A Rare Cause of Cauda Equina Syndrome: Neuroendocrine Carcinoma of the Lung.

Cauda equina syndrome (CES) is a rare condition describing the constellation of symptoms resulting from the compression of the cauda equina. Metastatic lesions are a common cause of CES, with lung lesions often implicated as the primary source. A particularly rare cause of CES is leptomeningeal metastasis (LM) from primary solid tumors. In this case, a 63-year-old male presented with urinary and fecal retention, as well as altered sensation in the genitalia. The clinical diagnosis of CES was based on the constellation of symptoms. Computed tomography (CT) imaging demonstrated a metastatic lesion in the S2 and S3 sacral vertebral bodies, with extension into the right piriformis muscle. Magnetic resonance imaging (MRI) revealed an intramedullary lesion at L2 and leptomeningeal enhancement, indicative of metastasis. Further imaging identified a primary lesion in the right lower lobe of the lung, with additional metastases to the brain and liver. A pathological diagnosis of metastatic neuroendocrine carcinoma (NEC) was confirmed following a supraclavicular lymph node biopsy. The patient received steroid therapy, chemotherapy, and radiation to the pelvis. This case provides an important perspective on CES evaluation due to the scarcity of literature highlighting spinal metastases as the primary presentation in patients with NEC of the lung. The clinical diagnosis of CES should raise suspicion for metastasis and warrant further investigation.

Multiple schwannomas of cauda equina and peripherals: A case report.

Spinal schwannomas arising from the Schwann cells of the myelin sheath represent the most common intradural extramedullary tumors. However, occurrences of multiple pearly nerve sheath tumors is rare, and such cases affecting the cauda equina are often localized within the spinal canal of the lumbosacral vertebra on 1 nerve fiber. Herein, we present a case of multiple schwannomas involving distinct nerve fibers of the cauda equina. A 37-year-old female with a history of schwannoma presented with multiple space-occupying lesions in the lumbosacral canal in 2022. Due to a subsequent pregnancy (9 months), further examination and treatment were deferred. Lumbar magnetic resonance imaging performed in February 2024 revealed persistent findings of multiple, bead-like nodular masses within the L1-S1 segments, comparable in size and number to those observed in 2022. Contrast-enhanced MRI demonstrated homogenous enhancement throughout the lesions without evidence of bleeding or cystic components. Given these findings, a diagnosis of schwannoma was suspected. In March 2024, the patient was admitted to hospital for further surgical treatment, the pathological examination result of the resected specimen was consistent with the diagnosis of schwannoma. This case highlights the importance of preoperative magnetic resonance imaging for visualizing tumors, defining their relationship with the nerve roots, and guiding surgical planning. Accurate diagnosis by radiologists plays a vital role in optimal patient management in these cases.

Beyond Surgery: Navigating Postoperative Care for Cauda Equina Syndrome Through a Scoping Review.

OBJECTIVE: Cauda equina syndrome (CES) is a serious neurological injury that can result in permanent disability. Our objective was to review the evidence for rehabilitation strategies for CES in a scoping review. METHODS: A scoping review of the literature to identify rehabilitation strategies and their outcomes was performed. The search strategy used was: (Cauda equina syndrome) AND (treatment OR management OR intervention OR physio* OR bladder* OR neuro* OR stem cell OR repair OR rehab*) AND ("post?operat* OR post?surgical OR surgery"). MEDLINE, CINHAL, Prospero, Cochrane, ClinicalTrials.gov, EMBASE, Web of Science, PEDro, and eThos were searched. RESULTS: Eight studies of rehabilitation for CES were identified which assessed general rehabilitation, active rehabilitation in a spinal cord injury unit, multidisciplinary team involvement and follow-up, spinal manipulation, spinal cord stimulation and sacral nerve stimulation. Outcome measures used were inconsistent, study quality was low, and it was difficult to draw conclusions regarding the effectiveness of rehabilitation strategies. CONCLUSION: Despite the risk of devastating injury and a recent GIRFT pathway recommending rehabilitation post CES surgery, there is very limited literature on rehabilitation for CES. Future high-quality rehabilitation trials following CES surgery are needed to guide treatment decisions and optimise post-surgical outcomes.

Cauda Equina Cavernoma: A Case Report and Literature Review.

Cavernous hemangiomas (or cavernomas) are benign vasculature malformations that occasionally occur in the central nervous system (CNS). The vast majority is found supratentorial, but cavernomas also appear on the spine, usually intramedullary. Cavernomas in the cauda equina are extremely rare, with only a few cases reported in the literature. We report a case of a cavernoma of the cauda equina in a 69-year-old woman with low back pain and right sciatica for two years. Lumbar MRI showed an intradural mass lesion at the L1-L2 level. She underwent surgery with resection of the lesion, which confirmed the diagnosis of cavernous hemangioma. A good clinical outcome was achieved. In addition to the case report, we present a literature review on all reported cauda equina cavernomas, discussing their clinical presentations, imaging characteristics, histological findings, and surgical management.

What Degree of Radiological Compression Predicts Cauda Equina Syndrome: A Retrospective Study at a National Tertiary Centre.

OBJECTIVE: Cauda Equina Syndrome (CES) is diagnosed both clinically and radiologically. However, it's unclear if a specific degree of cauda equina compression (CEC) on imaging can confirm the diagnosis. This study aimed to identify an optimal percentage of prolapse to canal ratio (PCR) on MRI that correlates with CEC, facilitating reliable decision-making for CES symptoms. METHODS: A single-center retrospective case series analysis was conducted from 2020 to 2021. Sixty-one patients who underwent emergency lumbar discectomy within 48 hours of presentation were included, divided into a CES group and a disc prolapse (DP) group. CES cases were identified using ICD-10 code G83.4. PCR was calculated by dividing the width of the disc herniation by the total width of the spinal canal at the level of the herniation on single mid-sagittal T2 MRI scans, using the IC Measure software on Windows. RESULTS: CES most frequently occurred at the L4/5 level (37/61). The median PCR in CES cases was 76.19% (66.67 - 85.71), significantly higher than in DP cases, 48.08% (31.33 - 55.56) (p<0.001). A PCR threshold of 40% maximized sensitivity at 100% but had a specificity of 45%. Conversely, a threshold of 75% maximized specificity at 100% with a sensitivity of 50%. The optimal PCR, determined by the Youden index, was 66%, yielding a sensitivity of 75% and specificity of 97%, with an area under the curve (AUC) of 0.923. CONCLUSIONS: Simple radiological measurements of PCR can potentially triage CES patients and guide their management. Future studies should correlate PCR with clinical signs and symptoms for a comprehensive assessment.

Post-traumatic cauda equina concussion: Definition and description of the injury mechanism.

Despite being a prevalent clinical condition, cauda equina concussion has not been thoroughly elucidated in the literature. The aim of this study is to delineate the etiology and pathogenesis of cauda equina concussion and its associated clinical manifestations. Patients exhibiting clinical manifestations indicative of spinal cord injury and transient neurological deficits after spinal trauma were evaluated retrospectively. The pathogenesis was elucidated through correlating clinical presentations with radiological findings. Neurological deficits were categorized into two principal groups, symmetrical and asymmetrical. Non-penetrating fractures were classified to ascertain the relationship between the type of trauma and the ensuing neurological deficits. A cohort of 82 patients was diagnosed with cauda equina concussion. Among these, 58 had experienced vertical trauma resulting from falls, while 24 had encountered axial trauma in vehicular accidents. Stable spinal fractures were identified in 52 patients across multiple levels, whereas single-level fractures were observed in 30. Asymmetrical neurological deficits were detected in 51 (62.19%) patients, with a notably higher incidence among those subjected to vertical trauma (p < 0.014). The mean recovery time was 14.25 ± 15.16 h for sensory deficits and 11.25 ± 13.36 h for motor deficits in those patients. Notably, motor deficits resolved more expeditiously than sensory deficits in all cases presenting with both. Cauda equina concussion emerges as a frequently encountered clinical phenomenon attributable to the impact of high-energy vertical forces. Neurological deficits commonly manifest asymmetrically. The rapid resolution of neurological deficits presents challenges for the diagnostic process.

Can clinical presentation predict radiologically confirmed cauda equina syndrome: retrospective case review of 530 cases at a tertiary emergency department.

PURPOSE: Cauda equina syndrome (CES) may have significant individual consequences if diagnostic delays occur. Our aim was to evaluate the presenting subjective and objective features of patients with suspected CES in comparison to those with radiologically confirmed cauda equina compression (CEC).. METHODS: This was a retrospective analysis of all cases presenting with suspected CES to a tertiary emergency care unit over a two-year period. CEC was defined as radiological confirmation of CEC by Consultant Musculoskeletal (MSK) Radiologist report (MSK-CEC) and by measured canal occupancy due to an acute disc extrusion (> 75%)[measured by a Senior Spinal Surgeon (SP-CEC)]. Routine data collection was compared between categories. Chi square, multivariate regression analyses and ROC analysis of multiple predictors was performed. RESULTS: 530 patients were included in this analysis, 60 (11.3%) had MSK-CEC, and 470 had NO- CEC. Only 43/60 (71.7%) had emergent surgery. Those with MSK-CEC and SP-CEC were statistically more likely to present with bilateral leg pain [(MSK-CEC OR 2.6, 95%CI 1.2, 5.8; p = 0.02)(SP-CEC OR 4.7, 95%CI 1.7, 12.8; p = 0.003)]; and absent bilateral ankle reflexes [(MSK-CEC OR 4.3; 95% CI 2.0, 9.6; p < 0.001)(SP CEC OR 2.5; 95%CI 1.0, 6.19; p = 0.05)] on multivariate analysis. The ROC curve analysis acceptable diagnostic utility of having SP-CEC when both are present [Area under the curve 0.72 (95%CI 0.61, 0.83); p < 0.0001]. CONCLUSION: This study suggests that in those presenting with CES symptoms, the presence of both bilateral leg pain and absent ankle reflexes pose an acceptable diagnostic tool to predict a large acute disc herniation on MRI scan..

Herpes simplex encephalomyeloradiculitis initially presents with urinary retention.

Herpes simplex virus (HSV) infections necessitate careful management of urinary dysfunction and retention, which are underestimated conditions. Here, we present a rare case of HSV encephalomyeloradiculitis in a 76-year-old man, whose initial symptoms included urinary dysfunction and retention that alone lasted for approximately 1 week. Unlike in meningoencephalitis, high fever and headache were absent; however, the patient subsequently developed cauda equina syndrome and consciousness disturbance. Gadolinium-enhanced spinal MRI suggested enhanced cauda equina at the L2/3 level. Upon admission, he was treated for meningoencephalitis with acyclovir and steroid pulse therapy. Subsequent cerebrospinal fluid analysis result was positive for HSV DNA. A |brain MRI conducted 1 week after admission displayed high-intensity lesions in the white matter of the right temporal lobe, confirming HSV encephalomyeloradiculitis. These treatments were highly effective and gradually improved the patient's condition. He was discharged 1 month after hospitalization, and the urinary catheter was removed 2 weeks later. HSV infections can cause life-threatening encephalomyeloradiculitis. Therefore, both neurologists and urologists must pay attention to their occurrence and characteristics in clinical settings.

Systematic Review and Critical Appraisal of Cauda Equina Syndrome Management During Pregnancy.

Cauda equina during pregnancy represents a rare entity, with data regarding optimal treatment being very scarce in the pertinent literature. Given the scarcity of current evidence on the topic, this study conducts a systematic review and analysis of existing literature concerning cauda equina syndrome (CES) management in pregnant women. A comprehensive search was performed across multiple databases, yielding 26 level IV peer-reviewed articles that met the inclusion criteria. These studies collectively encompassed 30 pregnant patients with CES, with a mean age of 31.2 years and an average gestational age of 26 weeks. Disc herniation emerged as the primary cause in 73% of cases. Regarding surgical interventions, the prone position was utilised in 70% of cases, with 73% receiving general anaesthesia. Notably, third-trimester spinal surgeries exhibited a higher complete recovery rate compared to earlier trimesters. Minimally invasive spinal surgery demonstrated superior outcomes in terms of complete recovery and reduced risk of persistent post-operative symptoms when compared to open approaches. Moreover, patients undergoing caesarean section (CS) after spinal surgery reported higher rates of symptom resolution and lower symptom persistence compared to those with CS before spinal surgery or vaginal delivery post-spinal surgery. Despite these study's findings, the overall evidence base remains limited, precluding definitive conclusions. Consequently, the study underscores the importance of multidisciplinary team discussions to formulate optimal treatment strategies for pregnant individuals presenting with CES. This highlights a critical need for further research to expand the knowledge base and improve the guidance available for managing CES in pregnant populations.

Pediatric atypical teratoid/rhabdoid tumor in the cauda equina with rapid tumor progression: illustrative case.

BACKGROUND: Atypical teratoid/rhabdoid tumor (AT/RT) is an uncommon malignant neoplasm and rarely occurs in the spinal space, especially in the cauda equina. Only 8 cases of pediatric AT/RT of the cauda equina have been reported. Therefore, its clinical behavior and optimal treatment remain unclear. OBSERVATIONS: The authors describe the case of a 9-year-old boy who presented with progressive back and left leg pain. Initial magnetic resonance imaging showed an intradural extramedullary lesion at the L3-4 level, which progressed rapidly to the L2-5 level within a month. He underwent partial resection of the tumor with an L2-5 laminectomy. The histopathological diagnosis was AT/RT. He received adjuvant chemotherapy and radiotherapy, and his gait disturbance improved postoperatively. At 6 months' follow-up, disease recurrence was not observed. LESSONS: Although extremely rare, AT/RT should be included in the differential diagnosis for prompt therapeutic intervention. Safe resection with minimal functional impairment, followed by postoperative chemoradiation, can lead to tumor control and improve neurological function. https://thejns.org/doi/10.3171/CASE24219.

Concurrent multiple cerebral cavernous malformations and cauda equina paraganglioma: illustrative case.

BACKGROUND: Cauda equina neuroendocrine tumors (CENETs), previously known as cauda equina paragangliomas, and multiple cerebral cavernous malformations (CCMs) are uncommon conditions affecting the central nervous system. To the authors' knowledge, they have not been reported in the same patient. OBSERVATIONS: The authors present the case of a 45-year-old male with CENET and concurrent incidental MRI findings of multiple CCMs. Familial CCMs are associated with mutations in the KRIT1 (CCM1), MGC4607 (CCM2), and PDCD10 (CCM3) genes. Peripheral paragangliomas have been associated with mutations in succinate dehydrogenase (SDHx), RET (multiple endocrine neoplasia 2), VHL (von Hippel-Lindau syndrome), and NF1 (neurofibromatosis type 1) genes. Except for a single case, cauda equina paragangliomas have not been associated with any underlying genetic mutations. LESSONS: It is unclear whether the co-occurrence of these two rare conditions in the same patient is coincidental or suggests a possible shared pathogenesis. https://thejns.org/doi/10.3171/CASE24102.

Cauda equina syndrome due to posttraumatic syringomyelia in conus medullaris - A case report.

Background: Most posttraumatic syringomyelias occur in the cervical or thoracic spinal cord, where they contribute to myelopathic deficits. Here, a 40-year-old patient presented with the left leg monoparesis due to syringomyelia involving the conus medullaris 10 years after an L2 vertebral "crush" fracture. Case Description: Ten years following an L2 vertebral "crush" fracture, a 40-year-old male presented with the new onset of left lower leg paresis. The magnetic resonance imaging showed a T12-L1 syrinx associated with accompanying high-intensity areas above the syrinx located between the T11 and T12 levels. One month after placing a syringosubarachnoid (SS) shunt, both the syrinx and high-intensity area rapidly disappeared, and the left distal motor weakness resolved. Conclusion: Ten years following an L2 "crush" fracture, a 40-year-old male presented with the new onset of a cauda equina syndrome secondary to a posttraumatic T12-L1 syringomyelia causing expansion of the conus medullaris.

Atypical Choroid Plexus Tumor of the Cauda Equina With Metastases to the Spinal Cord and Brain.

We report a case of a 57-year-old man with a tumor arising from the cauda equina with spinal cord and intracranial metastases in the basal cisterns and along the cranial nerves. He presented with severe lower back pain and mild gait imbalance. His imaging revealed a large mass in the lumbosacral region with involvement of the cauda equina, intradural extramedullary enhancing metastases in the thoracic spinal canal, and intracranial metastases in the suprasellar cistern and along both trigeminal and facial/vestibulocochlear nerve complexes. Pathological examination of the resected thoracic spinal cord mass showed an atypical papillary proliferation with moderate nuclear pleomorphism and rare mitotic figures. While the morphologic and immunophenotypic features were consistent with the diagnosis of a choroid plexus tumor, the atypical location for this entity required the exclusion of other epithelioid tumors with papillary architecture. Additional immunohistochemical markers were used to exclude a metastatic adenocarcinoma, a papillary variant of a meningioma, and a papillary variant of an ependymoma. Ultimately, methylation-based tumor profiling determined that the methylation class was a match for "plexus tumor" resulting in the integrated diagnosis of the tumor with features of choroid plexus papilloma. This is a unique presentation for both the location and the metastatic spread. The methylation profile was instrumental in establishing this diagnosis.

Clear cell meningioma of the filum terminale in a 44-year-old woman - case report.

Clear cell meningioma (CCM) is a rare subtype of meningioma, especially unusual as a neoplasm of the filum terminale. Clear cell meningioma seems to have a more aggressive nature and a higher risk of recurrence than WHO grade I meningiomas. A 44-year-old woman presented with lower back pain radiating to the left leg and mild weakness in the left leg. Magnetic resonance imaging (MRI) showed a well-demarcated, intradural lesion filling the spinal canal at the L3-S1 levels and compressing the cauda equina. The patient underwent laminectomy from L3 to S1. During the operation, the filum terminale was identified as a structure that was disappearing into the tumor. The filum terminale was cut and the tumor was totally removed in one piece. Pathological findings were indicative of the diagnosis of clear cell meningioma, CNS WHO G2. Postoperative magnetic resonance imaging at 6 months showed no residual mass. Total surgical excision of the CCM of the spinal cord should be chosen as the optimal treatment. In addition, radiological follow-up is equally important due to the high risk of recurrence. Our case is unusual in that the tumor's location was the filum terminale.

Revolutionizing Bladder Health: Artificial-Intelligence-Powered Automatic Measurement of Bladder Volume Using Two-Dimensional Ultrasound.

INTRODUCTION: Measuring elevated post-void residual volume is important for diagnosing urinary outflow tract obstruction and cauda equina syndrome. Catheter placement is exact but painful, invasive, and may cause infection, whereas an ultrasound is accurate, painless, and safe. AIM: The purpose of this single-center study is to evaluate the accuracy of a module for artificial-intelligence (AI)-based fully automated bladder volume (BV) prospective measurement using two-dimensional ultrasound images, as compared with manual measurement by expert sonographers. METHODS: Pairs of transverse and longitudinal bladder images were obtained from patients evaluated in an urgent care clinic. The scans were prospectively analyzed by the automated module using the prolate ellipsoid method. The same examinations were manually measured by a blinded expert sonographer. The two methods were compared using the Pearson correlation, kappa coefficients, and the Bland-Altman method. RESULTS: A total of 111 pairs of transverse and longitudinal views were included. A very strong correlation was found between the manual BV measurements and the AI-based module with r = 0.97 [95% CI: 0.96-0.98]. The specificity and sensitivity for the diagnosis of an elevated post-void residual volume using a threshold ≥200 mL were 1.00 and 0.82, respectively. An almost-perfect agreement between manual and automated methods was obtained (kappa = 0.85). Perfect reproducibility was found for both inter- and intra-observer agreements. CONCLUSION: This AI-based module provides an accurate automated measurement of the BV based on ultrasound images. This novel method demonstrates a very strong correlation with the gold standard, making it a potentially valuable decision-support tool for non-experts in acute settings.

The predictive value of intraoperative bulbocavernosus reflex monitoring for postoperative voiding function in patients with conus medullaris and cauda equina tumors: a retrospective single center study.

BACKGROUND CONTEXT: Surgical resection is the preferred treatment in most conus medullaris and cauda equina tumor (CMCET) cases. However, total resection is usually challenging to obtain and has a strong possibility of causing various complications if forcibly attempted. Intraoperative neurophysiological monitoring (IONM) has become a necessary adjunctive tool for CMCET resection. PURPOSE: The current study aimed to evaluate the application value of bulbocavernosus reflex (BCR) monitoring in CMCET surgery. STUDY DESIGN: A retrospective clinical study. PATIENT SAMPLE: The medical records of patients who underwent CMCET resection by the same neurosurgical team at our hospital from September 2020 to June 2022 were retrospectively reviewed. IONM was conducted in all surgeries. According to inclusion criteria and exclusion criteria, ultimately, 105 patients were enrolled in the study. OUTCOME MEASURES: The voiding function was assessed before surgery, 1 month after, and 6 months after surgery using the Neurogenic Bladder Symptom Score (NBSS). If the NBSS obtained 1 month after surgery exceeds 9 points than that before surgery, it can be considered that the patient suffered new-onset postoperative voiding dysfunctions (PVDs). Moreover, if the NBSS could restored (less than 9 points higher than before the surgery) at 6 months after surgery, it was defined as a short-term PVD. Otherwise, it was defined as a long-term PVD. METHODS: The amplitude reduction ratios (ARRs) of bilateral BCR waveforms were calculated and compared between patients with PVDs and those without. The receiver operating characteristic curve analysis was subsequently applied to determine the cut-off value of the maximal and minimal ARRs for predicting PVDs. RESULTS: The maximal and minimal ARRs were significantly correlated with short-term and long-term PVDs (p<.001 for all comparisons, Mann-Whitney U test). The threshold values of maximal ARR for predicting short-term and long-term PVD were 68.80% (AUC=0.996, p<.001) and 72.10% (AUC=0.996, p<.001), respectively. While those of minimal ARR were 50.20% (AUC=0.976, p<.001) and 53.70% AUC=0.999, p<.001). CONCLUSIONS: The amplitude reduction of intraoperative bilateral BCR waveforms showed high predictive value for PVDs.

Primary Cauda Equina Lymphoma Mimicking Meningioma.

Background: Spinal cord lymphomas represent a minority of extranodal lymphomas and often pose diagnostic challenges by imitating primary spinal tumors or inflammatory/infective lesions. This paper presents a unique case of primary cauda equina lymphoma (PCEL) and conducts a comprehensive review to delineate the clinical and radiological characteristics of this rare entity. Case Report: A 74-year-old male presented with progressive paresthesia, motor weakness, and symptoms indicative of cauda equina syndrome. Neurological examination revealed paraparesis and sphincter dysfunction. Imaging studies initially suggested an intradural meningioma. However, surgical intervention revealed a diffuse large B-cell lymphoma infiltrating the cauda equina. Findings: A systematic review of the pertinent literature identified 18 primary cauda equina lymphoma cases. These cases exhibited diverse clinical presentations, treatments, and outcomes. The mean age at diagnosis was 61.25 years for women and 50 years for men, with an average follow-up of 16.2 months. Notably, 35% of patients were alive at 18 months, highlighting the challenging prognosis associated with PCEL. Discussion: Primary spinal cord lymphomas, especially within the cauda equina, remain rare and diagnostically complex due to their nonspecific clinical manifestations. The review highlights the need to consider spinal cord lymphoma in patients with neurological symptoms, even without a history of systemic lymphoma. Diagnostic Approaches: Magnetic resonance imaging (MRI) serves as the primary diagnostic tool but lacks specificity. Histopathological examination remains the gold standard for definitive diagnosis. The review underscores the importance of timely biopsy in suspected cases to facilitate accurate diagnosis and appropriate management. Management and Prognosis: Current management involves biopsy and chemotherapy; however, optimal treatment strategies remain ambiguous due to the rarity of PCEL. Despite aggressive therapeutic interventions, prognosis remains poor, emphasizing the urgency for enhanced diagnostic and treatment modalities. Conclusions: Primary cauda equina lymphoma poses diagnostic and therapeutic challenges, necessitating a high index of suspicion in patients with atypical spinal cord symptoms. Collaborative efforts between neurosurgical, oncological, and infectious diseases teams are imperative for timely diagnosis and management. Advancements in diagnostic precision and therapeutic options are crucial for improving patient outcomes.

Novel Technologies to Address the Lower Motor Neuron Injury and Augment Reconstruction in Spinal Cord Injury.

Lower motor neuron (LMN) damage results in denervation of the associated muscle targets and is a significant yet under-appreciated component of spinal cord injury (SCI). Denervated muscle undergoes a progressive degeneration and fibro-fatty infiltration that eventually renders the muscle non-viable unless reinnervated within a limited time window. The distal nerve deprived of axons also undergoes degeneration and fibrosis making it less receptive to axons. In this review, we describe the LMN injury associated with SCI and its clinical consequences. The process of degeneration of the muscle and nerve is broken down into the primary components of the neuromuscular circuit and reviewed, including the nerve and Schwann cells, the neuromuscular junction, and the muscle. Finally, we discuss three promising strategies to reverse denervation atrophy. These include providing surrogate axons from local sources; introducing stem cell-derived spinal motor neurons into the nerve to provide the missing axons; and finally, instituting a training program of high-energy electrical stimulation to directly rehabilitate these muscles. Successful interventions for denervation atrophy would significantly expand reconstructive options for cervical SCI and could be transformative for the predominantly LMN injuries of the conus medullaris and cauda equina.