Seating 101: Understanding the Basics

Seating 101: Understanding the Basics

Seating systems range from very complex to very simple. Within this complexity reside terminology and phrases that are the same regardless of the complexity. This article is designed to help identify and educate the consumers/caregivers on basic seating principles and what to look for in a therapist that is evaluating a child for a seating system. This article is part one of a two part series. The second part will focus on how to identify a seating system for the child.
First, let’s delve into the basic terminology for seating systems. This section will be listed as a glossary for ease of reading and finding terms later for which one may need clarification.  
Anti-thrust Wedges:
These are wedges that are designed to create a gradual closing of the hip angle so that the thighs and pelvis are able to weight bear and distribute pressure evenly throughout the seat. The anti-trust wedges place the knees above the hips and help reduce extensor tone and/or the forward sliding movement.

Chest Support:
Also known as chest harness. This comes in a variety of styles; ranging from a simple chest strap to harness. The chest harnesses come in a variety of styles and are made from different fabrics. The goal of the harness is to offer support to the chest to help maintain an upright position.

Closed Hip Angle:
The process of decreasing distance between the chest and knees. This can be accomplished by positioning knees above the hips or leaning forward, bringing the chest towards the knees. For an exaggerated image of knees above hips, picture sitting in a preschool chair as an adult and how much higher knees are than hips.  The goal of decreasing the hip angle is to decrease extensor tone, promote upright positioning, and positioning for function. Decreasing muscle tone requires multiple strategies, often this is a starting point. A person must be able to tolerate this closed position; which may be limited due to hip complications or muscle tightness.
Contoured Seating:
This type of seating contains depressions, raised areas, valleys, etc. The goal of this style of seating is to offer the most contact to the child so that positioning is enhanced. Many times, contouring assists with tone management.

The positioning device for the head. It ranges from a simple padded surface to a more complex system. Headrests can also range in their ability for adjustments. Some headrests only move up and down, others may move in and out to better position the head, or rotate slightly.

Hi-Low Base:
This is a base for modular seating systems that can be adjusted easily so that the child can access the floor and then be raised to a table height or vice versa. This is a great feature to decrease the lifting and positioning needs for the caregiver. It also allows the child to access more areas in their environment. Lastly, a hi-low base affords the opportunity for transfer training since the child can be lowered until their feet touch the floor.   
Hip Abductor:
Also referred to as a pommel. This is a padded area that can be built into a cushion or as a separate attachment to the seat. The goal is to maintain an abducted position (legs slightly apart) this can be for tone management, to maintain a good position for the hips, or to prevent knees from pressing together to name a few. It is not designed to keep a child in the seat or stop the sliding forward movement out of the seat; other seating features are better suited for this.
Lateral Supports:
These are additional features on a seating system that provide support to the trunk of the body. Many times they are positioned a couple of fingers below the armpits. They should enhance positioning; conversely a child should not “hang” on the laterals so that they are digging into the armpits potentially causing complications. Laterals can also be placed higher on one side than the other to accommodate/correct trunk leaning.

Open Hip Angle:
The opposite of closed hip angle: the process of increasing the distance from the chest and knees so that the knees are below the hip. This can also be accomplished by reclining the back rest. The goal of opening the hip angle is largely done to increase tolerance for sitting, accommodating muscle or joint range of motion limitations; or it is just the best position for function for the child.

Pelvic Belt:
This is also commonly referred to as a seat belt. But it is not an optional accessory to achieve the best positioning. The pelvic belt helps to position and secure the child in that position. There a variety of sizes and styles. Pelvic belts also need to be snug, with only 1-2 fingers being able to slide under the belt.

Planar Seating:
This type of seating is flat for the seat cushion and the backrest; meaning that if there are no hills/valleys/indentations, etc.  

The process of leaning the backrest back to reach a more horizontal position. The back component only moves, the seat is stationary. Recline is great option for managing g-tubes, suctioning, rest, toileting management (if the recline feature is capable of full recline).

The process of moving the entire seating system (back and seat itself) together as a unit along an arc. The seat angles stay the same. Picture sitting in a chair and leaning back on the back two legs, the body is in the same place in the chair (back on backrest, seat on the seat) but the view of the room is different. Tilt offers pressure relief, postural rest breaks, while maintaining the needed positioning assistance from the seating system. It is possible to get a system with both tilt and recline.  
    As mentioned, this is a very basic list of terminology that a caregiver might hear while perusing the internet for seating systems or while at a therapy appointment for a new seating system. As a caregiver, what qualities should a therapist exhibit during an appointment for a seating system?
    First and foremost, the therapist needs to find out the caregiver’s and the child’s goal for the seating system and the problems they are currently experiencing or areas of concern. This can dictate what type of seating system needs to be explored. Secondly, the therapist should take the time to complete a proper medical history and a mat assessment. The medical history includes a review of medication, therapies, height, weight and any past and future/planned surgeries. The mat assessment involves taking the child and positioning them on a therapy table in both a lying down position and a sitting position to look at a child’s typical sitting position, range of motion, hip and spine alignment, skin integrity, muscle tone, tolerance for correction and any limitations that may impact sitting tolerance (i.e. contractures, trunk rotation, scoliosis, pelvic asymmetry, etc.). If the therapist does not take the time to complete these basic steps; the odds are not in favor of getting an appropriate piece of equipment that a child can tolerate. Thirdly, a therapist should also have a variety of equipment on hand for the child to try during the appointment or even over a few appointments in the coming weeks. This helps to eliminate any seating systems that are not good fits and select those that are. Lastly, the therapist should include the caregiver and the child in the decision making process. The therapist should explain all of the features and components of the seating systems and objectively provide a list of pluses and minuses of the equipment for the child as well as their follow-up system once the child has the seating system.
    If a caregiver attends a seating appointment and these steps are not being followed, please remember that a second opinion can always be requested as well as trials with the equipment. Not all therapists have adequate training for completing an equipment evaluation, if you feel the therapist is not experienced enough to handle the needs of the child, please go elsewhere or ask for a more experienced therapist. Seating systems are only approved every 5 years on average; which is a long time to have a seating system or other adaptive equipment that does not work for the child.
    If at any time, it becomes too confusing or difficult to navigate through the world of seating systems or any other piece of equipment, please do not hesitate to contact us here at Tadpole Adaptive. We are always willing to provide unbiased and informed guidance.