Seating Terms to Know: Part 2

By Lee Ann Hoffman, O.T., MSc. Rehabilitation

September 23, 2017

Topics: Wheelchair Lifestyle

You may have come across several terms used to describe seating or the components of seating. Let us help you clarify a few of the terms that relate to seating systems.


Postural Stability


Postural stability refers to the individual’s ability to experience a stable foundation for movement and function. It can be defined as the key to enabling the body to efficiently perform functional activities. To achieve this, adequate seated stability and trunk control is required. Postural stability is needed to carry out activities of daily living such as using the arms for movement during functional activities.


Wheelchair users may experience decreased or loss of trunk control. This may negatively impact aspects of their sitting balance and stability.


Postural stability can be improved and needs can be met. This begins with a comprehensive assessment to determine what type of support the individual requires to be seated in a balanced, functional, and comfortable position.




The trunk is often used synonymously with upper body or torso. It refers to the area below the neck and above the pelvis.


Lateral Thoracic Supports


Lateral – at the sides of the body


Thoracic – referring to the upper body


Lateral thoracic supports promote the upper body positioning and are located on the left and right side of the upper body.


Lateral thoracic supports are often supplied in pairs and may be either mounted at the same height on both sides or may be offset to address a postural asymmetry.


Lateral thoracic supports come in a variety of lengths, shapes, and sizes with a variety of mounting hardware. Lateral thoracic supports are available with swing away or removable hardware that allows them to ‘get out of the way’ for a lateral transfer or when using a safe patient handling hoist and sling system.


Consider the width and bulkiness of the lateral thoracic supports as this may negatively affect arm position, resulting in arms being positioned further away from the body. This can make functional tasks more challenging.


Be sure to check that the lateral thoracic supports are not too wide or bulky, as this may negatively influence the arm position (as it may take your arms away further from the body) and make propelling the wheelchair more challenging.


Note: Lateral thoracic supports are generally fitted to the back-support system. Be aware that on some manual and power wheelchairs that have a back-reclining function that is not intuitively designed, the lateral thoracic supports may move up on the body (due to the back-reclining system) and place undue pressure on the axillae (armpit area). Be sure to check if you do need or use a back-reclining system that it has a low shear feature during the reclining function to prevent this phenomenon and help ensure that both the back support and the lateral thoracic supports continue to provide support where needed.


Anterior Supports


Anterior supports refer to a chest support that provides the upper body with positioning. It should work as part of a positioning management plan within the seating. Anterior supports come in multiple shapes and styles. Make sure that the one you choose respects your body’s shape and provides the correct anatomical support.


Note: For anterior supports, consider the space between the top of the anterior support and the individual’s body. Ensure that the anterior support is allowing the individual to safely breathe, swallow, and communicate and is not a safety hazard. Many individuals slide down in their seating system during the day, which means that their body position is lower down, which may result in the anterior support no longer having a safe space between the support and the individual’s throat area. This can become a safety hazard or risk. Assessment and review are always best practice to ensure that the anterior supports selected continue to provide appropriate and safe positioning. 


Always check to make sure the section of the anterior support that is located at the shoulders is not pulling the individual’s posture down and forward. Make sure that the points of attachments are stable and correctly mounted. Check for signs of wear and ensure that supports are replaced in a timely manner.


Proper cleaning of the anterior support is essential, as it is frequently in the ‘catch zone’ for food, drinks, and saliva.


Remember: The anterior support forms part of a positioning system. It is not the sole positioning system or to be used as the sole wheelchair occupant restraint during vehicular transport. Be sure to check that the wheelchair occupant restraint system and the anterior supports are meeting the individual’s postural and transportation needs.Post SCI: Entering Back Into the Workforce


Lee Ann Hoffman, O.T., MSc. Rehabilitation

Lee Ann Hoffman, O.T., MSc. Rehabilitation

Lee Ann qualified as an Occupational Therapist in 1999 in South Africa. She completed a post graduate certificate in Posture Management for complex disabilities in 2010, and obtained a Master of Science degree in Rehabilitation: Posture Management, 2015 in the United Kingdom. Lee Ann has experience in working with children and adults with complex disabilities and adopts the 24-hour approach to postural management. She is currently a clinical educator for Invacare USA.

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