Utility of delayed surgical repair of neonatal brachial plexus palsy

Recovery of Shoulder, Elbow, and Forearm Movement After Nerve Reconstruction for Neonatal Brachial Plexus Palsy

BACKGROUND AND OBJECTIVES

There is a relative dearth of published data with respect to recovery of upper extremity movement after nerve reconstruction for neonatal brachial plexus palsy (NBPP). This study aimed to demonstrate long-term recovery of active range of motion (AROM) at the shoulder, elbow, and forearm after nerve reconstruction for NBPP and to compare that with patients managed nonoperatively.

METHODS

We interrogated a prospectively collected database of all patients evaluated for NBPP at a single institution from 2005 to 2020. AROM measurements for shoulder, elbow, and forearm movements were collected at every visit up to 5 years of follow-up and normalized between 0 and 1. We used generalized estimated equations to predict AROM for each movement within local age windows over 5 years and compared the operative and nonoperative cohorts at each age interval.

RESULTS

In total, >13 000 collected datapoints representing 425 conservatively and 99 operatively managed children were included for analysis. At 5 years, absolute recovery of AROM after nerve reconstruction was ∼50% for shoulder abduction and forward flexion, ∼65% for shoulder external rotation, and ∼75% for elbow flexion and forearm supination, with ∼20% loss of elbow extension AROM. Despite more limited AROM on presentation for the operative cohort, at 5 years, there was no significant difference between the groups in AROM for shoulder external rotation, elbow extension, or forearm supination, and, in Narakas grade 1-2 injury, shoulder abduction and forward flexion.

CONCLUSION

We demonstrate recovery of upper extremity AROM after nerve surgery for NBPP. Despite more severe presenting injury, operative patients had similar recovery of AROM when compared with nonoperative patients for shoulder external rotation, elbow extension, forearm supination, and, for Narakas grade 1-2 injury, shoulder abduction and forward flexion.

Impact of Timing of Primary Nerve Surgery on Shoulder, Forearm, and Elbow Recovery in Neonatal Brachial Plexus Palsy

BACKGROUND AND OBJECTIVES

Neonatal brachial plexus palsy (NBPP) almost universally affects movement at the shoulder, elbow, and forearm. Timing of nerve reconstruction surgery to optimize long-term outcomes remains unknown. This study aimed to determine if timing of nerve reconstruction affects long-term recovery of an active range of motion (AROM) at the shoulder, elbow, and forearm in NBPP.

METHODS

We interrogated a prospectively collected database of all patients with NBPP who underwent primary nerve surgery at a single tertiary referral center between 2005 and 2020. The cohort was divided into those who underwent surgery at ≤6 or >6 months old and ≤9 or >9 months old. AROM for shoulder abduction, forward flexion, and external rotation, elbow flexion and extension, and forearm supination were collected at each visit.

RESULTS

Ninety-nine children were included in the analysis; 28 underwent surgery at ≤6 months old, 71 at >6 months, 74 at ≤9 months, and 25 at >9 months. There was no difference in AROM at 5 years for any of the movements between the ≤6- and >6-month groups. The ≤9-month group had significantly better shoulder forward flexion and elbow extension AROM than the >9-month group at a 5-year follow-up and better forearm supination at up to a 15-year follow-up. Patients who presented earlier were more likely to have earlier operations.

CONCLUSION

Surgery before 9 months may improve long-term upper extremity recovery in NBPP. Early referral should be encouraged to optimize timing of operative intervention.

A Porcine Model of Peripheral Nerve Injury Enabling Ultra-Long Regenerative Distances: Surgical Approach, Recovery Kinetics, and Clinical Relevance

BACKGROUND

Millions of Americans experience residual deficits from traumatic peripheral nerve injury (PNI). Despite advancements in surgical technique, repair typically results in poor functional outcomes due to prolonged periods of denervation resulting from long regenerative distances coupled with slow rates of axonal regeneration. Novel surgical solutions require valid preclinical models that adequately replicate the key challenges of clinical PNI.

OBJECTIVE

To develop a preclinical model of PNI in swine that addresses 2 challenging, clinically relevant PNI scenarios: long segmental defects (≥5 cm) and ultra-long regenerative distances (20-27 cm). Thus, we aim to demonstrate that a porcine model of major PNI is suitable as a potential framework to evaluate novel regenerative strategies prior to clinical deployment.

METHODS

A 5-cm-long common peroneal nerve or deep peroneal nerve injury was repaired using a saphenous nerve or sural nerve autograft, respectively. Histological and electrophysiological assessments were performed at 9 to 12 mo post repair to evaluate nerve regeneration and functional recovery. Relevant anatomy, surgical approach, and functional/histological outcomes were characterized for both repair techniques.

RESULTS

Axons regenerated across the repair zone and were identified in the distal stump. Electrophysiological recordings confirmed these findings and suggested regenerating axons reinnervated target muscles.

CONCLUSION

The models presented herein provide opportunities to investigate peripheral nerve regeneration using different nerves tailored for specific mechanisms of interest, such as nerve modality (motor, sensory, and mixed fiber composition), injury length (short/long gap), and total regenerative distance (proximal/distal injury).

Tissue Engineered Bands of Büngner for Accelerated Motor and Sensory Axonal Outgrowth

Following peripheral nerve injury comprising a segmental defect, the extent of axon regeneration decreases precipitously with increasing gap length. Schwann cells play a key role in driving axon re-growth by forming aligned tubular guidance structures called bands of Büngner, which readily occurs in distal nerve segments as well as within autografts - currently the most reliable clinically-available bridging strategy. However, host Schwann cells generally fail to infiltrate large-gap acellular scaffolds, resulting in markedly inferior outcomes and motivating the development of next-generation bridging strategies capable of fully exploiting the inherent pro-regenerative capability of Schwann cells. We sought to create preformed, implantable Schwann cell-laden microtissue that emulates the anisotropic structure and function of naturally-occurring bands of Büngner. Accordingly, we developed a biofabrication scheme leveraging biomaterial-induced self-assembly of dissociated rat primary Schwann cells into dense, fiber-like three-dimensional bundles of Schwann cells and extracellular matrix within hydrogel micro-columns. This engineered microtissue was found to be biomimetic of morphological and phenotypic features of endogenous bands of Büngner, and also demonstrated 8 and 2× faster rates of axonal extension in vitro from primary rat spinal motor neurons and dorsal root ganglion sensory neurons, respectively, compared to 3D matrix-only controls or planar Schwann cells. To our knowledge, this is the first report of accelerated motor axon outgrowth using aligned Schwann cell constructs. For translational considerations, this microtissue was also fabricated using human gingiva-derived Schwann cells as an easily accessible autologous cell source. These results demonstrate the first tissue engineered bands of Büngner (TE-BoBs) comprised of dense three-dimensional bundles of longitudinally aligned Schwann cells that are readily scalable as implantable grafts to accelerate axon regeneration across long segmental nerve defects.

Cost-Effectiveness Analysis of Combined Dual Motor Nerve Transfers versus Alternative Surgical and Nonsurgical Management Strategies to Restore Shoulder Function Following Upper Brachial Plexus Injury

BACKGROUND

Restoration of shoulder function is an important treatment goal in upper brachial plexus injury (UBPI). Combined dual motor nerve transfer (CDNT) of spinal accessory to suprascapular and radial to axillary nerves demonstrates good functional recovery with minimal risk of perioperative complications.

OBJECTIVE

To evaluate the cost-effectiveness of CDNT vs alternative operative and nonoperative treatments for UBPI.

METHODS

A decision model was constructed to evaluate costs ($, third-party payer) and effectiveness (quality-adjusted life years [QALYs]) of CDNT compared to glenohumeral arthrodesis (GA), conservative management, and nontreatment strategies. Estimates for branch probabilities, costs, and QALYs were derived from published studies. Incremental cost-effectiveness ratios (ICER, $/QALY) were calculated to compare the competing strategies. One-way, 2-way, and probabilistic sensitivity analyses with 100 000 iterations were performed to account for effects of uncertainty in model inputs.

RESULTS

Base case model demonstrated CDNT effectiveness, yielding an expected 21.04 lifetime QALYs, compared to 20.89 QALYs with GA, 19.68 QALYs with conservative management, and 19.15 QALYs with no treatment. The ICERs for CDNT, GA, and conservative management vs nontreatment were $5776.73/QALY, $10 483.52/QALY, and $882.47/QALY, respectively. Adjusting for potential income associated with increased likelihood of returning to work after clinical recovery demonstrated CDNT as the dominant strategy, with ICER = -$56 459.54/QALY relative to nontreatment. Probabilistic sensitivity analysis showed CDNT cost-effectiveness at a willingness-to-pay threshold of $50 000/QALY in 78.47% and 81.97% of trials with and without income adjustment, respectively. Conservative management dominated in <1% of iterations.

CONCLUSION

CDNT and GA are cost-effective interventions to restore shoulder function in patients with UBPI.

Nerve transfer versus muscle transfer to restore elbow flexion after pan-brachial plexus injury: a cost-effectiveness analysis

OBJECTIVE Pan-brachial plexus injury (PBPI), involving C5-T1, disproportionately affects young males, causing lifelong disability and decreased quality of life. The restoration of elbow flexion remains a surgical priority for these patients. Within the first 6 months of injury, transfer of spinal accessory nerve (SAN) fascicles via a sural nerve graft or intercostal nerve (ICN) fascicles to the musculocutaneous nerve can restore elbow flexion. Beyond 1 year, free-functioning muscle transplantation (FFMT) of the gracilis muscle can be used to restore elbow flexion. The authors present the first cost-effectiveness model to directly compare the different treatment strategies available to a patient with PBPI. This model assesses the quality of life impact, surgical costs, and possible income recovered through restoration of elbow flexion. METHODS A Markov model was constructed to simulate a 25-year-old man with PBPI without signs of recovery 4.5 months after injury. The management options available to the patient were SAN transfer, ICN transfer, delayed FFMT, or no treatment. Probabilities of surgical success rates, quality of life measurements, and disability were derived from the published literature. Cost-effectiveness was defined using incremental cost-effectiveness ratios (ICERs) defined by the ratio between costs of a treatment strategy and quality-adjusted life years (QALYs) gained. A strategy was considered cost-effective if it yielded an ICER less than a willingness-to-pay of $50,000/QALY gained. Probabilistic sensitivity analysis (PSA) was performed to address parameter uncertainty. RESULTS The base case model demonstrated a lifetime QALYs of 22.45 in the SAN group, 22.0 in the ICN group, 22.3 in the FFMT group, and 21.3 in the no-treatment group. The lifetime costs of income lost through disability and interventional/rehabilitation costs were $683,400 in the SAN group, $727,400 in the ICN group, $704,900 in the FFMT group, and $783,700 in the no-treatment group. Each of the interventional modalities was able to dramatically improve quality of life and decrease lifelong costs. A Monte Carlo PSA demonstrated that at a willingness-to-pay of $50,000/QALY gained, SAN transfer dominated in 88.5% of iterations, FFMT dominated in 7.5% of iterations, ICN dominated in 3.5% of iterations, and no treatment dominated in 0.5% of iterations. CONCLUSIONS This model demonstrates that nerve transfer surgery and muscle transplantation are cost-effective strategies in the management of PBPI. These reconstructive neurosurgical modalities can improve quality of life and lifelong earnings through decreasing disability.

Analyzing cost-effectiveness of ulnar and median nerve transfers to regain forearm flexion

OBJECTIVE Peripheral nerve transfers to regain elbow flexion via the ulnar nerve (Oberlin nerve transfer) and median nerves are surgical options that benefit patients. Prior studies have assessed the comparative effectiveness of ulnar and median nerve transfers for upper trunk brachial plexus injury, yet no study has examined the cost-effectiveness of this surgery to improve quality-adjusted life years (QALYs). The authors present a cost-effectiveness model of the Oberlin nerve transfer and median nerve transfer to restore elbow flexion in the adult population with upper brachial plexus injury. METHODS Using a Markov model, the authors simulated ulnar and median nerve transfers and conservative measures in terms of neurological recovery and improvements in quality of life (QOL) for patients with upper brachial plexus injury. Transition probabilities were collected from previous studies that assessed the surgical efficacy of ulnar and median nerve transfers, complication rates associated with comparable surgical interventions, and the natural history of conservative measures. Incremental cost-effectiveness ratios (ICERs), defined as cost in dollars per QALY, were calculated. Incremental cost-effectiveness ratios less than $50,000/QALY were considered cost-effective. One-way and 2-way sensitivity analyses were used to assess parameter uncertainty. Probabilistic sampling was used to assess ranges of outcomes across 100,000 trials. RESULTS The authors' base-case model demonstrated that ulnar and median nerve transfers, with an estimated cost of $5066.19, improved effectiveness by 0.79 QALY over a lifetime compared with conservative management. Without modeling the indirect cost due to loss of income over lifetime associated with elbow function loss, surgical treatment had an ICER of $6453.41/QALY gained. Factoring in the loss of income as indirect cost, surgical treatment had an ICER of -$96,755.42/QALY gained, demonstrating an overall lifetime cost savings due to increased probability of returning to work. One-way sensitivity analysis demonstrated that the model was most sensitive to assumptions about cost of surgery, probability of good surgical outcome, and spontaneous recovery of neurological function with conservative treatment. Two-way sensitivity analysis demonstrated that surgical intervention was cost-effective with an ICER of $18,828.06/QALY even with the authors' most conservative parameters with surgical costs at $50,000 and probability of success of 50% when considering the potential income recovered through returning to work. Probabilistic sampling demonstrated that surgical intervention was cost-effective in 76% of cases at a willingness-to-pay threshold of $50,000/QALY gained. CONCLUSIONS The authors' model demonstrates that ulnar and median nerve transfers for upper brachial plexus injury improves QALY in a cost-effective manner.

Functional outcomes of infants with Narakas grade 1 birth-related brachial plexus palsy undergoing neurotization compared with infants who did not require surgery

PURPOSE

This study aimed to investigate the functional outcomes of infants who underwent neurotization for shoulder abduction and elbow flexion in Narakas grade 1 birth-related brachial plexus palsy (BRBPP) and compare this cohort to children who progressed past the point of needing intervention.

METHODS

A cohort study was conducted at a single center between 1999 and 2010. Two-hundred and eight infants were identified with BRBPP that presented for neurosurgical care as infants. Of those, 38 (18 %) received neurosurgical intervention with approximate 2-year follow-up. Only infants undergoing cranial nerve XI to suprascapular nerve neurotization for shoulder abduction (SA) weakness and medial pectoral nerve to musculocutaneous nerve neurotization for elbow flexion (EF) weakness were included. In addition, 30 infants who improved past the need for surgical intervention and had been followed for close to 24 months were identified for comparison. Descriptive statistics and exploratory analysis were performed using SAS 9.2 and JMP 9.0.2.

RESULTS

Shoulder abduction For SA, there were no differences in age at presentation between the operative (6-9 months) and non-operative (5-9 months) groups (p = 0.99). Infants in the operative cohort had significantly worse initial function (p = 0.008). At 2-year follow-up, the two groups had become similar (p = 1.0). Elbow flexion For EF, there were no differences in age at presentation between the operative (6-8 months) and non-operative (5-8.5 months) groups (p = 0.98). Infants in the operative cohort had significantly worse initial function (p = 0.002). At 2-year follow-up, those two groups had become similar (p = 0.26).

CONCLUSIONS

Infants undergoing neurotization for Narakas grade 1 brachial plexus injury had similar long-term function to those who had improved and never required surgery. The preoperative exam findings were significantly different between the intervened and non-intervened groups, while the postoperative exam findings were not.