May 9 • Peter Malliaras

Monitoring Physical Activity Using Wearable Technology in People With Achilles Tendinopathy Undergoing Physiotherapy Treatment: A Feasibility Prospective Cohort Study

Hi everyone,

You may have come across a feasibility cohort study conducted by former PhD student Dr. Sanam Tavakkoli. I wanted to share some interesting findings from this study.

What we did:

Sanam followed 30 individuals who were undergoing community-based physiotherapy treatment for Achilles tendinopathy for a period of 12 weeks. She had them wear an IMU (inertial measurement unit) sensor for a week at baseline, and then again around 6 and 12 weeks. The aim was to determine whether we could monitor their physical activity (steps) and biomechanical surrogate measures during gait. The IMU is equipped with advanced components that accurately measure rotations and accelerations. We used swing acceleration as a surrogate measure of ankle propulsion, shank angular velocity at initial contact as a surrogate for impact, and peak stride rate as a surrogate for fastest walking speed.

What we found:

Surprisingly, the participants were happy to wear the IMU, and adherence was excellent (great job, Sanam!). This indicates that we can consider using IMUs to monitor physical activity for larger studies in the future.

We conducted preliminary data analysis and have summarized some key takeaways below:

  • Improvement in pain and disability over the 12-week period was modest and not clinically significant for many individuals. Generally, people tend to do better in randomized trials, possibly due to the Hawthorne effect.
  • There was a decrease in step count at 6 weeks, which returned to near-baseline levels at 12 weeks with no overall increase.
  • IMU measures of physical activity (average over the study) were more highly correlated with baseline kinesiophobia (fear of movement) than pain/disability.
  • Self-reported measures of physical activity did not show significant correlation with anything.

Why is this important?

Although this is just a starting point, our data confirm the need for better measures of physical activity and to pay attention to whether individuals who experience 'recovery' from painful conditions like Achilles tendinopathy also return to their desired physical activities.