Rapid recovery of serratus anterior muscle function after microneurolysis of long thoracic nerve injury

Electrical stimulation of human neural stem cells via conductive polymer nerve guides enhances peripheral nerve recovery

Severe peripheral nerve injuries often result in permanent loss of function of the affected limb. Current treatments are limited by their efficacy in supporting nerve regeneration and behavioral recovery. Here we demonstrate that electrical stimulation through conductive nerve guides (CNGs) enhances the efficacy of human neural progenitor cells (hNPCs) in treating a sciatic nerve transection in rats. Electrical stimulation strengthened the therapeutic potential of NPCs by upregulating gene expression of neurotrophic factors which are critical in augmenting synaptic remodeling, nerve regeneration, and myelination. Electrically-stimulated hNPC-containing CNGs are significantly more effective in improving sensory and motor functions starting at 1-2 weeks after treatment than either treatment alone. Electrophysiology and muscle assessment demonstrated successful re-innervation of the affected target muscles in this group. Furthermore, histological analysis highlighted an increased number of regenerated nerve fibers with thicker myelination in electrically-stimulated hNPC-containing CNGs. The elevated expression of tyrosine kinase receptors (Trk) receptors, known to bind to neurotrophic factors, indicated the long-lasting effect from electrical stimulation on nerve regeneration and distal nerve re-innervation. These data suggest that electrically-enhanced stem cell-based therapy provides a regenerative rehabilitative approach to promote peripheral nerve regeneration and functional recovery.

Long-term Improvements of Neuroplasty and Scalene Muscle Resection in LTN-injured Winged Scapula Patients

Injuries to the long thoracic nerve, which directly branches off of the C6, C7, and C8 brachial plexus nerve roots, can cause scapular winging and affect shoulder movements. Long thoracic nerve injuries resulting from accidents, violence, or overuse can be severe lesions requiring challenging surgeries. We evaluated the long-term functional outcomes of neuroplasty and the scalene muscle resection procedures in patients with long thoracic nerve injury and winging scapula.

Methods

All 15 patients who underwent scalene muscle resection with decompression and neurolysis of the long thoracic nerve in a single institution to treat winged scapula and limited shoulder movements between March 2007 and May 2020 with follow-up over 2 years were included in the study.

Results

Shoulder abduction and arm flexion improved significantly to 158 ± 52 degrees and 165 ± 53 degrees from a mean of 108 ± 54 degrees and 104 ± 52 degrees (P < 0.02) over 2 years after surgery (mean 3.4 years). Overall, there was a significant reduction in the scapular winging, as assessed by estimating the decrease in the angle between the scapular plane and the posterior chest wall. The extent of the score greatly improved post-surgically from a mean of 1.2 ± 0.4 to 3.5 ± 0.9 (range 1-4; 1-severe, 2-moderate, 3-mild, and 4-minimal) (P < 0.01).

Conclusion

The improvement in shoulder movements and reduced scapular winging was significant and stable over 2 years of surgery in 81% of our study patients.

Excellent Recovery of Shoulder Movements After Decompression and Neurolysis of Long Thoracic Nerve in Teen Patients With Winging Scapula

Introduction: In teens, athletes, in general, have been found to have shoulder pain and or winging scapula resulting from long thoracic or spinal accessory nerve injuries. Accident (fall) and stretch injuries due to overuse and poor sports techniques mainly cause these injuries that affect their upper extremity movements and functions. Here, we report a significant improvement in scapula winging and shoulder active range of motion in 16 teen patients after long thoracic nerve decompression and neurolysis. Patients and Methods: This was a retrospective study of 16 teen patients who had severe winging scapula and poor shoulder movements and function. Therefore, they underwent decompression and neurolysis of long thoracic nerve with us, between 2005 and 2016. The average patient age was 17 years (range, 14-19 years). These patients had been suffering from paralysis for an average of 15 months (range, 2-48 months). All patients underwent a preoperative electromyographic assessment in addition to clinical evaluation to confirm the long thoracic nerve injury. Results: Scapula winging was severe in 10 of 16 patients (63%), moderate in 2 patients (12%), and mild in 4 patients (25%) in our present study. Mean shoulder abduction (128°) and flexion (138°) were poor preoperatively. Shoulder abduction and flexion improved to 180° in 15 patients (94%) and good (120°) in 1 patient (6%) at least 2 months after surgery. In 11 patients (69%), the winged scapula was completely corrected postsurgically and it was less prominent in other 5 patients. Conclusion: Long thoracic nerve decompression and neurolysis significantly improved scapular winging in all 16 teen patients in our present study, producing "excellent" shoulder movements in 15 patients (94%) and "good" result in 1 patient (6%).

Surgical and Clinical Decision Making in Isolated Long Thoracic Nerve Palsy

BACKGROUND

Isolated long thoracic nerve palsy results in scapular winging and destabilization. In this study, we review the surgical management of isolated long thoracic nerve palsy and suggest a surgical technique and treatment algorithm to simplify management.

METHODS

In total, 19 patients who required surgery for an isolated long thoracic nerve palsy were reviewed retrospectively. Preoperative demographics, electromyography (EMG), and physical examinations were reviewed. Intraoperative nerve stimulation, surgical decision making, and postoperative outcomes were reviewed.

RESULTS

In total, 19 patients with an average age of 32 were included in the study. All patients had an isolated long thoracic nerve palsy caused by either an injury (58%), Parsonage-Turner syndrome (32%), or shoulder surgery (10%); 18 patients (95%) underwent preoperative EMG; 10 with evidence of denervation (56%); and 13 patients had motor unit potentials in the serratus anterior (72%). The preoperative EMG did not correlate with intraoperative nerve stimulation in 13 patients (72%) and did correlate in 5 patients (28%); 3 patients had a nerve transfer (3 thoracodorsal to long thoracic at lateral chest, 1 pec to long thoracic at supraclavicular incision). In the 3 patients who had a nerve transfer, there was return of full forward flexion of the shoulder at an average of 2.5 months.

CONCLUSIONS

A treatment algorithm based on intraoperative nerve stimulation will help guide surgeons in their clinical decision making in patients with isolated long thoracic nerve palsy. Intraoperative nerve stimulation is the gold standard in the management of isolated long thoracic nerve palsy.

Winged Scapula: A Comprehensive Review of Surgical Treatment

Winged scapula is caused by paralysis of the serratus anterior or trapezius muscles due to damage to the long thoracic or accessory nerves, resulting in loss of strength and range of motion of the shoulder. Because this nerve damage can happen in a variety of ways, initial diagnosis may be overlooked. This paper discusses the anatomical structures involved in several variations of winged scapula, the pathogenesis of winged scapula, and several historical and contemporary surgical procedures used to treat this condition. Additionally, this review builds upon the conclusions of several studies in order to suggest areas for continued research regarding the treatment of winged scapula.

Meta-Analysis of Long Thoracic Nerve Decompression and Neurolysis Versus Muscle and Tendon Transfer Operative Treatments of Winging Scapula

Background:

Injury to long thoracic and the spinal accessory nerves can cause winging scapula as a result of weakness and paralysis of the trapezius and serratus anterior muscles. Although these nerve and muscle operations have been reported to correct winging scapula due to various causes, there is no report on comparing the outcomes of these procedures in peer-reviewed Pubmed-indexed literature. In this article, we compared the improvements in the restoration of shoulder functions in winging scapula patients after long thoracic nerve decompression (LTND) in our present study with outcomes of muscle and tendon transfer operations published in the literature (Aetna cited articles).

Methods:

Twenty-five winging scapula patients met the inclusion criteria, who had LTND and neurolysis at our clinic since 2008. Electromyographic evaluation of the brachial plexus and long thoracic nerve distribution was performed preoperatively for all our patients in this study. Operating surgeon (R.K.N.) examined all patients and measured pre- and postoperative range of motion of the affected shoulder. The mean follow-up was 23 months (range, 13–46 months). Age of our patients in this study at the time of surgery was between 13 and 63 years. These patients had winging scapula between 5 days (tennis injury) and several years before surgery and some were unknown.

Results:

Shoulder flexion and abduction improved to an average of 163˚ (P < 0.000006) and 157˚ (P < 0.0000005) from 104˚ and 97˚ at least 1-year post-LTND in 25 winging scapula patients in our present study. This is statistically significant in comparison to the reported improvements resulting from muscle and tendon transfer procedures in the Pubmed-indexed (Aetna cited) literature.

Conclusion:

This meta-analysis suggests that nerve surgeries such as LTND and neurolysis are effective techniques in correcting winging scapula in comparison with muscle transfer operations.

Significant improvement in nerve conduction, arm length, and upper extremity function after intraoperative electrical stimulation, neurolysis, and biceps tendon lengthening in obstetric brachial plexus patients

Background

Progressive loss of extension and concomitant bony deformity of the elbow are results of persistent biceps contracture in obstetric brachial plexus injury (OBPI) patients, if they do not fully recover. This adversely affects the growth and development and functions of the upper extremity.

Patients and method

We have performed biceps tendon lengthening (BTL) using a Z-plasty technique on OBPI patients aged 4 years to adulthood, who had been diagnosed with biceps tendon fixed flexion contractures. Ulnar, radial, and median nerve decompression was also performed at the same sitting. Somatosensory evoked potential (SSEP) monitoring was performed by stimulating the median and ulnar nerves at the wrist and the radial nerve over the dorsum of the hand and recording the peripheral, cervical, and cortical responses.

Seven children with obstetric brachial plexus palsy with an average age of 11 years (8.7–14.2 years) were included in this report. Mean follow-up time was 7.4 months (4–11 months). All the patients in this report had the elbow flexion contractures greater than 30°.

Results

Mean flexion contracture was 35° (30°–45°) preoperatively, which was improved to 0°–10° postoperatively with an average follow-up of 7 (4–11) months. This surgical procedure corrected the elbow flexion contractures, about an average of 25° and an improved length almost to normal, and improved the upper extremity functions. Neurophysiological data showed significant improvement in conduction of all three nerves tested after neurolysis. Further, median and radial nerve amplitude increase was statistically significant.

Conclusion

Statistically significant improvement in biceps length as well as nerve conduction was observed after the surgery. None of the children in our study lost biceps function, although weakness of the biceps is both a short- and long-term risk associated with biceps lengthening.

Isolated paralysis of the serratus anterior muscle: surgical release of the distal segment of the long thoracic nerve in 52 patients

INTRODUCTION

Isolated serratus anterior (SA) paralysis is a rare condition that is secondary to direct trauma or overuse. Patients complain of neuropathic pain and/or muscle pain secondary to overexertion of the other shoulder stabilizing muscles. As the long thoracic nerve (LTN) passes along the thorax, it can be compressed by blood vessels and/or fibrotic tissue. The goal of the current study was to evaluate the outcomes of surgical release of the distal segment of the LTN in cases of isolated SA paralysis.

PATIENTS AND METHODS

This was a retrospective study of 52 consecutive cases operated on between 1997 and 2012. The average patient age was 32 years (range 13-70). Patients had been suffering from paralysis for an average of 2 years (range 4-259 months); the paralysis was complete in 52% of cases. Every patient underwent a preoperative electroneuromyography (ENMG) assessment to confirm that only the SA was affected and there were no signs of re-innervation.

RESULTS

Every patient had abnormal intraoperative findings. There were no complications. All patients showed at least partial improvement following the procedure. The improvement was excellent or good in 45 cases (86.7%), moderate in 4 cases (7.7%) and slight in 3 cases (5.6%). In 32 cases (61.5%), the winged scapula was completely corrected; it was less prominent in 19 cases and was unchanged in one case. The best outcomes following surgical release occurred in patients who presented without preoperative or neuropathic pain and were treated within 18 months of paralysis.

DISCUSSION

Isolated SA paralysis due to mechanical injury resembles entrapment neuropathy. We discovered signs of LTN compression or restriction during surgery. Surgical release of the distal segment of the LTN is a simple, effective treatment for pain that provides complete motor recovery when performed within the first 12 months of the paralysis.

LEVEL OF EVIDENCE

IV.

Scapular Winging

This review explores the causes of scapula winging, with overview of the relevant anatomy, proposed aetiology and treatment. Particular focus is given to lesions of the long thoracic nerve, which is reported to be the most common aetiological factor.

[Winged scapula, a condition for the surgical area?]

The winged scapula secondary to long thoracic nerve injury is an uncommon condition. It is most frequently reported in the literature associated with surgical activities, either due to poor positioning during anesthesia or by an iatrogenic traumatic event during surgical procedures. We expose 3 cases and a brief etiological and literature review, to present the multiple origins of this injury, which are not always related to this area of activity, as these are not the only causes of this injury.

Modified Quad surgery significantly improves the median nerve conduction and functional outcomes in obstetric brachial plexus nerve injury

Background

Nerve conduction studies or somatosensory evoked potentials (SSEPs) have become an important tool in the investigation of peripheral nerve lesions, and is sensitive in detecting brachial plexus nerve injury, and other nerve injuries.

To investigate whether the modified Quad surgical procedure improves nerve conductivity and functional outcomes in obstetric brachial plexus nerve injury (OBPI) patients.

Methods

All nerves were tested with direct functional electrical stimulation. A Prass probe was used to stimulate the nerves, and recording the response, the compound motor action potential (CMAP) in the muscle. SSEP monitoring was performed pre- and post modified Quad surgery, stimulating the median and ulnar nerves at the wrist, the radial nerve over the dorsum of the hand, recording the peripheral, cervical and cortical responses. All patients have had the modified Quad surgery (n = 19). The modified Quad surgery is a muscle release and transfer surgery with nerve decompressions. All patients were assessed preoperatively and postoperatively by evaluating video recordings of standardized movements, the modified Mallet scale to index active shoulder movements.

Results

The cervical responses were significantly lower in amplitude in the affected arm than the un-affected arm. The median nerve conduction was significantly improved from 8.04 to 9.26 (P < 0.022) post-operatively. The shoulder abduction was also significantly improved (pre-op 30° ± 23.3 to 143° ± 33.7, p < 0.0001), with a mean follow-up of 43 months after the modified Quad surgery in these patients.

Conclusion

Median nerve conduction, and shoulder abduction were significantly improved in OBPI children, who have undergone the modified Quad procedure with neuroplasty, internal microneurolysis and tetanic stimulation of the median nerve.

Scapula alata in early breast cancer patients enrolled in a randomized clinical trial of post-surgery short-course image-guided radiotherapy

BACKGROUND

Scapula alata (SA) is a known complication of breast surgery associated with palsy of the serratus anterior, but it is seldom mentioned. We evaluated the risk factors associated with SA and the relationship of SA with ipsilateral shoulder/arm morbidity in a series of patients enrolled in a trial of post-surgery radiotherapy (RT).

METHODS

The trial randomized women with completely resected stage I-II breast cancer to short-course image-guided RT, versus conventional RT. SA, arm volume and shoulder-arm mobility were measured prior to RT and at one to three months post-RT. Shoulder/arm morbidities were computed as a post-RT percentage change relative to pre-RT measurements.

RESULTS

Of 119 evaluable patients, 13 (= 10.9%) had pre-RT SA. Age younger than 50 years old, a body mass index less than 25 kg/m2, and axillary lymph node dissection were significant risk factors, with odds ratios of 4.8 (P = 0.009), 6.1 (P = 0.016), and 6.1 (P = 0.005), respectively. Randomization group was not significant. At one to three months' post-RT, mean arm volume increased by 4.1% (P = 0.036) and abduction decreased by 8.6% (P = 0.046) among SA patients, but not among non-SA patients. SA resolved in eight, persisted in five, and appeared in one patient.

CONCLUSION

The relationship of SA with lower body mass index suggests that SA might have been underestimated in overweight patients. Despite apparent resolution of SA in most patients, pre-RT SA portended an increased risk of shoulder/arm morbidity. We argue that SA warrants further investigation. Incidentally, the observation of SA occurring after RT in one patient represents the second case of post-RT SA reported in the literature.

Isolated paralysis of the serratus anterior muscle successfully treated by surgical release of the distal portion of the long thoracic nerve

OBJECTIVES

Isolated paralysis of the serratus anterior (SA) muscle had been reported, especially in athletes. During SA fascial flap dissections, we observed that fascial and vascular structures can mechanically constrain the thoracic portion of the long thoracic nerve (LTN). Here, we assess the results of neurolysis of the thoracic segment of the LTN.

METHODS

A prospective multicenter study was conducted between December 1999 and June 2004. Every case of isolated palsy of the SA was included, after a Parsonage-Turner syndrome has been ruled out. Eighteen consecutive cases underwent such neurolysis. There were 14 men and 4 women. Their mean age was 30 years (17 to 49).

RESULTS

The operation took place 16.4 months (range, 4-72 months) after the onset of palsy. Pain relief usually occurred during the first postoperative month. At the longest follow-up most patients had recovered completely.

CONCLUSIONS

In the absence of spontaneous recovery from traumatic palsy, surgical release of the distal segment of the LTN is a minimally invasive, safe and efficient procedure. Results were best when surgery was performed within six months of the initial paralysis.

Isolated long thoracic nerve paralysis - a rare complication of anterior spinal surgery: a case report

Introduction

Isolated long thoracic nerve injury causes paralysis of the serratus anterior muscle. Patients with serratus anterior palsy may present with periscapular pain, weakness, limitation of shoulder elevation and scapular winging.

Case presentation

We present the case of a 23-year-old woman who sustained isolated long thoracic nerve palsy during anterior spinal surgery which caused external compressive force on the nerve.

Conclusion

During positioning of patients into the lateral decubitus position, the course of the long thoracic nerve must be attended to carefully and the nerve should be protected from any external pressure.

The journal: one year later

This article celebrates the first year anniversary of the Journal of Brachial Plexus and Peripheral Nerve Injury.