Clinical gait analysis is the gold standard for objectively measuring how people walk enabling better diagnosis, more precise treatment planning, and improved patient outcomes.
Whether you’re setting up a gait lab, upgrading your motion capture system, or evaluating clinical workflows, understanding how gait analysis works and what makes a system effective is critical.
In this guide, you’ll learn:
Looking for a system overview? Explore how Vicon Nexus supports clinical and research gait analysis workflows.
View Buyer's GuideWhat Is Clinical Gait Analysis?
Clinical gait analysis is the quantitative measurement of how a person walks, using motion capture, force plates, and biomechanical modelling to assess movement and guide treatment decisions. Quantitative measurement means the data is expressed in numbers rather than subjective descriptions, making it objective, comparable, and reproducible. Unlike visual observation, it provides repeatable data that clinicians and researchers can rely on across sessions and institutions.
What Does a Clinical Gait Assessment Measure?
A complete assessment includes:
Kinematics: The measurement of joint angles and body segment movement during walking, without reference to the forces that cause them. Kinematic data describes how the body moves.
Kinetics: The measurement of the forces and moments acting on the body during movement, including ground reaction forces and joint moments. Kinetic data explains why the body moves the way it does.
Electromyography (EMG): The recording of electrical activity produced by muscles during contraction. EMG data reveals which muscles are active, when they fire, and whether their timing and intensity are within normal ranges.
Spatio-temporal parameters: Measurements that describe the overall pattern and rhythm of walking, including walking speed, cadence (the number of steps taken per minute), stride length (the distance covered in one complete gait cycle), and step width.
Together, these four data streams create a complete, multi-dimensional picture of human movement.
The Gait Cycle Explained
The gait cycle is one complete walking sequence, from the initial contact of one foot to the same contact of the same foot. All gait data is normalised to this cycle, meaning it is expressed as a percentage of the cycle’s duration rather than in absolute time, enabling consistent comparison across patients, sessions, and walking speeds.
Stance Phase (~60%)
The stance phase is the portion of the gait cycle during which the foot is in contact with the ground, bearing body weight. It accounts for approximately 60% of the gait cycle during normal walking and encompasses initial contact, loading response, mid-stance, terminal stance, and pre-swing.
Swing Phase (~40%)
The swing phase is the portion of the gait cycle during which the foot is off the ground and moving forward in preparation for the next step. It accounts for approximately 40% of the gait cycle and is further divided into initial swing, mid-swing, and terminal swing.
Why Clinical Gait Analysis Matters
Clinical gait analysis provides insights that cannot be captured through observation alone. It helps clinicians answer critical questions:
-
- What is causing abnormal gait?
-
- Is treatment working?
-
- How is a condition progressing?
This leads to better decisions, fewer unnecessary interventions, and improved outcomes.
Clinical Applications of Gait Analysis
Clinical gait analysis is used across multiple domains to support diagnosis, treatment planning, and outcome measurement. Below are the key areas where it delivers the greatest clinical value.
Cerebral Palsy and Paediatrics
Gait analysis plays a central role in the management of children with cerebral palsy (CP), where movement abnormalities are common and often complex. Because CP affects muscle tone, motor control, and skeletal development differently in each patient, objective gait data is essential for distinguishing primary movement problems from compensatory patterns. Clinicians use gait analysis to guide decisions around orthopaedic surgery, botulinum toxin injections, and orthotic prescription and to measure outcomes over time as the child grows.
Neurology
In neurological conditions such as stroke, Parkinson’s disease, and multiple sclerosis (MS), gait analysis provides objective data that clinical observation alone cannot reliably capture. For stroke patients, it helps identify asymmetries and compensatory strategies that inform physiotherapy and rehabilitation planning. In Parkinson’s disease, it can quantify freezing of gait, shuffling, and postural instability. For MS, it supports monitoring of disease progression and the functional impact of fatigue on walking. This longitudinal tracking is particularly valuable for detecting subtle changes between clinical visits.
Orthopaedics
Gait analysis is widely used before and after orthopaedic interventions, including total hip and knee replacement, osteotomy, and spinal surgery. Pre-operatively, it helps confirm the functional impact of a condition and supports surgical decision-making. Post-operatively, it provides objective outcome data measuring whether surgery has restored normal movement patterns and identifying any residual deficits that may require further intervention. This makes it a valuable tool for both clinical audit and patient-specific rehabilitation planning.
Sports Medicine
In sports medicine and performance settings, gait analysis is used to identify biomechanical risk factors associated with injury, such as hip drop, knee valgus, or overstriding, and to develop targeted interventions before injury occurs. It is also used during return-to-sport assessments to confirm that an athlete has recovered functional symmetry following injury. Beyond injury prevention, coaches and performance specialists use gait data to refine running economy and technique in elite athletes.
Prosthetics and Orthotics
For patients using prosthetic limbs or orthotic devices, gait analysis provides detailed information about how a device is affecting movement across the whole body, not just at the point of attachment. It can reveal compensatory strategies, energy inefficiencies, and asymmetries that may not be visible to the naked eye, enabling clinicians and prosthetists to make precise adjustments to alignment, socket fit, and device settings. Over time, repeated assessments can track how well a patient is adapting to a new device and whether further modifications are needed.
How Motion Capture Gait Analysis Works
Motion capture gait analysis tracks three-dimensional movement using infrared cameras and reflective markers, synchronised with force and muscle data. Infrared cameras emit and detect near-infrared light, which is reflected back by small spherical markers placed on the patient’s skin or clothing at specific anatomical landmarks. The system calculates the precise position of each marker in three-dimensional space by triangulating its position across multiple camera views simultaneously.
The 5-Step Workflow
- Marker Placement: Reflective markers are attached to specific anatomical landmarks on the patient’s body — typically bony prominences such as the hip, knee, ankle, and foot — following a standardised protocol such as Plug-in Gait. Consistent and accurate marker placement is critical, as errors at this stage will propagate through all subsequent data.
- System Calibration: Before data capture begins, the motion capture system is calibrated to establish the precise position and orientation of each camera relative to the others, and to define the global coordinate system of the lab. Calibration ensures that marker positions are accurately reconstructed in three-dimensional space and that measurements are consistent across sessions.
- Data Capture: The patient walks along a defined path within the capture volume, the three-dimensional space covered by the camera array, while the system records marker trajectories, ground reaction forces from the force plates, and EMG signals simultaneously. Multiple trials are typically captured to ensure data quality and repeatability.
- Processing and Modelling: The raw captured data is processed using a biomechanical model, such as Plug-in Gait, which uses the marker trajectories to calculate joint angles (kinematics), joint forces and moments (kinetics), and other derived parameters. Modern software platforms automate much of this process, including marker labelling and gap filling, significantly reducing processing time.
- Clinical Reporting: The processed data is reviewed by a clinician or analyst and compiled into a structured report. This typically includes graphical representations of kinematic and kinetic data plotted against normative reference bands, alongside EMG traces, spatio-temporal parameters, and a clinical interpretation. The report forms the basis for treatment decisions, surgical planning, or outcome evaluation.
What You Need for a Clinical Gait Lab Setup
A clinical gait lab combines hardware, software, and environment design to accurately measure movement.
Core Components
- Force plates
- EMG systems
A well-designed lab ensures accurate, repeatable data collection. The physical environment must also be carefully considered with sufficient walkway length, controlled lighting, and a level floor surface to ensure reliable results.
Why Vicon Nexus Is Widely Used in Gait Labs
Vicon Nexus is a leading platform for capturing, processing, and analysing gait data in clinical and research environments.
Key Advantages
- Integrated workflow (capture → analysis → reporting)
- Automated marker labelling and modelling
- Standardised protocols (e.g. Plug-in Gait)
- Compatibility with cameras, force plates, and EMG
This reduces processing time while maintaining clinical-grade accuracy.
Choosing the Right Gait Analysis Motion Capture System
The right gait analysis system depends on your clinical goals, research needs, and available space.
Key Considerations
- Clinical vs research use
- Lab size and capture volume
- Required accuracy and detail
- Workflow efficiency
Choosing the right system ensures long-term scalability and reliability.
Interpreting Clinical Gait Analysis Data
Gait data is interpreted by comparing a patient’s movement patterns against normative datasets, collections of gait data recorded from healthy individuals of similar age, sex, and walking speed, which serve as a reference for what typical movement looks like. Deviations from these norms form the basis of clinical interpretation.
What Clinicians Look For
Deviations from normal movement: Instances where a patient’s joint angles, forces, or muscle activity fall outside the range seen in healthy individuals, indicating a potential impairment or compensation.
Asymmetries: Differences in movement between the left and right sides of the body. Some asymmetry is normal, but significant differences often indicate injury, neurological involvement, or the influence of pain on movement strategy.
Changes over time: Comparisons between assessments conducted at different points in a patient’s care pathway, used to evaluate whether a condition is progressing, stable, or responding to treatment. This longitudinal tracking is one of the most clinically valuable aspects of repeated gait analysis.
Clinical Gait Analysis FAQs
What is clinical gait analysis used for?
Clinical gait analysis is used to objectively measure how a person walks in order to support clinical diagnosis, guide treatment planning, and evaluate outcomes over time. It is applied across a wide range of conditions including cerebral palsy, stroke, Parkinson’s disease, and orthopaedic disorders, as well as in sports medicine and prosthetics. Because it produces quantitative, repeatable data, it enables clinicians to make more informed decisions than visual observation alone allows.
How is gait analysis performed?
Gait analysis is performed by attaching small reflective markers to specific anatomical landmarks on a patient’s body, then asking them to walk along a defined path within a calibrated motion capture environment. Infrared cameras track the movement of these markers in three dimensions, while force plates embedded in the floor measure the loads applied during each step. EMG sensors may also be used to record muscle activity simultaneously. The resulting data is processed using biomechanical modelling software to generate kinematic, kinetic, and spatio-temporal outputs.
What equipment is needed for a gait lab?
A clinical gait lab typically requires motion capture cameras, force plates, EMG systems, video reference cameras, and biomechanical processing software. The physical environment must also be carefully designed, with sufficient walkway length, controlled lighting, and a level floor surface, to ensure accurate and repeatable data collection. The exact configuration will depend on the clinical or research application, the patient population, and the volume of assessments being conducted.
What is the difference between clinical and research gait analysis?
Clinical gait analysis is focused on informing individual patient care, answering specific diagnostic or treatment questions within a defined workflow. Research gait analysis typically involves larger subject groups, more experimental protocols, and a greater emphasis on data flexibility and customisation. In practice, many labs serve both purposes, and modern platforms such as Vicon Nexus are designed to support both clinical and research workflows within the same environment.
How long does a clinical gait analysis assessment take?
A full clinical gait analysis assessment typically takes between one and three hours, depending on the complexity of the patient’s condition and the number of trials being captured. This includes time for marker placement, system calibration, data capture, and initial review. Data processing and report generation may take additional time, depending on the degree of automation within the software being used.
What is the Plug-in Gait model?
Plug-in Gait is a widely used biomechanical model that calculates joint angles, moments, and powers from motion capture data using a standardised marker set. It is one of the most established protocols in clinical gait analysis and is supported natively within Vicon Nexus. Because it is standardised, it allows data to be compared across patients, sessions, and institutions, making it particularly valuable for multisite research and long-term outcome tracking.
How accurate is motion capture gait analysis?
Modern motion capture systems used in clinical gait labs are capable of sub-millimetre marker tracking accuracy under controlled conditions. In practice, measurement accuracy is influenced by factors including marker placement consistency, system calibration, lab environment, and the biomechanical model being applied. Standardised protocols and experienced operators are key to ensuring that data is both accurate and reproducible across sessions.
What conditions can gait analysis help diagnose or manage?
Gait analysis is used in the assessment and management of a broad range of conditions, including cerebral palsy, stroke, Parkinson’s disease, multiple sclerosis, osteoarthritis, scoliosis, limb length discrepancy, and lower limb injuries. It is also used to evaluate patients following joint replacement, spinal surgery, or amputation. In each case, the value lies in its ability to provide objective, quantitative data that complements clinical examination and imaging.
Can gait analysis be used with children?
Yes. Gait analysis is routinely performed with paediatric patients, particularly those with cerebral palsy and other neurodevelopmental conditions. Paediatric assessments follow the same core principles as adult assessments, though marker sets and normative reference data are adjusted for age and body size. Experienced labs will have established protocols for working with younger or less cooperative patients to ensure data quality.
What is a normative dataset in gait analysis?
A normative dataset is a collection of gait data recorded from healthy individuals, typically matched for age, sex, and walking speed that serves as a reference for clinical interpretation. When a patient’s data is compared against a normative dataset, deviations from typical movement patterns become visible and quantifiable. This comparison is fundamental to clinical reporting and helps clinicians identify which aspects of a patient’s gait are outside the expected range.
Explore Clinical Gait Analysis Solutions
If you’re planning a gait lab or upgrading your current setup, choosing the right system is critical.
With integrated hardware and software, Vicon Nexus supports:
- Clinical workflows
- Research applications
- Scalable lab environments
Next steps:
- Request a system overview
- Speak to a gait analysis specialist
- Explore hardware and software options