Practical 2-Dimensional Running Gait Analysis

There is a lot of academic and instructional content surrounding analytical biomechanical analysis of running gait for physical therapists; however, there doesn’t seem to be a source of information on practical setup. Specifically, there is no guide for starting from scratch for this setup to being able to perform this service. The following post is meant to be a living version of that guide. While running gait analysis and movement analysis in general is starting to become more commonplace, it still doesn’t seem to be at the fingertips of the everyday clinician. The physical therapy profession can be improved with utilization of running analysis through demonstration of knowledge to the client/patient, diversified billing, and fostering community relationships.

Introduction:

To truly start with nothing, the physical therapist needs to demonstrate that running gait analysis is a worthwhile endeavor for their immediate supervisor and at least one link above them to pursue this. Let’s be specific and define running analysis and then ask the question why analyze someone run?

Definition:

Movement Analysis is the use of observation, media, or data recording to assist with analysis of movement. Observing or recording a person running is a type of movement analysis. Therefore, running gait analysis is observing a patient/client’s running gait. Moreover, in the clinical setting this is given by expert level recommendation to be a form of special test for a patient/client who runs to assist in diagnosis, and treatment of their condition. Physical therapists are advertised by the American Physical Therapy Association as movement experts.  Most therapists foundational training is rooted in observational movement analysis which positions them to be best suited to complete this clinically.

Why Analyze Running (improve scope of patient’s seen, diversify billable codes, and stand out among other clinicians, )

Physical exams have always been a robust tool for clinicians to use to diagnosis, treat, and re-evaluate patient conditions. They are strengthened with utilization of special tests that rule out and in specific conditions.  Running gait analysis is a form of a special test to identify running related injuries. While at the present time, research literature hasn’t evaluated sensitivity and specificity of form errors in gait mechanics that can be observed and proved direct causation with specific conditions. Reliability and validity studies have been completed that specifically identifies 2-dimensional video running gait analysis as both a reliable and valid tool for clinicians¹.

Summary Statement: Running Gait Analysis is a form of movement analysis that is reliable and valid to identify running forms errors associated with running related injuries. It is a type of special test that can be included as apart of a physical examination.

Improve the scope of your clinical abilities. Whether we like it or not, following completion of formal training a clinician leaves with an effective scope of conditions that can be treated. Initially this can be variable and can be inconsistent even within the same condition. Further education through residency and fellowship training allows clinicians to improve consistency, decrease variation, and broaden their scope of clinical practice among other improvements. Movement analysis and including running gait analysis is an appreciable and effective way to further improve a clinician’s scope of practice.  When a clinician improves their scope, schedules are full, patient satisfaction scores improve, and the providers ability to help the community is strengthened.

Diversify Billable Coding. Most physical therapists use the same four codes to bill all services that they provide: therapeutic exercise, therapeutic activities, neuromuscular re-education, and manual therapy. These codes have vast applications for clinicians. However, it is only a matter of time before insurance companies further tighten their reins on these codes, decreasing reimbursement or increasing administrative burden enough to make it difficult for clinicians to code properly. However, when significant testing is performed outside of the initial evaluation and progress re-evaluation, physical performance test and measures can be billed with running analysis. This code is meant to be utilized when the clinician spends a significant amount of time (about 15 mins) collecting and analyzing patient data that impacts the plan of care. Typical reimbursement is $50 per code with reasonable limits on how often this can be coded. With therapeutic exercise typically reimbursing $30 and manual therapy $25 use of this code can diversify billing and increase revenue through use. Understandably, this isn’t a massive improvement or a massive shift, but this profession needs to change its tradition and habits and begin wisely considering how breaking from norms can positively impact the profession, and its community.

Summary Statement: Running gait analysis can improve this clinic’s scope of patient’s treated, improve our quality of care, improve satisfaction scores, diversify billing, and improve the clinic’s revenue.

Stand out in the community. Reported amounts of physical therapists’ utilization of video based movement analysis is about 50%. For a profession that is advertised as movement experts this seems low. Thereby by adopting this technology and knowledge a local clinic can stand out even among larger provider groups. Movement analysis and running gait analysis are tools that other professionals utilize like coaches and personal trainers, so patients/clients are already used to seeing it. Popular sports channels like ESPN already show slow motion clips of athlete movement. Without a shadow of a doubt video analysis improves patient engagement in care, and therapeutic alliance. Once a patient sees themselves run in slow motion and the clinician identifies a form error that is costing the patient efficiency or causing an injury, they feel empowered to listen make change happen.

Okay hopefully at this point you are feeling encouraged that running analysis is a viable tool that assists your clinic in all aspects of operation. Next Let’s talk equipment:

Video Analysis:

Let’s start this topic by understanding 3-dimensional modeling vs 2-dimensional analysis. With 3-dimensional modeling 3-D cameras are utilized typically mounted on fixed positions through an open room, that identify marker placement on a person’s body. Markers are placed on anatomical landmarks and from those markers the cameras and corresponding computer system develop a 3-D model of a person. Once the person begins running on a treadmill the data collection for the 3-D system begins. These systems are expensive and take time to calibrate and setup. They aren’t typically recommended for clinical setup. In my opinion, 5 mins would be the max setup time for any test or treatment. If it takes too long there is usually something more practical and effective to use for the clinical setting.  Markerless motion capture systems are an innovation that can help bridge the gap between 3-dimensional systems and 2-dimensional systems.

              However, currently 2-dimensional systems are cost effective and efficient and most everyday clinicians can use them without much training. It’s a basic tool that meets that is fit to stand the test of time among things like gait belts, reflex hammers, goniometers, and others. Video based motion analysis is another item to add to the list in my opinion.

So, there are options for equipment and variation depending on user preferences, but what I want to focus on here is the most user friendly, and easily implemented solution.

Equipment:

Apple iPad Pro

Yep that’s it. Seriously just take your child’s iPad and begin shooting video of your patient’s running. Okay there’s a little more to it than that, but seriously a $1000 dollar investment in an iPad (honestly this could be less if you buy open box, older versions, or used versions) can be the tool you need to improve your scope, improve your practice, and further the physical therapy profession.

Why an iPad Pro, why not a Samsung or a Microsoft surface? I am excited to see what other device manufacturers come up with as camera and software improve. However, Apple’s iPad pro uniquely has the ability to shoot 120-240 frames per second when recording in slow motion mode. This is important because the human eye visualizes at a speed of 30-60 frames per second and is trying to analyze the movement at the same time. Therefore, the iPad captures the information faster and allows the person to slow the movement down for analysis. A tablet device is more universal to the task vs. just using a camera that uploads for visualization on a laptop. The iPad can record, analyze, and display the patient/client running all in one system, which makes the money worthwhile.

Treadmill:

Buy a used treadmill, have it serviced by a local professional who sells gym equipment or when possible the manufacturer and start with that. The treadmill just needs to be able to have a motor that is capable of handling belt speeds for running. Additionally, having a stiff deck treadmill allows for better visualization practically speaking. It isn’t wrong to analyze on a flexible deck but is something that should be taken into consideration when looking at vertical oscillation of the runner. Cost is variable here and depends on what deal you can get or where you buy it from. Some practical tips is that a more open deck for viewing sagittal running analysis is preferred. Some treadmills have handlebars that extend down laterally for safety for the athlete. Less is more here, we always want patient/client safety, and many treadmills no longer have bars that extend down, so if it is not necessary it is better to leave it out because it can get in the way of viewing movement. Another tip is checking how the treadmill starts up. Does it give the user notice or a countdown that the belt will begin moving. Likely you’ll use this treadmill for other uses than just running and people appreciate a warning that the belt is to begin moving. It can be surprising, but many running athletes haven’t run on a treadmill in a large amount of time, so user unfamiliarity should be accounted for, and the clinician should prior to the gait analysis familiarize the patient/client with their in-house system. That’s my PSA on that. Again, it seems unnecessary or rudimentary but it can’t be overstated that once you start this, you will notice that many people don’t regularly use a treadmill.

What about self-propelled treadmills? Are they better or are they worse? Well worse typically, because the patient is pushing the belt along which forces them to adopt a more forward lean in their gait cycle. This is just anecdotal I’m not aware of studies being done, nor do I regularly run on treadmills.

Other Features: There are features that can assist you such as pace calculators, speed calculators, and incline and decline features, but expect to pay more. Newer treadmills that come with subscription services can feel distracting, and seriously basic analog is great for quick glances for data capture. Most patients are only on the treadmill for about 10 mins for running gait analysis unless the clinician is purposely trying to fatigue their form. Therefore, entertainment isn’t needed.

Tripod:

Not completely necessary but certainly helpful, a tripod can stabilize the video and ensure that the perspective of the video is accurate.

Perspective: in case you’re not sure of this terminology, when completing video analysis usual views to take are sagittal and frontal views and this requires the camera to oriented in a straight plane. Essentially what I mean by this is that the camera needs to capture video in an upright position such as straight up and down. If the camera is tilted forward or backward at all the video becomes distorted and can skew the analysis.

Type of Tripod (coming soon)

Clinic Setup:

Having the treadmill in an open spot in the gym is a proper practical setup. To capture the full patient on the treadmill in the center of the viewing frame, about 7 ft laterally and posteriorly from the patient. This is favorable to have the treadmill setup ready to go for when the clinician requires it.

Analyzing the video. And share information with the patient. There are several free options for video analysis. Paid and unpaid apps can be used. CMV (Coach my video) is the only free application that I’ve currently used. From my own perusing the application store huddle technique and dartfish have moved to subscription services. If you transfer the video to a PC, Kinovea is a great option that is free to download.

Data capture: Use the screen shot feature, on current iPad pros, press the down volume button and the lock bottom on the top right of the iPad in order to take a screen shot of the plane of view and movement of interest that is clinically relevant in order to save the analysis. The most secure setup is to then plug the iPad into the clinician’s computer and transfer the file to the computer. File format from the iPad is usually a PNG and most EMR’s require a PDF or JPEG version to upload into their attachments/electronic documents/separate file sections. Therefore, prior to uploading complete a file conversion in whatever method you prefer. If you need more information on this request it for the next update of this page!

Marketing:

Okay so you are treating these patients and successfully becoming a local movement analysis legend in your community. Now you need to market your unique services. Hopefully you are consulting marketing information like apta.org private practice section for more advice on this. However, using social media marketing to assist with this is great. Advertising movement analysis as a tool for specific sports analysis and treatment and its benefits of which were listed above is a great way to start. Make a specific video content release form, releasing liability for HIPPA, block out the patient’s face (like using paint app on a PC), and post a video of movement analysis and how it affected the patient’s treatment plan to complete some advertising for your practice. More patients will be looking for your services once you post information like this. One pro tip with marketing is to always close the loop with your videos, make sure not to just post a video but to lead your customer to something whether it is a free screen, or phone call contacting for your office. 

Resources:

1. Pipkin A, Kotecki K, Hetzel S, Heiderscheit B. Reliability of a Qualitative Video Analysis for Running. J Orthop Sports Phys Ther. 2016;46(7):556-561. doi:10.2519/jospt.2016.6280