How do PKMAS software and Zeno Walkway compare to other gait analysis systems?

Zeno Walkway System (Pressure Mat)

System makeup

A rollout pressurized walkway with cabling to connect to a computer.

System Setup

Our gait and balance assessment system can be set up in a matter of minutes. The Zeno Walkway can be laid out permanently or be set up and dismantled for each use. Each time the system is set up, there is a required hardware integrity check that takes a few seconds, to ensure proper hardware function.

Patient/Subject Setup

There is no setup of the patient/subject required. Nothing is placed on the body of the patient/subject.

Collection Space – The system can be portable or set up in a lab space. The Zeno Walkway System can turn just about any flat, hard surface into a gait lab.

Sample Size

Dependent on the size of the mat. Data can be collected continuously so the patient/subject can walk up and down the Zeno Walkway as many times as is required to collect appropriate sample size.

Data Processing Time

The majority of trials will be processed in less than 1 minute. Some difficult trials may take up to 5 minutes to process.

Data output

Temporal-Spatial Gait, Center of Pressure trajectories, Relative Pressure, COMe

Camera-Based Gait Analysis System

System makeup

A group of cameras, generally 6-16 with cabling to connect with a collection box and then to a computer. These systems are most often coupled with force plates for gait analysis.

System Setup

Cameras need to be mounted on tripods or onto walls. These need to be placed precisely to create a continuous capture volume. If force plates are used, they need to be placed within the floor in the center of the capture volume.

Once the cameras are set, they need to be calibrated using a dynamic calibration. This takes a few minutes and would ideally be done at least daily.

Patient/Subject Setup

The subject needs to have passive, reflective markers attached or placed on them. This can vary in time from about 5-20 minutes depending on the marker set. Once the markers are placed, a calibration trial must be calculated with the subject in the center of the capture volume. This collection can take less than a minute.

Collection Space

Most commonly, a room is dedicated for the camera system as a gait lab. These labs tend to be permanent.

Sample Size/Collection Time

This is dependent on the number of cameras and force plates. It is possible to capture a few strides per pass in a common lab space to calculate kinematics. Collecting data for kinetics takes more time due to the requirement for complete footfalls on force plates and generally a limited number of force plates in the lab.

Data Processing Time

Time can vary depending on the presence of force plates, use of assistive devices, and quality of the gait. With force plates labeling foot contacts and foot offs automatically, processing can take less than a minute per pass. Processing can take over 10 minutes per pass for difficult walks. If there are no force plates, foot contacts need to be manually labeled based on marker motion.

Data Output

Joint Kinematics. If coupled with a force plate, joint kinetics. Can also calculate temporal –spatial parameters for few stances on the forceplate and extrapolated for the rest of the capture area.

IMU-based Gait Analysis System

System Makeup

Multiple IMUs, a charging port, a data receiver or a data logger and a computer.

System Setup

The accelerometers need to be set to stream or store data. Sensors can store data to be downloaded later or stream data to a computer. Confirmation that the sensors are all streaming properly is necessary with synchronization between sensors.

Patient/Subject Setup

Accelerometers need to be placed appropriately. This can take a couple of minutes.

Collection Space

The system allows for data collection anywhere. There is not limitation if the sensors are set to store data. If they are streaming, they need to stay within a certain range of the collection computer, usually 10 meters with standard WiFi (without additional antenna).

Sample Size

Data can be collected continuously. Some sensors can run into sensor drift if data collection is too long.

Data Processing Time

This is dependent on the algorithms and the desired data. Continuous collection means that unwanted portions of data need to be excluded. The acceleration signals need to be filtered and processed. The algorithms are the key to data processing times and data accuracy.

Data output

Some Temporal-Spatial Gait, some joint motion

  Zeno Walkway System Camera-Based 3D Motion Capture System IMU-Based Gait Analysis System
Common Data Output Temporal-Spatial Gait, Center of Pressure trajectories, Relative pressure, COMe Joint Kinematics and Kinetics, temporal-spatial gait Some Temporal-Spatial Gait, Some joint kinematics
System Makeup Rollout pressurized walkway Camera system of 6-16 cameras coupled with reflective markers and 2-4 force plates (force plates optional) Multiple inertial measurement units
Collection Space Dedicated lab space or any hard flat surface with portable models Dedicated lab space Most spaces
System Setup time <1 minute for permanent setup, <5 minutes for portable or initial setup Initial setup takes hours, daily setup requires dynamic calibration. < 5 minutes
Patient Preparation No physical preparation Reflective markers are placed in key anatomic positions. Time can vary from a couple minutes up to 30 minutes IMUs must be placed on the subject, <5 minutes
Data Collection/Sample Size Dependent on mat size, but commonly 6-20 steps per pass, with an unlimited amount of passes per trial Dependent on the number of cameras and force plates. Generally 1 pass per trial. Collect multiple passes per subject Data can be collected continuously but some sensors experience a decrease in accuracy due to drift if the collection is too long
Data Accuracy TS measures are direct measures. COP validated vs. Force Plate Kinematic and Kinetic data accuracy dependent on algorithms and marker placement. TS measure accuracy can vary depending on the labelling method. Data accuracy dependent on algorithms used and sensor quality.
Data Processing Time Majority of trials will be processed in <1 minute. Some difficult trials can take up to 5 minutes Can range from <1 minute for easy patterns with force plates to over 15 minutes for difficult patterns per pass. (often collect 4-6 passes per subject) Lack of force plates increases processing time. Dependent on algorithms and desired data. Continuous collection leads to unwanted portions of data needing to be excluded.