Complications of intercostal nerve transfer for brachial plexus reconstruction

Safety and efficacy of outpatient versus inpatient adult brachial plexus surgery

Purpose

Outpatient orthopedic surgery is becoming more common as a method of providing safe and cost-effective medical care. The purpose of this study was to compare outcomes between adult patients undergoing outpatient versus inpatient brachial plexus surgery.

Methods

A single institution database was queried for patients with brachial plexus injuries undergoing brachial plexus exploration with or without concomitant reconstructive procedures from 2010 to 2022. Outcome measures included 90-day major and minor complications, as well as longer term pain scores and reoperation rates. Multivariate analysis was performed to compare outcomes between the cohorts.

Results

In a group of 51 adult patients, 36 (70.6 %) were admitted for at least one night following surgery and 15 (29.4 %) underwent outpatient surgery. The cohorts were similar with respect to demographics. When compared to brachial plexus procedures performed between 2010 and 2016, those performed between 2017 and 2022 were 67 % more likely to be outpatient (OR 0.33; p = 0.11). The overall major complication rate during the 90-day episode of care was 11.8 % (n = 6), all of which occurred in the inpatient cohort. There was no significant difference in minor complication rate. 90-day reoperation rate due to complications was 2.8 % in the inpatient cohort and 0.0 % in the outpatient cohort.

Conclusion

No prior study has assessed the safety of brachial plexus exploration and reconstruction in an outpatient setting. This study demonstrates that outpatient brachial plexus surgery is a safe option for properly selected patients. Procedures were more often performed outpatient in recent years, reflecting a continuing evolution of our practice.

Proximal and Distal Nerve Transfers in the Management of Brachial Plexus Injuries

Nerve transfer surgery utilizes the redundant and synergistic innervation of intact muscle groups to rehabilitate motor function. This is achieved by transferring functional nerves or fascicles to damaged nerves near the target area, thereby reducing the reinnervation distance and time. The techniques encompass both proximal and distal nerve transfers, customized according to the specific injury. Successful nerve transfer hinges on accurate diagnosis, innovative surgical approaches, and the judicious choice of donor nerves to maximize functional restoration. This study explores nerve transfer strategies and their integration with other procedures, emphasizing their importance in enhancing outcomes in brachial plexus injury management.

The Outcome of Spinal Accessory Nerve Transfer to the Musculocutaneous Nerve in Birth Brachial Plexus Palsy

PURPOSE

Patients with brachial plexus birth injury with limited intraplexal donors require the use of extraplexal donors. Concern regarding the potential for respiratory problems resulting from the harvest of intercostal nerves or the phrenic nerve suggests the need for other options. Transfer of the spinal accessory nerve (SAN) is one option for restoring elbow flexion in adult patients; however, there are few reports of the results of this transfer in brachial plexus birth injury. This study aimed to report the result of SAN transfer to the musculocutaneous nerve (MCN) in brachial plexus birth injury.

METHODS

Patients who had undergone SAN to MCN nerve transfer were included in this study. Patients were classified according to Narakas classification. The chart was reviewed for the time for recovery of elbow flexion according to the Active Movement Scale (AMS).

RESULTS

Eleven patients underwent SAN to MCN transfers with interpositional sural nerve grafts. Mean birthweight was 4,070 grams (range: 3,300-4,670). Mean time to operation was 6.5 months (range: 4-10). Of the 11 patients, two were of Narakas type 3, whereas the others were of type 4. One patient did not recover elbow flexion and underwent later tendon transfer, whereas the other 10 patients reached AMS grade M6 recovery. The median time for AMS grade M1 elbow flexion recovery was eight months (interquartile range: 6.2-8.8) and for AMS grade M5 was 26 months (interquartile range: 14.2-36.5).

CONCLUSIONS

Spinal accessory nerve to MCN transfer with an interposition nerve graft is a viable option for restoring elbow flexion. However, long-term outcomes of this procedure have yet to be fully demonstrated.

TYPE OF STUDY/LEVEL OF EVIDENCE

Case series IV.

The association between number of intercostal nerves transferred and elbow flexion: a systematic review and pooled analysis

OBJECTIVE

This pooled analysis evaluates the association between the number of nerves transferred and postoperative outcomes after intercostal nerve (ICN) nerve transfer for elbow flexion.

METHODS

A systematic and pooled analysis of studies reporting individual patient demographics and outcomes after ICN-musculocutaneous nerve (MCN) transfer for traumatic brachial plexus injury was conducted. The primary outcome was the ability to attain an elbow flexion Medical Research Council (MRC) score of ≥4 at the final postoperative follow-up visit.

RESULTS

Ten studies were included for a total of 128 patients. There were 43 patients who underwent two ICNT, 77 patients who underwent three ICNT, and 8 patients who underwent four ICNT. The three groups did not differ in ability to achieve MRC ≥ 4 (2ICNT 48.8%, 3ICNT 42.9%, 4ICNT 50.0%, p = 0.789). The number of ICNs transferred was not associated with MRC scores ≥4 on the multivariable analysis (OR: 0.55, p = 0.126).

CONCLUSIONS

These results indicate that two ICN transfers may be as effective as three ICN and four ICN transfers and highlight the potential for nonsurgical factors to influence postoperative outcomes. Taken together, this pooled analysis leads us to question the utility of transferring >2 ICNs for MCN neurotization.

Intercostal Nerve Transfer for Biceps Reinnervation in Obstetrical Brachial Plexus Palsy: A Preferred Reporting Items for Systematic Reviews and Meta-Analysis for Individual Patient Data Systematic Review using Individualized Fusion and Comparison to Supraclavicular Exploration and Nerve Grafting

Introduction

The objective of this study was to search existing literature on nerve reconstruction surgery in patients with obstetric brachial plexus palsy to determine whether treatment with supraclavicular exploration and nerve grafting produced better elbow flexion outcomes compared to intercostal nerve transfer.

Methods

This study was a systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis for Individual Patient Data guidelines. A systematic search was conducted using multiple databases. An ordinal regression model was used to analyze the effect of using supraclavicular exploration and nerve grafting or intercostal nerve on elbow flexion with the two scores measured: elbow flexion Medical Research Council scores and Toronto active movements scale scores for elbow flexion.

Results

A final patient database from 6 published articles consisted of 83 supraclavicular exploration and nerve grafting patients (73 patients with Medical Research Council and 10 patients with Toronto score) and 7 published articles which consisted of 131 intercostal nerve patients (84 patients with Medical Research Council and 47 patients with Toronto scores). Patients who underwent supraclavicular exploration and nerve grafting presented with an average Medical Research Council score of 3.9 ± 0.72 and an average Toronto score of 6.2 ± 2.2. Patients who underwent intercostal nerve transfer presented with an average Medical Research Council score of 3.9 ± 0.71 and an average Toronto score of 6.4 ± 1.2. There was no statistical difference between supraclavicular exploration and nerve grafting and intercostal nerve transfer when utilizing Medical Research Council elbow flexion scores (ordinal regression: 0.3821, standard error: 0.4590, p = 0.2551) or Toronto Active Movement Scale score for elbow flexion (ordinal regression: 0.7154, standard error: 0.8487, p = 0.2188).

Conclusion

Regardless of surgical intervention utilized (supraclavicular exploration and nerve grafting or intercostal nerve transfers), patients had excellent outcomes for elbow flexion following obstetric brachial plexus palsy when utilizing Medical Research Council or Toronto scores for elbow flexion. The difference between these scores was not statistically significant.

Type of study/Level of evidence

Therapeutic Study: Investigating the Result of Treatment/level III.

Intercostal Nerve Transfers to Native Triceps or Free Muscle Flaps for Elbow Extension in Brachial Plexus Injuries

Intercostal nerve donors for traumatic brachial plexus injury reconstruction have been used to neurotize native muscles or free-functioning muscle transfers, with inconsistent outcomes reported. The aim was to record a substantial series, evaluate functional outcomes, and identify prognostic factors. We present a single-surgeon case series of 21 consecutive patients who underwent 21 transfer procedures to either native muscles or free-functioning muscles to reconstruct elbow extension over a 9-year period. Outcome parameters included target muscle power grade and timing of recovery. A Medical Research Council power grade ≥ M4 was achieved in 17 reconstructions. The free-functioning muscle group had significantly higher success rate and reached their best power grade 14 months earlier. Free-functioning muscle reconstruction with intercostal nerve transfer is a more complex procedure but has quicker functional recovery and greater reliability in achieving grade M4.

Traumatic brachial plexus injury: diagnosis and treatment

PURPOSE OF THE REVIEW

Traumatic brachial plexus injuries (BPI) are devastating life-altering events, with pervasive detrimental effects on a patient's physical, psychosocial, mental, and financial well-being. This review provides an understanding of the clinical evaluation, surgical indications, and available reconstructive options to allow for the best possible functional outcomes for patients with BPI.

RECENT FINDINGS

The successful management of patients with BPI requires a multidisciplinary team approach including peripheral nerve surgeons, neurology, hand therapy, physical therapy, pain management, social work, and mental health. The initial diagnosis includes a detailed history, comprehensive physical examination, and critical review of imaging and electrodiagnostic studies. Surgical reconstruction depends on the timing of presentation and specific injury pattern. A full spectrum of techniques including neurolysis, nerve grafting, nerve transfers, free functional muscle transfers, tendon transfers, and joint arthrodesis are utilized.

SUMMARY

Despite the devastating nature of BPI injuries, comprehensive care within a multidisciplinary team, open and practical discussions with patients about realistic expectations, and thoughtful reconstructive planning can provide patients with meaningful recovery.

A multidisciplinary approach to the management of brachial plexus injuries: experience from the Mayo Clinic over 100 years

A multidisciplinary brachial plexus clinic has been a relatively new concept, offering different surgical speciality perspectives on the treatment of brachial plexus injuries. The resulting collaborative effort has proven to be greater than the sum of its parts. In this review, the history, philosophy of care, development/implementation and impact of a creation of a multidisciplinary brachial plexus team at the Mayo Clinic are detailed.

The Intercostal Nerves Transfer to the Radial Nerve Branch to the Long Head Triceps Muscle: Influencing Factor and Outcome of 55 Cases

PURPOSE

The objective of this study was to report the functional outcomes and factors affecting the result of intercostal nerves transfer to the radial nerve branch to the long head triceps muscle for restoration of elbow extension in patients with total brachial plexus palsy or C5 to C7 palsy with the loss of triceps muscle function.

METHODS

Fifty-five patients with total brachial plexus palsy or C5 to C7 palsy with no triceps muscle function had a reconstruction of elbow extension by transferring the third to fifth intercostal nerves to the radial nerve branch to the long head triceps muscle. The functional outcomes determined by the Medical Research Council grading were evaluated. Factors influencing the outcomes were determined using logistic regression analysis.

RESULTS

At the follow-up of at least 2 years, 36 patients (65%) had antigravity motor function (Medical Research Council grade, ≥3). Multivariable logistic regression analysis showed that the body mass index, time to surgery, and injury of the dominant limb were associated with the outcome.

CONCLUSIONS

The third to fifth intercostal nerves transfer to the radial nerve branch to the long head triceps muscle is an effective procedure to restore elbow extension. We would recommend using 3 intercostal nerves without grafts; in cases of nerve root avulsion in which there is no chance of spontaneous recovery, early surgery should be considered.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Possible donor nerves for axillary nerve reconstruction in dual neurotization for restoring shoulder abduction in brachial plexus injuries: a systematic review and meta-analysis

Restoring shoulder abduction is one of the main priorities in the surgical treatment of brachial plexus injuries. Double nerve transfer to the axillary nerve and suprascapular nerve is widely used and considered the best option. The most common donor nerve for the suprascapular nerve is the spinal accessory nerve. However, donor nerves for axillary nerve reconstructions vary and it is still unclear which donor nerve has the best outcome. The aim of this study was to perform a systematic review on reconstructions of suprascapular and axillary nerves and to perform a meta-analysis investigating the outcomes of different donor nerves on axillary nerve reconstructions. We conducted a systematic search of English literature from March 2001 to December 2020 following PRISMA guidelines. Two outcomes were assessed, abduction strength using the Medical Research Council (MRC) scale and range of motion (ROM). Twenty-two studies describing the use of donor nerves met the inclusion criteria for the systematic review. Donor nerves investigated included the radial nerve, intercostal nerves, medial pectoral nerve, ulnar nerve fascicle, median nerve fascicle and the lower subscapular nerve. Fifteen studies that investigated the radial and intercostal nerves met the inclusion criteria for a meta-analysis. We found no statistically significant difference between either of these nerves in the abduction strength according to MRC score (radial nerve 3.66 ± 1.02 vs intercostal nerves 3.48 ± 0.64, p = 0.086). However, the difference in ROM was statistically significant (radial nerve 106.33 ± 39.01 vs. intercostal nerve 80.42 ± 24.9, p < 0.001). Our findings support using a branch of the radial nerve for the triceps muscle as a donor for axillary nerve reconstruction when possible. Intercostal nerves can be used in cases of total brachial plexus injury or involvement of the C7 root or posterior fascicle. Other promising methods need to be studied more thoroughly in order to validate and compare their results with the more commonly used methods.

Robotic-Assisted Peripheral Nerve Surgery: A Systematic Review

BACKGROUND

 Robotic-assisted techniques are a tremendous revolution in modern surgery, and the advantages and indications were well discussed in different specialties. However, the use of robotic technique in plastic and reconstructive surgery is still very limited, especially in the field of peripheral nerve reconstruction. This study aims to identify current clinical applications for peripheral nerve reconstruction, and to evaluate the advantages and disadvantages to establish potential uses in the future.

METHODS

 A review was conducted in the literatures from PubMed focusing on currently published robotic peripheral nerve intervention techniques. Eligible studies included related animal model, cadaveric and human studies. Reviews on robotic microsurgical technique unrelated to peripheral nerve intervention and non-English articles were excluded. The differences of wound assessment and nerve management between robotic-assisted and conventional approach were compared.

RESULTS

 Total 19 studies including preclinical experimental researches and clinical reports were listed and classified into brachial plexus reconstruction, peripheral nerve tumors management, peripheral nerve decompression or repair, peripheral nerve harvesting, and sympathetic trunk reconstruction. There were three animal studies, four cadaveric studies, eight clinical series, and four studies demonstrating clinical, animal, or cadaveric studies simultaneously. In total 53 clinical cases, only 20 (37.7%) cases were successfully approached with minimal invasive and intervened robotically; 17 (32.1%) cases underwent conventional approach and the nerves were intervened robotically; 12 (22.6%) cases converted to open approach but still intervened the nerve by robot; and 4 (7.5%) cases failed to approach robotically and converted to open surgery entirely.

CONCLUSION

 Robotic-assisted surgery is still in the early stage in peripheral nerve surgery. We believe the use of the robotic system in this field will develop to become popular in the future, especially in the fields that need cooperation with other specialties to provide the solutions for challenging circumstances.

Robot-assisted Intercostal Nerve Harvesting: A Technical Note about the First Case in Japan

Recently, surgical robotic systems have been used to perform microsurgery. Surgical robots have certain properties that make them well suited to microsurgery; for example, they possess 3-dimensional vision, which can be magnified up to 25 times; their movements are up to 5 times more precise than those of surgeons; they possess 7 degrees of wrist articulation; they do not suffer from physiologic tremors; and they can achieve ergonomic surgical positions. The purpose of this study was to report the feasibility of robot-assisted intercostal nerve harvesting in a clinical case. A healthy 57-year-old man suffered a left plexus injury. On diagnosis of clavicular brachial plexus injury, the intercostal nerve transfer to the muscular cutaneous nerve to restore elbow flexion was performed with Da Vinci Xi robot. The harvesting of intercostal nerves using the conventional open approach involves significant surgical exposure, which can lead to perioperative complications. Robot-assisted intercostal nerve harvesting might reduce postoperative pain, shorten patients’ hospital stays, lower complication rates, and produce better quality-of-life outcomes. There are many issues to be solved when performing robotic surgery on peripheral nerves in Japan. However, robot-assisted intercostal nerve harvesting was a feasible surgical procedure, and patient satisfaction was high.

Intercostal to musculocutaneous nerve transfer in patients with complete traumatic brachial plexus injuries: case series

BACKGROUND

To recover biceps strength in patients with complete brachial plexus injuries, the intercostal nerve can be transferred to the musculocutaneous nerve. The surgical results are very controversial, and most of the studies with good outcomes and large samples were carried out in Asiatic countries. The objective of the study was to evaluate biceps strength after intercostal nerve transfer in patients undergoing this procedure in a Western country hospital.

METHODS

We retrospectively analyzed 39 patients from 2011 to 2016 with traumatic brachial plexus injuries receiving intercostal to musculocutaneous nerve transfer in a rehabilitation hospital. The biceps strength was graded using the British Medical Research Council (BMRC) scale. The variables reported and analyzed were age, the time between trauma and surgery, surgeon experience, body mass index, nerve receptor (biceps motor branch or musculocutaneous nerve), and the number of intercostal nerves transferred. Statistical tests, with a significance level of 5%, were used.

RESULTS

Biceps strength recovery was graded ≥M3 in 19 patients (48.8%) and M4 in 15 patients (38.5%). There was no statistical association between biceps strength and the variables. The most frequent complication was a pleural rupture.

CONCLUSIONS

Intercostal to musculocutaneous nerve transfer is a safe procedure. Still, biceps strength after surgery was ≥M3 in only 48.8% of the patients. Other donor nerve options should be considered, e.g., the phrenic or spinal accessory nerves.

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.

Free Reverse Gracilis Muscle Combined With Steindler Flexorplasty for Elbow Flexion Reconstruction After Failed Primary Repair of Extended Upper-Type Paralysis of the Brachial Plexus

PURPOSE

To report the clinical outcomes of elbow flexion reconstruction using a reverse free gracilis muscle flap plus Steindler flexorplasty in patients with previously failed reconstruction of extended upper-type brachial plexus paralysis.

METHODS

Twenty-four male patients were reoperated upon an average of 45 months (SD, ± 45 months) after brachial plexus repair. The gracilis tendon was secured to the acromion, and the muscle belly was sutured to the biceps distal tendon. Vascular repair was performed preferentially end to end to the radial artery and cephalic vein. Nerve repair was achieved by coapting the nerve to the gracilis to motor fascicles of the median or ulnar nerve. The medial epicondyle was osteotomized, proximally advanced by 4 to 5 cm and secured to the anterior side of the humerus.

RESULTS

Active elbow flexion was restored in 23 of 24 patients. Sixteen patients ultimately achieved M4 strength, among whom 6 had full range of motion (ROM), and the remaining 10 recovered an average of 110° (95% confidence interval [95% CI], 100°-120°) of elbow flexion. Seven patients exhibited M3 elbow flexion strength recovery, which was associated with weaker hands and incomplete ROM, averaging 94° (95% CI, 86°-102°). There was, on average, a 10° (95% CI, 4.4°-15.6°). elbow flexion contracture. Among the 16 patients with M4 level recovery of elbow flexion, supination was partially restored in 12.

CONCLUSIONS

In patients previously operated upon, using a reversed free gracilis muscle flap in association with a Steindler procedure is effective as salvage surgery to restore elbow flexion and partial supination.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Investigation Into the Optimal Number of Intercostal Nerve Transfers for Musculocutaneous Nerve Reinnervation: A Systematic Review

BACKGROUND

The purpose of this study was to systematically review outcomes following intercostal nerve (ICN) transfer for restoration of elbow flexion, with a focus on identifying the optimal number of nerve transfers.

METHODS

A systematic review was performed following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines to identify studies describing ICN transfers to the musculocutaneous nerve (MCN) for traumatic brachial plexus injuries in patients 16 years or older. Demographics were recorded, including age, time to operation, and level of brachial plexus injury. Muscle strength was scored based upon the British Medical Research Council scale.

RESULTS

Twelve studies met inclusion criteria for a total of 196 patients. Either 2 (n = 113), 3 (n = 69), or 4 (n = 11) ICNs were transferred to the MCN in each patient. The groups were similar with regard to patient demographics. Elbow flexion ≥M3 was achieved in 71.3% (95% confidence interval [CI], 61.1%-79.7%) of patients with 2 ICNs, 67.7% (95% CI, 55.3%-78.0%) of patients with 3 ICNs, and 77.0% (95% CI, 44.9%-93.2%) of patients with 4 ICNs ( P = .79). Elbow flexion ≥M4 was achieved in 51.1% (95% CI, 37.4%-64.6%) of patients with 2 ICNs, 42.1% (95% CI, 29.5%-55.9%) of patients with 3 ICNs, and 48.4% (95% CI, 19.2%-78.8%) of patients with 4 ICNs ( P = .66).

CONCLUSIONS

Previous reports have described 2.5 times increased morbidity with each additional ICN harvest. Based on the equivalent strength of elbow flexion irrespective of the number of nerves transferred, 2 ICNs are recommended to the MCN to avoid further donor-site morbidity.

Comparable functional motor outcomes after repair of peripheral nerve injury with an elastase-processed allograft in a rat sciatic nerve model

BACKGROUND

A bridging nerve autograft is the gold standard for the repair of segmental nerve injury that cannot be repaired directly. However, limited availability and donor site morbidity remain major disadvantages of autografts. Here, a nerve allograft decellularized with elastase was compared with an autograft regarding functional motor outcome in a rat sciatic segmental nerve defect model. Furthermore, the effect of storage on this allograft was studied.

METHODS

Sixty-six Lewis rats (250-300 g) underwent a 10-mm sciatic nerve reconstruction using either a cold- (n = 22) or frozen-stored (n = 22) decellularized nerve allograft or an autograft (n = 22). Sprague-Dawley rats (300-350 g) served as full major histocompatibility complex-mismatched donors. Functional motor outcome was evaluated after 12 and 16 weeks. Ankle angle, compound muscle action potential (CMAP), isometric tetanic force, wet muscle weight, and histomorphometry were tested bilaterally.

RESULTS

For CMAP and isometric tetanic force, no significant differences were observed between groups. In contrast, for ankle angle, histomorphometry and muscle weight, the cold-stored allograft performed comparable to the autograft, while the frozen-stored allograft performed significantly inferior to the autograft. At week 16, ankle angle was 88.0 ± 3.1% in the cold-stored group, 77.4 ± 3.6% in the frozen-stored group, and 74.1 ± 3.1% in the autograft group (P < .001); At week 16, the muscle weight showed a recovery up to 71.1 ± 4.8% in the autograft group, 67.0 ± 6.6% in the cold-stored group, and 64.7 ± 3.7% in the frozen-stored group (P < .05).

CONCLUSIONS

A nerve allograft decellularized with elastase, if stored under the right conditions, results in comparable functional motor outcomes as the gold standard, the autograft.

A novel extradural nerve transfer technique by coaptation of C4 to C5 and C7 to C6 for treating isolated upper trunk avulsion of the brachial plexus

The study aimed to demonstrate the feasibility of an extradural nerve anastomosis technique for the restoration of a C5 and C6 avulsion of the brachial plexus. Nine fresh frozen human cadavers were used. The diameters, sizes, and locations of the extradural spinal nerve roots were observed. The lengths of the extradural spinal nerve roots and the distance between the neighboring nerve root outlets were measured and compared in the cervical segments. In the spinal canal, the ventral and dorsal roots were separated by the dura and arachnoid. The ventral and dorsal roots of C7 had sufficient lengths to anastomose those of C6. The ventral and dorsal of C4 had enough length to be transferred to those of C5, respectively. The feasibility of this extradural nerve anastomosis technique for restoring C5 and C6 avulsion of the brachial plexus in human cadavers was demonstrated in our anatomical study.

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

PURPOSE

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.

METHODS

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).

RESULTS

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.

CONCLUSIONS

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.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Electromyographic Findings in Gracilis Muscle Grafts Used to Augment Elbow Flexion in Traumatic Brachial Plexopathy

BACKGROUND

Gracilis muscle graft transplantation is one of the last resort surgical options to restore elbow flexion in patients with chronic traumatic upper-trunk brachial plexopathies.

METHODS

We retrospectively identified 34 patients who underwent surgeries between 1997 and 2014, and had postoperative follow-up for at least 12 months. Demographic, clinical, and electromyographic preoperative and postoperative data were analyzed.

RESULTS

The median age of injury was 30 years old. Most subjects had a complete loss of elbow flexion preoperatively (n = 28, 82.4%). Median time from injury to surgery was 20 months (range = 3-226 months). It did not correlate with the time to reinnervation on EMG (r = 0.35, 95% CI = 0.007-0.62) or with the time improvement in muscle strength (r = 0.35, 95% CI = 0.007-0.62). The mean postoperative follow-up interval was 22.35 months. During that period, 32 of 34 (94%) patients achieved reinnervation. Median times from surgery to graft innervation and to any improvement in elbow flexor muscle power were the same (8.5 months) with overlapping time to event curves.

CONCLUSION

Despite the long-standing and complete loss of elbow flexion in most of our patients, gracilis transfer surgeries have helped most of them to achieve reinnervation and start to regain function. Electromyography is a helpful tool, which along with the clinical examination, can predict postoperative improvement.

Rehabilitation, Using Guided Cerebral Plasticity, of a Brachial Plexus Injury Treated with Intercostal and Phrenic Nerve Transfers

Recovery after surgical reconstruction of a brachial plexus injury using nerve grafting and nerve transfer procedures is a function of peripheral nerve regeneration and cerebral reorganization. A 15-year-old boy, with traumatic avulsion of nerve roots C5–C7 and a non-rupture of C8–T1, was operated 3 weeks after the injury with nerve transfers: (a) terminal part of the accessory nerve to the suprascapular nerve, (b) the second and third intercostal nerves to the axillary nerve, and (c) the fourth to sixth intercostal nerves to the musculocutaneous nerve. A second operation—free contralateral gracilis muscle transfer directly innervated by the phrenic nerve—was done after 2 years due to insufficient recovery of the biceps muscle function. One year later, electromyography showed activation of the biceps muscle essentially with coughing through the intercostal nerves, and of the transferred gracilis muscle by deep breathing through the phrenic nerve. Voluntary flexion of the elbow elicited clear activity in the biceps/gracilis muscles with decreasing activity in intercostal muscles distal to the transferred intercostal nerves (i.e., corresponding to eighth intercostal), indicating cerebral plasticity, where neural control of elbow flexion is gradually separated from control of breathing. To restore voluntary elbow function after nerve transfers, the rehabilitation of patients operated with intercostal nerve transfers should concentrate on transferring coughing function, while patients with phrenic nerve transfers should focus on transferring deep breathing function.

Free Flap Functional Muscle Transfers

Free functional muscle transfers remain a powerful reconstructive tool to restore upper extremity function when other options such as tendon or nerve transfers are not available. This reconstructive technique is commonly used for patients following trauma, ischemic contractures, and brachial plexopathies. Variable outcomes have been reported following free functional muscle transfers that are related to motor nerve availability and reinnervation. This article highlights considerations around donor motor nerve selection, dissection, and use of the gracilis muscle, and the surgical approach to performing a free functional muscle transfer to restore elbow flexion and/or digit flexion.

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.

Robotic intercostal nerve harvest: a feasibility study in a pig model

The aim of this study was to report the feasibility of robotic intercostal nerve harvest in a pig model. A surgical robot, the da Vinci Model S system, was installed after the creation of 3 ports in the pig's left chest. The posterior edges of the fourth, fifth, and sixth intercostal nerves were isolated at the level of the anterior axillary line. The anterior edges of the nerves were transected at the rib cartilage zone. Three intercostal nerve harvesting procedures, requiring an average of 33 minutes, were successfully performed in 3 pigs without major complications. The advantages of robotic microsurgery for intercostal nerve harvest include elimination of physiological tremor, free movement of joint-equipped robotic arms, and amplification of the surgeon's hand motion by as much as 5 times. Robot-assisted neurolysis may be clinically useful for intercostal nerve harvest for brachial plexus reconstruction.

Comparative study of phrenic and intercostal nerve transfers for elbow flexion after global brachial plexus injury

BACKGROUND

Global brachial plexus injuries (BPIs) are devastating events frequently resulting in severe functional impairment. The widely used nerve transfer sources for elbow flexion in patients with global BPIs include intercostal and phrenic nerves.

OBJECTIVE

The aim of this study was to compare phrenic and intercostal nerve transfers for elbow flexion after global BPI.

METHODS

A retrospective review of 33 patients treated with phrenic and intercostal nerve transfer for elbow flexion in posttraumatic global root avulsion BPI was carried out. In the phrenic nerve transfer group, the phrenic nerve was transferred to the anterolateral bundle of the anterior division of the upper trunk (23 patients); in the intercostal nerve transfer group, three intercostal nerves were coapted to the anterolateral bundles of the 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 postoperatively.

RESULTS

The efficiency of motor function in the phrenic nerve transfer group was 83%, while it was 70% in the intercostal nerve transfer group. The two groups were not statistically different in terms of the MRC grade (p=0.646) and EMG results (p=0.646). The outstanding rates of angle of elbow flexion were 48% and 40% in the phrenic and intercostal nerve transfer groups, respectively. There was no significant difference of outstanding rates in the angle of elbow flexion between the two 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 two groups according to MRC grading, angle of elbow flexion, and EMG.

Peripheral nerve injuries: advancing the field through research, collaboration, and education

The Andrew J. Weiland Medal is presented each year by the American Society for Surgery of the Hand and the American Foundation for Surgery of the Hand for a body of work related to hand surgery research. This essay, awarded the Weiland Medal in 2013, focuses on advancing the field of peripheral nerve injuries through research, collaboration, and education.

[Complications in brachial plexus surgery]

OBJECTIVE

Although traumatic brachial plexus injuries are relatively rare in trauma patients, their effects on the functionality of the upper limb can be very disabling. The authors' objective was to assess the complications in a series of patients operated for brachial plexus injuries.

MATERIAL AND METHOD

This was a retrospective evaluation of patients operated on by the authors between August 2009 and March 2013.

RESULTS

We performed 36 surgeries on 33 patients. The incidence of complications was 27.7%. Of these, only 1 (2.7%) was considered serious and associated with the procedure (iatrogenic injury of brachial artery). There was another serious complication (hypoxia in patients with airway injury) but it was not directly related to the surgical procedure. All other complications were considered minor (wound dehiscence, hematoma, infection). There was no mortality in our series.

CONCLUSIONS

The complications in our series are similar to those reported in the literature. Serious complications (vascular, neural) are rare and represent less than 5% in all the different series. Given the rate of surgical complications and the poor functional perspective for a brachial plexus injury without surgery, we believe that surgery should be the treatment of choice.

Free function muscle transfers for upper extremity reconstruction: a review of indications, techniques, and outcomes

Free functional muscle transfer (FFMT) replaces destroyed, denervated, or resected skeletal muscle units in the upper extremity with functioning skeletal muscle from other locations in the body. Common indications for FFMT include brachial plexus injuries, ischemic contracture, tumor resection, and extensive direct muscle trauma. Recent studies have focused on improving patient outcomes through refinements in muscle flap harvest and inset, donor nerve selection, and postoperative management. In this review, we assess and summarize the current literature on FFMT, with emphasis on etiopathogenesis, diagnosis, treatment, postoperative management, and clinical outcomes.

Nerve transfers for the upper extremity: new horizons in nerve reconstruction

Nerve transfers are key components of the surgeon's armamentarium in brachial plexus and complex nerve reconstruction. Advantages of nerve transfers are that nerve regeneration distances are shortened, pure motor or sensory nerve fascicles can be selected as donors, and nerve grafts are generally not required. Similar to the principle of tendon transfers, expendable donor nerves are transferred to denervated nerves with the goal of functional recovery. Transfers may be subdivided into intraplexal, extraplexal, and distal types; each has a unique role in the reconstructive process. A thorough diagnostic workup and intraoperative assessment help guide the surgeon in their use. Nerve transfers have made a positive impact on the outcomes of nerve surgery and are essential tools in complex nerve reconstruction.

Imaging and electrodiagnostic work-up of acute adult brachial plexus injuries

Imaging and electrodiagnostic studies form an essential part of the evaluation of the patient with traumatic brachial plexopathy, enabling clarification of surgical options, prognostication of outcome and formulation of postoperative management. The primary objective of imaging is to identify pre-ganglionic injury indicative of nerve root avulsion. The presence of one or more nerve root avulsion injuries is a critical factor in surgical decision-making and the prognosis of surgical reconstruction. CT myelography is the current imaging modality of choice for this purpose. Initial electrodiagnostic (EDX) testing is ideally performed no sooner than 4 weeks following injury unless otherwise clinically indicated. Follow-up testing can be helpful at approximately 6 week intervals. The sensory nerve amplitudes are the most important component of nerve conduction testing in distinguishing between pre- and post-ganglionic injuries. Electromyographic studies will also assist in the determination of a pre- from post-ganglionic injury, the level of plexus involvement and identify potential donor nerves that may be suitable for use as transfers.