Trunk Stiffness Bending Device

Trunk control and postural habits greatly influence muscle movement in the rest of the body. The purpose of this project is to design an addition to the Twister mechanism device that measures axial muscle tone in an upright test subject.

Development and Project Goals
The Department of Neurology at Oregon Health and Science University developed the Twister device to study the regulation of tonic muscle activity during active postural maintenance. Twister measures torsional resistance and muscular responses in standing subjects during the twisting of the body axis. the device can be flexibly configured to study various aspects of tonic control across the neck, trunk, and/or hips. []

Problem Definition
Our goal is to evaluate the Twister mechanical and electrical components and determine how to make the device functional in an Motion Capture Laboratory. A subsystem consisting of a mechanism to detect lateral responses caused by external forces will be added to the existing structure to allow for a more complex data analysis of human axial tone.

Background
Postural habits can greatly affect a person's life physically and mentally. Studies have shown that patients that had postural intentions had corresponding postural alignment traits. A person's state of mind can influence how they act, move, and react to known and unknown lateral forces against them. A hunched and arched posture can influence other muscles in the body and can increase the chances of injuries. A person with relaxed mood will typically have a relaxed posture, as will a person with a high stress levels will usually have a rigid posture. The leading accidental causes of death for people aged 60 and above are falls. Senior citizens that do survive a fall have a 90% chance of a fracture of the hip. 40% of people with falling related injuries will be in chronic pain and will be dependent on medical assistance. Risk factors for falls include ergonomic factors as in falling off a ladder, tripping over a curb, or slipping on a puddle. Intrinsic factors like age and disease also contribute to an increased risk of falling. Postural instructions, lighten up, relax, and pull, also affect mobility. When a person knows that a force is going to be exerted towards them, their muscles tense as they get ready for the force. It creates a reaction that is completely different than an unknown force contacting a person. Comparing data related to mental responsiveness to physical responsiveness will help researchers figure out how and why people fall and the cause of negative postural habits.