We’ve all heard it, and perhaps we’ve even asked it – “when do I choose to correct a postural deviation, and when do I accommodate it?”
[Note: When we discuss postural deviations, we typically talk about the pelvis: pelvic tilt, pelvic obliquity, pelvic rotation. Not to say that trunk lean, scoliosis, thoracic kyphosis, or cervical hyperextension, among others, are not important postural deviations (they are!), but we are confident that the position of the pelvis can give us the most insight on the impact of the rest of the kinetic chain in sitting, so that is where we focus first during our assessment and in our conversations about postural deviations. We’ll make another post diving into this on a much deeper level soon – so for now we’re asking for your trust as we take you through our thought process on this particular topic 😊]
Personally, I do not like to use the term ‘correct’ when referring to postural deviations when discussing seating. If you have ever worked with us, or attended a seminar or hands-on workshop, you know very well that the core principle we hold very near and dear is to respect the body and any structural limitations that exist. In this sense, we don’t ‘correct’ a postural deviation through the seating system, but rather we ‘accommodate’ it by respecting the structural limitations discovered through our hands-on assessment.There are certainly times when the postural deviations we see are caused by ill-fitting seating systems and/or poorly configured chairs, however for the purpose of this post we will focus on structural limitations in the body.
Let’s take an example directly from an article we recently came across regarding exactly this:
“If one side of the pelvis is lower than the opposing side, a pelvic obliquity is present, and is subsequently named for that low side. After identifying this obliquity, the assessing clinician must now determine if the client presents with a correctable or non-correctable asymmetry (obliquity). The clinician can accomplish this quickly and easily by placing his or her hand under the low side of the pelvis and gently lifting the low side of the pelvis in an attempt to raise the low side of the pelvis to a height equal to that of the high side. If the clinician is successful in neutralizing the pelvis, it can be surmised that the patient has a correctable pelvic obliquity. If the clinician is not successful in neutralizing the pelvis and the obliquity persists despite an attempt at neutralization, the client presents with a non-correctable pelvic obliquity.”
If we are able to ‘correct’ a pelvic obliquity with the person sitting in their wheelchair or on a firm surface, perhaps the pelvic obliquity is not actually a structural pelvic obliquity, but is the symptom of a structural limitation somewhere else along the kinetic chain.
Furthermore, if we were to lift the low side or push down on the high side of the pelvis to ‘correct’ the pelvic obliquity in sitting, what changes are we causing throughout the spine and lower extremities - changes that we might not be able to see or appreciate with the person fully clothed in front of us sitting in their wheelchair or on a firm flat surface? Sure, we may be able to ‘correct’ the pelvic obliquity this way, but at what cost?
So… what does this really mean? What might we do instead? Like most things (or all things?), this leads back to our hands-on assessment.
If our hands-on supine assessment reveals that the pelvic obliquity is caused by a limitation in hip flexion mobility, for example, our seating solution may accommodate the structural limitation of the hip, thus eliminating or decreasing the amount of obliquity present in sitting. If our supine hands-on assessment reveals that the pelvic obliquity is non-reducible, or “fixed” – perhaps due to structural scoliosis or shortening of the lateral trunk musculature – our seating solution will accommodate the pelvic obliquity by providing inferior, posterior, and lateral support where appropriate to mitigate progression, decrease the work of sitting, and facilitate function. A postural deviation that is non reducible, or “fixed”, is not static and can therefore continue to get worse if it is not supported adequately.
Either way, we are not ‘correcting’ the deviation, but rather accommodating the structural limitation contributing to the presenting symptom.
Another example we hear often is related to posterior pelvic tilt:
Let’s imagine we are working with a client who presents with a posterior pelvic tilt when sitting in their wheelchair, and they often complain of sliding forwards out of their chair throughout the day.
If we jump right in to potential solutions to ‘correct’ the presenting symptom (a posterior pelvic tilt with consequential sliding), we have many potential options that are commonly used. We might choose to add a pelvic positioning belt that can be tightened so that the person is held in their wheelchair with a ‘more optimal’ posture and with less of a tendency to slide forwards. We might add a medial thigh support (previously known as a pommel or a hip abductor) to create a barrier or slope that will theoretically prevent the person from sliding forwards. We might add posterior tilt in space to utilize gravity to help keep this person back in their wheelchair, making it more difficult for their body to slide forwards. We might even believe that adding elevating leg rests will help keep this individual in their chair! These additions will likely be combined with training for the wheelchair user and/or carer about the importance of keeping the hips as far back in the seat as possible to further help ‘correct’ the presenting symptoms.
Each previously mentioned intervention may sound reasonable if you are interested in applying a ‘band-aid’ to the symptom rather than understanding the underlying cause. However, adding external forces to an existing problem will only exacerbate the internal problem or underlying cause.
Rather, we observe the presenting posture and take note of the subjective reports of sliding forwards, and immediately move into a hands-on assessment to fully understand what is causing the posterior pelvic tilt and resulting sliding.
Upon further examination, perhaps we find that this person has the ability to achieve a neutral pelvis and lumbar lordosis in supine, and they have significantly shortened hamstrings.
Based on our knowledge of anatomy and biomechanics, we understand that this shortening is most likely the cause of their presenting symptoms (posterior pelvic tilt). In order to accommodate this limitation in body structure, we need to respect the length of the hamstrings by setting up a seating configuration that allows them to rest in a position where they are relaxed, thus decreasing or, hopefully, eliminating the presenting symptoms.
Many times, clinicians will immediately ask if this seating solution (with the hamstrings in their shortened, relaxed position) will be contributing to the problem. In other words - by keeping the hamstrings in the shortened position, are we not just facilitating continued shortening? Wouldn’t it be more ideal and effective to place the hamstrings in a position at end range or where they are slightly stretched, as we know that shortened hamstrings are an issue and there is potential to implement a prolonged stretch when this person is in their wheelchair?
The answer, to put it bluntly, is no. Because the body will always win. Because, as we say over and over again, the wheelchair is an extension of the human body - it is not a tool for therapy or a modality for changing limitations in body structure.
If we position those hamstrings in a lengthened position so they are not relaxed, either the feet will end up posterior to the foot support or, more likely, the pelvis will return to it’s position of posterior pelvic tilt. This might not happen within the first few minutes of sitting in the chair, but it will undoubtedly occur over a period of time.
A wheelchair is not an intervention meant to stretch and strengthen. A wheelchair is an assistive device meant to promote function, independence, and protect body shape.
As a therapist, this was a challenging concept to initially buy into. So many of our interventions and treatment modalities are geared towards fixing or correcting or creating positive change in body structure. Understanding and respecting that the goal of seating is not to ‘fix’ or change a person’s body structure is probably the most crucial and valuable piece of information we can try to share with our clients and colleagues.
Changes, or ‘corrections’, happen outside of the wheelchair - through active therapy, medical or surgical management, and alternative or night-time positioning. A wheelchair is an extension of the wheelchair user’s human body, and in this sense it is clear that the wheelchair must then respect and accommodate that body and any structural limitations it may have.
So, next time you find yourself able to ‘correct’ a postural deviation in seating, perhaps take a moment to consider that the deviation may be a symptom caused by a limitation somewhere else in the body – then confirm your hypothesis with a thorough hands-on assessment in sitting and supine. In the absence of limitations in body structures, perhaps the technology being used is the source of the problem. And while ensuring that the seating system and wheelchair configuration we prescribe adequately accommodates the limitations we discover, also consider what interventions can be implemented to correct or influence positively those limitations when the person is not in their chair, with a goal of improving their ability to sit with as little compromise as possible throughout their life.
We would love to hear your thoughts on this! Do you ever opt to ‘correct’ rather than ‘accommodate’? Perhaps you use those terms in a slightly different way that can also contribute to our greater understanding of how to prescribe appropriate seating solutions?
Leave a comment and let us know!