New smartphone app tracks human motion to aid physical rehabilitation

A team of US researchers has developed a smartphone app that can track and analyse a person’s ability to move from one place to another, known as locomotion, and other types of movements.

Researchers tested their app, called OpenCap, with 100 participants. Using two or more smartphones, the app recorded sufficient quality videos to allow for web-based, artificial intelligence analysis of muscle activations, joint loads and joint movements. 

Data collection took less than 10 hours for the 100 participants, and computation of results took 31 hours, according to the study published in the journal PLOS Computational Biology.

The study was conducted by Scott L. Delp of Stanford University and colleagues.

Traditionally, locomotion analysis requires fixed lab space and more than $150,000 worth of equipment, including eight or more specialized cameras to capture three-dimensional images. 

The captured data also takes several days to analyse by a trained expert. 

Human motion analysis is used to evaluate patients with movement difficulties, to help clinicians plan surgery, and to assess the results of treatment procedures. 

The research team funded by the National Institutes of Health believes that using the app costs about one per cent of conventional motion analysis techniques and works 25 times faster. 

While current technology is too expensive for routine clinical use, according to the investigators, the app could potentially be used to help screen for disease risk, inform rehabilitation decisions, and track improvements in motion following treatment.