Clinical evaluation of C7 spinal nerve transection: 21 patients with at least 2 years' follow-up

Surgical reconstructions for adult brachial plexus injuries. Part II: Treatments for total arm type

Brachial plexus injuries (BPI) contribute not only to physical dysfunction but also to socioeconomic aspects and psychological disability. Patients with total arm-type BPI will lose not only the shoulder and elbow function but also the hand function, making reconstruction particularly challenging. Reconstructive procedures commonly include nerve repair, grafting, neurotization (nerve transfer), tendon transfer and free functional muscle transfer (FFMT). Although it is difficult to achieve prehensile hand function, most of patients with total arm-type BPI can be treated with satisfied outcomes. In addition to surgical techniques, comprehensive rehabilitation is another important factor for successful outcomes, and efficient communication can help to boost patient morale and eliminate uncertainty.

Prespinal Versus Conventional Hemicontralateral C7 Nerve Transfer in the Treatment of Total Brachial Plexus Roots Avulsion Injuries: A Retrospective Study With a Minimum Follow-Up Period of 4 Years

PURPOSE

Contralateral C7 (CC7)-to-median nerve transfer has been commonly used to restore hand function in brachial plexus injury. To shorten the nerve graft, the prespinal route was described and achieved direct coaptation when combined with humeral shortening osteotomy. The limb was positioned at 0° shoulder abduction and neutral head position. Given our concern about donor-site morbidity when harvesting the whole CC7 nerve and tension across the neurorrhaphy site after mobilization, we aimed to describe our modified prespinal route and compare its outcomes and complications with the conventional hemi-CC7 transfer.

METHODS

From 2004 to 2014, 39 patients with preganglionic total brachial plexus root avulsion injuries, with a minimum of 4 years of follow-up, were included. Overall, 20 and 19 patients underwent the conventional hemi-CC7-to-median nerve and hemi-CC7-to-lower trunk (LT) transfer through the modified prespinal route, respectively. The modified prespinal route was combined with bilateral clavicle shortening osteotomy to achieve direct coaptation to the LT at 45° shoulder abduction.

RESULTS

The modified prespinal route showed the median period to achieve ≥M3 hand grip assessed in clinical follow-up was shorter (26.5 months vs 45.5 months), and a higher proportion of patients achieved ≥M3 hand grip recovery (63% vs 30%). One patient experienced symptomatic phrenic nerve injury; however, the hemidiaphragm fully recovered after 6 months. The long-term donor-site complication rate was 2.6%, including one sensory abnormality, and no permanent donor-site weakness after hemi-CC7 harvesting was observed.

CONCLUSIONS

The modified prespinal route combined with clavicle osteotomy allowed direct coaptation to the LT and did not require head immobilization. It may allow a higher proportion of patients to achieve ≥M3 hand grip more quickly than conventional hemi-CC7 transfer.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Long-Term Outcome of 118 Acute Total Brachial Plexus Injury Patients Using Free Vascularized Ulnar Nerve Graft to Innervate the Median Nerve

BACKGROUND

 The restoration of finger movement in total brachial plexus injuries (BPIs) is an ultimate challenge. Pedicled vascularized ulnar nerve graft (VUNG) connecting a proximal root to distal target nerves has shown unpredictable outcomes. We modified this technique by harvesting VUNG as a free flap to reinnervate median nerve (MN). We analyzed the long-term outcomes of these methods.

METHODS

 From years 1998 to 2015, 118 acute total brachial plexus patients received free VUNG to innervate the MN. Patients were followed up at least 5 years after the initial surgery. Donor nerves included the ipsilateral C5 root (25 patients) or contralateral C7 root (CC7 = 93 patients). Recovery of finger and elbow flexion was evaluated with the modified Medical Research Council system. Michigan Hand Score and Quick-DASH were used to represent the patient-reported outcomes.

RESULTS

 For finger flexion, ipsilateral C5 transfer to MN alone yielded similar outcomes to MN + MCN (musculocutaneous nerve), while CC7 had significantly better finger flexion when coapted to MN alone than to MN + MCN. Approximately 75% patients were able to achieve finger flexion with nerve transfer alone. For elbow flexion, best outcome was seen in the ipsilateral C5 to MCN and MN.

CONCLUSION

 In acute total BPI, the priority is to identify the ipsilateral C5 root to innervate MN, with concomitant innervation of MCN to establish the best outcomes for finger and elbow flexion. CC7 is more reliable when used to innervate one target (MN).

LEVEL OF EVIDENCE

 III.

Contralateral C7 nerve transfer in the treatment of upper-extremity paralysis: a review of anatomical basis, surgical approaches, and neurobiological mechanisms

The previous three decades have witnessed a prosperity of contralateral C7 nerve (CC7) transfer in the treatment of upper-extremity paralysis induced by both brachial plexus avulsion injury and central hemiplegia. From the initial subcutaneous route to the pre-spinal route and the newly-established post-spinal route, this surgical operation underwent a series of innovations and refinements, with the aim of shortening the regeneration distance and even achieving direct neurorrhaphy. Apart from surgical efforts for better peripheral nerve regeneration, brain involvement in functional improvements after CC7 transfer also stimulated scientific interest. This review summarizes recent advances of CC7 transfer in the treatment of upper-extremity paralysis of both peripheral and central causes, which covers the neuroanatomical basis, the evolution of surgical approach, and central mechanisms. In addition, motor cortex stimulation is discussed as a viable rehabilitation treatment in boosting functional recovery after CC7 transfer. This knowledge will be beneficial towards improving clinical effects of CC7 transfer.

Clinical Anatomy of Human Donor C7 Nerve Roots for Surgical Transfer in Patients with Spastic Arm Paralysis

BACKGROUND

Contralateral C7 (CC7) nerve transfer has successfully restored hand function in patients with spastic hemiplegia from chronic central nervous system injuries. However, little is known about the morphology and anatomy of the donor C7 nerve root in patients undergoing this procedure. This study quantified intraoperative measurements of donor C7 nerve roots during CC7 transfer surgery for spastic hemiplegia in patients treated at a high-volume center to describe observed anatomical variations for successful direct anastomosis.

METHODS

A database of images from 21 patients (2 females, 19 males) undergoing CC7 surgery was searched for photographic data that contained a standard ruler measuring donor C7 nerve root length after surgical sectioning and before transfer. Two independent observers analyzed these images and recorded C7 nerve root diameter, length, and branch lengths.

RESULTS

Mean (SD) values of donor C7 nerve measurements were length, 53.5 (8.0) mm; diameter, 5.1 (0.9) mm; branch length following surgical sectioning, 18.3 (6.3) mm. Right-sided donor C7 nerve roots yielded significantly longer branches compared with left-sided donor C7 nerve roots (P = 0.01). Other patient factors such as age, sex, or laterality of brain injury did not influence intraoperative anatomy.

CONCLUSIONS

We report detailed intraoperative measurements of the donor C7 root during CC7 nerve transfer for spastic hemiplegia. These findings describe existing variation in surgical C7 nerve root anatomy in patients undergoing this procedure and may serve as a general reference for the expected donor C7 length in successful direct anastomosis.

Direct Repair of the Lower Trunk to Residual Nerve Roots for Restoration of Finger Flexion After Total Brachial Plexus Injury

PURPOSE

Residual nerve root stumps have been used to neurotize the median nerve in an attempt to restore finger flexion function in patients suffering from total brachial plexus injury. However, the results have been unsatisfactory mainly because of the need to use a long nerve graft. The authors have tried to improve the quality of restored finger flexion by direct approximation of available (ruptured) ipsilateral root stumps to the lower trunk (LT). We sought to validate these results using objective outcome measures.

METHODS

This is a study of 27 cases of total posttraumatic brachial plexus palsies. In each case, the neck was explored and ruptured root stumps identified. The LT was mobilized by separating it from the posterior division and the medial cutaneous nerve of the forearm distally. The mobilized LT was then approximated directly to an ipsilateral root stump. The arm was immobilized against the trunk for 2 months. The patients were observed for return of function in the paralyzed upper limb. The presence and strength of finger flexion was measured using the British Medical Council grading.

RESULTS

The follow-up period was 36 to 74 months (average, 56.9 ± 13.7 months). Recovery of active finger flexion was M4 in 10 patients, M3 in 8 patients, and M2 to M0 in 9 patients. Meaningful recovery (M3 or greater) of finger flexion was achieved in 18 of 27 patients.

CONCLUSIONS

The results of active finger flexion can be improved by direct approximation of the LT to an ipsilateral root stump.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Comparison between direct repair and human acellular nerve allografting during contralateral C7 transfer to the upper trunk for restoration of shoulder abduction and elbow flexion

Direct coaptation of contralateral C7 to the upper trunk could avoid the interposition of nerve grafts. We have successfully shortened the gap and graft lengths, and even achieved direct coaptation. However, direct repair can only be performed in some selected cases, and partial procedures still require autografts, which are the gold standard for repairing neurologic defects. As symptoms often occur after autografting, human acellular nerve allografts have been used to avoid concomitant symptoms. This study investigated the quality of shoulder abduction and elbow flexion following direct repair and acellular allografting to evaluate issues requiring attention for brachial plexus injury repair. Fifty-one brachial plexus injury patients in the surgical database were eligible for this retrospective study. Patients were divided into two groups according to different surgical methods. Direct repair was performed in 27 patients, while acellular nerve allografts were used to bridge the gap between the contralateral C7 nerve root and upper trunk in 24 patients. The length of the harvested contralateral C7 nerve root was measured intraoperatively. Deltoid and biceps muscle strength, and degrees of shoulder abduction and elbow flexion were examined according to the British Medical Research Council scoring system; meaningful recovery was defined as M3–M5. Lengths of anterior and posterior divisions of the contralateral C7 in the direct repair group were 7.64 ± 0.69 mm and 7.55 ± 0.69 mm, respectively, and in the acellular nerve allografts group were 6.46 ± 0.58 mm and 6.43 ± 0.59 mm, respectively. After a minimum of 4-year follow-up, meaningful recoveries of deltoid and biceps muscles in the direct repair group were 88.89% and 85.19%, respectively, while they were 70.83% and 66.67% in the acellular nerve allografts group. Time to C5/C6 reinnervation was shorter in the direct repair group compared with the acellular nerve allografts group. Direct repair facilitated the restoration of shoulder abduction and elbow flexion. Thus, if direct coaptation is not possible, use of acellular nerve allografts is a suitable option. This study was approved by the Medical Ethical Committee of the First Affiliated Hospital of Sun Yat-sen University, China (Application ID: [2017] 290) on November 14, 2017.

The Future of Upper Extremity Spasticity Management

Surgical management of upper limb spasticity has traditionally tackled the downstream effects at the muscle, tendon, and joint levels. Because this approach does not address the underlying pathologic condition within the nerve, surgical outcomes have been marked by unsatisfactory relapse over time. Future management may focus on reestablishing a normal neuronal impulse pathway to the dysfunctional musculotendinous unit. By severing the faulty γ-neuronal circuit at the C7 level, spasticity may be reduced. Transfer of the contralateral C7 nerve root to the injured C7 nerve root may open the potential for simultaneously restoring extension and improving reach and grasp functions.

Retropharyngeal Contralateral C7 Nerve Transfer to the Lower Trunk for Brachial Plexus Birth Injury: Technique and Results

PURPOSE

Brachial plexus birth injuries with multiple nerve root avulsions present a particularly difficult reconstructive challenge because of the limited availability of donor nerves. The contralateral C7 has been described for brachial plexus reconstruction in adults but has not been well-studied in the pediatric population. We present our technique and results for retropharyngeal contralateral C7 nerve transfer to the lower trunk for brachial plexus birth injury.

METHODS

We performed a retrospective review. Any child aged less than 2 years was included. Charts were analyzed for patient demographic data, operative variables, functional outcomes, complications, and length of follow-up.

RESULTS

We had a total of 5 patients. Average nerve graft length was 3 cm. All patients had return of hand sensation to the ulnar nerve distribution as evidenced by a pinch test, unprompted use of the recipient limb without mirror movement, and an Active Movement Scale (AMS) of at least 2/7 for finger and thumb flexion; one patient had an AMS of 7/7 for finger and thumb flexion. Only one patient had return of ulnar intrinsic hand function with an AMS of 3/7. Two patients had temporary triceps weakness in the donor limb and one had clinically insignificant temporary phrenic nerve paresis. No complications were related to the retropharyngeal nerve dissection in any patient. Average follow-up was 3.3 years.

CONCLUSIONS

The retropharyngeal contralateral C7 nerve transfer is a safe way to supply extra axons to the severely injured arm in brachial plexus birth injuries with no permanent donor limb deficits. Early functional recovery in these patients, with regard to hand function and sensation, is promising.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic V.

Is it necessary to use the entire root as a donor when transferring contralateral C7 nerve to repair median nerve?

If a partial contralateral C₇ nerve is transferred to a recipient injured nerve, results are not satisfactory. However, if an entire contralateral C₇ nerve is used to repair two nerves, both recipient nerves show good recovery. These findings seem contradictory, as the above two methods use the same donor nerve, only the cutting method of the contralateral C₇ nerve is different. To verify whether this can actually result in different repair effects, we divided rats with right total brachial plexus injury into three groups. In the entire root group, the entire contralateral C₇ root was transected and transferred to the median nerve of the affected limb. In the posterior division group, only the posterior division of the contralateral C₇ root was transected and transferred to the median nerve. In the entire root + posterior division group, the entire contralateral C₇ root was transected but only the posterior division was transferred to the median nerve. After neurectomy, the median nerve was repaired on the affected side in the three groups. At 8, 12, and 16 weeks postoperatively, electrophysiological examination showed that maximum amplitude, latency, muscle tetanic contraction force, and muscle fiber cross-sectional area of the flexor digitorum superficialis muscle were significantly better in the entire root and entire root + posterior division groups than in the posterior division group. No significant difference was found between the entire root and entire root + posterior division groups. Counts of myelinated axons in the median nerve were greater in the entire root group than in the entire root + posterior division group, which were greater than the posterior division group. We conclude that for the same recipient nerve, harvesting of the entire contralateral C₇ root achieved significantly better recovery than partial harvesting, even if only part of the entire root was used for transfer. This result indicates that the entire root should be used as a donor when transferring contralateral C₇ nerve.

Evaluation of nerve transfer options for treating total brachial plexus avulsion injury: A retrospective study of 73 participants

Despite recent great progress in diagnosis and microsurgical repair, the prognosis in total brachial plexus-avulsion injury remains unfavorable. Insufficient number of donors and unreasonable use of donor nerves might be key factors. To identify an optimal treatment strategy for this condition, we conducted a retrospective review. Seventy-three patients with total brachial plexus avulsion injury were followed up for an average of 7.3 years. Our analysis demonstrated no significant difference in elbow-flexion recovery between phrenic nerve-transfer (25 cases), phrenic nerve-graft (19 cases), intercostal nerve (17 cases), or contralateral C₇-transfer (12 cases) groups. Restoration of shoulder function was attempted through anterior accessory nerve (27 cases), posterior accessory nerve (10 cases), intercostal nerve (5 cases), or accessory + intercostal nerve transfer (31 cases). Accessory nerve + intercostal nerve transfer was the most effective method. A significantly greater amount of elbow extension was observed in patients with intercostal nerve transfer (25 cases) than in those with contralateral C₇ transfer (10 cases). Recovery of median nerve function was noticeably better for those who received entire contralateral C₇ transfer (33 cases) than for those who received partial contralateral C₇ transfer (40 cases). Wrist and finger extension were reconstructed by intercostal nerve transfer (31 cases). Overall, the recommended surgical treatment for total brachial plexus-avulsion injury is phrenic nerve transfer for elbow flexion, accessory nerve + intercostal nerve transfer for shoulder function, intercostal nerves transfer for elbow extension, entire contralateral C₇ transfer for median nerve function, and intercostal nerve transfer for finger extension. The trial was registered at ClinicalTrials.gov (identifier: NCT03166033).

Outcome of Finger Extension After Nerve Transfer to Repair C7-T1 Brachial Plexus Palsy in Rats: Comparative Study of the Supinator Motor Branch Transfer to the Posterior Interosseous Nerve and the Contralateral C7 Transfer to the Lower Trunk

BACKGROUND

Functional recovery following supinator motor branch transfer requires further investigation.

OBJECTIVE

To compare the outcome of finger extension after supinator motor branch transfer or contralateral C7 (cC7) transfer in C7-T1 brachial plexus palsies in rats.

METHODS

In this study, 120 adult rats underwent C7-T1 nerve root avulsion and received different nerve transfer repairs: group A, cC7 nerve transfer to the lower trunk; group B, supinator motor branch nerve transfer to the posterior interosseous nerve (PIN); and group C, no repair. The ethology of the rats, latency and amplitude of the compound muscle action potential from the PIN, muscle mass and muscle fiber cross-sectional area of the extensor digitorum communis and extensor carpi ulnaris, and number of myelinated nerve fibers in the PIN were examined postoperatively.

RESULTS

There was no finger extension in group C. We observed finger extension in groups A and B 50.2 ± 5.66 and 13.1 ± 2.08 days postoperatively, respectively. Finger extension restoration in group B was greater than that in group A at 4, 8, and 12 weeks postoperatively ( P < .05). Sixteen weeks after surgery, the recovery rate of the myelinated nerve fibers in group A was marginally higher than that in group B, but the difference was not significant. Of the other measured values, group B showed a greater and significant improvement compared to group A ( P < .05).

CONCLUSION

Supinator motor branch transfer allows for faster recovery and is a more effective procedure for restoring finger extension in C7-T1 brachial plexus palsies.

Direct Coaptation of the Phrenic Nerve With the Posterior Division of the Lower Trunk to Restore Finger and Elbow Extension Function in Patients With Total Brachial Plexus Injuries

BACKGROUND

To overcome the mismatch in nerve sizes in phrenic nerve transfer to the radial nerve for elbow and finger extension reanimation for patients with total brachial plexus injuries (TBPI), a selective neurotization procedure was designed.

OBJECTIVE

To investigate the long-term results of phrenic nerve transfer to the posterior division of the lower trunk with direct coaptation in restoring elbow and finger extension after TBPI.

METHODS

Phrenic nerve was transferred to and directly coapted with the posterior division of the lower trunk in 27 patients with TBPI. Seven patients were <18 years old (adolescent group), and the remaining 20 patients ≥18 years (adult group).

RESULTS

Postoperative mean follow-up period was 54 ± 9 months (range, 48-85 months). The motor function attained M3 or greater in 81.5% of patients for elbow extension and in 48% of patients for finger extension. The percentage of patients who regained M3 or greater muscle power of finger extension in the adolescent group and the adult group was 71.4%, and 40%, respectively. Meanwhile, 85.7% in the adolescent group and 80% in the adult group achieved M3 or greater muscle power of elbow extension. There were no significant differences between the 2 groups. The elbow extension and finger extension were synchronous contractions and did not become independent of respiratory effort.

CONCLUSION

This procedure simultaneously and effectively restores the function of elbow and finger extension in patients after TBPI. However, the patients could not do elbow and finger extension separately.

A Systematic Review of Outcomes of Contralateral C7 Transfer for the Treatment of Traumatic Brachial Plexus Injury: Part 2. Donor-Site Morbidity

BACKGROUND

Although contralateral C7 (CC7) transfer has been widely used for treating traumatic brachial plexus injury, the safety of the procedure is questionable. The authors performed a systematic review to investigate the donor-site morbidity, including sensory abnormality and motor deficit, to guide clinical decision-making.

METHODS

A systematic review on (CC7) transfer for traumatic brachial plexus injury was performed for original articles in the PubMed and Embase databases. Patient demographic data and donor-site morbidity of (CC7) transfer, including incidence, recovery rate, and recovery time were extracted. The sensory abnormality areas and muscles involved in motor weakness were also summarized.

RESULTS

A total of 904 patients from 27 studies were reviewed. Overall, 74 percent of patients (668 of 897) experienced sensory abnormalities, and 98 percent (618 of 633) recovered to normal; the mean recovery time was 3 months. For motor function, 20 percent (118 of 592) had motor deficit after (CC7) transfer and 91 percent (107 of 117) regained normal motor function; the mean recovery time was 6 months. Sensory abnormality mainly occurred in the area of the hand innervated by the median nerve, whereas motor deficit most often involved muscles innervated by the radial nerve. There were 19 patients with long-term morbidity of the donor site in the studies.

CONCLUSIONS

The incidence of donor-site morbidity after (CC7) transfer was relatively high, and severe and long-term defects occurred occasionally. (CC7) transfer should be indicated only when other donor nerves are not available, and with a comprehensive knowledge of the potential risks.

Comparative study of intercostal nerve transfer to lower trunk and contralateral C7 root transfer in repair of total brachial plexus injury in rats

AIM

The aim of this study is to compare the treatment outcome of nerve transfer using intercostal nerves (ICNs) or contralateral C7 (cC7) root in rats.

METHODS

Ninety adult Sprague-Dawley rats were randomly divided into three groups of 30 each: group A (cC7 root transfer), group B (ICNs transfer), and group C (control). Electrophysiological examination, muscle tension test, neuromorphology, and muscle fiber cross-sectional area measurements obtained from the three groups were compared to evaluate neurotization outcome 4, 8, and 12 weeks postoperatively.

RESULTS

Median nerve regeneration and the flexor digitorum superficialis (FDS) muscle functional recovery of group B were worse than group A from comparison of both groups' parameters.

CONCLUSIONS

Neurotization of ICNs to the lower trunk is difficult to replace cC7 root transfer to the median nerve for restoration of hand function in total brachial plexus injury (BPI). Therefore, at present, the more important implication of the comparative study is that traditional cC7 root transfer remains the mainstay strategy to repair forearm flexor muscle function.

Donor-side morbidity after contralateral C-7 nerve transfer: results at a minimum of 6 months after surgery

OBJECT Donor-side morbidity associated with contralateral C-7 (CC7) nerve transfer remains controversial. The purpose of this study was to evaluate functional deficits in the donor limb resulting from prespinal route CC7 nerve transfer. METHODS A total of 63 patients were included. Forty-one patients had undergone CC7 nerve transfer surgery at least 6 months previously and were assigned to one of 2 groups based on the duration of postoperative follow-up. Group 1 (n = 21) consisted of patients who had undergone surgery between 6 months and 2 years previously, and Group 2 (n = 20) consisted of patients who had undergone surgery more than 2 years previously. An additional 22 patients who underwent CC7 nerve transfer surgery later than those in Groups 1 and 2 were included as a control group (Group 3). Results of preoperative testing in these patients and postoperative testing in Groups 1 and 2 were compared. Testing included subjective assessments and objective examinations. An additional 3 patients had undergone surgery more than 6 months previously but had severe motor weakness and were therefore evaluated separately; these 3 patients were not included in any of the study groups. RESULTS The revised Short-Form McGill Pain Questionnaire (SF-MPQ-2) was the only subjective test that showed a significant difference between Group 3 and the other 2 groups, while no significant differences were found in objective sensory, motor, or dexterity outcomes. The interval from injury to surgery for patients with a normal SF-MPQ-2 score in Groups 1 and 2 was significantly less than for those with abnormal SF-MFQ-2 scores (2.4 ± 1.1 months vs 4.6 ± 2.9 months, p = 0.002). The 3 patients with obvious motor weakness showed a tendency to gradually recover. CONCLUSIONS Although some patients suffered from long-term sensory disturbances, resection of the C-7 nerve had little effect on the function of the donor limb. Shortening preoperative delay time can improve sensory recovery of the donor limb.

The impact of different degrees of injured c7 nerve transfer: an experimental rat study

Background:

Ipsilateral C7 nerve transfer is an available procedure in C5C6 2-root avulsion injury of the brachial plexus. However, concomitant injury of a normal-looking C7 cannot be ruled out. The efficiency of a concomitant injury of C7 transfer was investigated.

Methods:

Forty-two Sprague-Dawley rats were randomly assigned to 5 groups. They all underwent a 2-stage procedure. In the first stage from dorsal spine approach, left C5 and C6 roots were avulsed and C7 was crushed with jeweler’s forceps with different degrees: group A (n = 6), C7 not injured; group B (n = 10), C7 crushed for 10 seconds; group C (n = 10), C7 crushed for 30 seconds; group D (n = 10), C7 doubly crushed for 60 seconds; and group E (n = 6), C7 transected and not repaired. Four weeks later in the second stage, the C7 was reexplored via volar approach, transected, and coapted to the musculocutaneous nerve. At 12 weeks following the nerve transfer, functional outcomes were assessed.

Results:

Grooming test, muscle weight, electromyography, and muscle tetanic contraction force all showed that the biceps muscles were significantly worse in group C (moderate crush) and group D (severe crush). Group B (mild crush) and group A (uninjured) showed no difference. Group E (C7 cut and not repaired) was the worst.

Conclusions:

An injured but grossly normal-looking ipsilateral C7 can be used as a motor source but with variable results. The result is directly proportional to the severity of injury, potentially implying that better results will be achieved when longer regeneration time is allowed.

Treatment options for brachial plexus injuries

The incidence of brachial plexus injuries is rapidly growing due to the increasing number of high-speed motor-vehicle accidents. These are devastating injuries leading to significant functional impairment of the patients. The purpose of this review paper is to present the available options for conservative and operative treatment and discuss the correct timing of intervention. Reported outcomes of current management and future prospects are also analysed.

Surgical treatment for total root avulsion type brachial plexus injuries by neurotization: a prospective comparison study between total and hemicontralateral C7 nerve root transfer

PURPOSE

We conducted a clinical study to evaluate the effects of neurotization, especially comparing the total contralateral C7 (CC7) root transfer to hemi-CC7 transfer, on total root avulsion brachial plexus injuries (BPI).

METHODS

Forty patients who received neurotization for BPI were enrolled in this prospective study. Group 1 (n = 20) received hemi-CC7 transfer for hand function, while group 2 (n = 20) received total-CC7 transfer. Additional neurotization included spinal accessory, phrenic, and intercostal nerve transfer for shoulder and elbow function. The results were evaluated with an average of 6 years follow-up.

RESULTS

Group 1 had fewer donor site complications (15%) than group 2 (45%); group 2 had significantly better hand M3 and M4 motor function (65%) than group 1 (30%; P = 0.02). There was no difference in sensory recovery. Significantly, better shoulder function was obtained by simultaneous neurotization on both suprascapular and axillary nerves.

CONCLUSIONS

Total-CC7 transfer had better hand recovery but more donor complications than hemi-CC7. Neurotization on both supra-scapular and axillary nerves improved shoulder recovery.

Outcome of contralateral C7 transfer to two recipient nerves in 22 patients with the total brachial plexus avulsion injury

The treatment of total brachial plexus avulsion injury is difficult with unfavorable prognosis. This report presents our experience on the contralateral C7 (CC7) nerve root transfer to neurotize two recipient nerves in the patients with total BPAI. Twenty-two patients underwent CC7 transfer to two target nerves in the injured upper limb. The patients' ages ranged from 13 to 48 years. The entire CC7 was transferred to pedicled ulnar nerve in the first stage. The interval between trauma and surgery ranged from 1 to 13 months. The ulnar nerve was transferred to recipients (median nerve and biceps branch or median nerve and triceps branch) at 2-13 months after first operation. The motor recovery of wrist and finger flexor to M3 or greater was achieved in 68.2% of patients, the sensory recovery of median nerve area recovered to S3 or greater in 45.5% of patients. The functional recovery of elbow flexor to M3 or greater was achieved in 66.7% of patients with repair of biceps branch and 20% of patients with repair of the triceps branch (P < 0.05). There were no statistical differences in median nerve function recovery at comparisons of the age younger and older than 20-years-old and the intervals between trauma and surgery. In conclusion, the use of CC7 transfer for repair two recipient nerves might be an option for treatment of total BPAI. The functional recovery of the repaired biceps branch appeared to be better than that of the triceps branch.

Contralateral C7 nerve transfer with direct coaptation to restore lower trunk function after traumatic brachial plexus avulsion

BACKGROUND

Contralateral C7 nerve transfer to the median nerve has been used in an attempt to restore finger flexion in patients with total brachial plexus avulsion injury. However, the results have not been satisfactory mainly because of the requirement to use a long bridging nerve graft, which causes an extended nerve regeneration process and irreversible muscle atrophy. A new procedure involving contralateral C7 nerve transfer via a modified prespinal route and direct coaptation with the injured lower trunk is presented here.

METHODS

Contralateral C7 nerve transfer via the modified prespinal route and direct coaptation with the injured lower trunk was performed in seventy-five patients with total brachial plexus avulsion injury. Thirty-five required humeral shortening osteotomy (3 to 4.5 cm) in order to accomplish the direct coaptation. The contralateral C7 nerve was also transferred to the musculocutaneous nerve through the bridging medial antebrachial cutaneous nerve arising from the lower trunk in forty-seven of the seventy-five patients. Recovery of finger, wrist, and elbow flexion was evaluated with use of the modified British Medical Research Council muscle grading system.

RESULTS

The mean follow-up period (and standard deviation) was 57 ± 6 months (range, forty-eight to seventy-eight months). Motor function with a grade of M3+ or greater was attained in 60% of the patients for elbow flexion, 64% of the patients for finger flexion, 53% of the patients for thumb flexion, and 72% of the patients for wrist flexion.

CONCLUSIONS

Contralateral C7 nerve transfer via a modified prespinal route and direct coaptation with the injured lower trunk decreases the distance for nerve regeneration in patients with total brachial plexus avulsion injury. There was satisfactory recovery of finger flexion and wrist flexion in this series. In addition, contralateral C7 nerve transfer was successfully used to repair two different target nerves: the lower trunk and the musculocutaneous nerve.

Minimum 4-year follow-up on contralateral C7 nerve transfers for brachial plexus injuries

PURPOSE

Contralateral C7 (CC7) transfer for brachial plexus injuries (BPI) can benefit finger sensation but remains controversial regarding restoration of motor function. We report our 20-year experience using CC7 transfer for BPI, all of which had at least 4 years of follow-up.

METHODS

A total of 137 adult BPI patients underwent CC7 transfer from 1989 to 2006. Of these patients, 101 fulfilled the inclusion criteria for this study. A single surgeon performed all surgeries. A vascularized ulnar nerve graft, either pedicled or free, was used for CC7 elongation. The vascularized ulnar nerve graft was transferred to the median nerve (group 1, 1 target) in 55 patients, and to the median and musculocutaneous nerves (group 2, 2 targets) in 23 patients. In another 23 patients (group 3, 2 targets, 2 stages), the CC7 was transferred to the median nerve (17 patients) or to the median and musculocutaneous nerve (6 patients) during the first stage, followed by functioning free muscle transplantation for finger flexion.

RESULTS

We considered finger flexion strength greater or equal to M3 to be a successful functional result. Success rates of CC7 transfer were 55%, 39%, and 74% for groups 1, 2, and 3, respectively. In addition, the success rate for recovery of elbow flexion (strength M3 or better) in group 2 was 83%.

CONCLUSIONS

In reconstruction of total brachial plexus root avulsion, the best option may be to adopt the technique of using CC7 transfer to the musculocutaneous and median nerve, followed by FFMT in the early stage (18 mo or less) for finger flexion. Such a technique can potentially improve motor recovery of elbow and finger flexion in a shorter rehabilitation period (3 to 4 y) and, more importantly, provide finger sensation to the completely paralytic limb.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic II.

Hemi-contralateral C7 transfer in traumatic brachial plexus injuries: outcomes and complications

BACKGROUND

In brachial plexus injuries with nerve root avulsions, the options for nerve reconstruction are limited. In select situations, half or all of the contralateral C7 (CC7) nerve root can be transferred to the injured side for brachial plexus reconstruction. Although encouraging results have been reported, CC7 transfer has not gained universal popularity. The purpose of this study was to critically evaluate hemi-CC7 transfer for restoration of shoulder function or median nerve function in patients with severe brachial plexus injury.

METHODS

A retrospective review of all patients with traumatic brachial plexus injury who had undergone hemi-CC7 transfer at a single institution during an eight-year period was performed. Complications were evaluated in all patients regardless of the duration of follow-up. The results of electrodiagnostic studies and modified British Medical Research Council (BMRC) motor grading were reviewed in all patients with more than twenty-seven months of follow-up.

RESULTS

Fifty-five patients with traumatic brachial plexus injury underwent hemi-CC7 transfer performed between 2001 and 2008 for restoration of shoulder function or median nerve function. Thirteen patients who underwent hemi-CC7 transfer to the shoulder and fifteen patients who underwent hemi-CC7 transfer to the median nerve had more than twenty-seven months of follow-up. Twelve of the thirteen patients in the shoulder group demonstrated electromyographic evidence of reinnervation, but only three patients achieved M3 or greater shoulder abduction motor function. Three of the fifteen patients in the median nerve group demonstrated electromyographic evidence of reinnervation, but none developed M3 or greater composite grip. All patients experienced donor-side sensory or motor changes; these were typically mild and transient, but one patient sustained severe, permanent donor-side motor and sensory losses.

CONCLUSIONS

The outcomes of hemi-CC7 transfer for restoration of shoulder motor function or median nerve function following posttraumatic brachial plexus injury do not justify the risk of donor-site morbidity, which includes possible permanent motor and sensory losses.

Contralateral C7 nerve root transfer to neurotize the upper trunk via a modified prespinal route in repair of brachial plexus avulsion injury

PURPOSE

In this report, we present our experience on the repair of brachial plexus root avulsion injuries with the use of contralateral C7 nerve root transfers with nerve grafting through a modified prespinal route.

METHODS

The outcomes of the contralateral C7 nerve root transfer to neurotize the upper trunk and C5/C6 nerve roots of the total or near total brachial plexus nerve root avulsion injury in a series of 41 patients were evaluated. The contralateral C7 nerve root that was dissected to the distal end of the divisions, along with the sural nerve graft, were placed underneath the anterior scalene and longus colli muscles, and then passed through the retro-esophageal space to neurotize the recipient nerve. The mean length of the dissected contralateral C7 nerve root was 6.5 ± 0.7 cm, and the mean length of sural nerve graft was 6.8 ± 1.9 cm. The suprascapular nerve was neurotized additionally by the phrenic nerve or the terminal motor branch of accessory nerve in some patients.

RESULTS

The mean length of the follow-up was 47.2 ± 14.5 months. The muscle strength was graded M4 or M3 for the biceps muscle in 85.4% of patients, for the deltoid muscle in 82.9% of patients, and for the upper parts of pectoral major in 92.7% of patients. The functional recovery of shoulder abduction in the patients with the additional suprascapular nerve neurotization was remarkably improved.

CONCLUSIONS

The modified prespinal route could significantly reduced the length of nerve graft in the contralateral C7 nerve root transfer to the injured upper trunk in brachial plexus root avulsion injury, and it may improve the functional outcomes, which deserves further investigations.

Comparison of nerve transfers and nerve grafting for traumatic upper plexus palsy: a systematic review and analysis

BACKGROUND

In treating patients with brachial plexus injury, there are no comparative data on the outcomes of nerve grafts or nerve transfers for isolated upper trunk or C5-C6-C7 root injuries. The purpose of our study was to compare, with systematic review, the outcomes for modern intraplexal nerve transfers for shoulder and elbow function with autogenous nerve grafting for upper brachial plexus traumatic injuries.

METHODS

PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials were searched for studies in which patients had surgery for traumatic upper brachial plexus palsy within one year of injury and with a minimum follow-up of twelve months. Strength and shoulder and elbow motion were assessed as outcome measures. The Fisher exact test and Mann-Whitney U test were used to compare outcomes, with an alpha level of 0.05.

RESULTS

Thirty-one studies met the inclusion criteria. Two hundred and forty-seven (83%) and 286 (96%) of 299 patients with nerve transfers achieved elbow flexion strength of grade M4 or greater and M3 or greater, respectively, compared with thirty-two (56%) and forty-seven (82%) of fifty-seven patients with nerve grafts (p < 0.05). Forty (74%) of fifty-four patients with dual nerve transfers for shoulder function had shoulder abduction strength of grade M4 or greater compared with twenty (35%) of fifty-seven patients with nerve transfer to a single nerve and thirteen (46%) of twenty-eight patients with nerve grafts (p < 0.05). The average shoulder abduction and external rotation was 122° (range, 45° to 170°) and 108° (range, 60° to 140°) after dual nerve transfers and 50° (range, 0° to 100°) and 45° (range, 0° to 140°) in patients with nerve transfers to a single nerve.

CONCLUSIONS

In patients with demonstrated complete traumatic upper brachial plexus injuries of C5-C6, the pooled international data strongly favors dual nerve transfer over traditional nerve grafting for restoration of improved shoulder and elbow function. These data may be helpful to surgeons considering intraoperative options, particularly in cases in which the native nerve root or trunk may appear less than optimal, or when long nerve grafts are contemplated.

Modified C7 neurotization for the treatment of obstetrical brachial plexus palsy

Contralateral C7 transfer is used rarely in infants with obstetrical brachial plexus palsy (OBPP). We aimed to determine the efficacy of contralateral C7 transfer to two different recipient nerves in infants with OBPP. Between 2001 and 2005, 9 infants with brachial plexus root avulsions underwent nerve reconstruction using a modified C7 neurotization technique. In this procedure, the contralateral C7 root was transferred to both the musculocutaneous nerve and the median nerve on the affected side. The strength of the biceps muscles increased to M3 or M4 in 7 patients and to M2 in 2 patients. The median nerve transfers led to regained motor function and strength of wrist and finger flexors with improvement to M3 or M4 in 5 patients. All patients showed notable gains of sensory function. Contralateral C7 transfer to two different recipient nerves is a feasible and efficient approach in infants with OBPP.

Long-range plasticity between intact hemispheres after contralateral cervical nerve transfer in humans

OBJECT

Peripheral nerve injury in a limb usually causes intrahemispheric functional reorganization of the contralateral motor cortex. Recently, evidence has been emerging for significant interhemispheric cortical plasticity in humans, mostly from studies of direct cortical damage. However, in this study, a long-range interhemispheric plasticity was demonstrated in adults with brachial plexus avulsion injury (BPAI) who had received a contralateral cervical nerve transfer, and this plasticity reversed the BPAI-induced intrahemispheric cortical reorganization.

METHODS

In this study, 8 adult male patients with BPAI were studied using PET scanning.

RESULTS

The results indicated that the right somatomotor cortices, which may contribute to the control of the injured limb before brachial plexus deafferentation, still played an important role when patients with BPAI tried to move their affected limbs, despite the fact that the contralateral C-7 nerve transfer had been performed and the peripheral output had changed dramatically. Such findings are consistent with the results of the authors' previous animal study.

CONCLUSIONS

The brain may try to restore the control of an injured limb to its original cortex area, and a complicated change of peripheral pathway also can induce long-range interhemispheric cortical reorganization in human motor cortex.

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.

Contralateral C7 transfer in adult plexopathies

In the current study, a retrospective review of 56 patients with posttraumatic root avulsion brachial plexus injuries who underwent contralateral C7 transfer using the selective contralateral C7 technique is presented. The intraoperative findings of the involved brachial plexus, the surgical technique of preparation of the donor C7 nerve root, and the various neurotization procedures are reported. The surgical outcomes as well as the potential adverse effects of the procedure are analyzed. We conclude from this study that the selective contralateral C7 technique is a safe procedure that can be applied successfully for simultaneous reconstruction of several different contralateral muscle targets or for neurotization of cross chest nerve grafts for future free muscle transplantation.

Heterotopic nerve transfers: recent trends with expanding indication

There has been increasing enthusiasm for heterotopic nerve transfers for brachial plexus palsy as well as peripheral mononeural dysfunction. The concept of nerve transfer surgery is not new; the first publications on the topic date back to the early 1900s. A wide variety of potential donor nerves are available including the intercostal nerves, the spinal accessory nerve, the phrenic nerve, the ipsilateral medial pectoral nerve, partial ulnar nerve, partial median nerve, thoracodorsal nerve, radial nerve to the triceps, and the ipsilateral C7 or the contralateral C7 nerve roots. Treatment strategies include avoidance of interposed nerve grafting, isolated motor recipient nerve, early transfer, neurorrhaphy close to target motor end plates, and similar diameter between donor nerve and recipient nerves.

Neuronal survival, regeneration and musclemorphology after posterior C7 nerve transfer:An experimental study

C7 nerve transfer has been widely used in treating brachial plexus avulsion injuries. Little is known regarding the survival and regeneration of C7 motor and sensory neurons including their morphological changes after this procedure and also the possible change of muscle fibre phenotype. In this experimental study, the posterior division of C7 nerve was transferred to the musculocutaneous nerve ipsilaterally, and using fluorescent tracing techniques, the C7 spinal cord segment and dorsal root ganglion were found to contain 630.9 +/- 86.7 motor neurons and 3916.0 +/- 517.3 sensory neurons, respectively. Six months following transfer, 90% of the motor neurons and 78% of the sensory neurons survived and approximately 40% of them had regenerated and all displayed normal soma size. After posterior C7 transfer and reinnervation, the target muscles showed a percentage pattern of distribution and mean fibre diameters similar to those seen in normal biceps muscle. The present study suggests that the posterior C7 nerve transfer provides sufficient number of neurons and satisfactory results for regeneration to obtain an acceptable functional recovery.

Nerve root distribution of deltoid and biceps brachii muscle in cervical spondylotic myelopathy: a potential risk factor for postoperative shoulder muscle weakness after posterior decompression

To investigate the nerve root distribution of deltoid and biceps brachii muscle, compound muscle action potentials (CMAPs) were recorded intraoperatively following nerve root stimulation in cervical spondylotic myelopathy. A total of 19 upper limbs in 12 patients aged 55-72 years (mean, 65.5 years) with cervical spondylotic myelopathy were examined. CMAPs were recorded from deltoid and biceps brachii muscle following C5 and C6 root stimulation. Although both C5 and C6 roots were innervated for deltoid and biceps brachii muscle in all subjects, the amplitude ratio of CMAPs (C5/C6) differed individually depending on the symptomatic intervertebral levels of the spinal cord. The C5 root predominantly innervated both deltoid and biceps brachii in patients with symptomatic cord lesions at the C4-C5 intervertebral level compared to patients with symptomatic cord lesions at the C5-C6 intervertebral level. Although no patients sustained postoperative radiculopathy in our study, severe weakness and unfavorable recovery are expected when the C5 root in patients with C4-C5 myelopathy is damaged. From the electrophysiological aspect, C4-C5 cord lesions are likely to be a potential risk factor for postoperative shoulder muscle weakness in patients with compressive cervical myelopathy.

Update on management of pediatric brachial plexus palsy

This manuscript will review the literature and focus on the present controversies regarding natural history, microsurgical treatment, and secondary shoulder reconstructive surgery in infants with brachial plexus birth palsies. Surgical indications, expected outcomes and complications will be addressed. The controversy regarding microsurgery timing in extra-foraminal ruptures will be addressed in detail. The developments in assessment and care of glenohumeral deformity with magnetic resonance imaging scans, arthroscopic and open reductions, and tendon transfers about the shoulder will be discussed. Recommendations for microsurgery and shoulder reconstruction will be based on the present evidence from the literature.

Update on management of pediatric brachial plexus palsy

This manuscript will review the literature and focus on the present controversies regarding the natural history, microsurgical treatment, and secondary shoulder reconstructive surgery in infants with brachial plexus birth palsies. Surgical indications, expected outcomes, and complications will be addressed. The controversy regarding the timing of microsurgery in extraforaminal ruptures will be addressed in detail. The developments in assessment and care of glenohumeral deformity with magnetic resonance imaging scans, arthroscopic and open reductions, and tendon transfers about the shoulder will be discussed. Recommendations for microsurgery and shoulder reconstruction will be based on the present evidence from the literature.

Planning brachial plexus surgery: treatment options and priorities

Brachial plexus injuries are devastating and usually result from high-energy trauma in young patients. Clinicians treating brachial plexus injuries need to recognize the pattern of injury presenting in each patient. Most injuries can be described as either supraclavicular or infraclavicular. The specific injury is determined by means ofa precise workup, including careful physical examination, electrodiagnostic studies, and imaging studies; a thorough workup is essential for successful preoperative planning. Priorities need to be identified and matched with available resources in each patient. A growing number of good treatment alternatives are available. Finally,counseling patients toward realistic expectations isa critical component of preparation for surgery.

Nerve transfers for severe brachial plexus injuries: a review

Nerve transfer procedures are increasingly performed for repair of severe brachial plexus injury (BPI), in which the proximal spinal nerve roots have been avulsed from the spinal cord. The procedure essentially involves the coaption of a proximal foreign nerve to the distal denervated nerve to reinnervate the latter by the donated axons. Cortical plasticity appears to play an important physiological role in the functional recovery of the reinnervated muscles. The author describes the general principles governing the successful use of nerve transfers. One major goal of this literature review is to provide a comprehensive survey on the numerous intra- and extraplexal nerves that have been used in transfer procedures to repair the brachial plexus. Thus, an emphasis on clinical outcomes is provided throughout. The second major goal is to discuss the role of candidate nerves for transfers in the surgical management of the common severe brachial plexus problems encountered clinically. It is hoped that this review will provide the treating surgeon with an updated list, indications, and expected outcomes involving nerve transfer operations for severe BPIs.

The Surgical Treatment of Obstetric Brachial Plexus Palsy

Learning Objectives: After studying this article, the participant should be able to: 1. Understand the natural history of obstetric brachial plexus injury with an emphasis on clinicopathologic features. 2. Develop an awareness of the indications and timing for both nonsurgical and surgical treatment. 3. Acquire knowledge of the current methodologies involved in primary and secondary brachial plexus reconstruction.Obstetric brachial plexus palsy is a potentially devastating form of cervical nerve injury that occurs in 0.38 to 2.6 births per thousand. In this review, we discuss fundamental clinicopathology and delve into the indications and methods of both nonsurgical and surgical strategies. An analysis of the major techniques of reconstruction is placed within the context of historical trends and a contemporaneous survey of the literature. On this basis, and given our own 12-year experience (with 415 surgically treated patients), several general conclusions can be made: (1) Early surgical intervention (3 to 6 months) is essential to optimizing long-term outcome in patients who have not had return of function in critical muscle groups. At Texas Children’s Hospital, we have developed an efficient multidisciplinary approach to primary brachial plexus exploration and reconstruction by integrating the neurosurgical, physical medicine and rehabilitation, neurologic, and plastic surgical services. (2) Secondary residual deformities—most notably the quintessential internal rotation and adduction deformity of the upper extremity—arise from both prolonged conservative management and failed surgical treatment; however, an effective armamentarium of reconstructive options (tendon transfers, muscle releases, neurotizations, and free muscle flap transplantations) has evolved to markedly improve the functional status of these patients. (3) Innovative reconstructive approaches, including nerve grafting, intraplexal and extraplexal neurolysis, and nerve transfers, should be well planned and applied for maximal functional recovery of the extremity. Priorities for the restoration of hand function, elbow flexion, and shoulder abduction should be the goal.

Les paralysies du plexus brachial de l’adulte par lésions radiculaires, conception générale, orientations thérapeutiques et résultats

In post-traumatic brachial plexus lesions in adults, early repair will necessitate a variety of nerve grafting and nerve transfer procedures. In complete palsies, a graft is performed from a radicular stump, using intercostal nerve transfers, partial cross C7 transfer, and the distal spinal accessory nerve. This will provide elbow flexion and extension in 75% of cases, and shoulder abduction or rotation in 50% of cases. In the upper type palsies, ulnar-biceps transfer is the standard procedure. Grafting from a ruptured cervical root, when available, is performed to reanimate the shoulder. In C5 C6 and C7 palsies, extension of the wrist and fingers is provided by tendon transfers. In chronic palsies, elbow flexion and extension loss is treated by means of free muscle transfers, (latissimus dorsi or gracilis) combined with nerve transfers (intercostals or spinal accessory). Secondary procedures are routinely necessary following recovery of elbow flexion. For the shoulder-humeral shaft osteotomy or fusion, for the hand-cosmetic fusion of the wrist and distal radio-ulnar joint in the prone position, or palliative treatment in case of partial recovery. For such weak "plexic hands", we have developed a specific hierarchical functional scale, useful for surgical decisions.

Extensive somatosensory innervation in infants with obstetric brachial palsy

In the pre-operative screening of infants with obstetric brachial palsy (OBP), the results of routine electromyography are often overly optimistic when compared to the peri-operative findings. This prompted us to include investigation of the sensory innervation of these infants using the N20 (the first cortical response to a peripheral stimulation) of the somatosensory evoked potentials (SSEP). Three to seven months after birth, SSEP were recorded at the skull after stimulation of the thumb and middle finger in infants with obstetric rupture of the upper trunk or avulsion of roots C5, C6, or C7, and in whom no clinical improvement of motor function was observed in the biceps brachii and deltoid muscles. In most infants, a normal N20 could be evoked, indicating the existence of peripheral sensory pathways. From the thumb, these sensory pathways would necessarily bypass the upper trunk and dorsal roots of spinal nerves C5 and C6, and from the middle finger bypass the middle trunk and dorsal root C7, before extending into the dorsal column and projecting toward the thalamus and cerebral cortex. These data suggest that in infancy the segmental sensory innervation of the hand is more diverse than is described in most textbooks.

The prespinal route in contralateral C7 nerve root transfer for brachial plexus avulsion injuries

Contralateral C7 nerve root transfer for brachial plexus injury is described, passing the nerve through a subcutaneous tunnel on the anterior surface of the neck and chest. We recommend passing the nerve graft through the retropharyngeal space. This route has the benefits of a simpler dissection, a shorter distance and protected placement of the graft. It has been used in one clinical case.

Hemi-contralateral C7 transfer to median nerve in the treatment of root avulsion brachial plexus injury

Because of the poor clinical results in achieving hand function in patients with complete brachial plexus root avulsion with other nerve transfers, we evaluated 111 patients prospectively to evaluate the technique of the hemi-contralateral C7 transfer to the median nerve. The transfer was performed as a primary procedure in 62 patients and as a secondary procedure in additional 49 patients. Twenty-one of the 62 patients in the primary group had sufficient follow-up (at least 3 years) to assess the motor and sensory recovery in the median nerve. The adverse effects of the operation were also analyzed in all 111 patients. Six of the 21 (29%) patients obtained M3 and 4 (19%) experienced M2 recovery of the wrist and finger flexors. Ten (48%) patients obtained S3 and 7 (33%) had S2 recovery in the median nerve area. The rate of the advancing Tinel's sign was markedly different between those achieving M3 function and the remaining patients. Although the age of the patient did not correlate with outcome, patients aged 18 and younger had the best motor recovery (ie, achieving M3 function in 3 of 6 cases). There was no correlation between the timing of the surgery after the initial injury, medical comorbidities, and clinical outcome. After surgery 108 of 111 (97%) patients experienced temporary paresthesia in the median nerve area, which resolved by an average of 2.8 months. Three (3%) patients had motor weakness of the donor limb; this resolved completely in 2 patients and left a mild deficit in wrist extension in 1 patient.

Lowest number of brachial plexus nerve roots required for maintaining normal limb function--an experimental study

Rat models with different division of nerve roots of the brachial plexus were designed to assess whether single or two nerve roots of the contralateral normal brachial plexus can be divided as donor nerves in treatment of brachial plexus root avulsion. Two hundred and fifty-two SD rats were randomly divided into 13 groups, i.e. five groups with single nerve root division, seven groups with two nerve roots division, and one group with three nerve roots division. Post-operative evaluation by electroneurophysiology and muscular histology was performed at two weeks and two months. Results showed that in groups with single nerve root division, the experimental limb function did not show an apparent damage; in groups with non-neighbouring two nerve roots cutting, it did show a harmful repercussions on the limb at two weeks, but most of them recovered to normal at two months; in groups with neighbouring two nerve roots division and with non-neighbouring three nerve root cutting, the limb function showed a persistent damage. In conclusion, division of nerve root alone or even non- neighbouring two nerve roots of the brachial plexus did not affect the forelimb function of the rat permanently.