Su Jiang

Endoscopy-assisted cubital tunnel release under carbon dioxide insufflation and anterior transposition.

Purpose:The optimal treatment for cubital tunnel syndrome is widely debated. The purpose of this study is to describe the technique of an endoscopic-assisted ulnar nerve decompression using carbon dioxide insufflation in association with subcutaneous anterior transposition and to assess the success or failure of the method of treatment. Methods:In all, 8 male and 4 female patients with an average age of 42 years (range, 25–56) who presented signs, symptoms, and abnormal neurophysiological studies of cubital tunnel syndrome were recruited in the retrospective study. Between August 2008 and June 2009, they were operated on using a 0-degree lens endoscope. Preoperatively, they were classified according to the Dellon scale, and the Bishop rating system was used to evaluate the postoperative outcomes. Results:Preoperatively, 5 patients were rated as mild, another 5 as moderate, and the remaining 2 as severe. The average length of the incision was 15 ± 3 mm, the mean length of the ulnar nerve decompression was 18 ± 2 cm, and the whole duration of surgery (skin to skin) lasted 30 ± 5 minutes. The endoscopic-assisted cubital tunnel release under carbon dioxide insufflation and subcutaneous anterior transposition surgeries in all patients were performed with no difficulty. All the patients had improvement in symptoms of cubital tunnel syndrome and 10 of 12 patients scored excellent according to the modified Bishop Rating System at a minimum of 1 year after surgery. Conclusions:Endoscopy-assisted cubital tunnel release under carbon dioxide insufflation demonstrated similar results compared with conventional open surgeries, besides, it may avoid problems such as long incision, painful scarring, and have additional advantages of providing an extended endoscopic view, which is safe and mini-invasive with favorable results in a 12-month follow-up.

Hand prehension recovery after brachial plexus avulsion injury by performing a full-length phrenic nerve transfer via endoscopic thoracic surgery

OBJECT The functional recovery of hand prehension after complete brachial plexus avulsion injury (BPAI) remains an unsolved problem. The authors conducted a prospective study to elucidate a new method of resolving this injury. METHODS Three patients with BPAI underwent a new procedure during which the full-length phrenic nerve was transferred to the medial root of the median nerve via endoscopic thoracic surgery support. All 3 patients were followed up for a postoperative period of > 3 years. RESULTS The power of the palmaris longus, flexor pollicis longus, and the flexor digitorum muscles of all 4 fingers reached Grade 3-4/5, and no symptoms of respiratory insufficiency occurred. CONCLUSIONS Neurotization of the phrenic nerve to the medial root of the median nerve via endoscopic thoracic surgery is a feasible means of early hand prehension recovery after complete BPAI.

Contralateral Peripheral Neurotization for Hemiplegic Upper Extremity After Central Neurologic Injury

BACKGROUND Central neurological injury (CNI) is a major contributor to physical disability that affects both adults and children all over the world. The main sequelae of chronic stage CNI are spasticity, paresis of specific muscles, and poor selective motor control. Here, we apply the concept of contralateral peripheral neurotization in spasticity releasing and motor function restoration of the affected upper extremity. OBJECTIVE A clinical investigation was performed to verify the clinical efficacy of contralateral C7 neurotization for rescuing the affected upper extremity after CNI. METHODS In the present study, 6 adult hemiplegia patients received the nerve transfer surgery of contralateral C7 to C7 of the affected side. Another 6 patients with matched pathological and demographic status were assigned to the control group that received rehabilitation only. During the 2-year follow-up, muscle strength of bilateral upper extremities was assessed. The Modified Ashworth Scale and Fugl-Meyer Assessment Scale were used for evaluating spasticity and functional use of the affected upper extremity, respectively. RESULTS Both flexor spasticity release and motor functional improvements were observed in the affected upper extremity in all 6 patients who had surgery. The muscle strength of the extensor muscles and the motor control of the affected upper extremity improved significantly. There was no permanent loss of sensorimotor function of the unaffected upper extremity. CONCLUSION This contralateral C7 neurotization approach may open a door to promote functional recovery of upper extremity paralysis after CNI.

Local and Extensive Neuroplasticity in Carpal Tunnel Syndrome: A Resting-State fMRI Study:

Carpal tunnel syndrome (CTS) is a most common peripheral nerve entrapment neuropathy characterized by sensorimotor deficits in median nerve innervated digits. Block-design task-related functional magnetic resonance imaging (fMRI) studies have been used to investigate CTS-related neuroplasticity in the primary somatosensory cortices. However, considering the persistence of digital paresthesia syndrome caused by median nerve entrapment, spontaneous neuronal activity might provide a better understanding of CTS-related neuroplasticity, which remains unexplored. The present study aimed to investigate both local and extensive spontaneous neuronal activities with resting-state fMRI. A total of 28 bilateral CTS patients and 24 normal controls were recruited, and metrics, including amplitude of low-frequency fluctuation (ALFF) and voxel-wise functional connectivity (FC), were used to explore synaptic activity at different spatial scales. Correlations with clinical measures were further investigated by linear regression. Decreased amplitudes of low-frequency fluctuation were observed in the bilateral primary sensory cortex (SI) and secondary sensory cortex (SII) in CTS patients (AlphaSim corrected P < .05). This was found to be negatively related to the sensory thresholds of corresponding median nerve innervated fingers. In the voxel-wise FC analysis, with predefined seed regions of interest in the bilateral SI and primary motor cortex, we observed decreased interhemispheric and increased intrahemispheric FC. Additionally, both interhemispheric and intrahemispheric FC were found to be significantly correlated with the mean ALFF.

Enhancement of Contralesional Motor Control Promotes Locomotor Recovery after Unilateral Brain Lesion.

There have been controversies on the contribution of contralesional hemispheric compensation to functional recovery of the upper extremity after a unilateral brain lesion. Some studies have demonstrated that contralesional hemispheric compensation may be an important recovery mechanism. However, in many cases where the hemispheric lesion is large, this form of compensation is relatively limited, potentially due to insufficient connections from the contralesional hemisphere to the paralyzed side. Here, we used a new procedure to increase the effect of contralesional hemispheric compensation by surgically crossing a peripheral nerve at the neck in rats, which may provide a substantial increase in connections between the contralesional hemisphere and the paralyzed limb. This surgical procedure, named cross-neck C7-C7 nerve transfer, involves cutting the C7 nerve on the healthy side and transferring it to the C7 nerve on the paretic side. Intracortical microstimulation, Micro-PET and histological analysis were employed to explore the cortical changes in contralesional hemisphere and to reveal its correlation with behavioral recovery. These results showed that the contralesional hemispheric compensation was markedly strengthened and significantly related to behavioral improvements. The findings also revealed a feasible and effective way to maximize the potential of one hemisphere in controlling both limbs.

Contralateral Lumbar to Sacral Nerve Rerouting for Hemiplegic Patients After Stroke: A Clinical Pilot Study

BACKGROUND Spasticity and muscle weakness are common severe neurologic sequelae after stroke. Contralateral peripheral neurotization has been applied successfully to promote motor function of the hemiplegic upper extremity in patients with central neurological injury. To our knowledge, we present the first report of contralateral lumbar to sacral nerve transfer for the lower extremities in hemiplegic patients after stroke. CASE DESCRIPTION Two patients were enrolled in the study. The first patient is a 57-year-old man who experienced permanent muscle weakness in his left leg after a right cerebral infarction. The second patient is a 42-year-old man who had spasticity and hemiplegia in both upper and lower limbs on the right side 32 months after a left cerebral hemorrhage. Both patients underwent contralateral lumbar-to-sacral nerve rerouting to improve lower-limb motor function. Twenty months after surgery, both patients experienced significant improvement in ambulatory status. CONCLUSIONS Although long-term follow-up and a randomized controlled trial are required, this study demonstrates the safety and possible benefits of contralateral lumbar-to-sacral nerve transfer for hemiplegic patients after stroke. This novel surgical approach could provide a new means for lower-limb motor functional recovery.

Comparative effects of implanted electrodes with differing contact patterns on peripheral nerve regeneration and functional recovery

Electrical stimulation could enhance nerve regeneration and functional recovery. The objective of this study was to evaluate the regenerative effects of implanted electrodes with different contacts in resected sciatic nerve. Sciatic nerve resection and microsurgical repair models were established and randomly divided into four groups (point contact, 1/4 circle contact; whole-circle contact; no electrodes as control). Electrical stimulation was performed and electrophysiological, morphological and histological exams (of the sciatic nerve and muscle) were conducted at 4 and 10 weeks post-implantation. Point and 1/4 circle contact groups showed significantly higher scores in the sciatic functional index (SFI), increased amplitude of compound muscle action potential (AMP) and motor nerve conduction velocity (MNCV) compared to the control group at both 4 and 10 weeks post-implantation. Point and 1/4 circle contact morphologically promoted sciatic nerve regeneration and reduced muscular atrophy with less mechanical injury to the nerve trunk observed compared with the whole-circle contact group at both 4 and 10 weeks post-implantation. Electrodes with point and 1/4 circle contacts represented an alternatively portable and effective method of electrical stimulation to facilitate injured sciatic nerve regeneration and reduce subsequent muscular atrophy, which might offer a promising approach for treating peripheral nerve injuries.

Contralateral C7 to C7 nerve root transfer in reconstruction for treatment of total brachial plexus palsy: anatomical basis and preliminary clinical results

OBJECTIVEContralateral C7 (CC7) nerve root has been used as a donor nerve for targeted neurotization in the treatment of total brachial plexus palsy (TBPP). The authors aimed to study the contribution of C7 to the innervation of specific upper-limb muscles and to explore the utility of C7 nerve root as a recipient nerve in the management of TBPP.METHODSThis was a 2-part investigation. 1) Anatomical study: the C7 nerve root was dissected and its individual branches were traced to the muscles in 5 embalmed adult cadavers bilaterally. 2) Clinical series: 6 patients with TBPP underwent CC7 nerve transfer to the middle trunk of the injured side. Outcomes were evaluated with the modified Medical Research Council scale and electromyography studies.RESULTSIn the anatomical study there were consistent and predominantly C7-derived nerve fibers in the lateral pectoral, thoracodorsal, and radial nerves. There was a minor contribution from C7 to the long thoracic nerve. The average distance from the C7 nerve root to the lateral pectoral nerve entry point of the pectoralis major was the shortest, at 10.3 ± 1.4 cm. In the clinical series the patients had been followed for a mean time of 30.8 ± 5.3 months postoperatively. At the latest follow-up, 5 of 6 patients regained M3 or higher power for shoulder adduction and elbow extension. Two patients regained M3 wrist extension. All regained some wrist and finger extension, but muscle strength was poor. Compound muscle action potentials were recorded from the pectoralis major at a mean follow-up of 6.7 ± 0.8 months; from the latissimus dorsi at 9.3 ± 1.4 months; from the triceps at 11.5 ± 1.4 months; from the wrist extensors at 17.2 ± 1.5 months; from the flexor carpi radialis at 17.0 ± 1.1 months; and from the digital extensors at 22.8 ± 2.0 months. The average sensory recovery of the index finger was S2. Transient paresthesia in the hand on the donor side, which resolved within 6 months postoperatively, was reported by all patients.CONCLUSIONSThe C7 nerve root contributes consistently to the lateral pectoral nerve, the thoracodorsal nerve, and long head of the triceps branch of the radial nerve. CC7 to C7 nerve transfer is a reconstructive option in the overall management plan for TBPP. It was safe and effective in restoring shoulder adduction and elbow extension in this patient series. However, recoveries of wrist and finger extensions are poor.

Automated, highly reproducible, wide-field, light-based cortical mapping method using a commercial stereo microscope and its applications

We introduce a more flexible optogenetics-based mapping system attached on a stereo microscope, which offers automatic light stimulation to individual regions of interest in the cortex that expresses light-activated channelrhodopsin-2 in vivo. Combining simultaneous recording of electromyography from specific forelimb muscles, we demonstrate that this system offers much better efficiency and precision in mapping distinct domains for controlling limb muscles in the mouse motor cortex. Furthermore, the compact and modular design of the system also yields a simple and flexible implementation to different commercial stereo microscopes, and thus could be widely used among laboratories.