Publications

SSM Lee, D Gaebler-Spira, LQ Zhang, WZ Rymer, KM Steele, (2016) “Use of shear wave ultrasound elastography to quantify muscle properties in cerebral palsy.” Clinical Biomechanics

Dr. Steele JournalArticle, MotorControl, UbiquitousRehabilitation , ,
Sample ultrasound images from gastrocnemius and tibialis anterior showing greater shear wave velocity on more affected limb.

Journal article in Clinical Biomechanics:

Kat Steele partnered with Sabrina Lee from Northwestern University and the Rehabilitation Institute of Chicago to investigate shearwave ultrasound elastography as a new tool to quantify changes in muscle properties in cerebral palsy.

Sample ultrasound images from gastrocnemius and tibialis anterior showing greater shear wave velocity on more affected limb.Abstract: Individuals with cerebral palsy tend to have altered muscle architecture and composition, but little is known about the muscle material properties, specifically stiffness. Shear wave ultrasound elastography allows shear wave speed, which is related to stiffness, to be measured in vivo in individual muscles. Our aim was to evaluate the material properties, specifically stiffness, as measured by shear wave speed of the medial gastrocnemius and tibialis anterior muscles in children with hemiplegic cerebral palsy across a range of ankle torques and positions, and fascicle strains. Shear wave speed was measured bilaterally in the medial gastrocnemius and tibialis anterior over a range of ankle positions and torques using shear wave ultrasound elastography in eight individuals with hemiplegic cerebral palsy. B-mode ultrasound was used to measure muscle thickness and fascicle strain. Shear waves traveled faster in the medial gastrocnemius and tibialis anterior of the more-affected limb by 14% (P = 0.024) and 20% (P = 0.03), respectively, when the ankle was at 90°. Shear wave speed in the medial gastrocnemius increased as the ankle moved from plantarflexion to dorsiflexion (less affected: r2 = 0.82, P < 0.001; more-affected: r2 = 0.69, P < 0.001) and as ankle torque increased (less affected: r2 = 0.56,P < 0.001; more-affected: r2 = 0.45, P < 0.001). In addition, shear wave speed was strongly correlated with fascicle strain (less affected: r2 = 0.63, P < 0.001; more-affected: r2 = 0.53, P < 0.001). The higher shear wave speed in the more-affected limb of individuals with cerebral palsy indicates greater muscle stiffness, and demonstrates the clinical potential of shear wave elastography as a non-invasive tool for investigating mechanisms of altered muscle properties and informing diagnosis and treatment.

Perry Initiative: Inspiring future female engineers and orthopaedic surgeons

Dr. Steele AccessEngineering, Outreach, Presentation, Uncategorized , , ,

Seattle Children’s Hospital hosted the Perry Initiative this weekend to inspire women to pursue careers in engineering and orthopaedic surgery. Dr. Jacquelin Perry was one of the first ten women orthopaedic surgeons in the country and has been a mentor to countless women and men throughout her career. She is known for her work quantifying human movement using tools such as motion analysis, electromyography, and ultrasound. She developed new surgical procedures including methods to straighten spines and inventing the ‘halo’ to immobilize the spine, neck, and head.

Learning to fix bones with external fixation at the Perry Initiative.This weekend, 25 women from local high schools, joined surgeons and engineers at Seattle Children’s to learn about common medical tasks and cutting-edge medical technology. They tried their hand at casting, suturing, external/internal bone
fixation, and rotator cuff repair.

From the Perry Initiative: “Engineers and orthopaedic surgeons work hand-in-hand to develop safe and effective implants for repairing broken bones, torn ligaments, and worn-out joints. Strong partnerships between surgeons and engineers are essential for improving the performance of orthopaedic implants and creating solutions to unmet clinical needs.”

We agree! Here’s to many future collaborations with diverse teams of engineers and surgeons.

Sasha Portnova to present in The International Conference of Undergraduate Research

Keshia News, Orthoses, Presentation

AlexSasha Portnova is presenting her research on 3D-printed wrist-driven hand orthoses today in The International Conference of Undergraduate Research (ICUR). The conference is an annual multidisciplinary forum that connects students from universities in seven countries across the world. Sasha was the sole person selected from the ME department at UW to present. Great work, Sasha!

Capacity Building Institute

Dr. Steele AccessEngineering, OtherPublication, Outreach , ,

CBI participants.The proceedings from AccessEngineering’s first Capacity Building Institute have been published on-line.

This institute focused on bringing together faculty, staff, and students from engineering departments around the country to discuss how to support individuals with disabilities in pursuing careers in engineering.

There were many wonderful presentations and discussions. In particular check out:

These discussions helped to inform several new resources from AccessEngineering including:

The Capacity Building Institute was hosted at the University of Washington-Seattle April 7-9, 2015. Please let us know if you are interested in participating next year!