NASS 2025 RECAP
Gait Analysis as an Emerging Modality for Outcome Measurement in Surgical Spine Patients
Azeem Ahmad, DO
Sinai Hospital of Baltimore Baltimore, MD
Akhil Chhatre, MD
Johns Hopkins Medicine Baltimore, MD
Spinal disorders are a major source of disability worldwide, but assessment of the functional impact of these conditions remains challenging despite advances in imaging techniques, patient-reported outcome measures (PROMs), and surgical options. At the North American Spine Society’s 40th Annual Meeting in Denver, the Interdisciplinary Spine Forum session moderated by Dr. Ram Haddas demonstrated that gait analysis can be a valuable adjunct to traditional assessments of functional impairment in surgical spine patients.
This session brought together surgeons, physical therapists, and biomechanical scientists to advocate for gait analysis as an emerging tool in modern spine care. Speakers presented real-world clinical data demonstrating how gait analysis can identify pathology-specific movement patterns, inform surgical decision-making, guide rehabilitation targets, and quantify postoperative recovery in ways that are not captured by static imaging or PROMs alone. In concert with recent technical advancements, this session outlined a framework for how gait analysis may function as a practical clinical tool with translational relevance for spine care in the coming decade.
Key Takeaways From the Session
- Gait analysis provides objective functional metrics that complement imaging and PROMs
- Distinct spinal pathologies exhibit characteristic gait patterns
- Postoperative gait metrics can validate functional change after surgery and guide rehabilitation
- Emerging technologies in gait analysis are lowering barriers to clinical implementation
- Objective functional data may help frame patient expectations and contextualize recovery
- Ongoing research in the field is exploring whether gait-based metrics can help predict responders versus nonresponders to specific surgical interventions
Why Gait Analysis is Needed as Part of Clinical Practice William Lavelle, MD, MBA
A recurrent theme throughout the session was how traditional assessment techniques fail to capture certain dimensions of functional disability.
Dr. William Lavelle (SUNY Upstate Medical University) provided a surgeon’s perspective, emphasizing that while static imaging remains indispensable in the continuum of care, it cannot capture the dynamic demands placed on the spine during ambulation, balance, and functional transfers. While radiographs can confirm alignment or decompression, they cannot reveal compensatory strategies, dynamic instability, or fatigue-related changes that emerge during routine movement.
Dr. Lavelle also discussed the role and limitations of PROMs such as the Oswestry Disability Index (ODI), Neck Disability Index (NDI), and PROMIS instruments. While these measures offer valuable insight into patient-perceived function, they are inherently influenced by factors such as pain perception, mood, fear avoidance, expectations, and comorbid conditions. As a result, meaningful functional change may not always be fully captured by PROMs or patient satisfaction measures alone.
Using lumbar spinal stenosis (LSS) and cervical spondylotic myelopathy (CSM) as examples, Dr. Lavelle reviewed literature demonstrating that neither imaging severity nor patient-reported functional measures perfectly correlate with objective performance or postoperative outcomes in the majority of patients. In this context, he highlighted gait analysis as a source of quantitative functional parameters that may complement both static imaging and PROMs and thereby help inform surgical decision-making for selected spinal pathologies.
History and Evolution of Gait Analysis Yogi Matharu, DPT
Dr. Yogi Matharu (University of Southern California) used the historical foundation of modern gait analysis to illustrate a number of key principles in the discipline. Beginning with classical observations by Aristotle on joint motion, he traced the field through 19th-century photographic motion studies and into the development of modern biomechanical gait laboratories in the latter half of the 20th century.
Dr. Matharu outlined three primary domains that define contemporary gait analysis. Altogether, these domains provide a comprehensive view of gait by observing how the relationships of joint position, force generation and neuromuscular control vary across the gait cycle:
- Kinematics: describing joint range of motion during ambulation using two- or three-dimensional analysis
- Kinetics: quantifying forces and inertial moments during motion, most commonly through ground reaction force (GRF) measurements
- Muscle activity: as per electromyography of muscular activation during the gait cycle
Dr. Matharu also reviewed the fundamental structure of the gait cycle itself, divided into an approximately 60% stance phase and 40% swing phase component. Within this framework, he discussed how pelvic rotation and center-of-mass displacement influence spinal motion during walking; later in the session, this interrelationship of lower extremity and spinal movement through gait was proposed as a potential contributor to why discrete spinal pathologies tend to produce certain characteristic gait patterns.
Tools for Gait Assessment Andreas Remis, DPT
Building on these foundational concepts, Dr. Andreas Remis (Duke University) discussed the evolution of gait assessment from qualitative observation to objective quantification. He began by acknowledging the longstanding role of clinical pattern recognition – such as wide-based gait in neurogenic claudication, hip circumduction in foot drop, and ataxic patterns in myelopathy – before describing how quantitative gait analysis extends these observations.
By measuring spatiotemporal parameters of gait, joint kinematics, and balance metrics, gait analysis allows clinicians to detect subtle changes in functional performance. Dr. Remis emphasized that this data provides value, not only in tracking postoperative recovery but also in identifying persistent deficits that may be appropriate targets for ongoing rehabilitation. For example, muscular weakness causing limited hip extension or ankle dorsiflexion may persist despite improvement of neurogenic pain after surgical decompression. Identifying these deficits can help physical therapists tailor postoperative rehabilitation with the goal of normalizing gait mechanics and reducing maladaptive movement strategies.
Dr. Remis then reviewed a range of gait analysis technologies, from the gold standard of laboratory marker-driven 3D motion capture systems to emerging clinic-friendly tools. Two technologies saw special emphasis: markerless three-dimensional kinematic systems, which reduce setup time and physical burden for motion-limited patients, as well as wearable inertial measurement units (IMUs), which offer the potential for gait assessment outside the laboratory environment.
Using Gait Analysis to Define Surgical Outcomes Joseph Derian, DPT
Cervical Spondylotic Myelopathy (CSM)
Multiple studies demonstrate characteristic gait patterns for CSM patients when compared with healthy controls, including reduced gait speed, increased step width, prolonged double-support time, and impaired balance. Dr. Derian highlighted a recent systematic review and meta-analysis showing that gait speed consistently improved after surgical decompression when patients were compared with their own preoperative baselines.
Prospective cohort studies tracking both PROMs and gait parameters showed correlations between patient-reported outcomes and gait metrics after surgery. In addition, force-plate studies in postoperative patients showed partial improvement in GRFs related to momentum transfer and shock absorption. While these parameters did not normalize fully compared with healthy controls, the findings provided objective evidence of biomechanical change after decompression surgery.
These observations were highlighted as particularly notable given that surgical intervention for CSM is often framed as disease-stabilizing rather than restorative. The potential for gait analysis to identify measurable improvements in gait mechanics that may not be readily apparent through traditional outcome measures alone – and the role of rehabilitation and therapy targeted specifically towards these changes – is therefore an active area of research within the field.
Lumbar Spinal Stenosis (LSS)
Highlights from the LSS literature as presented by Dr. Derian included multiple sets of linear regression analyses suggesting that improvements in spatiotemporal gait parameters may explain clinically meaningful proportions of ODI variance in patients pre- and post-decompression surgery for symptomatic LSS.
Gait Analysis in Common Degenerative Spinal Pathologies Ram Haddas, PhD, MBA, MEng
With the final presentation, Dr. Haddas (University of Rochester) demonstrated the clinical application of gait analysis through a series of real-world cases spanning CSM, lumbar radiculopathy, neurogenic claudication, and adult degenerative deformity.
Across the CSM cases, postoperative improvements were observed in balance, trunk control, and lower-extremity kinematics, even in certain situations where PROM changes were mixed. For example, one patient complained of worsened postoperative pain despite objective improvements in swing-phase knee flexion, highlighting the complex relationship between objective measures of function and PROMs and the potential for meaningful discrepancies.
Similarly, in lumbar cases, gait analysis demonstrated improvements in abnormal mechanics alongside PROM improvement, while also revealing discrepant findings in certain cases. One patient exhibited relapse of gait speed improvements one year postoperatively despite sustained PROM improvement, raising the question of whether longitudinal gait analysis tracking could emerge as a method to identify subtle deficits before they are reflected in subjective measures such as PROMs.
Finally, Dr. Haddas presented a case of revision of adult degenerative thoracic kyphosis, where functional changes in trunk rotation and postural control captured dynamic changes that correlated with the patient’s improved radiographic alignment.
Conclusion
Gait analysis offers spine surgeons an objective method to assess functional performance that complements traditional imaging and PROMs. By capturing real-world movement patterns, gait analysis provides insight into pathology-specific deficits, compensatory strategies, and the functional impact of surgical intervention. As technological advances continue to reduce barriers to implementation, gait analysis appears to be a promising adjunct to comprehensive spine care, with potential applications in surgical decision-making, rehabilitation planning, and longitudinal assessment of postoperative recovery.
Practical Recommendations and “Next Steps” for Spine Providers
We provide below a set of practical recommendations for spine providers looking to incorporate gait analysis into their ongoing practice:
- Gait analysis may offer value for patients who are borderline candidates for spine surgery, need further optimization of their physical therapy, or are at high risk for progression of their functional deficits.
- Prioritize obtaining gait analysis for CSM and LSS patients meeting the above criteria, especially when their functional deficits do not align with imaging or PROMs.
- Insurance coverage for gait assessment generally depends on documenting an abnormal or unstable gait pattern or fall risk (eg, difficulty walking, unsteadiness, ataxic or spastic gait) or by framing the study as functional benchmarking before and after surgical intervention.
- Comprehensive lab-based gait analysis has limited insurance coverage in this population but may be approved on a case-by-case basis. With that being said, observational (non-laboratory) gait assessment by physical therapists is very commonly covered and may have a role as a proxy when laboratory evaluation is not feasible.
- Finally, continued clinical use and publication of both laboratory- and clinic-based gait assessments (including simple office-based metrics such as gait speed) will be essential to strengthen the evidence base and support broader adoption of gait analysis as a routine adjunct in spine care.
Acknowledgements
The authors thank the session presenters for granting permission to develop this article and for generously sharing their session materials as reference content.