60 healthy adults were used to measure the distance between the donor and recipient nerves. Results. After exposing the bilateral extradural each root, the VRs could be easily isolated from the whole root. The distance between the VRs of T11 and L2, L1, and L3 was significantly longer than the length of the donor nerve. Therefore, the sural nerve was used for grafting. The measurements performed on the lumbar x-rays of the 60 healthy adults confirmed the results. The number of axons and cross-sectional area of the VRs were measured. Conclusion. Our study confirmed the anatomical feasibility of transferring the VRs of T11 to L2 and that of L1 to L3 to restore lower limb function in cases of hemiplegia.