A COMFORT CRUTCH THAT REDUCES AXILLARY PRESSURE
Axillary, or underarm, crutches are the most common short term use mobility aids that transfer body weight from the legs to the arms and torso. Incorrect crutch usage can lead to severe injuries like brachial or crutch paralysis, which is the paralyzation of the radial nerve cause by constant pressure to the radial nerve or brachial plexus. My goal is to redesign the crutch pad in a way that relieves the pressure applied to the underarm region and decreases the risks for these secondary injuries.
USER RESEARCH
Based on insights from interviews and personal user testing of axillary crutches, I discovered that there is constant pressure on the armpits and sides from the crutch pads during consistent use. When looking at existing products and methods to relieve some of this pressure, I saw many solutions that added foam, gel, or softer coverings to the crutch pad, but the crutch pad itself remained stiff and unchanged. My ideation and prototyping involved compliant mechanism that allowed for movement of the crutch pad to aid in relieving underarm pressure.
IDEATION & PROTOTYPING
I created prototypes with different types, layers, and locations of foam to determine the best combination for comfort. In tandem, I designed several plastic bases to understand how the form influences the comfort. Due to the pain point on the front of the crutch pad as you move forward, I iterated upon a compliant mechanism with a spring to allow for such motion with decreased pressure to the axillary region.
Through creating and testing dozens of 3D printed and foam prototypes, I focused on a design concept that involved a beam that has the ability to flex as you apply downwards pressure and and a spring to provide resistance as the beam flexes.
Many iterations were created to test how the gap between the beam and crutch pad base, and the spring rate impacted the ergonomics of the crutch pads. In addition to the foam padding on the top of the crutch pad, foam padding was also added on the side of the crutch pad to reduce the pressure crutch pad along the side of the upper body.
FINAL DESIGN
REFLEX CRUTCH PADS