Patients living with chronic neck or back pain caused by degenerative spinal disease can transform their lives with spinal fusion surgery. The procedure relieves years of pain, restores spinal stability, and helps people return to work and the activities they enjoy. Spinal fusion, however, ranks among the most complex orthopedic surgeries, and its success depends on much more than surgical skill. Decades of research and carefully designed clinical trials drive every good outcome, providing evidence that guides surgeons toward the best procedures, identifies patients most likely to benefit, and reveals how new technologies can improve results and reduce complications. As spinal fusion surgery evolves, clinical trials, especially Level 1 randomized clinical studies, play a leading role in shaping patient care and establishing new standards to improve outcomes.
The scale of spinal fusion
Although many view spinal fusion as a highly specialized operation, it ranks among the most common major surgeries in the US, with surgeons performing more than 300,000 cervical and lumbar spine procedures each year.
A 2025 analysis of the PearlDiver all-payer claims database identified 1.2 million cervical spine surgeries performed between 2010 and 2022. Surgeons performed anterior cervical discectomy and fusion (ACDF) most often, accounting for 61.6% of all cases (774,913 surgeries), followed by decompression-only procedures (21.1%), posterior cervical instrumented fusion (14.0%), and cervical disc arthroplasty (3.4%). Although ACDF continues to provide excellent clinical outcomes and remains a safe and effective treatment for many patients, surgical practice is changing. The annual number of ACDF procedures declined by nearly 15%, while the use of alternative procedures, such as posterior cervical foraminotomy and cervical disc arthroplasty, has increased. One reason for the shift is that achieving successful fusion becomes more difficult as surgical complexity increases, particularly when multiple vertebral levels require treatment. Although ACDF remains highly effective, its limitations become more apparent in these complex cases. As a result, the growing cervical spine surgery market is expanding beyond ACDF alone, with increasing use of posterior and motion-preserving procedures that complement or, in some cases, replace traditional fusion. Similar trends appear in lumbar spine surgery. A 2026 cross-sectional study analyzed more than five million lumbar fusion admissions in the United States between 2002 and 2023. The study found that the age-adjusted rate of inpatient lumbar fusion increased from 60.1 per 100,000 population in 2002 (148,823 admissions) to 80.0 per 100,000 in 2023 (273,235 admissions). Surgeons increasingly used more complex procedures, especially combined anterior-posterior fusion techniques. Because spinal fusion is performed so frequently, even modest failure rates can create a substantial clinical and economic burden. Despite its widespread use, our understanding of outcomes after multilevel fusion remains limited, as much of the available evidence comes from a relatively small number of studies and relatively short follow-up times and qualitative measures. This highlights the need for high-quality clinical trials that provide the strongest evidence for evaluating treatment effectiveness.
Fusion grows more challenging
Patients undergoing single-level fusion surgery generally have excellent outcomes. Fusion rates exceeding 90% are commonly achieved, and most patients experience significant improvements in pain, neurological function, and quality of life. However, outcomes are less predictable in patients requiring multilevel fusion, where three adjacent spinal segments are treated. In these more complex cases, reported fusion rates fell below 30%. Failure of the bones to fuse, known as pseudarthrosis (nonunion), may lead to persistent neck pain, worsening neurological symptoms, swallowing or voice problems and reduced function, and many patients also require revision surgeries. These challenges have increased interest in alternative surgical approaches. For example, supplementing posterior cervical fusion (PCF) has been shown to improve fusion rates in high-risk patients. However, most multilevel cervical fusions in the United States continue to be performed using ACDF alone because the addition of a posterior procedure increases operative time and is generally associated with longer hospital stays as well as more morbidity and pain.
The patient experience
Recovering from spinal fusion takes time. Most patients need weeks to months of limited activity, physical therapy, and rehabilitation before returning to work and everyday life. During recovery, the biggest uncertainty is whether the bones will heal together successfully. When fusion is successful, patients often experience less pain, improved mobility, and a better quality of life. When it is not, they may continue to have pain, nerve symptoms, and limited function, and some require another surgery with a longer recovery. Today’s clinical research looks beyond radiographic evidence (X-rays) to measure what matters most to patients. In addition to confirming successful fusion, studies assess pain, physical function, and quality of life using patient-reported outcome measures, such as the Neck Disability Index. Achieving fusion on the first attempt is important. Failed fusion can lead to more complex revision surgeries, higher healthcare costs, and additional problems in nearby spinal segments over time. By improving the chances of a successful first surgery, better treatments can reduce complications, lower healthcare costs, and help patients return to healthier, more active lives.
Emerging clinical trial evidence
Here, clinical trials play a critical role. Rather than simply serving as a regulatory requirement, they provide the strongest evidence for improving medical care. Unlike retrospective studies that analyze existing patient records, Level 1 randomized clinical trials assign patients to treatment groups before surgery and evaluate outcomes using standardized and rigorous qualitative methods. This design minimizes bias and provides greater confidence that differences in outcomes are truly attributable to the treatments being studied. A recent example is the FUSE study, a randomized FDA trial in patients undergoing three-level cervical fusion. It compared standard three-level ACDF with combined anterior-posterior approach (ACDF plus a tissue-sparing posterior procedure, called CCF). The results were striking:
- At 12 months, about 64% of the combined-approach patients achieved fusion, versus 19% with ACDF alone with more than a threefold difference.
- At 24 months, fewer than 2% of combined-approach patients needed revision surgery, compared with 28% of those treated with ACDF alone.
- Complications were lower with the combined approach, and hospital stays were similar despite slightly longer operating time.
Procedure-related adverse events were significantly lower in the CCF group, and hospital length of stay remained similar despite a modest increase in operating time. A single trial does not answer every question about cervical fusion, and, like any industry-sponsored study, its findings should be interpreted carefully, considering the funding source, study design, and the need for independent confirmation. However, it provides high-quality, peer-reviewed evidence by directly comparing a new treatment with the long-standing standard of care and following both radiographic and clinical outcomes over two years.
Clinical data’s wider impact
The influence of clinical trials extends well beyond the operating room. Regulatory agencies rely on robust clinical evidence when evaluating new medical devices. Professional medical societies use published evidence to develop treatment guidelines that help physicians make informed decisions. Hospitals and healthcare networks increasingly consider comparative effectiveness data, rather than familiarity or cost alone, when making procurement decisions. Insurance providers and government healthcare programs use clinical evidence when setting reimbursement policy. A growing emphasis on evidence-based medicine helps ensure that innovations are adopted because they improve patient care, not simply because they introduce new technology. The future of spinal fusion will be shaped not only by advances in implants and surgical techniques but by the strength of the evidence supporting them. Every well-designed clinical trial helps identify safer, more effective ways to improve patient outcomes and reduce the need for future revision surgeries. High-quality studies such as FUSE have an impact that extends well beyond the operating room, informing clinical practice guidelines, influencing insurance coverage and government reimbursement policies, and accelerating the adoption of evidence-based innovations. By generating high-quality Level I evidence, clinical trials help transform promising surgical advances into proven standards of care, leading to safer and more effective patient care.
Matt Jenkins
www.providencemt.com
Matt Jenkins, MS, BME, is the Vice President of Clinical Affairs at Providence Medical Technology, where he directs clinical development and medical evidence strategy across the company’s spine portfolio. With over 20 years of progressive leadership experience in the medical device and combination product industries, Matt specializes in shaping enterprise clinical strategy, leading PMA and 510(k) programs, and integrating real-world evidence with regulatory and commercial objectives. His prior roles include serving as Director of Medical Affairs Operations at Roche Tissue Diagnostics (Ventana) and Senior Clinical Studies Engineer at BIOTRONIK. Matt holds a Master of Science in Biomedical Engineering from the University of Connecticut, as well as bachelor’s degrees in Biochemistry and Economics from the University of Arizona.
