Invited Review

Novel Concepts in Clinical Guideline Development in Spine Surgery

Kai-Uwe Lewandrowski, MD

Center for Advanced Spine Care of Southern Arizona and Surgical Institute of Tucson Tucson, AZ

Abduljabbar Alhammoud, MD

Assistant Professor, University of Arizona College of Medicine Tucson, AZ

Morgan P. Lorio, MD, FACS

Advanced Orthopedics Altamonte Springs, FL

Introduction

Clinical guidelines are based on best research evidence, and hopefully, help guide enlightened therapeutic decision making, in the context of clinical experience and patient preferences. (Figure 1) The increasing complexity of procedures and rapid technological advancement require updates of current clinical guidelines in spine surgery to assess their significance, formulate therapeutic recommendations, and suggest potential future directions. The primary goal of clinical guidelines is to optimize patient outcomes and ensure the consistent delivery of high-quality care.1 Specifically, the guidelines in spine surgery:

1. Summarize vast amounts of research data into actionable recommendations, making it easier for clinicians to stay updated with the latest evidence.

2. Provide a benchmark for quality, facilitating peer reviews and performance evaluation.

3. Reduce the variability in patient outcomes by standardizing care across institutions and regions.

Figure 1. The term "evidence-based medicine" (EBM), introduced by Dr. Gordon Guyatt at McMaster University and further developed by his adviser Dr. David Sackett, emphasizes the integration of best research evidence, clinical expertise, and patient values. 2,3,4,5

The North American Spine Society (NASS) has published several clinical guidelines to advance quality spine care through education, research, and advocacy to reflect the latest research and clinical best practices. As of April 2023, NASS has published clinical guidelines on important topics in spine surgery and has several others in development (Table 1).

Table 1. Clinical Guideline Development of the North American Spine Society

These guidelines are not only intended for spine specialists but also for primary care providers, patients, policymakers, and payers. They are aimed at informing all stakeholders about the most current and agreed-upon approaches to diagnosis, treatment, and management of various spinal conditions. Most of these guidelines follow a scripted outline regarding diagnosis and imaging, conservative management, surgical indications, choice of procedure and postoperative care. They recommend appropriate imaging (X-rays, MRI, CT scans) based on the patient's clinical presentation. For instance, an MRI is usually indicated for patients with radicular pain that does not improve with conservative measures. Typically, prior to a surgical recommendation, a trial of conservative treatments like physical therapy, medication, or spinal injections is suggested, unless the patient has severe or progressive neurological deficits. Guidelines are also intended to help surgeons decide between procedures like discectomy, fusion, or disc replacement. Recommendations also cover aspects such as postoperative pain management, rehabilitation, and management of complications.

Limitations and Challenges in Spine Surgery

Critics might argue that standardizing care and associated outcomes would simplify complex clinical decisions.16 Each patient is unique, and guidelines should not replace individual clinical judgment. There may also be biases involved with guidelines development, such as hindsight bias, in which researchers unknowingly confirm preconceived notions of clinical outcomes with specific surgical procedures, especially when the outcome to be studied is already known.17,18 Guideline development may also be influenced by industry funding or other conflicts of interest, and recommendations might be skewed.19,20 The biggest challenge with clinical guideline development lies in the background research involved in their creation. The painstaking and time-consuming clinical study of innovations may take years. Therefore, clinical guidelines may not be able to keep up with the rapid pace of innovation and technology advancements since their creation involves a retrospective analysis and traditionally precludes forward looking analysis. Frequent updates are ideal but largely impractical. In spine surgery, clinical evidence and guideline development face a range of challenges due to the complexity of spinal disorders and the diversity of potential treatments.21,22 Clinical studies often involve issues with standardization of surgical techniques and difficulty in controlling for confounding variables, such as the surgeon's skill and patient selection criteria. Additionally, there is significant variability in patient anatomy and the natural history of spinal diseases, which limits what may adversely influence, generalizability (Table 2). Recognizing these challenges, the North American Spine Society is continually working to refine the process of clinical guideline development to ensure that the recommendations are evidence-based, relevant, and able to be effectively implemented in clinical practice. Assembling evidence into coherent and widely applicable guidelines demands meticulous evaluation of subjective patient-reported outcomes—often influenced by expectations and psychological factors of utilization and efficacy—and iterative consensus-building among multidisciplinary experts to ensure that recommendations are evidence-based and practically applicable in a clinical setting. On its face, this process appears complex and often fails to engage the practicing spine surgeon.

Table 2. Challenges in Clinical Guideline Development in Spine Surgery

Traditional Clinical Guideline Development

In the face of rapidly changing medical knowledge and practice, traditional clinical guidelines development is evolving into more dynamic and technologically advanced approaches. It is a systematic process that involves several key steps to ensure that the guidelines are evidence-based, clinically relevant, and up to date. Guidelines play a critical role in standardizing care, improving patient outcomes, and providing a benchmark for the quality of care. The typical stages involved in traditional clinical guideline development are summarized in Table 3. This traditional approach to clinical guideline developmentis resource intensive. It requires considerable time, expertise, and funding. Moreover, conflicts of interest must be managed to prevent biased recommendations. Keeping them current can be quite challenging since rapid advancements in medicine can outpace the update cycle of guidelines. The latter problem may cause practitioners not to implement or adhere to the guidelines in clinical practice particularly if they are not motivated by a perceived lag between technology advances and adjustments in medical necessity criteria for intervention to prompt payer authorization.

Rapid Innovation Cycle and Clinical Evidence

The industry-driven nature of spine surgery innovation is largely fueled by the active involvement of medical device companies in the development and promotion of new technologies and surgical techniques. This sector is marked by rapid advancements in materials and instrumentation, such as novel spinal implants, robotics, and minimally invasive tools, aimed at improving patient outcomes and recovery times.23 However, this brisk pace of innovation can sometimes prioritize market interests and device proliferation over extensive clinical validation. The close collaboration between surgeons and industry can lead to enthusiastic early adoption of cutting-edge technologies with limited high-quality evidence to support their superiority over existing methods. This environment creates a dynamic where financial incentives and the promise of technological breakthroughs may outstrip the slower, more methodical process of evidence-based guideline development. Consequently, there is a need to navigate the potential benefits of new surgical options in the context of the imperative for rigorous, independent clinical trials to validate their safety and efficacy.

Table 3. Typical Stages Involved In Traditional Clinical Guideline Development

Patient Registries

Patient registries in spine surgery are databases in which information is systematically collected about individuals who have undergone spinal procedures. Registries have been set up to compare novel to established surgeries, but have suffered from several limitations that have hindered their ability to produce high-grade evidence.24-26 For example, patient registries typically collect data in a non-randomized fashion. Thus, they are susceptible to selection bias, as patients are not randomly assigned to treatment groups. Registries often rely on voluntary data submission from multiple centers with different levels of detail and accuracy in data recording. This variability has led to inconsistent data quality and difficulty drawing generalizable conclusions. Without the strict controls of a clinical trial, patient registries may include a wide range of confounding variables, such as variations in surgical technique, surgeon experience, and patient characteristics, which can obscure the effects of the surgery itself. The heterogeneity of treatments and patient populations is another significant problem with registries. Spine surgery encompasses a diverse array of procedures and patient diagnoses. Registries that lump different types of surgeries and patient groups together may not be able to provide specific enough insights into particular interventions or populations. Incomplete capture of outcomes and utilization is often problematic because of a lack of long-term follow-up,27 making it difficult to assess the sustainability of treatment effects or long-term complications.28 Spine surgery outcomes are multifaceted, including pain relief, functional status, reoperation rates, and quality of life. Registries may not capture all relevant outcomes or may rely on patient self-reporting, which is subject to bias.28 Additionally, there can be underreporting of negative outcomes or complications for various reasons, including reporting bias or inconsistencies in how complications are defined and recorded across different reporting sites.29 Funding and sponsorship issues may also be relevant. If industry stakeholders fund a registry, there may be concerns about the impartiality of the data collected, particularly if adverse outcomes for specific devices or procedures are downplayed. Ethical and privacy concerns may also exist. Theoretically, these limitations could be overcome by designing registries with prospective enrollment, standardized data collection methods, adequate follow-up, and statistical methods to adjust for confounding variables. In reality, registries traditionally had little traction in spine surgery because they were impractical or failed to deliver the desired clinical evidence rapidly.

The Glass Ceiling Effect and the Hierarchy of Clinical Evidence

High-grade randomized prospective clinical trials (RCTs) are considered the gold standard for evidence in medicine due to their ability to minimize bias. However, in spine surgery, conducting RCTs is fraught with challenges. The most relevant confounding factor that is impossible to randomize is the surgeon's skill level. Double-blinding is also impractical since both patients and surgeons know the procedure performed. Therefore, most RCTs in spine surgery have turned into well-controlled observation cohort studies with an intent-to-treat analysis. This phenomenon has been coined the “glass ceiling” effect in outcome research in spine surgery.30,31 It is described in detail, along with a newly updated pyramid of clinical evidence examination, in another article in this SpineLine issue (need link).32 In essence, Grade A clinical evidence can be developed with observational studies as long as reported outcomes are consistent and reproducible. Such was the case with arthroscopic knee surgery for degenerative osteoarthrosis or meniscal tears,32,33 vertebroplasty for osteoporotic vertebral fractures34 and subacromial decompression for shoulder impingement.35 None of these procedures did withstand the scrutiny of sham-controlled randomized trials16yet they are well-established standards today. Further, traditional systematic review and meta-analysis of extracted and processed data have been at the top of the clinical evidence pyramid.33-35 The American Medical Association (AMA) supports this concept to this day.36 A new concept, termed Living Clinical Guidelines, has been defined. It implies rapid updates and a different application of systematic review and meta-analysis in clinical evidence grading. Rather than using systematic review and meta-analysis as the dogma of highest available clinical evidence, they are used as a mere examination method of the available clinical evidence in a more modern interpretation of the clinical evidence pyramid.37

Living Clinical Guidelines

The living clinical guidelines concept is an innovative approach to clinical practice recommendations that aims at keeping guidelines current by adapting to the latest evidence without the delays inherent in traditional guideline updating processes.38 In spine surgery, this concept is particularly valuable due to the rapid pace of technological advancement and the continuous emergence of new technology and associated clinical data. This process to rapidly assess the clinical evidence of new emerging technologies depends on real-time updates where existing recommendations may be altered or new ones added. Surgeons, patients, and other stakeholders should be engaged via digital surveys to poll their opinions on clinical outcomes with new technologies and to better understand the psychometric motivators of clinical decision-making as described below. “On-the-ground” level engagement is critical to update the guidelines to ensure they remain relevant and practical. Guidelines may be enhanced by artificial intelligence (AI) and rapid and efficient computational analysis of vast amounts of “Big Data” research to further investigate the safety and efficacy of new technology on more granular level. Policy statements for medical coverage should be issued based on ongoing guideline updates. Spine societies have issued several such policy statements to facilitate negotiations with insurance companies or government health care systems. They outline a new technology’s surgery indications and recommended coverage for payment based on comprehensive analysis of clinical efficacy, safety, and cost-effectiveness. These policy statements are crucial for both patients and health care providers as they determine accessibility and reimbursement. Integration of modern digital platforms may facilitate the ongoing process by disseminating updates promptly. Societies representing spine surgeons should allocate resources to fund this ongoing commitment.

Tapping Into Spine Surgeons’ Clinical Experience

Spine surgeons’ clinical decision-making has its foundation in postgraduate training, traditionally formulated clinical guidelines, and, most importantly, clinical experience. Implementing protocol change due to new high-grade clinical evidence has been characterized as slow because of study distortions by strict patient selection and randomization criteria that cannot be easily replicated in an individual practice. Surgeons may be eager to consume the new information but often return to their established practice protocols because they do not believe the information presented on a new technology applies to their patients. This common scenario creates a disconnect between the formalized clinical evidence study by professional medical associations, payers, and governmental health agencies and the problems encountered in on-the-ground clinical decision-making, including payor authorization for surgery, and reimbursement. Tapping into spine surgeons' clinical experience using surveys analyzed with the Rasch model can significantly enhance the development of living clinical guidelines. The Rasch model is a psychometric tool used for constructing and analyzing surveys statistically after logarithmic transformation, particularly in the health sciences, ensuring that the data derived from these surveys are reliable and valid on a linear scale.39-47 This partial agreement analysis methodology has several benefits in rapid guideline development listed in Table 4.

Table 4. Survey-Based Partial Agreement Rasch Analysis In Rapid Clinical Guideline Development

Using the Rasch model to leverage the clinical experience of spine surgeons may be a valuable way to rapidly measure surgeons' experience with specific procedures and implants in addition to traditional clinical guideline development. The psychometric measurement approach of surgeons' level of endorsement for proposed protocol changes (Figure 2) may provide additional information needed to create living clinical guidelines that are not only evidence-based but also grounded in the day-to-day practical realities of patient care.

Figure 2. Shown are exemplary plots of a polytomous Rasch partial agreement analysis to assess spine surgeons’ level of endorsement of five test items (patient outcomes, comfort with the procedure, instruments, patient factors, and rehabilitation) regarding a commonly performed lumbar decompression surgery. Shown is the resulting Wright plot on the left. The blue horizontal bars correspond to the responding surgeons’ latent traits written in logits (log odds) as estimates of true intervals of item difficulty and surgeon ability. The surgeons represented by horizontal bars at the top indicated a higher level of endorsement for the individual test components (positive logits) than those on the bottom (negative logits). On the right, the higher-level endorsement items are listed at the top versus the easier to agree on items on the bottom. Each item may be visually inspected using its item characteristic curve (ICC) to assess the alignment between anticipated and actual values. An exemplary ICC plot is displayed in the top right graph for comfort and familiarity with the tested spine surgery. The dots graphically denote the average response of individuals in each class interval (CI), while the solid blue curve represents the expected values predicted by the Rasch model. The corresponding Person Item Map (bottom right) shows the logarithmically transformed person and item positions on a unified continuum using the logit measurement unit, transitioning ordinal data to equal-interval data. This method charts both person and item positions (in logits) along the x-axis. Within Rasch modeling, these values are labeled as "locations" rather than "scores." A surgeon's logit location indicates their natural log odds of agreement with a series of items. Individuals with pronounced adherence to the considered attitude affirm items favorably, positioning them further to the right on the scale. The solid dots indicate the mean person location scores. The items "comfort level with the exemplary lumbar decompression procedure", and "patient-related factors" were the easiest to agree on. These items also had the smallest spread of logit locations. The most challenging item to agree on was "clinical outcomes", and "postoperative rehabilitation”. This type of Rasch analysis can expose more intense partial agreement with a test item—in this case a commonly performed lumbar spinal decompression procedure. The person item maps also illustrates that items were reasonably well distributed. However, some surgeons could not be measured as reliably as the majority by this set of items, indicating the test items were either too intense or not intense enough for them. The red circles highlight these areas. The analysis also showed disordered thresholds of endorsement for the five test items shown in this exemplary plot, suggesting that surgeons had difficulty consistently discriminating between response categories ranging from strongly disagree (1), disagree (2), agree (3), to strongly agree (4)—a problem observed when there are too many response options (all disordered items shown in red). Examining the order and location of these test items reveals an uneven distribution of the ranked order of item difficulties or intensities along the logit continuum illustrating the true complexity of real-world surgical decision-making—data that should be integrated into traditionally developed clinical guidelines to keep them up-to-date.

Conclusions

In the future, guidelines should be made more dynamic by incorporating real-world data and ensuring they are adaptable to individual patient needs. Additionally, as personalized care models gain prominence, there is a push to involve patients more actively in the guideline development process. Living guidelines will continue to evolve as the field advances, reflecting the synthesis of new research, technological innovation, and collective wisdom of the spine surgery community. Regularly engaging the spinal surgeon as a critical stakeholder with society-sponsored research surveys is the key element in the successful implementation of a living guideline. It also may improve a professional society’s relevance with their membership as spine surgery practitioners have confidence that the clinical recommendations they follow are based on the latest and most robust evidence, allowing for patient care that is both cutting-edge and deeply rooted in the current scientific understanding.

References

Author Disclosures

KU Lewandrowski: Nothing to disclose

A Alhammoud: Nothing to disclose

MP Lorio: Nothing to disclose