Revolutionizing Spine Surgery: The Impact of Intraoperative Monitoring in LMICs

Prompt

Title page Title: Intraoperative monitoring for spine surgery in LMICs: Applications, outcomes and access disparities Highlights IONM improves surgical precision and safety in LMICs despite resource limitations. Multimodal IONM reduces neurological deficits, costs, and corrective surgeries. Challenges include limited infrastructure, workforce, funding, and standardisation. Risks involve false positives, false negatives, and signal interpretation issues. Solutions involve strengthening systems, forming partnerships, and global training. Abstract Intraoperative neuromonitoring (IONM) has become an essential tool in modern spine surgery to protect neural structures and minimise the risk of neurological complications. Various IONM techniques, such as motor evoked potentials (MEPs), electromyography (EMG), transcranial motor stimulation and somatosensory evoked potentials (SSEPs), have been developed to allow surgeons to monitor spinal cord and nerve function in real time and make critical decisions that improve surgical outcomes and reduce neurological deficits. IONM has been effective in improving surgical precision and patient safety in low- and middle-income countries (LMICs), where spine surgery for degenerative conditions, spinal cord injuries, tumours and deformities is further complicated by limited healthcare resources. Multimodal IONM is particularly useful in these regions to reduce post-operative neurological deficits and reduce costs by avoiding the need for corrective surgery and extensive rehabilitation. However, there are challenges including infrastructure and workforce deficiencies, economic constraints, lack of standardised guidelines and variability of IOMN that limit wider implementation. IONM also does not eliminate intraoperative complications, where false positives, false negatives and signal interpretation problems remain risks. However, the integration of IONM into high-risk spine surgery is a promising strategy to improve outcomes, particularly in resource-limited settings. Keywords: Intraoperative Neurophysiological Monitoring, Spine Surgeries, Low-and-Middle-Income Countries, Global Spine Surgery Abbreviations IONM; Intraoperative Neurophysiological Monitoring, HIC; High Income Country, MEP; Motor-Evoked Potential, SSEP; Somatosensory-Evoked Potential, LMIC; Low- and Middle-income Country, MIC; Middle Income Country, PE-TLIF; Percutaneous Endoscopic- Transforaminal Lumbar Interbody Fusion, SCI; Spinal Cord Injury, ALIF; Anterior Lumbar Interbody Fusion, LLIF; Lateral Lumbar Interbody Fusion, WSC; World Spine Care, CIGMIT; Centre for Image Guidance and Minimally Invasive Therapy, TES; Transcranial Electrical Stimulation, TMS; Transcranial Magnetic Stimulation, EMG; Electromyography, TOLF; Thoracic Ossification of the Ligamentum Flavum 1. Introduction Intraoperative neurophysiological monitoring (IONM) has emerged as an indispensable tool in modern surgery, providing real-time feedback on neurophysiological signals to reduce the risk of neurological injury during procedures [1-3]. Its applications span a wide range of surgical specialties, including brain and spine surgery, vascular interventions, peripheral nerve operations, orthopaedic procedures, and otolaryngology [1]. Since its early inception in the 1930s with direct cortical stimulation for epilepsy surgery, IONM has evolved significantly, particularly with the introduction of commercial IONM machines in the 1980s and motor-evoked potentials (MEPs) in the 1990s, which enabled more precise monitoring of corticospinal tract function [2]. In high-income countries (HICs), multimodal IONM techniques have become standard in spine surgery to prevent neurological damage by monitoring MEPs and somatosensory-evoked potentials (SSEPs) [4,5]. Despite its widespread adoption in HICs, the use of IONM in low- and middle-income countries (LMICs) remains uneven. Middle-income countries (MICs) such as China and Egypt have made notable progress, incorporating IONM into routine spine surgeries with significant success in tumour resections and intraoperative decision-making [6-8]. However, in low-income nations, where even basic surgical needs are unmet [9], the implementation of advanced technologies such as IONM remains impractical. While the progress of IONM has been primarily observed in certain LMICs, they continue to face considerable barriers, including limited equipment, unreliable power supplies, a shortage of trained professionals, and high costs [4,10,11]. This review, the first of its kind to focus on the role of IONM for spine surgery in LMICs, highlights the need for strategic investment and capacity building to harness the potential of IONM to improve patient outcomes, particularly for high-risk spine surgery. 2. Methodology This narrative review of the role of intraoperative neurophysiological monitoring in neurosurgery in LMICs used a rigorous methodology involving a comprehensive search of the published literature. The inclusion criteria allowed for studies of different designs, including observational, case-series, cohort and randomised controlled trials. The review included articles published in English from the inception until 2024. The studies included in the review involved patients who received spinal surgical care with the aid of IONM in LMICs. Databases including PubMed, EMBASE, the Cochrane Library and SCOPUS were used for the literature search. Specific search terms including 'intraoperative neurophysiological monitoring', 'IONM', ‘spine surgery’, 'neurosurgery', ‘orthopaedic surgery’, 'low-middle income countries', and 'resource-limited settings', were used. This approach ensured that the literature search was targeted to our specific area of interest. In addition, a manual search was conducted to identify references to recently published case-specific reviews to provide further information. A summary of the methodology is provided in table 1. 3. An overview of the types of IONM techniques used in spinal surgery 3.1. Motor Evoked Potentials MEPs are generated by electrically stimulating the brain, with the response recorded over the spinal cord or muscles. These signals can originate from either the spinal cord (D or I waves) or the motor cortex and are detected through electrodes placed on upper and lower extremity muscles. This allows real-time monitoring of corticospinal tract activity during surgery [2,12]. Muscle-based MEPs (Tc-mMEPs) are preferred due to the ease of generating and recording these signals [2]. Prior to the development of MEPs, the Stagnara wake-up test was used to assess corticospinal tract integrity, but it caused significant delays and lacked continuous monitoring. MEPs, by contrast, provide greater sensitivity in detecting postoperative motor deficits, enhancing surgical safety and efficacy [13]. 3.2. Electromyography The electromyography (EMG) technique has proven effective in assessing the integrity of nerve function during spinal procedures. It has the capability to identify specific nerves that may be disrupted during operations such as spinal tumor resection. Moreover, EMG plays a crucial role in safeguarding nerves during surgery, particularly in situations involving potential peripheral damage or blunt trauma. This technique facilitates smooth and safe surgical interventions that involve dissection or manipulation of nerves, thereby helping to protect neural structures and prevent further injury [14]. 3.3. Transcranial Motor Stimulation Transcranial motor evoked potentials (TcMEPs) are muscle action potentials generated through transcranial brain stimulation. These signals are crucial for assessing motor system functionality and integrity, particularly during surgical interventions, as they provide valuable information about the corticospinal tract [15]. Transcranial motor stimulation can be divided into two types: transcranial electrical stimulation (TES) and transcranial magnetic stimulation (TMS). However, TES is preferred over TMS for generating MEPs, to stimulate the corticospinal tract, as TES is more resistant to anaesthesia [2]. 3.4. Somatosensory Evoked Potentials SSEPs are a vital component of IONM, used to assess the integrity of the dorsal column-medial lemniscus pathway. This pathway plays a crucial role in tactile discrimination, vibration sensation, form recognition, and conscious proprioception [3]. Typically, SSEPs are elicited by stimulating the median or posterior tibial nerves and recording the resulting signals in the cortical somatosensory area. These signals provide insight into potential intraoperative nerve damage [2]. SSEPs serve as a reliable means to monitor the function and overall integrity of nerve tissue [3]. However, despite their high specificity and sensitivity, SSEPs have limitations. They primarily monitor sensory pathways and do not assess motor pathways, which can lead to “false-negative” results. This limitation arises when SSEPs are used in isolation to monitor intraoperative nerve function, as they may fail to detect motor pathway injuries [3]. The overview of the types of IONM techniques used in spine surgery has been summarised in Table 2. 4. IONM spine surgery applications in LMICs: advantages and complications/adverse effects In LMICs, IONM is primarily indicated for patients undergoing spine surgery for high-risk conditions such as traumatic spinal cord injuries, congenital deformities, and intramedullary tumours. These procedures carry significant neurological risks due to the complex anatomy and essential functions of the spinal cord [16,17]. The use of IONM enables real-time detection of intraoperative neurological deficits, allowing for timely interventions that can substantially improve postoperative outcomes [4]. Given the limited resources and technical expertise in many LMICs, IONM plays a vital role in optimising surgical safety and efficacy, improving the likelihood of functional recovery in healthcare environments with considerable challenges [18]. 4.1. Degenerative Spine Surgery The significance of IONM in spine surgery, particularly for degenerative spine conditions, is increasingly recognized. For instance in Latin America, 92% of surgeons view IONM as essential for improving patient outcomes, particularly in cases where nerve compression could lead to motor deficits or chronic pain, rather than merely serving a medicolegal function. However, financial limitations restrict access, with only 57% of surgeons reporting regular use of IONM, which is often reserved for complex cases like scoliosis correction while simpler degenerative conditions may be overlooked [19]. In complex degenerative cases, such as thoracic ossification of the ligamentum flavum (TOLF) leading to spinal stenosis, IONM has demonstrated its utility. During en bloc laminectomy for TOLF, 74% of patients exhibited no significant IONM changes and achieved favourable postoperative outcomes without neurological deficits. However, among patients with both SSEPs and MEPs alerts that did not recover intraoperatively with 9% experiencing permanent neurological complications. This underscores IONM’s critical role in monitoring and reducing intraoperative risks [20]. In indirect decompression surgeries such as anterior lumbar interbody fusion (ALIF) and lateral lumbar interbody fusion (LLIF), neurophysiological parameters showed no significant changes, and none of the patients developed postoperative neurological deficits [21]. The use of multimodal IONM techniques provided valuable intraoperative data, preventing postoperative deficits, particularly in complex procedures like ALIF and LLIF [4, 21]. This not only demonstrates the safety of using IONM in minimally invasive lumbar spine surgery, but also gives surgeons confidence that nerve damage can be prevented. [21] IONM is especially crucial in minimally invasive procedures, such as percutaneous endoscopic transforaminal lumbar interbody fusion (PE-TLIF), often performed to treat lumbar spinal stenosis. Studies show that multimodal IONM (MEPs, SSEPs and EMG) achieved 100% sensitivity in detecting neurological complications intraoperatively. Only 6% of patients experienced temporary neurological deficits, all of which resolved within one week, further emphasising IONM’s effectiveness in minimising false negatives and preventing long-term damage in degenerative lumbar conditions [7]. Interestingly, the combination of intelligent EMG with SSEPs and MEPs during spine surgery has been shown to significantly increase the sensitivity of neural damage detection compared to single-modality monitoring. In one study, 28% of patients exhibited abnormal signals during surgery; however, immediate adjustments based on IONM feedback prevented postoperative neurological deficits [22]. Contrastingly, some evidence suggests that IONM may not be necessary for simpler degenerative spine conditions in LMICs. A study conducted in a Sub-Saharan African (SSA) country reported successful outcomes in lumbar spine surgeries without IONM, showing perioperative morbidity of less than 2% and 92% patient satisfaction. [23] While IONM is invaluable in complex spine surgeries, a selective, context-sensitive approach may maximise its benefits in LMICs, where successful outcomes can still be achieved in simpler cases without its routine use. 4.2. Spinal Cord Injury Surgery In LMICs, IONM plays a critical role in improving outcomes for patients with spinal cord injuries (SCIs). By enabling continuous neurological assessments during surgery, IONM allows for real-time adjustments, replacing the outdated wake-up test, which had significantly lower accuracy [16,17]. For instance, in Egypt, IONM demonstrated 100% sensitivity, 80% specificity, and a 62.5% positive predictive value [4]. Reversible IONM alerts were associated with a significantly reduced incidence of postoperative neurological deficits. In settings with limited resources, using a 50% reduction in MEP amplitude as a warning threshold greatly enhanced patient safety. Moreover, IONM successfully detected intraoperative changes in 9 cases of selective dorsal rhizotomy, with only one case experiencing mild postoperative deterioration [18]. Postoperatively, IONM also has advantages in reducing postoperative neurological complications in spinal cord and spinal root surgery for congenital spinal pathologies, with a reduction in complications from 2.6% to 0.8%. [17] In addition, 42.6% of patients with incomplete SCI showed significant neurological recovery in a different study. [16] However, this high sensitivity of IONM had the potential to lead to type 1 errors, usually due to changes in anaesthesia or technical malfunction. Nevertheless, its overall benefits in improving surgical precision and safety are widely recognised, particularly in traumatic SCI [17]. 4.3. Spinal Tumour Surgery In LMICs, the use of IONMs in spinal tumour surgery also offers significant benefits, particularly in improving surgical outcomes and preserving neurological function. Multimodal IONM, which includes techniques such as SSEPs and MEPs, allows for real-time monitoring of spinal cord function, thus providing crucial feedback during delicate surgical procedures. This capability enables surgeons to make immediate adjustments to their surgical techniques. Multimodal IONM is a crucial technique for safeguarding neural structures during spine surgery, particularly when addressing intramedullary spinal cord lesions [18,24]. Multimodal IONM significantly improved the extent of tumour resection in patients with spinal cord ependymomas, correlating with better postoperative neurological outcomes in Egypt [8]. Specifically, patients who underwent IONM-assisted surgery achieved an average tumour resection rate of 90%, compared to only 70% in non-monitored cases [8]. Furthermore, IONM helped mitigate the risk of postoperative deficits, enabling more aggressive tumour resections while maintaining functional status, with a reported reduction in neurological deficits from 25% to 5% [4]. IONM not only aids in identifying critical neural structures but also plays a vital role in decision-making during spine tumour surgeries, ultimately leading to improved patient safety [3]. Particularly, the incidence of intraoperative neurophysiological changes can be as high as 30% in patients undergoing spine surgeries, with IONM effectively alerting surgeons to take corrective actions in 80% of these cases [20]. In LMICs, where the resources for postoperative rehabilitation may be limited, the ability to minimise neurological complications through effective monitoring becomes even more critical. Another benefit is the potential reduction in healthcare costs associated with managing postoperative complications. Successful implementation of IONM can decrease the need for extensive rehabilitation or further surgical interventions, thereby alleviating the financial burden on both healthcare systems and patients [18]. Specifically, hospitals using IONM reported a reduction in postoperative complication rates by approximately 50%, translating to savings of up to $30,000 per patient. [25] This is particularly relevant in LMICs, where economic constraints often dictate treatment approaches. 4.4. Spinal Deformities IONM has become a critical tool in the surgical management of spinal deformities, particularly in LMICs. A West African hospital reported that 39% of patients undergoing spinal deformity surgery experienced intraoperative signal changes, primarily due to surgical positioning or traction, which were resolved by the end of the procedure. This highlights the potential of IONM to detect and address neurological issues early, as 100% of non-osteotomy-related complications were successfully managed intraoperatively, preventing long-term deficits [26]. A separate study revealed that compared to patients who did not receive IONM during spinal deformity corrections, those who did had a 70% reduction in neurological complications. [3] Conditions such as scoliosis, kyphosis, and lordosis pose significant neurological risks, but the use of IONM has demonstrated substantial advantages in improving surgical outcomes and reducing these risks. [20] In kyphosis surgeries, particularly those involving vertebral osteotomies, IONM has been shown to reduce the risk of neurological deficits by 75%, making it a crucial tool in complex spinal procedures [3]. Similarly, in lordosis correction surgeries, IONM aids in monitoring spinal cord and nerve root integrity during decompression and fusion, resulting in improved neurological outcomes for 85% of patients [27]. The real-time feedback provided by IONM is particularly valuable in scoliosis surgery, where spinal curvature can compress the spinal cord and nerves. IONM enables timely interventions, improving surgical outcomes and safeguarding neurological integrity [26]. In Ghana, IONM detected neuromonitoring changes in half of the patients undergoing vertebral column resection (VCR) for early-onset scoliosis, leading to immediate corrective measures and improved outcomes [28]. IONM has primarily replaced the intraoperative wake-up test, which was previously used to assess neurological function during deformity surgeries. Studies from India have shown that IONM significantly reduced the need for such tests and improved patient safety by allowing real-time intervention. [29] A deeper analysis of IONM by comparing unimodal and multimodal monitoring techniques revealed that IONM detects neurological events with a sensitivity of 93% and 100% during scoliosis surgery and percutaneous endoscopic TLIF (PE-TLIF) surgery respectively. [6,7] In Chen’s study, neurological complications occurred in only 6% of patients, all of which were temporary and resolved within seven days. [7] The cost-effectiveness of IONM is particularly notable in LMICs, where healthcare resources are limited. By reducing the need for additional corrective surgeries due to undetected intraoperative complications, IONM can lead to significant savings. Studies report that IONM reduced postoperative hospital stays by nearly 50% for scoliosis patients, alleviating financial burdens and improving patient prognosis. [30,31] 5. Limitations with IONM usage and disparities in access in low-resource settings The implementation of IONM during spine surgeries in low-resource settings, particularly in LMICs, faces multiple challenges that hinder its widespread adoption and effectiveness. These challenges can be categorised into several key areas: infrastructural deficiencies, economic constraints, workforce shortages, ethical dilemmas, lack of standardised guidelines, and variability in adoption. 5.1. Infrastructural and Workforce Deficiencies Inadequate surgical infrastructure is a major obstacle to the effective use of IONM in many LMICs. A significant issue is the lack of essential equipment, such as advanced neuromonitoring systems, in operating theatres—equipment crucial for real-time monitoring during surgeries. In Brazil, although most spine surgeons recognised the importance of IONM, 68% of hospitals lacked adequate neuromonitoring capabilities, severely limiting the use of advanced surgical technologies. [19] Similarly, hospitals in rural areas of India often rely on outdated or insufficiently advanced neuromonitoring systems that do not meet contemporary standards. [4] Additionally, unreliable electricity supply further complicates the implementation of IONM, as exemplified by Kenya, where power outages disrupted 30% of surgical procedures, undermining patient safety. [14] These infrastructural barriers significantly limit the capacity of healthcare providers in LMICs to use IONM effectively, jeopardising both patient safety and surgical outcomes. Successful implementation of IONM relies on a specialised workforce that includes trained technicians and neurophysiologists. In addition, ongoing education and training for surgeons and support staff are necessary for the effective use of IONM during procedures. However, surveys indicate that over 50% of healthcare facilities in certain regions lack personnel proficient in IONM technology [32], with only 30% of neurosurgeons feeling adequately trained to use IONM, leading to inconsistent application in surgical practice in another region. [25] The shortage of training programs and dedicated professionals continues to be a major barrier [18]. If these workforce shortages are not addressed, the potential benefits of IONM in improving patient outcomes will remain largely untapped in LMICs. 5.2. Economic Constraints and Ethical Concerns The high cost of IONM systems, coupled with ongoing operational expenses, presents a substantial barrier to adoption in LMICs. In many LMICs, the shortage of trained professionals limits access to IONM. In Latin America, for instance, over 95% of spine surgeons recognise the value of IONM, but high costs hinder its widespread use [33]. In fact, 70% of hospitals in an LMIC cited cost as a major obstacle to IONM implementation. [18] Limited government funding and insurance coverage exacerbate the problem, often forcing patients to bear the financial burden. For instance, in Southeast Asia, patients reported spending up to 40% of their annual income on spinal surgeries involving IONM, illustrating the unsustainable economic strain. [20] In Brazil, the cost per procedure can exceed $2,000, making IONM inaccessible to many within the already strained public healthcare system. [34] The ethical challenges of implementing IONM in LMICs often centre around resource allocation. In underfunded healthcare systems, decision-makers frequently prioritise basic healthcare needs over advanced technologies, such as IONM, leading to moral dilemmas for healthcare providers. For instance, 65% of hospitals in Latin America chose not to adopt IONM due to concerns about allocating limited resources [26]. Similar challenges exist in Nigeria, where healthcare providers must weigh the benefits of IONM against pressing health needs such as maternal and child healthcare. [4] These ethical dilemmas highlight the broader tension between introducing advanced medical technologies and addressing fundamental health needs in resource-limited environments. 5.3. Lack of Standardised Guidelines and Variability in IONM Adoption The absence of standardised protocols for IONM during spine surgeries introduces significant variability in its application. Without clear guidelines, hospitals may adopt inconsistent monitoring strategies, leading to variability in surgical outcomes. For example, a 40% discrepancy in IONM protocols across African hospitals contributed to uneven success rates in spinal surgeries [21]. This inconsistency is mirrored in India, where non-standardised institutional practices complicate surgical decision-making and patient care [4]. Additionally, it has been reported that many global spine care partnerships lacked formal needs assessments and evaluation metrics, limiting their long-term effectiveness [3]. The lack of cohesive guidelines also results in challenges such as false-positive and false-negative IONM readings, which can lead to unnecessary surgical interventions or misplaced confidence in patient safety. The variability in IONM adoption across LMICs further exacerbates disparities in access and outcomes. While some institutions integrate IONM into surgical practices, others struggle to implement even basic neuromonitoring techniques. In a South Asian study, only 20% of facilities utilised IONM, and those that did experienced a 50% reduction in postoperative neurological deficits. [3] Furthermore in Pakistan, a survey found that only 15% of spinal surgery centres employed IONM, resulting in higher rates of complications compared to hospitals with access to neuromonitoring. [30] This variability is influenced by regional economic conditions, access to training, and institutional policies, making it essential to address these disparities to improve surgical outcomes in low-resource settings. 5.4. Limitations of IONM Technology IONM is not without its limitations, particularly in the context of spinal surgeries. Anatomical variability, especially in patients with severe deformities, can complicate signal interpretation, leading to false readings or misinterpretations. Extensive manipulation during scoliosis correction can disrupt normal anatomical relationships, increasing the risk of complications such as nerve root damage or haematoma formation, which may not be immediately detectable by IONM [3]. Particularly, MEPs were inconclusive in 20% of scoliosis patients with significant anatomical distortions. [25] In kyphosis surgeries, reliance on IONM can sometimes cause delays, as surgeons may hesitate to proceed without clear signals, thereby increasing the risks associated with prolonged operative times and anaesthesia exposure [7]. Additionally, while IONM can detect many intraoperative complications, it cannot prevent all neurological damage. This is particularly true in procedures involving structural alterations of the spine, such as osteotomies or significant alignment changes, which may result in irreversible deficits [26]. Additionally, the presence of surgical hardware, such as rods and screws, can create artefacts in IONM readings, complicating data interpretation and potentially masking genuine neurological issues during kyphosis and lordosis corrections [20]. 6. Adoption of effective strategies for the successful use of IONM in low-resource settings 6.1. Multidisciplinary Engagement for IONM Usage Across LMICs The expansion of IONM in LMICs hinges on a multidisciplinary approach involving spine surgeons, anesthesiologists, neurophysiologists, and technologists. Countries like Brazil and India have proven that collaborative efforts between these professionals are crucial for the successful implementation of IONM, leading to improved surgical outcomes [4,11]. Central to this collaborative approach is real-time communication and teamwork during surgeries, enabling the early detection and prevention of neurological injuries. For instance, coordinated efforts among surgeons, anesthesiologists, and neuromonitoring specialists allow for prompt responses to intraoperative changes, reducing the risk of postoperative complications [1,12]. 6.2. Building Healthcare Infrastructure to Support Advanced Technologies A key factor in the successful adoption of IONM in LMICs is the development of robust healthcare infrastructure capable of supporting advanced spine surgical technologies. Many facilities in LMICs face infrastructural challenges that impede the implementation of IONM. For example, at Cairo University in Egypt, the initial introduction of IONM encountered issues with electrical grounding and limited access to anaesthetic agents [10]. However, addressing these challenges led to improved hospital infrastructure, better operational efficiency, and enhanced patient safety. The World Spine Care (WSC) initiative highlights the necessity of strengthening healthcare infrastructure in underserved regions, particularly where basic medical resources, such as reliable electricity and surgical tools, are lacking. By partnering with local hospitals and international organisations, WSC has made significant strides in improving spine care in areas with minimal resources [35]. This illustrates that even in low-resource settings, overcoming infrastructural barriers can lead to significant advancements in surgical care. 6.3. National and Global Strategies for Expanding IONM Usage The expansion of IONM in LMICs requires coordinated national and global strategies. These strategies should focus on integrating IONM into existing healthcare systems through cost-effective solutions. For example, in Thailand, the government mandates economic impact studies before including new treatments in the National Health Security Care system. Research has shown that, despite the initial costs of IONM, the long-term benefits – such as reduced postoperative complications – make it a cost-effective option for healthcare systems [36]. Partnerships between governments, private companies, and nonprofit organisations play a critical role in the expansion of IONM in LMICs. The Centre for Image Guidance and Minimally Invasive Therapy (CIGMIT) at the University of Malaya exemplifies how public-private collaborations can facilitate the integration of advanced surgical technologies. By creating a platform for high-quality neurosurgical and spinal care, CIGMIT has significantly improved patient outcomes in Malaysia [37]. Global partnerships have also demonstrated the feasibility of introducing IONM into low-resource settings. In Ghana, Nigeria, and Indonesia, training programs have enabled local neurosurgeons to perform advanced procedures with minimal complications, showing that even complex technologies can thrive in resource-constrained environments [38]. Furthermore, the Duke Neurosurgery Program's twinning partnership with Mulago Hospital in Uganda has strengthened local neurosurgical capabilities while providing specialised training [39]. Similar initiatives in SSAs demonstrate that multidisciplinary collaboration and knowledge exchange can significantly improve surgical outcomes, even in resource-constrained settings [3]. 7. Conclusions IONM has the potential to significantly enhance surgical safety and outcomes in spine surgeries, even in LMICs. Despite challenges such as limited infrastructure, high costs, and workforce shortages, successful implementation of IONM in countries like Brazil, Egypt, and India shows that strategic investments and multidisciplinary collaborations can overcome these barriers. Strengthening healthcare systems, building local capacity, fostering public-private partnerships, and promoting global training initiatives are key to expanding IONM use in resource-limited settings, ultimately reducing disparities in surgical outcomes and improving patient care in LMICs. Declarations Ethical Approval and Consent to participate - Not Applicable Patient Consent for publication - Not Applicable Data availability statement: Not available. Competing interests - None Conflicts of Interest Statement - Authors declare no conflict of interest Funding - None Acknowledgements - None Authors' Contributions; Conceptualization Ideas; W.A.A. Data curation, Writing of initial draft; W.A.A, S.R, A.B.J, P.A.N.B, J.K.T, K.M.M, T.A.R, and O.A. Writing and approval of Final Draft; All authors. References 1. Guzzi G, Ricciuti RA, Della Torre A, Lo Turco E, Lavano A, Longhini F, La Torre D. Intraoperative Neurophysiological Monitoring in Neurosurgery. 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Summary of the methodology Methodology Steps Description Literature Search PubMed, EMBASE, the Cochrane Library, and Scopus. Inclusion Criteria Full-text articles published in English from inception till date Various study designs including descriptive, case-control, cohort, observational, and randomised controlled trials. Studies involving telemedicine in neurosurgery in LMICs. Studies involving both paediatric and adult populations were included. Studies providing raw data. Exclusion Criteria Studies that do not report outcomes. Case reports are excluded. Stand-alone abstracts and unpublished studies. Studies with estimated or modelled numerator or denominator values. Search Terms Keywords include; Intraoperative Neuropsychological Monitoring, Spine Surgeries, Low-and-Middle-Income Countries, low resource settings Additional Search A manual search was conducted to include references from recently published procedure-specific reviews Sample Size Requirement. No strict sample size requirement. Table 2: Overview of types of Intraoperative neurophysiological monitoring Techniques used in Spine Surgeries IONM Technique Description Key Features Advantages Limitations MEPs [2, 12, 13] Generated by electrically stimulating the brain, with responses recorded over the spinal cord or muscles. - Signals from spinal cord (D or I waves) or motor cortex - Detected via electrodes on extremity muscles - Real-time monitoring of corticospinal tract - Greater sensitivity for detecting postoperative deficits - Not suitable for assessing sensory pathways - Requires careful electrode placement and patient cooperation EMG [14] Assesses nerve function integrity during spinal procedures, particularly in nerve manipulation contexts. - Identifies specific nerve disruptions - Records electrical activity from muscles - Protects neural structures during surgery - Immediate feedback on nerve integrity - Limited to muscle response; does not provide direct insight into sensory pathways TMS [2,15] Generates muscle action potentials through brain stimulation; essential for assessing motor system integrity. - Comprises TES and TMS - TES is preferred due to resistance to anaesthesia - Provides information on corticospinal tract functionality - Real-time monitoring - Potential for variability in response due to anaesthesia - TMS is less effective under certain conditions SSEPs [2,3] Assesses the integrity of the dorsal column-medial lemniscus pathway, important for sensory functions. - Elicited by stimulating median or posterior tibial nerves - Recorded in the cortical somatosensory area - High specificity and sensitivity for sensory pathways - Useful in detecting intraoperative nerve damage - Does not assess motor pathways, leading to potential false negatives - Limited in detecting motor injuries Abbreviations: MEP; Motor Evoked Potential, EMG; Electromyography, TMS; Transcranial Magnetic Stimulation, SSEP; Somatosensory-Evoked Potential

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