Are the feet really that important if we are sitting down?

Posture is essentially the position of one or many body segments in relation to one another and their orientation in space:

Postural management is the use of any technique to minimise postural abnormality and enhance function2. An effective postural management programme will address all of these body segments throughout an individual’s full 24-hours.

How can specialist seating help?

Specialist seating can form a critical part of an individual’s posture management programme. Specialist seating can address all body segments; however, for the purpose of this blog, we will be focussing on the feet segment.

With regards to the feet, we are aiming to correct the foot posture to achieve a neutral plantargrade position, especially if an individual needs to maintain range of movement for mobility, with maximum contact with the support surface:

Some individual’s present with fixed foot deformities, which will be identified following a comprehensive postural assessment. These individuals may require a softer foot support to accommodate their posture to ensure equal weight distribution and comfort, and to reduce the risk of further postural deterioration:

At CareFlex, we also offer a specialist Custom Made Device (CMD) service. During the seating assessment, it may become evident that a unique modification is required to achieve optimum posture and pressure management. If so, details are passed to our CMD team, who then produce a schematic drawing and quotation. Sometimes the modification can be a simple accessory; in other instances it can be a significant alteration to the structure of the chair. We have many years of experience producing unique CMDs – so if you have an idea that you think would work for a particular individual, get in touch!

Why are the feet so important?

Posture and pressure are inextricably linked; body positioning has a direct influence on the pressure going through specific body sites3. Most of us have heard of the gold standard 90-90-90 sitting position, with slight anterior pelvic tilt, and hips, knees and ankles all at a 90° angle. This isn’t an achievable consistent or functional posture in real life; however, even if it was, our body weight would be distributed as follows4:

  • Through buttocks and thighs: 75%
  • Through the feet: 19%
  • Through the arms of the chair: 2%
  • Through the back: 4%                                                    

Activity 1:

June, a 5-foot lady who resides in a care home, sits down in a chair in the lounge after John, a 6-foot gentleman, goes out to the garden. John can sit comfortably in the chair with his feet supported on the floor. The chair does not have seat depth or seat width adjustability, or seat height options.

Question 1) Do you think June will be able to sit with her feet supported on the floor?

Question 2) Without her feet supported, where does 19% of June’s body weight go?

June could potentially have 94% of her body weight just going through her buttocks and thighs, and we wonder why individuals are sadly developing pressure injuries.

Supporting the feet and lower limbs can:

  • Aid pelvic stability
  • Encourage optimum foot position
  • Offer a platform to reposition
  • Facilitate comfort

Freedom of movement in the upper limbs is achieved through effective stabilisation of the pelvis and trunk5, which can be encouraged with appropriate foot support as all body segments dictate one another. It is vital that an individual feels stable as this will allow them to remove their upper limbs from a load bearing role to reach outside their base of support and complete activities of daily living.

Activity 2 (disclaimer: please only try this activity if you feel confident in your abilities):

In sitting with your feet supported, reach forward as if picking an object up off the floor. Now take both feet off the floor so that they are unsupported.

Question 1) Do you feel stable?

Question 2) Would you feel able to confidently and safely pick up the same object?

 

Learning points

  1. Addressing an individual’s foot posture is vital to achieving postural stability
  2. Postural stability can encourage freedom of movement in the upper limbs for function
  3. Appropriate foot support can help reduce the risk of pressure injuries
  4. A thorough assessment is needed to ascertain the best foot support for an individual
  5. In a multi-use environment, such as a care home or hospital ward, different chair dimension options are essential

Please do not hesitate to contact us if you have any specific queries around foot support.

References:

  1. Pope PM (2002) Posture management and special seating In Edwards S (Ed) Neurological Physiotherapy London: Churchill Livingstone
  2. Farley R, Clark J, Davidson C, Evans G, MacLennan K, Michael S, Morrow M, Thorpe S (2003) What is the evidence for the effectiveness of postural management? International Journal of Therapy and Rehabilitation 10(10):449-455
  3. Sprigle S, Wootten M, Sawacha Z, Theilman G (2003) Relationships among cushion type, backrest height, seated posture and reach of wheelchair users with spinal cord injury The Journal of Spinal Cord Medicine 26(3):236-243
  4. Collins F (2001) An adequate service? Specialist seating provision in the UK Journal of Wound Care 10(8):333–7
  5. Green EM, Nelham RL (1991) Development of sitting ability, assessment of children with a motor handicap and prescription of appropriate seating systems Prosthetics and Orthotics International 15:203-216