【Abstract】 Objective To investigate the feasibil ity of contralateral C7 nerve transfer via posterior spinal route fortreatment of brachial plexus root avulsion injury by anatomical study. Methods Ten cadaveric specimens of 7 men and3 women were selected, who had no obvious deformity and no tissue defect in neck neutral position. By simulating surgical exploration of brachial plexus injury, the length of contralateral C7 nerve root was elongated by dissecting its anterior and posterior divisions to the distal end, while the length of C7 nerve from the intervertebral foramen to the branching point and the length of the anterior and posterior divisions were measured. By simulating cervical posterior approach, the C7 vertebral plate and T1 spinous process were fully exposed; the hole was made near vertebral body; and the C7 nerve root lengths by posterior vertebra path to the contralateral upper trunk and lower trunk were measured. Results C7 nerve root length was (58.62 ± 8.70) mm; the length of C7 nerve root plus posterior or anterior division was (65.15 ± 9.11) mm and (70.03 ± 10.79) mm, respectively. By posterior spinal route, the distance was (72.12 ± 10.22) mm from the end of C7 nerve to the contralateral upper trunk of brachial plexus, and was (95.21 ± 12.50) mm to the contralateral lower trunk of brachial plexus. Conclusion Contralateral C7 nerve can be transferred to the contralateral side through posterior spinal route and it only needs short bridge nerve or no. The posterior spinal route can effectively prevent from neurovascular injury, so it might be the best surgery approach for the treatment of brachial plexus root avulsion injury.
Objective To observe the recovery of the sensory and motor function of the repaired l imb and the impact on the healthy l imb function after contralateral C7 nerve root transposition for treating brachial plexus root avulsion injury. Methods Between August 2008 and November 2010, 22 patients with brachial plexus root avulsion injuries were treated with contralateral C7 nerve root transposition. All patients were male, aged 14 to 47 years (mean, 33.3 years). Total brachialplexus root avulsion was confirmed by preoperative cl inical examination and electrophysiological tests. In 22 cases, median nerve was repaired in 16 cases, radial nerve in 3 cases, and musculocutaneous nerve in 3 cases; primary operation was performed in 2 patients, and two-stage operation was performed in 20 patients. The sensory and motor functional recovery of the repaired limb was observed after operation. Results Twenty-one patients were followed up 7-25 months (mean, 18.4 months). In 16 cases of contralateral C7 nerve root transposition to the median nerve, wrist flexors reached more than M3 in 10 cases, while finger flexors reached more than M3 in 7 cases; sensation reached more than S3 in 11 cases. In 3 cases of contralateral C7 nerve root transposition to the musculocutaneous nerve, elbow flexors reached more than M3 in 2 cases; sensation reached more than S3 in 2 cases. In 3 cases of contralateral C7 nerve root transposition to the radial nerve, wrist extensor reached more than M3 in 1 case; sensation reached more than S3 in 1 case. Conclusion Contralateral C7 nerve root transposition is a good procedure for the treatment of brachial plexus root avulsion injury. Staged operation is one of important factors influencing treatment outcome.
Objective To investigate the sensation of the fingers innervated by the brachial plexus roots and provide the theoretic basis for diagnosis of a brachial plexus injury. Methods From June 2003 to January 2005，10 patients (8 males, 2 females; age,18-47 years) with complete brachial plexus avulsion were involved in this study, who underwent thecontralateral C7 nerve root transfer. The latency and amplitude of the sensory nerve actiopotential(SNAP) were record at the C5 T1 nerve roots when stimulation was given at the fingers.Results When the thumb and the index finger were stimulated and SNAP was recorded at all the roots of the brachial plexus in all the patients, we found that there was a higher amplitude and a shorter latency at the C5-7 roots than at the C8 and T1 roots(P＜0.05). When the middle finger was stimulated and SNAP was recorded at the C7,8 and T1 roots, we found that there was the highest amplitude and the shortest laency at the C7 root(P＜0.01). When the ring finger was stimulated and SNAP was recorded at the C7,8and T1 roots, we found that there was a higher amplitude and a shorter latency at the C8 and T1 roots than at the C7 root(P＜0.01). When the little finger was stimulated and SNAP was recorded at the C7,8and T1 roots, we found that there was the highest amplitude and the shortest latency at the T1 root(P＜0.01). ConclusionThe sense of the thumband the index finger is mainly nnervated by the C5-7 roots, the middle finger sense is mainly innervated by the C7 root, the ring finger sense is mainly innervated by the C8 and T1 roots, and the little finger sense is mainly innervated by the T1 root.
Objective To investigate the survival effect and reaction mechanismsof motor neurons after reimplantation of the avulsed root into the spinal cord,and to observe the survival and differentiation in the spinal cord after brachial plexus roots avulsion. Methods Thirty adult Wistar rats were randomly devided into the control group and the experimental group (n=15). Laminectomy of C4-6 was performed via a posterior approach. The ventral and dorsal roots of C5，6 were both avulsed from the spinal cord outside the dura mater and within the vertebral canal.For the experimental group, the ventral root of C6 wasreimplanted into the ventralhorn under microscope. The dorsal root was left. The ventral and dorsal roots of C5 were placed inside the nearby muscles. For the control group, the ventral and dorsal roots of both C5 and C6 were placed inside the nearby muscles. At 2, 4, 6, 8, 12 weeks postoperatively, the C6 spinal cord was stained with HE. The changes of the number and morphology of motor neurons were observed onHEstained sections. The C6 spinal nerve root was stained with silver nitrate, andthe regeneration of nerve fiber was observed. Results All rats were recovered well and their wounds were healed at primary stage. The gross observation showed that the avulsed nerve roots in control group adhered to adjacent muscles, however the one in experimental groups which had been implanted into spinal cord adhered to scar tissues and were not separated from spinal cord. At each time point postoperatively, the HEstained transverse sections showed that the number of motor neurons decreased significantly with soma swollen and atrophied, Nissle bodies decreased or disappeared. The survival rates of motor neurons in the control group were 60.9％±5.8%,42.3％±3.5％,30.6％±6.1％27.5％±7.9％ and 20.4％±6.8％ respectively；in the experimental group,the survival rates were 67.1％±7.4％,56.3％±4.6％,48.7％±8.8％,44.2％±5.5％ and 42.5％±8.3％ respectively. The survival rates of motor neurons in the experimental group was higher than those in the control group at all time points,showing statistically significant difference（Plt;0.01）.At 12 weeks postoperatively, thesilver nitrate stained specimen from the C6 nerve root showed regeneration of the motor neurons in the ventral horn into the reimplanted nerve root through axon in the experimental group,but the degeneration of the nerve fiber appeared and the number of the myelinated nerve fiber decreased in the control group. Conclusion Through reimplantationof the avulsed ventral nerve root into the ventral horn, degeneration of the motor neurons in the ventral horn can be reduced. After reimplantation of avulsed nerve root, there is axonal regrowth of motor neurons into the spinal nerve root and regeneration of the myelinated nerve fiber also appears.
Objective To investigate the results of two stage multiple nerves transfer for treatment of complete brachial plexus root avulsion. Methods Eight patients with complete brachial plexus avulsion, aging 18-38 years andwith a mean 6 months interval of injury and repair, were surgically treated with the following procedures. One stage surgical procedure was that the contralateral C7 never root was transferred to the ulnar nerve, the phrenic nerve to theanterior division of upper trunci plexus brachialis and the accessory nerve to the suprascapular nerve. Two stage surgical procedure was that the ulnar nerve was transferredto the median nerve , the intercostal nerves to the radial nerve and the thoracodorsal nerve. Results All patients were followed upfrom 13 months to 25 months(21 months on average), muscle reinnervation was observed in all patients. Return of muscle power of M3 or better are regarded as effective. The effective recovery results were 75% in musculocutaneous nerve, 37.5% in suprascapular nerve, 37.5% in radial nerve, 75% in thoracodorsal nerve and 62.5% in median nerve. In sensory recovery of the median nerve, 4 patients obtained S3, 3 patients S2 and 1 patient S1. Conclusion Two stage multiple nerves transfer for treatment of root avulsion of brachial plexus can achieve better motor function results and is safe and effective. The procedure should be recommended for treatmentof root avulsion of brachial plexus in selected patients with complete brachial plexus root avulsion, especially in young patients with a short interval between injury and repair. It isone of the alternative options.
ObjectiveTo evaluate the methods and effectiveness of contralateral C7 nerve root and multiple nerves transfer for the treatment of brachial plexus root avulsion. MethodsBetween June 2006 and June 2010, 23 patients with brachial plexus root avulsion were treated. There were 20 males and 3 females, aged 17 to 42 years (mean, 27.4 years). The time from injury to operation was 4 to 12 months (mean, 5.9 months). In 16 patients having no associated injury, the first stage procedure of contralateral C7 nerve root transfer and accessory nerve transfer to suprascapular nerve or phrenic nerve transfer to anterior upper trunk was performed, and the second stage procedure of the contralateral C7 nerve root transfer to median nerve and intercostal nerve transfer to axillary nerve was performed. In 4 patients having phrenic nerve and accessory nerve injuries, the first stage procedure of the contralateral C7 nerve root transfer and second stage procedure of the contralateral C7 nerve root transfer to median nerve and musculocutaneous nerve were performed. In 3 patients having hemothorax, pneumothorax, and rib fractures, the first stage procedure of the contralateral C7 nerve root transfer and accessory nerve transfer to suprascapular nerve, and the second stage procedure of the contralateral C7 nerve root transfer to median nerve and musculocutaneous nerve were performed. The British Medical Research Council (MRC) sensory grading (S0-S4) and modified muscle strength grading standard (M0-M5) were used for comprehensive assessment of limb and shoulder abduction, elbow/biceps muscle strength, flexor wrist and finger muscle strength and median nerve sensory recovery. ResultsTwenty-three patients were followed up 3-4.5 years (mean, 3.4 years). At 3 years after operation, the shoulder abduction reached 0-82°(mean, 44°). In 16 patients having no associated injuries, the shoulder abduction was more than 30°in 13 cases, and was more than 60°in 3 cases; in 3 patients having hemothorax, pneumothorax, and rib fractures, the shoulder abduction was more than 30°; and in 4 patients having phrenic nerve and accessory nerve injuries, the shoulder abduction was 0°. The muscle strength of elbow/biceps was M3 or more than M3 in 9 cases, was M1-M2 in 8 cases, and was M0 in 6 cases; the muscle strength of flexor wrist or finger was M3 or more than M3 in 7 cases, was M1-M2 in 11 cases, and was M0 in 5 cases. Median nerve sensory recovery was S3 or more than S3 in 11 cases, was S1-S2 in 7 cases, and was S0 in 5 cases. After 3 years, affected limb had locomotor activity in 11 patients, affected limb had activities driven by the contralateral latissimus dorsi muscle contraction in 12 patients. ConclusionContralateral C7 nerve root and multiple nerves transfer is a good method to treat brachial plexus root avulsion.