TrueMotion: turning a phone camera into a 3D motion lab

Musculoskeletal (MSK) care works best when it's personal and easy to do anywhere. At Hinge Health, TrueMotion® - our 3D computer-vision engine - turns a phone camera into a 3D motion lab, reading 100+ anatomical landmarks in real time to give precise, on-screen exercise guidance.

Since launching in 2023, we've shipped dozens of TrueMotion upgrades, including a smart skeletal model that adds depth perception and a spine-curvature view for more intuitive visualization. We're now introducing a movement analysis tool that runs members through a set of movements creating HingeScores, an objective first-of-its-kind metric that compiles precise measurements to help members track progress and better inform more personalized care plans.

Here's how TrueMotion works - and why it's changing MSK care.

Behind the scenes: how TrueMotion works

3D pose estimation for unmatched accuracy

For TrueMotion to deliver meaningful feedback and guidance, accurately estimating human body landmarks in three dimensions is paramount. Other systems rely on simpler 2D pose estimations, which are particularly susceptible to inaccuracies stemming from a person's orientation relative to the camera - they essentially break when the camera angle changes. Such discrepancies significantly degrade the quality of feedback, compromising the essential purpose of guided exercise therapy.

Our 3D visualization (or "smart skeleton") enhances guidance by displaying depth-indicating joint markers to illuminate movements such as spinal curvature. It also expands visibility to additional joints-including the pelvis and big toes-providing comprehensive, intuitive visual cues for a deeper understanding of body mechanics.

We've focused significant research and development in building a robust 3D human pose estimation platform that accurately analyzes complex movements without requiring restrictive phone placement.

Purpose-built for the real world

Unlike other computer vision solutions limited to tightly-controlled conditions or inconveniently requiring tablets that need to be shipped, maintained, and returned - TrueMotion is purpose-built for robust performance in the real world:

• Adaptable: It accommodates a wide range of body types, clothing, movement patterns, and lighting conditions.

• Accessible: It works on smartphones members already own - no need for additional devices or wearables. This deliberate choice reduces barriers to adoption - members can get started as soon as they sign up and download our app, without having to wait for specialized equipment to arrive.

• Seamless: Activating with just the phone's built-in camera, TrueMotion delivers real-time 3D motion tracking from anywhere, anytime, no complex setup needed. This creates an intuitive experience that fits easily into any routine.

By prioritizing frictionless adoption, we ensure our technology fits naturally into members' daily routines, reducing barriers to care and expanding access for all.

Introducing the HingeScore

Enhancing subjective outcomes with objective metrics

There are many measurement tools available to track MSK outcomes. However, almost all rely exclusively on subjective questions and are therefore self-report only - especially when collected outside the clinic. That makes sense when the main outcome measure is pain or stiffness, but function matters too - and that's hard to measure objectively via a survey.

That's why we've introduced the HingeScore: a first-of-its-kind composite measurement that combines quantifiable movement data and self-reported insights, giving a more complete view of a member's joint function.

How it works

With our new movement analysis tool, members will be guided through a comprehensive set of movements that precisely measures range of motion, alignment and soon, endurance. These objective metrics are combined with focused, member-reported questions on factors like pain and stiffness that are answered through augmented reality overlays.

Together, these insights generate a member's HingeScore, a more complete picture of their joint function. Members can see exactly where their score fits across categories like limited, moderate, strong, or exceptional, and visually follow their progress through up-to-date charts. This empowers members with deeper understanding and actionable insights to stay motivated along their musculoskeletal journey.

Why it matters

The HingeScore is an easy-to-understand number that gives:

• Progress you can see: objective validation of progress overtime

• Actionable care: clinicians get a real-time composite view of both subjective data (pain, stiffness) and objective functional outcomes to better tailor and optimize care plans

Lastly, our expanding dataset means our HingeScores have the potential to one day be the most comprehensive and validated clinical outcome measure in orthopedic care. (Watch this space…)

Building the Future of Digital MSK Care

By combining robust computer-vision models with member-centric design, TrueMotion helps people understand their bodies, follow form cues with confidence, and stay engaged-without needing special hardware or complicated setup. As our dataset grows, the Hinge Score will continue to refine recommendations so everyone's care gets better with use.

We're just getting started.