Root Avulsion Brachial Plexus Injuries Research Articles

Melatonin combined with chondroitin sulfate ABC promotes nerve regeneration after root-avulsion brachial plexus injury.

After nerve-root avulsion injury of the brachial plexus, oxidative damage, inflammatory reaction, and glial scar formation can affect nerve regeneration and functional recovery. Melatonin (MT) has been shown to have good anti-inflammatory, antioxidant, and neuroprotective effects. Chondroitin sulfate ABC (ChABC) has been shown to metabolize chondroitin sulfate proteoglycans and can reduce colloidal scar formation. However, the effect of any of these drugs alone in the recovery of nerve function after injury is not completely satisfactory. Therefore, this experiment aimed to explore the effect and mechanism of combined application of melatonin and chondroitin sulfate ABC on nerve regeneration and functional recovery after nerve-root avulsion of the brachial plexus. Fifty-two Sprague-Dawley rats were selected and their C5-7 nerve roots were avulsed. Then, the C6 nerve roots were replanted to construct the brachial plexus nerve-root avulsion model. After successful modeling, the injured rats were randomly divided into four groups. The first group (injury) did not receive any drug treatment, but was treated with a pure gel-sponge carrier nerve-root implantation and an ethanol-saline solution via intraperitoneal (i.p.) injection. The second group (melatonin) was treated with melatonin via i.p. injection. The third group (chondroitin sulfate ABC) was treated with chondroitin sulfate ABC through local administration. The fourth group (melatonin + chondroitin sulfate ABC) was treated with melatonin through i.p. injection and chondroitin sulfate ABC through local administration. The upper limb Terzis grooming test was used 2-6 weeks after injury to evaluate motor function. Inflammation and oxidative damage within 24 hours of injury were evaluated by spectrophotometry. Immunofluorescence and neuroelectrophysiology were used to evaluate glial scar, neuronal protection, and nerve regeneration. The results showed that the Terzis grooming-test scores of the three groups that received treatment were better than those of the injury only group. Additionally, these three groups showed lower levels of C5-7 intramedullary peroxidase and malondialdehyde. Further, glial scar tissue in the C6 spinal segment was smaller and the number of motor neurons was greater. The endplate area of the biceps muscle was larger and the structure was clear. The latency of the compound potential of the myocutaneous nerve-biceps muscle was shorter. All these indexes were even greater in the melatonin + chondroitin sulfate ABC group than in the melatonin only or chondroitin sulfate ABC only groups. Thus, the results showed that melatonin combined with chondroitin sulfate ABC can promote nerve regeneration after nerve-root avulsion injury of the brachial plexus, which may be achieved by reducing oxidative damage and inflammatory reaction in the injury area and inhibiting glial scar formation.

Is Pseudomeningocele an Absolute Sign of Root Avulsion Brachial Plexus Injury?

The finding of pseudomeningocele from cervical myelogram is widely accepted as a pathognomonic sign for diagnosing root avulsion in brachial plexus injury. In general, motor power in this setting should be absent. However, in clinical practice, we observed that motor power in some patients was still preserved. The objective of this study is to evaluate the accuracy of pseudomeningocele from cervical myelogram for predicting root avulsion in brachial plexus injury. We retrospectively reviewed 201 patients with brachial plexus injury from 2007-2011. Four patients were excluded due to open wound injury. Motor power of the key muscle of each nerve root was evaluated by skilled hand surgeons. All cervical myelogram was interpreted by radiologists. Sensitivities, specificities, positive predictive values and negative predictive values were calculated with 95% confidence interval. Thirty and 29% of pseudomeningocele occurred at C7 and C8 level, respectively. The sensitivity of pseudomeningocele of each root from C5 to T1 was low (range, 10-62%). The specificity was high only at C5 (91%) and T1 (96.2%). Over 20% of patients with pseudomeningocele at C6-8 levels had some motor function. The initial muscle power of these patients was M1 or M2 and 70% of them recovered to at least M3 at the final follow-up. Pseudomeningocele is not an absolute sign for diagnosing of root avulsion in brachial plexus injury due to its high false positive rate when compared with preoperative motor function of each root. Careful examination of the key muscle of each root is extremely crucial to prevent unnecessary operation on that cervical nerve root.

Free Functioning Gracilis Muscle Transfer With and Without Simultaneous Intercostal Nerve Transfer to Musculocutaneous Nerve for Restoration of Elbow Flexion After Traumatic Adult Brachial Pan-Plexus Injury

After complete 5-level root avulsion brachial plexus injury, the free-functioning muscle transfer (FFMT) and the intercostal nerve (ICN) to musculocutaneous nerve (MCN) transfer are 2 potential reconstructive options for restoration of elbow flexion. The aim of this study was to determine if the combination of the gracilis FFMT and the ICN to MCN transfer provides stronger elbow flexion compared with the gracilis FFMT alone. Sixty-five patients who underwent the gracilis FFMT only (32 patients) or the gracilis FFMT in addition to the ICN to MCN transfer (33 patients) for elbow flexion after a pan-plexus injury were included. The 2 groups were compared with respect to postoperative elbow flexion strength according to the modified British Medical Research Council grading system as well as preoperative and postoperative Disability of the Arm, Shoulder, and Hand scores. Two subgroup analyses were performed for the British Medical Research Council elbow flexion strength grade: FFMT neurotization (spinal accessory nerve vs ICN) and the attachment of the distal gracilis tendon (biceps tendon vs flexor digitorum profundus/flexor pollicis longus tendon). The proportion of patients reaching the M3/M4 elbow flexion muscle grade were similar in both groups (FFMT vs FFMT+ ICN to MCN transfer). Statistically significant improvement in postoperative Disability of the Arm, Shoulder, and Hand score was found in the FFMT+ ICN to MCN transfer group but not in the FFMT group. There was a significant difference between gracilis to biceps (M3/M4= 52.6%) and gracilis to FDP/flexor pollicis longus (M3/M4= 85.2%) tendon attachment. The use of the ICN to MCN transfer associated with the FFMT does not improve the elbow flexion modified British Medical Research Council grade, although better postoperative Disability of the Arm, Shoulder, and Hand scores were found in this group. The more distal attachment of the gracilis FFMT tendon may play an important role in elbow flexion strength. Therapeutic IV.

Comparative Study of Phrenic and Intercostal Nerve Transfers for Elbow Flexion After Global Brachial Plexus Injury

Objective: The aim of this study was to compare phrenic and intercostal nerve transfers for elbow flexion after global brachial plexus injury. Methods: A retrospective review of 33 patients treated with phrenic and intercostal nerve transfer for elbow flexion in posttraumatic global root avulsion brachial plexus injury was carried out. Phrenic nerve transfer group: phrenic nerve was transferred to anterolateral bundle of anterior division of upper trunk (23 patients); intercostal nerve transfer group: three intercostal nerves were coapted to the anterolateral bundles of musculocutaneous nerve. The British Medical Research Council (MRC) grading system, angle of elbow flexion, and electromyography (EMG) were used to evaluate the recovery of elbow flexion at least 3 years after surgery. Results: The efficiency of motor function in phrenic nerve transfer group was 83%, while it was 70% in intercostal nerve transfer group. The 2 groups were not statistically different in terms of MRC grade ( P = .646) and EMG results ( P = .646). The outstanding rates of angle of elbow flexion were 48% and 40% in phrenic and intercostal nerve transfer groups, respectively. There was no significant difference of outstanding rates in angle of elbow flexion between the 2 groups. Conclusion: Phrenic nerve transfer had a higher proportion of good prognosis for elbow flexion than intercostal nerve transfer, but the effective and outstanding rate had no significant difference for biceps reinnervation between the 2 groups according to MRC grading, angle of elbow flexion, and EMG.

Evaluation of Protective Sensation after Hemi-contralateral C7 Nerve Root Transfer to Median Nerve in Total Root Avulsion Brachial Plexus Injury: Level 4 Evidence

There is no financial information to disclose. Hemi-contralateral C7 nerve root (hemi-CC7) transfer to median nerve has been done in total root avulsion brachial plexus injury to restore protective sensation of the hand and finger flexion. The hypothesis of this study is that hemi-CC7 transfer to median nerve can provide useful protective sensation of the hand in the brachial plexus injury patients. Brachial plexus injury patients who underwent hemi-CC7 transfer to median nerve from 2000 to 2012 at a single institution were evaluated with multimodality of sensory evaluation, including simple light touch, the Semmes-Weinstein monofilament testing, 2-point discrimination and vibration perception threshold. The measurements performed at least 4 years after the operation. Fifty patients underwent hemi-CC7 transfer to median nerve using a vascularized ulnar nerve graft were evaluated. The mean age at the time of injury was 25 years. The average time from injury to surgery was 9 months (range, 2-25 mo.). The average postoperative follow-up time was 89 months (range, 48 – 191 mo.). Nine patients (18%) showed response with the simple light touch. Sixteen patients (32%) could sense the Semmes-Weinstein monofilament test. Five patients recognized the 4.56 filament and 11 patients recognized the 6.65 filament. No patients developed 2-point discrimination sense less than 15mm. No patient responded to vibration testing with 256 Hz tuning fork. Nine patients (18%) had S3 recovery, according to British Medical Research Council grading system. •According to monofilament testing and 2-point discrimination interpretation, no patient had the sensory recovery at the level of protective sensation.•Previous studies reported recovery of the sensation more than 80% of the patients, however, most of them had difficulty to localize the stimulus.•Our study used multimodality sensory testing to evaluate the quality of neural recovery.

Outcome of contralateral C7 nerve transferring to median nerve

Background Contralateral C7 (cC7) transfer had been widely used in many organizations in the world, but the outcomes were significantly different. So the purpose of the study was to evaluate the outcome of patients treated with cC7 transferring to median nerve and to determine the factors affecting the outcome of this procedure. Methods A retrospective review of 51 patients with total root avulsion brachial plexus injuries who underwent cC7 transfer was conducted. All of the surgeries were performed with two surgery stages and median nerve was the recipient nerve. The cC7 nerve was used in three different ways. The entire C7 root was used in 11 patients; the posterior division together with the lateral part of the anterior division was used in 15 patients; the anterior or the posterior division alone was used in 25 patients. The mean follow-up period was 6.9 years. Results The efficiency of the surgery in these 51 patients was 49.02% in motor and 62.75% in sensory function. The patients with entire C7 root transfer obtained significantly better recovery in both motor and sensory function than the patients with partial C7 transfer. The best function recovery could be induced if the interval between the two surgery stages was 4-8 months. Conclusions cC7 transfer is an effective procedure in repairing median nerve. But using the entire C7 root transfer can obtain better recovery; so we emphasize using the entire root as the donor. The optimal interval between two surgery stages is 4-8 months.

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. © 2013 The Authors. Microsurgery published by Wiley Periodicals, Inc. Microsurgery 34:91–101, 2014.

Comparative study of phrenic nerve transfers with and without nerve graft for elbow flexion after global brachial plexus injury

BackgroundNerve transfer is a valuable surgical technique in peripheral nerve reconstruction, especially in brachial plexus injuries. Phrenic nerve transfer for elbow flexion was proved to be one of the optimal procedures in the treatment of brachial plexus injuries in the study of Gu et al. ObjectiveThe aim of this study was to compare phrenic nerve transfers with and without nerve graft for elbow flexion after brachial plexus injury. MethodsA retrospective review of 33 patients treated with phrenic nerve transfer for elbow flexion in posttraumatic global root avulsion brachial plexus injury was carried out. All the 33 patients were confirmed to have global root avulsion brachial plexus injury by preoperative and intraoperative electromyography (EMG), physical examination and especially by intraoperative exploration. There were two types of phrenic nerve transfers: type1 – the phrenic nerve to anterolateral bundle of anterior division of upper trunk (14 patients); type 2 – the phrenic nerve via nerve graft to anterolateral bundle of musculocutaneous nerve (19 patients). Motor function and EMG evaluation were performed at least 3 years after surgery. ResultsThe efficiency of motor function in type 1 was 86%, while it was 84% in type 2. The two groups were not statistically different in terms of Medical Research Council (MRC) grade (p=1.000) and EMG results (p=1.000). There were seven patients with more than 4 month's delay of surgery, among whom only three patients regained biceps power to M3 strength or above (43%). A total of 26 patients had reconstruction done within 4 months, among whom 25 patients recovered to M3 strength or above (96%). There was a statistically significant difference of motor function between the delay of surgery within 4 months and more than 4 months (p=0.008). ConclusionPhrenic nerve transfers with and without nerve graft for elbow flexion after brachial plexus injury had no significant difference for biceps reinnervation according to MRC grading and EMG. A delay of the surgery after the 4 months might imply a bad prognosis for the recovery of the function.

Outcome after transfer of intercostal nerves to the nerve of triceps long head in 25 adult patients with total brachial plexus root avulsion injury

The intercostal nerves (ICNs) have been used to repair the triceps branch in some organizations in the world, but the reported results differ significantly. The effect of this procedure requires evaluation. Thus, this study aimed to evaluate the outcome of ICN transfer to the nerve of the long head of the triceps muscle and to determine the factors affecting the outcome of this procedure. A retrospective review was conducted in 25 patients with global root avulsion brachial plexus injuries who underwent ICN transfer. The nerves of the long head of the triceps were the recipient nerves in all patients. The ICNs were used in 2 different ways: 2 ICNs were used as donor nerves in 18 patients, and 3 ICNs were used in 7 patients. The mean follow-up period was 5.6 years. The effective rate of motor recovery in the 25 patients was 56% for the function of the long head of the triceps. There was no significant difference in functional recovery between the patients with 2 or 3 ICN transfers. The outcome of this procedure was not altered if combined with phrenic nerve transfer to the biceps branch. Patients in whom surgery was delayed 6 months or less achieved better results. The transfer of ICNs to the nerve of long head of the triceps is an effective procedure for treating global brachial plexus avulsion injuries, even if combined with phrenic nerve transfer to the biceps branch. Two ICNs appear to be sufficient for donation. The earlier the surgery is performed, the better are the results achieved.

Outcome of partial contralateral C7 nerve transfer–Results of 46 patients

: Partial contralateral C7 transfer has been widely used, but outcomes are significantly different. Therefore, the effects of this procedure need to be evaluated. : To evaluate the outcome of patients treated with partial contralateral C7 transfer and to determine the factors affecting the outcome of this procedure. METHODS;: A retrospective review of 46 patients with global root avulsion brachial plexus injuries who underwent contralateral C7 transfer was conducted. All surgeries were performed by two stages and median nerve was the recipient nerve. The contralateral C7 nerve was used in three different ways. The whole C7 root was used in 8 patients; the posterior division together with the lateral part of the anterior division was used in 14 patients; and the anterior or the posterior division alone was used in 24 patients. The mean follow-up period was 6.4 years. : The effective rate of these 46 patients was 47.83% in motor and 56.52% in sensory function. The patients with whole C7 root transfer obtained significantly better recovery than the patients with partial C7 transfer. The best functional recovery was seen if the interval between the two stages was 4 to 8 months. : Partial contralateral C7 transfer is an effective procedure in treating global brachial plexus avulsion injury. Using the whole C7 root transfer can obtain better recovery and we emphasize using the whole root as the donor. The optimal interval between the two surgery stages is 4 to 8 months.

Electromyographic comparison of various exercises to improve elbow flexion following intercostal nerve transfer

We compared the quantitative electromyographic activity of the elbow flexors during four exercises (forced inspiration, forced expiration, trunk flexion and attempted elbow flexion), following intercostal nerve transfer to the musculocutaneous nerve in 32 patients who had sustained root avulsion brachial plexus injuries. Quantitative electromyographic evaluation of the mean and maximum amplitude was repeated three times for each exercise. We found that mean and maximum elbow flexor activity was highest during trunk flexion, followed by attempted elbow flexion, forced inspiration and finally forced expiration. The difference between each group was significant (p < 0.001), with the exception of the difference between trunk flexion and attempted elbow flexion. Consequently, we recommend trunk flexion exercises to aid rehabilitation following intercostal nerve transfer.

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.

Spinal accessory neurotization for restoration of elbow flexion in avulsion injuries of the brachial plexus

Traumatic root avulsion brachial plexus injuries in 216 patients were treated with spinal accessory-musculocutaneous neurotization to restore elbow flexion. The average postoperative follow-up period was 6 years, with a minimum of 2 years for all patients. The percentage of satisfactory biceps recovery (MRC III or better) was 72.5%. The average interval between the operation and MRC III motor recovery was 17 months. The percentage of poor results increased from 25.5% to 62.5% in patients who underwent operation later than 9 months after injury. This method of neurotization produces a result comparable with, if not better than, the results of other types of neurotization in restoration of elbow flexion.

Direct nerve crossing with the intercostal nerve to treat avulsion injuries of the brachial plexus

One hundred seventy-nine patients with root avulsion brachial plexus injuries were treated with direct nerve crossing with the intercostal nerve and 159 cases were followed more than 1 1/2 years after the operation. When suture was done to the musculocutaneous nerve, 90% of 10 children who had operation within 7 months of injury and 81.8% of 110 adults, younger than 40 years with operation within 6 months of injury regained grade 3 or 4 elbow flexion power. This direct method seems to produce better results than those of nerve crossing, which uses intermediary nerve grafts.