Selective restoration of sensation by peripheral nerve grafts directly implanted into the contralateral C7 dorsal root ganglion: an experimental study in rat brachial plexus

Clinical Features of Herniated Disc at Cervicothoracic Junction Level Treated by Anterior Approach

OBJECTIVE

The anterior approach for C7-T1 disc herniation may be challenging because of obstruction by the manubrium and the narrow operative field. This study aimed to investigate the clinical and neurological outcomes of anterior approach for C7-T1 disc herniation.

METHODS

We retrospectively evaluated 13 patients who underwent the anterior approach for C7-T1 disc herniation by a single surgeon within a period of 11 years (2003-2014). The minimum follow-up duration was 6 months. We describe the clinical presentation, radiographic findings, neurological outcome, and related complications.

RESULTS

Of 372 patients with single-level anterior discectomy and fusion or artificial disc replacement for cervical disc herniation, 13 (3.5%) had C7-T1 disc herniation. The main clinical presentation was unilateral motor weakness in intrinsic hand muscles (11 patients), along with numbness, pain, and tingling sensation that radiate down the arm to the little finger. Most of the patients improved after surgery via the anterior approach. Ten patients underwent successful anterior discectomy and fusion by the standard supramanubrial Smith-Robinson approach, but 2 needed additional manubriotomy and sternotomy. In 1 patient, we performed surgery at a wrong level because the correct level was difficult to identify intraoperatively. Two patients had transient vocal dysfunction, but none had major complications related to injuries of the great vessels such as the thoracic duct or esophagus.

CONCLUSION

For patients who require direct anterior decompression for C7-T1 disc herniation, the anterior approach is relatively feasible. However, care should be taken to overcome physical constraints by the manubrium and slope.

Surgical planning and neurological outcome after anterior approach to remove a disc herniation at the C7-T1 level in 19 patients

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The purpose of this study was to report the neurological presentation, outcome and surgical planning in a series of patients with a symptomatic single-level C7-T1 disc herniation who underwent anterior surgical discectomy and fusion.

SUMMARY OF BACKGROUND DATA

Disc herniations at C7-T1 are uncommon, and there are few large series in the literature describing anterior treatment of such herniations.

METHODS

We performed a retrospective study of patients who underwent surgery for a C7-T1 disc herniation and reviewed the medical records, operative reports, and imaging studies. The surgeons' view line was drawn and its relation to the manubrium and the great vessels was determined on T1 sagittal magnetic resonance imaging. The location of the herniated disc in the spinal canal was determined using a T2 axial magnetic resonance imaging and classified as central, foraminal, and central/foraminal. Loss of muscle strength was evaluated preoperatively and at the last follow-up according to the classification of the Medical Research Council. The disc space was approached anteriorly by a standard cervical supramanubrial Smith-Robinson approach.

RESULTS

We identified 19 patients who had undergone C7-T1 discectomy and fusion. The mean age of the sample was 54.26 ± 8.65 years. There was a higher proportion of male patients (57.9%, 11/19). The clinical presentation was predominantly motor deficit in 15/19 cases (78.9%) in intrinsic hand muscles, and usually improved after surgery. The mean follow-up period was 27.05 ± 15.10 months. All the patients underwent an anterior cervical supramanubrial approach with microdiscectomy and fusion. Anterior cervical plate fixation was used in 9/19 cases (47.3%). In the rest of the cases, a stand-alone intervertebral device was placed.

CONCLUSION

An anterior cervical supramanubrial approach was easily accomplished in all patients. Motor deficit was the most common surgical indication.

LEVEL OF EVIDENCE

4.

Brachial plexus injury in adults: Diagnosis and surgical treatment strategies

Adult post traumatic Brachial plexus injury is unfortunately a rather common injury in young adults. In India the most common scenario is of a young man injured in a motorcycle accident. Exact incidence figures are not available but of the injuries presenting to us about 90% invole the above combination This article reviews peer-reviewed publications including clinical papers, review articles and Meta analysis of the subject. In addition, the authors' experience of several hundred cases over the last 15 years has been added and has influenced the ultimate text. Results have been discussed and analysed to get an idea of factors influencing final recovery. It appears that time from injury and number of roots involved are most crucial.

Quantitative evaluation of movement and strength of the upper limb after transection of the C-7 nerve: is it possible in an animal model?

Object

Contralateral C-7 nerve transfer has been used clinically for more than 20 years. The increased interest in studies of transfer effectiveness at different target muscles, posttransfer cocontraction, and brain plasticity has prompted the need for an animal model. In addition to the conventional electrophysiological, histomorphometric, and biomechanical evaluation modalities, quantitative functional and behavioral evaluation will be crucial in applying this kind of model. The aim of this study was to establish a C-7 transection animal model and quantify the changes in upper-limb joint movement and muscle power.

Methods

A C-7 nerve transection model was created in Sprague-Dawley rats, the brachial plexus of which resembles the human brachial plexus. The impact of C-7 transection on donor limb function—namely, strength, movement, and coordination—was evaluated in 6 rats. Muscle strength (power reported in g) was measured as a grasping task. The active range of motion (ROM; angle reported in °) of the elbow, wrist, and metacarpophalangeal joints was quantified by computerized video motion analysis. Antiresistance coordinated movement (speed reported in seconds) was assessed by the vertical rope-climbing test. These tests were carried out before surgery and at 2, 4, 6, 8, 10, 14, 21, and 28 days after C-7 transection. Repeated-measures 1-way analysis of variance was applied for statistical analysis. When the overall probability value was < 0.05, the Dunnett multiple-comparison posttest was used to compare postoperative values with preoperative baseline values.

Results

Immediately after C-7 transection, the mean ± SD grip strength declined from 378.50 ± 20.55 g to 297.77 ± 15.04 g. Active elbow extension was impaired, as shown by a significant decrease of the elbow extension angle. The speed of vertical rope climbing was also reduced. Elbow flexion, wrist flexion and extension, and metacarpophalangeal joint flexion and extension were not impaired. Fast recovery of motor function was observed thereafter. Grip strength, range of active elbow extension, and speed of rope climbing returned to baseline values at postoperative Days 4, 8, and 8, respectively.

Conclusions

The ROM and muscle strength of the upper limb in rats can be measured quantitatively in studies that simulate clinical situations. Application of these functional evaluation modalities in a C-7 nerve transection rat model confirmed that transection of C-7 causes only temporary functional dysfunction to the donor limb. The results obtained in this animal model mimic those seen in humans who undergo contralateral C-7 nerve harvesting.

Myelopathy caused by soft cervical disc herniation : surgical results and prognostic factors

OBJECTIVE

The purpose of this study was to investigate the surgical results and prognostic factors for patients with soft cervical disc herniation with myelopathy.

METHODS

During the last 7 years, 26 patients with cervical discogenic myelopathy were undertaken anterior discectomy and fusion. Clinical and radiographic features were reviewed to evaluate the surgical results and prognostic factors. The clinical outcome was judged using two grading systems (Herkowitz's scale and Nurick's grade).

RESULTS

Male were predominant (4:1), and C5-6 was the most frequently involved level. Gait disturbance, variable degree of spasticity, discomfort in chest and abdomen, hand numbness were the most obvious signs. Magnetic resonance(MR) images showed that central disc herniation was revealed in 16 cases, and accompanying cord signal changes in 4. Postoperatively, 23 patients showed favorable results (excellent, good and fair) according to Herkowitz's scale.

CONCLUSION

Anterior cervical discectomy and fusion effectively reduced myelopathic symptoms due to soft cervical disc herniation. The authors assured that the shorter duration of clinical attention, the lesser the degree of myelopathy and better outcome in discogenic myelopathy.

Concepts of nerve regeneration and repair applied to brachial plexus reconstruction

Brachial plexus injury is a serious condition that usually affects young adults. Progress in brachial plexus repair is intimately related to peripheral nerve surgery, and depends on clinical and experimental studies. We review the rat brachial plexus as an experimental model, together with its behavioral evaluation. Techniques to repair nerves, such as neurolysis, nerve coaptation, nerve grafting, nerve transfer, fascicular transfer, direct muscle neurotization, and end-to-side neurorraphy, are discussed in light of the authors' experimental studies. Intradural repair of the brachial plexus by graft implants into the spinal cord and motor rootlet transfer offer new possibilities in brachial plexus reconstruction. The clinical experience of intradural repair is presented. Surgical planning in root rupture or avulsion is proposed. In total avulsion, the authors are in favor of the reconstruction of thoraco-brachial and abdomino-antebrachial grasping, and on the transfer of the brachialis muscle to the wrist extensors if it is reinnervated. Surgical treatment of painful conditions and new drugs are also discussed.

Cost-utility analysis of routine neurosurgical spinal surgery

OBJECT

Cost-utility analysis is currently the preferred method with which to compare the cost-effectiveness of various interventions. The authors conducted a study to establish the cost-utility results of routine neurosurgery-based spinal interventions by examining patient-derived values.

METHODS

Two hundred seventy patients undergoing surgery for cervical or lumbar radicular pain filled in the 15-dimensional health-related quality of life (HRQOL) questionnaire before and 3 months after surgery. Quality-adjusted life years (QALYs) were calculated using the utility data and the expected remaining life years of the patients. The mean HRQOL score (scale, 0-1) increased after cervical surgery (169 patients, mean age 52 years, 40% women) from 0.81 +/- 0.11 preoperatively, to 0.85 +/- 0.11 at 3 months, and after lumbar surgery (101 patients, mean age 54 years, 59% women) from 0.79 +/- 0.10 preoperatively, to 0.85 +/- 0.12 at 3 months (p < 0.001). Of the 15 dimensions of health, improvement in the following was documented in both groups: sleeping, usual activities, discomfort and symptoms, depression, distress, vitality, and sexual activity (p < 0.05). The cost per QALY gained was Euro 2774 and 1738 for cervical and lumbar operations, respectively. In cases in which surgery was delayed the cost per QALY was doubled.

CONCLUSIONS

Spinal surgery led to a statistically significant and clinically important improvement in HRQOL. The cost per QALY gained was reasonable, less than half of that observed, for example, for hip replacement surgery or angioplasty treatment of coronary artery disease; however, a prolonged delay in surgical intervention led to an approximate doubling of the cost per QALY gained by the treatment.

Posterior foraminotomy or anterior discectomy with polymethyl methacrylate interbody stabilization for cervical soft disc disease: results in 292 patients with monoradiculopathy

STUDY DESIGN

Retrospective study of patients who underwent either ventral microdiscectomy and polymethyl methacrylate (PMMA) interbody stabilization or posterior foraminotomy for the treatment of cervical monoradiculopathy caused by soft disc disease.

OBJECTIVES

To evaluate the long-term outcome after 2 different surgical procedures in the treatment of cervical radiculopathy, compare them with each other and with previous data from other surgical techniques, and outline the indications, advantages, and disadvantages of each procedure.

SUMMARY OF BACKGROUND DATA

Cervical disc disease can lead to morphologic different disc lesions, which again may differ in clinical presentation, operative treatment, and outcome. This study provides a clinical long-term follow-up of ventral and dorsal approaches.

METHODS

Follow-up evaluation (mean 72.1 +/- 25.9 months) after surgery of monoradicular symptoms was performed in 292 patients. Patients with hard disc disease, myelopathy, neoplasms, or traumatic or recurrent cervical disc disease were excluded. A total of 124 patients (42.5%) underwent ventral microdiscectomy and PMMA stabilization (group A), and in 168 patients (57.5%), a posterior foraminotomy was performed (group B). The outcome was determined according to Odom criteria based on a questionnaire or a telephone interview and was related to the following variables: morphologic findings, neurologic findings, duration of symptoms, operation technique applied, age, sex, and cervical level involved.

RESULTS

The success rate (Odom I + II) without consideration of morphologic findings was higher after anterior microdiscectomy with PMMA stabilization (93.6%) than after posterior foraminotomy (85.1%) (P < 0.05). The success rate was higher in cases with pure soft discs in both groups (A: 96.6%; B: 85.8%) than in cases with a mixture of soft and hard discs (A: 90.6%; B: 80%), without gaining statistical significance. Complications related to surgery occurred in 6.5% (group A) and 1.8% (group B) of patients (P < 0.05).

CONCLUSION

The findings show that apparently a higher success rate results after anterior microdiscectomy with PMMA interbody stabilization for treatment of degenerative cervical monoradiculopathy than after posterior foraminotomy. Considering the type of morphology of the pathology that causes the radiculopathy, pure soft discs have a better outcome than mixtures of soft and hard discs, independent of the chosen approach. Although statistically significant differences in clinical data were found in both groups, both approaches seem to have equivalent value in individual indications.

Evaluation of the kinesthetic sense and function of the hand in early period in operated cervical disc hernia

A prospective study made into cervical disc hernias. To determine the kinesthetic sense and hand functions, which are important for the patients with cervical disc hernia to return to work life and daily activities that need skill. Neurosurgical department. Data Symptoms in cervical disc hernias and hand functions are affected depending on long-term pain. The evaluation of the hand is essential in assessing the patients' overall recovery and ability to return to daily activities and work life. Thirty-four patients with cervical disc hernia, who were operated on, were included in the study. Eight different test positions in the assessment of the hand's kinesthetic sense and hand function sort (HFS) in the evaluation of the hand function were applied. The disability levels of the patients were determined with The Neck Pain and Disability Scale, on the preoperative and postoperative discharge day and in the postoperative second month. Patients were divided into groups according to the side involved. In the evaluation of the kinesthetic test of the hand, only in the postoperative second month was a significant difference observed between the 1, 2, 3, and 4 test positions of the right side of the groups. On the other hand, no significant difference was found between the groups in the assessment of the hand function. In the measurement of hand functions and disability levels, strong and important correlations were determined. An early assessment of the hand's kinesthetic sense and function is instrumental in the patients' evaluation of recovery and resumption of work.

Long interpositional nerve graft consistently induces incomplete motor and sensory recovery in the rat

Motor and sensory regeneration was studied in a 40 mm long graft interposed between the sectioned stumps of the rat median nerve. Animals were behaviorally assessed from 1 to 720 days after surgery by the grasping and modified Randall-Sellito tests. Rats recovered grasping function 43.7 (S.D. +/- 2.6) days after surgery. Grasping strength attained 50 and 65% of the normal control group, 280 and 360 days after surgery, respectively. From 90 to 360 days after surgery, sensory nociceptive recovery was only 30% of the normal control group. The results indicate that motor and sensory neurons were capable of regenerating additional axonal length, but functional return was clearly better in the motor system. This model of deficient reinnervation might prove to be of interest in testing of new strategies for the enhancement of nerve recovery.

Three-Year Retrospective Study of Complications Arising during Interventional Procedures

SUMMARY

This retrospective study aimed to assess the percentage of complications arising in our daily practice of interventional procedures, comparing our findings with those of leading international reference centers and accepted guidelines for endovascular treatment. During the threeyear period considered (2000-2002), we performed 246 interventional procedures, divided into seven different pathological conditions: aneurysms, brain AVMs dural and carotid cavernous fistulae, spine-spinal cord tumours, headneck tumours, carotid stenosis and thrombolysis. Aneurysmal disease accounted for 45% of all endovascular procedures. In conclusion, four periprocedural complications arose in the course of 246 procedures resulting in one death and three cases of permanent neurological deficit (2%).

Bioabsorbable polymeric material coils for embolization of intracranial aneurysms: a preliminary experimental study

OBJECT

A new embolic agent, bioabsorbable polymeric material (BPM), was incorporated into Guglielmi detachable coils (GDCs) to improve long-term anatomical results in the endovascular treatment of intracranial aneurysms. The authors investigated whether BPM-mounted GDCs (BPM/GDCs) accelerated the histopathological transformation of unorganized blood clot into fibrous connective tissue in experimental aneurysms created in swine.

METHODS

Twenty-four experimental aneurysms were created in 12 swine. In each animal, one aneurysm was embolized using BPM/GDCs and the other aneurysm was embolized using standard GDCs. Comparative angiographic and histopathological data were analyzed at 2 weeks and 3 months postembolization. At 14 days postembolization, angiograms revealed evidence of neck neointima in six of eight aneurysms treated with BPM/GDCs compared with zero of eight aneurysms treated with standard GDCs (p < 0.05). At 3 months postembolization, angiograms demonstrated that four of four aneurysms treated with BPM/GDC were smaller and had neck neointima compared with zero of four aneurysms treated with standard GDCs (p = 0.05). At 14 days, histological analysis of aneurysm healing favored BPM/GDC treatment (all p < 0.05): the grade of cellular reaction around the coils was 3 +/- 0.9 (mean +/- standard deviation) for aneurysms treated using BPM/GDCs compared with 1.6 +/- 0.7 for aneurysms treated using GDCs alone; the percentage of unorganized thrombus was 16 +/- 12% compared with 37 +/- 15%, and the neck neointima thickness was 0.65 +/- 0.26 mm compared with 0.24 +/- 0.21 mm, respectively. At 3 months postembolization, only neck neointima thickness was significantly different (p < 0.05): 0.73 +/- 0.37 mm in aneurysms filled with BPM/GDCs compared with 0.16 +/- 0.14 mm in aneurysms filled with standard GDCs.

CONCLUSIONS

In experimental aneurysms in swine, BPM/GDCs accelerated aneurysm fibrosis and intensified neck neointima formation without causing parent artery stenosis or thrombosis. The use of BPM/GDCs may improve long-term anatomical outcomes by decreasing aneurysm recanalization due to stronger in situ anchoring of coils by organized fibrous tissue. The retraction of this scar tissue may also decrease the size of aneurysms and clinical manifestations of mass effect observed in large or giant aneurysms.

Cross-chest radial nerve transfer in brachial plexus injuries. Experimental and anatomical basis

Brachial plexus avulsion injuries are devastating injuries to the upper limb, and nerve transfer remains the only option in reconstruction. Despite the encouraging results concerning recovery of shoulder and elbow function, no option is available for treatment of the paralytic hand. In rats, we sectioned the radial nerve in the elbow region and transferred it across the chest to reinnervate the lesioned contralateral medial cord of the brachial plexus. Rats were then evaluated for motor and sensory recovery, electrophysiologically, behaviorally and morphologically. Forepaw functional recovery was estimated to be 90%. In cadavers, the radial nerve and profunda brachii artery were dissected. It was observed that the radial nerve vascularized by the profunda brachii artery was able to reach the contralateral brachial plexus distal to the shoulder region without nerve grafts. After sectioning the radial nerve, sensory loss is minimal and motor palsy can be easily restored by tendon transfers. The results of tendon transfer for radial nerve palsy are better than for any other nerve. Cross-chest radial nerve transfer might be of clinical interest in the reconstruction of hand function in entire injury to the brachial plexus.

Brachial plexus dorsal rhizotomy in the treatment of upper-limb spasticity

OBJECT

This study was conducted to evaluate the effects of dorsal rhizotomy on upper-limb spasticity, functional improvement, coordination, and hand sensibility.

METHODS

Fifteen spastic upper limbs in 13 patients were selected and prospectively studied. Brachial plexus dorsal rhizotomy was performed in which two, three, or four dorsal roots were completely sectioned. Patients were followed up for at least 12 months after surgery; the mean follow-up period was 15.6 months and the maximum period was 30 months. A remarkable relief of spasticity was observed in all cases. Recurrence was observed in only one patient and was caused by insufficient dorsal root section. Functional improvement was observed in all cases, and functional improvement in the hand was found to be related to the presence of active finger extension in the preoperative period. Even when extended dorsal root section was performed, no hand anesthesia, either total or partial, was observed. No patient lost movement ability in the postoperative period, and no ataxic limbs were observed.

CONCLUSIONS

Brachial plexus dorsal rhizotomy is very effective as a treatment for upper-limb spasticity and results in functional improvement without loss of sensation in the hand.

A surgical approach for concomitant spinal cord and brachial plexus surgery: an anatomical study

Spinal cord surgery is not the current treatment for brachial plexus avulsion injuries. However, several experimental and a few clinical cases have been reported with promising results. This surgical strategy in the near future, might prove to be useful. Different simultaneous anatomical approaches to the brachial plexus and spinal cord were studied in attempt to discover the best route to be used in the surgical reconstruction of avulsion lesions of the brachial plexus by spinal cord surgery. Eleven fresh subjects were used to compare: a) simultaneous dorsal approaches to the brachial plexus and spinal cord, b) the dorsal approach to the spinal cord and the anterior approach to the brachial plexus, c) a dorsal approach to the spinal cord combined with a dorsal approach through the triceps muscle to the terminal branches of the brachial plexus and d) a purely anterior approach to the spinal cord and brachial plexus. During the study, special attention was paid to the length of the grafts needed for repair, the possibility of entire exposure of the brachial plexus and the possibility of performing concomitant nerve transfers. As a result of the anatomical findings, we would suggest a dorsal approach to the spinal cord, suprascapular nerve and sometimes to the axillary nerve, combined with an anterior exposure to the brachial plexus in order to have the whole plexus explored and routine simultaneous nerve transfers performed. In selected cases, with limited root injuries, the dorsal approach to the brachial plexus and spinal cord and the anterior approach to the brachial plexus and spinal cord might be of interest.