Routine health assessments will typically involve measuring heart rate, blood pressure, blood oxygen saturation, and body weight. Current medications are reviewed, and patients are asked if they’ve experienced any changes in their health lately. A brief assessment of balance and muscle strength follows, but what about gait? Most people know their blood pressure or weight, but few can accurately describe the way they walk.
The five commonly known vital signs – temperature, heart rate, respiratory rate, blood pressure, and oxygen saturation – provide critical information in assessing and predicting a patient’s health status. But they are not able to provide visibility into the potential physical and psychological impacts surrounding mobility, fall risk, and need for rehabilitation. Routine gait assessment, however, can fill this gap. A growing body of evidence supports the notion that changes in specific gait parameters can be used as a functional ‘6th vital sign’ to help indicate a person’s functional status, the likelihood of falls, and potential discharge location. No two individuals walk exactly the same, likening gait patterns to fingerprints. From gross motor delays in children to fall risk in older adults, gait assessment, when leveraged effectively, offers unprecedented insight that can lead to earlier and more precise intervention.
The most commonly observed gait parameter: gait speed
Designated the 6th vital sign, and among the most popular gait parameters in current literature and clinical use is gait speed. With the ability to help predict functional ability and health status, research demonstrates that each reduction in gait speed by only 0.1 m/s correlates with an 8% increase in the risk of cardiovascular disease and a 12% increase in the risk of elderly mortality. It is already being used to reflect frailty status – identifying increased risks of adverse events such as falls, prolonged hospital stays, and overall functional decline. Assessing a complex activity such as walking and walking speed can shed light on mobility and how individuals interact and navigate their environment. Without this information, there are missing pieces to the puzzle and missed opportunities for proactive intervention, early diagnoses, and more thorough patient care.
Gait speed is only one of many valuable parameters
What about the spatiotemporal parameters of gait? These parameters are often not assessed without highly sophisticated – and expensive – equipment. Yet, research shows that assessing multiple parameters of gait can give not only a better understanding of functional mobility and potential for musculoskeletal conditions at the impairment level but can also aid in the early detection of falls, fear of falling, hospitalization, disease processes, and mortality.
Existing evidence shows a correlation between changes in various gait parameters and an increased risk for falls. Specifically, a decline in gait speed coupled with an increase in gait variability (i.e. stride length, step length, and double support time) may increase the risk of falls. A slower walk with more variation might be less safe and require intervention. While it may be seemingly obvious, these parameters are not often captured or evaluated in a clinical setting, making it more difficult to identify objective changes of status or risk and address these concerns quickly.
Changes in gross motor function, specifically gait variability, can often be an early indicator of other neurodegenerative diseases, such as Alzheimer’s and Parkinson’s, which often affect cognition. In particular, both Alzheimer’s and Parkinson’s disease progressions are accompanied by increased stride variability. Observing changes in gait may indicate the progression of the disease and alert the medical team for further escalation and intervention. Furthermore, a study published in the Journal of Alzheimer’s Disease suggests that changes in gait can precede changes in cognitive decline in patients who develop dementia. The authors discuss the applications of routine gait analysis as a viable option to aid in the early detection of cognitive decline and dementia.
Assessing gait sporadically and observationally isn’t cutting it
Gait speed is traditionally measured with a stopwatch. It’s a straightforward assessment, and it does yield objective results. But its drawback is that it’s limited to in-person assessments and requires the supervision of a trained professional. Additionally, spatiotemporal gait parameters require capital-intensive sophisticated technology that is likely not accessible by many clinicians. As such, therapists are forced to rely more on observational analysis to describe such characteristics – limiting objectivity to a small snapshot in time when the patient is in the clinic.
To truly capture and leverage the health insight gait offers, there must be a baseline with continuous monitoring. Thankfully, advancements in gait analysis smartphone technology now make it possible to easily establish baselines for multiple key gait parameters and observe changes over time. This enables clinicians to monitor gait in a patient’s typical environment comparable to how one would monitor heart rate or blood glucose levels using portable at-home devices that send real-time data back to the provider for a more complete picture of health. And with easy-to-use technology now available, continuous gait assessment monitoring can be easily integrated into a physical therapist’s repertoire.
Gait as the vital sign for physical therapists
As movement experts, physical therapists are uniquely positioned to be the experts at monitoring gait in the way that cardiologists are the experts when monitoring blood pressure and heart rate. While healthcare providers of different fields are trained to measure and interpret these vital signs, cardiologists are trained to make advanced clinical decisions. Gait assessment should be utilized in the same way. Given adequate training and the proper technology, gait and motion analysis can be integrated into routine physical evaluations, neurological exams, cardiovascular assessments, prosthetics management, and the list goes on. Physical therapists are healthcare professionals trained to optimize health through movement and a critical component of their evaluation is assessing gait and mobility.
Furthermore, this opens up the conversation surrounding the role of physical therapists in primary healthcare and the benefits of preventative visits with physical therapists to identify movement disorders early in disease processes and prior to future illness or injury.
Monitoring gait can inspire a healthier population
Monitoring gait transcends the individual patient and has the potential to inspire a much healthier population. It has predictable measures that are both reliable and valid. Coupled with accessible technology that can seamlessly take in various inputs to analyze this complex functional activity, patients can become more informed of their motion health and functional status – and take appropriate action toward a lifestyle filled with more movement.
“Walking is man’s best medicine!” – Hippocrates
Perhaps the world has overlooked such a simple principle for far too long. If movement is medicine, and research clearly supports this sentiment, why is motion health often treated reactively instead of proactively? It’s time to leverage gait as the 6th vital sign to better understand overall health, identify disease processes earlier, and keep people moving confidently throughout all walks of life.
About Alaina Victoria
Alaina Victoria, PT, DPT, is a Clinical Content Manager for OneStep, and a doctor of Physical Therapy with a passion for digital health technology. Her prior experience includes working within the rehabilitation and orthopedic settings as both a permanent and travel therapist. She is a member of the American Physical Therapy Association (APTA) including the APTA Academy of Geriatrics Physical Therapy, APTA Frontiers in Rehabilitation, Science and Technology Council, and the APTA Health Promotion and Wellness Council.