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Objective: Contralateral C7 spinal nerve transfer is a useful operation for the treatment of brachial plexus root avulsion. The recovery of the independent function at the ipsilateral side, however, depends on neural circuitry reorganization in the central nervous system (CNS). This study tried to locate the CNS neuronal elements involved in the innervation of C7 spinal nerve.Method: Pseudorabies virus (PRV, TK/gG(-), 2 microlitre), which expressed green fluorescent protein (GFP), was injected into the left C7 spinal nerve in 20 adult Sprague Dawley rats. After rats survived for 6 h, 12 h, 24 h and 36 h, the C1-C7 segments of the spinal cord and brain were processed using a polyclonal immunohistochemical antibody against PRV.Results: PRV-labeled neurons were found mainly in gray matter of the C1-C7 segments of the spinal cord and at the following structures of the brain: lateral vestibular nucleus, lateral paragigantocellular nucleus, A5 cells, red nucleus, primary and secondary motor cortexes, primary and secondary somatosensory cortexes. Although located bilaterally, the PRV-labeled neurons existed predominantly in the ipsilateral side of the spinal cord and the contralateral side of the brain at 6-12 h after injection (p.i.). The number of PRV-labeled neurons in the CNS was increasing with rat's survival time and the distribution of these neurons turned bilateral with no obvious dominance to either side at 24 h and 36 h (p.i.).Conclusion: By use of transsynaptic tracing technique with PRV, the anatomically connected set of neurons, which modulates the activity of C7 spinal nerve, is located successfully in the CNS. [ABSTRACT FROM AUTHOR]

Objective: To investigate the compensative mechanism of no further impairment of the upper limb after ipsilateral C7 transfer for treatment of root avulsion of C5-C6 of the brachial plexus. Methods: Sixty Sprague Dawley (SD) rats were randomly divided into a C7-transection group and a control group, 30 rats each. In the C7-transection group, the left forelimbs of the animals underwent transection of ipsilateral C7 nerve root while C5 and C6 nerve roots were avulsed. In the control group, the left forelimbs only underwent C5 and C6 root avulsion. The representative muscles of C7 (innervated mainly by C7) including latissimus dorsi, triceps, extensor carpi radialis brevis and extensor digitorum communis were evaluated with neurophysiological investigation, muscular histology and motor end plate histomorphometry 3, 6 and 12 weeks after operation. The right forelimbs of all rats were taken as the control sides. Results: Three weeks after operation, the recovery rates of amplitudes of compound muscle action potential (CMAP) and CMAP latency, muscular wet weight and cross-sectional area of muscle fibers, and area of postsynaptic membranes of those four representative muscles in the C7-transection group were significantly lower than those of the control group (P <0.05 or P <0.01). Six weeks postoperatively, the recovery rates of CMAP amplitude and latency of the triceps showed no significant difference between the C7-transection group and the control group (P>0.05). For the extensor carpi radialis brevis and the extensor digitorum communis, the recovery rates of the cross-sectional area of muscle fibers, the amplitude and latency of CMAP and the area of postsynaptic membranes showed no significant difference between the two groups (P>0.05), while the rest parameters were still significantly different between the two gr o up (P <0.05 o r P <0.01). As far as the ultramic rostructure was concerned in the C7-transection group, more motor end plates of four representative muscles were observed and their ultramicrostructure also had a tendency to mature as compared with those of 3 weeks postoperatively. Twelve weeks after operation, all parameters of the C7-transection group were not significantly different from those of the control group (P >0.05). In the C7-transection group, the motor end plates were densely distributed and their ultramicrostructure in four representative muscles appeared to be mature as compared with those of the control group. Conclusions: After ipsilateral C7 transfer for treatment of root avulsion of C5-C6 of the brachial plexus, the nerve fibers of the lower trunk can compensatively innervate fibers of C7-representative muscles by means of motor end plate regeneration, so there is no further impairment on the injured upper limb. [Copyright &y& Elsevier]

We report a successful application of Oberlin's procedure combined with transfer of trapezius and latissimus dorsi with the teres major for reconstruction of elbow flexion as well as abduction and external rotation of the shoulder to a ten-year-old patient, who had a long defect of the left brachial plexus upper trunk caused by resection of the plexiform neuroma. [ABSTRACT FROM AUTHOR]

To compare the long-term results of transfers of the ipsilateral C7 (IC7) plus spinal accessory nerve (SAN) with those of triple nerve transfers (TNT) using one fascicle of the ulnar nerve to the biceps motor branch (Oberlin's procedure), SAN transferred to the suprascapular nerve, and transfer of the long head of triceps nerve branch to the anterior branch of axillary nerve to treat C5-C6 avulsion of the brachial plexus. The IC7 group included 9 patients undergoing transfers of IC7 to the upper trunk and SAN to the suprascapular nerve. Median age at surgery was 26 years and interval between injury and surgery was 2.8 months. Patients were observed for a median of 118 months. The TNT group contained 13 patients, median age 33 years; interval between injury and surgery was 3.1 months. Patients were observed for a median of 103 months. In the IC7 group, median shoulder abduction was 105° and median external rotation of the shoulder was 64°, which was similar to that of the TNT group (89° abduction and 58° external rotation). Eight of nine patients recovered at least M3 (Modified Narakas scale) strength of deltoid in the IC7 group, which was similar to that in the TNT group (11 of 13 patients). Six of nine patients achieved at least Medical Research Council grade 3 (MRC3) strength of biceps in the IC7 group, which was similar to that in the TNT group (11 of 13 patients). Of 4 patients in the IC7 group with a preoperative latissimus dorsi strength of MRC3 or less, 3 gained a deltoid strength of M3 or less, and 3 a biceps strength of MRC2 or less. Transfers of IC7 plus SAN provide results comparable to those of TNT for treatment of C5-C6 avulsion. Therapeutic IV. [ABSTRACT FROM AUTHOR]