Spotlight: Pelvic Stability

A good stable and upright sitting posture, especially one that promotes postural alignment and control, is a critical requirement for us to actively participate in meaningful activities of daily living.


If you have met me at a conference or training event you will no doubt have heard me drum in the importance of the pelvis – what happens there dictates what happens above and below it!

A person’s inability to achieve a stable sitting position can result in a decline in overall health over time.Instability at the pelvis will in turn affect a person’s trunk alignment, lower limb symmetry and head position; this poor positioning can impair vital physiological functions1, such as:

  • Respiration
  • Swallow  function
  • Digestion
  • Cardiac efficiency

Pelvic instability has many causes; some are intrinsic, such as abnormal muscle tone or limited hip range of movement. Fatigue also plays a significant role resulting in a person finding it increasingly difficult to remain upright against the forces of gravity – I am sure you notice it at the end of the day when you sink back in to your sofa at home.

If you take anything away from this blog today it is this: Another prevalent cause, even in those with no known postural abnormalities, that is often missed is incorrect seat dimensions. A specialist seating system is only as good as its set-up. A chair that is too deep for a person will make it difficult for them to bend their knees over the edge of the cushion; this will lead to them sliding down the chair just to get their feet on the floor resulting in an unsupported and unstable pelvis.

At CareFlex, we will never just deliver a box – we are always on hand to ensure the chair is set-up for the intended user and that all those supporting them can competently and confidently make any necessary adjustments. Our chairs are designed with flexibility and simplicity in mind.

Pelvic instability can present in many different ways, the most common being an increased posterior pelvic tilt where a person appears to be sacral sitting. This postural challenge can be associated with a tendency to slide forward in the chair, resulting in an increased risk of pressure injury over the sacrum.

Other presentations of pelvic instability include an anterior tilt, pelvic obliquity, and/or pelvic rotation. An anterior pelvic tilt is when a person presents with their pelvis tilted forwards; it can be associated with an increased lumbar curvature and therefore reduced functional reach.  A person with a pelvic obliquity presents with an asymmetrical pelvis falling to one side; this can be associated with a scoliosis and an increased risk of pressure injury on the lower side of the pelvis. A pelvic rotation occurs when a person presents with one hip further forward in the chair; it can be associated with spinal rotation and wind-sweeping of the lower limbs.

As you can see, pelvic instability isn’t an insular problem – it comes with, and even solely causes, several other postural challenges. You can read more about postural challenges, why they occur and how to manage them, on the Health section of our website.

We know that the use of the upper limbs is essential for our ability to function2, but what can be overlooked is the need for effective stabilisation of the pelvis and trunk3 for us to achieve this freedom of movement in the upper limbs. This is where CareFlex specialist seating can really shine…

Our chairs are designed with pelvic stability in mind, aiming to provide an upright, aligned sitting position with the pelvis supported in all planes of movement. Tilt-in-space can assist pelvic stability through utilising gravity, in turn improving energy management; it can also help with pressure redistribution to reduce the risk of pressure injury. There are options to ramp the base or add a pelvic strap, following a risk assessment, to further encourage and maintain pelvic stability. We have a range of back options to correct or accommodate trunk alignment and foot supports to encourage lower limb symmetry. Seat dimension adjustments also ensure correct set-up tailored to the person. You can read more about our unique products here.

My final piece of advice is: the key to effective stabilisation at the pelvis depends on the seating prescription, which depends on the assessment. At CareFlex we have a team of highly skilled and extremely knowledgeable professionals with many years combined experience of assessing for specialist seating, Get in touch now to book a free no-obligation seating assessment.



  1. Healy A, Ramsey C, Sexsmith E (1997) Postural support systems: their fabrication and functional use Developmental Medicine and Children Neurology 39:706-710
  2. McClenaghan BA, Thombs L, Milner M (1992) Effects of seat-surface inclination on postural stability and function of the upper extremities of children with cerebral palsyDevelopmental Medicine and Child Neurology 34:40-48
  3. 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