The 50% In-Brace Correction Myth
Some of my readers may have heard of 50% in-brace correction, some may have heard of it but do not understand what it means and some already have an understanding, but for those of you who have not, let me start from the beginning.
What is scoliosis and why is it called a 3-dimensional condition?
Scoliosis is a 3-dimensional condition of the spine. This means that the body is affected in all three planes: coronal, sagittal, and transverse. The coronal plane is what we see when we look at the body from the front or back. The sagittal plane is what we see when we look at the body from either side. Transverse plane is when we look at the body from the top or bottom. Scoliosis is present when there is rotation of the vertebral bodies, and sagittal/coronal curvature of the spine. When treating scoliosis with a brace, we need to consider all three planes and the body as a whole in order to treat it appropriately.
What is the goal of bracing?
The three primary goals of scoliosis bracing are to:
- Derotate the vertebral bodies
- Elongate the spine
- Stabilize the spine
How are these goals measured?
- We can objectively measure rotation using a scoliometer.
- We can measure elongation by measuring the height change of the body with and without the brace on
- We can measure stabilization by the amount of decompensation to vertical and change of the curve over time
Oftentimes my patients will ask me what their physician meant when he said “the brace is getting 50% correction”. The unwritten “standard of 50% correction” that was developed over time in the treatment of scoliosis is that the brace should achieve fifty percent correction immediately after donning in order to be considered effective. For example, if the angle of the person’s thoracic curve is measured to be 36 degrees, the expectation of the brace’s correction would be 18 degrees in-brace.
In 2013, Knott published a research study which analyzed in-brace correction, retrospectively (1). The aim of the research was to help develop a standard of expectation to be able to qualify the effectiveness of scoliosis bracing. It is critical that outcomes of our interventions are assessed for their effectiveness.
However, it is just as important to recognize that the human body is complex and placing a numerical value on an intervention to represent the mass of individuals within the group of adolescents may be both helpful and detrimental to patients.
How is it helpful?
It is helpful to be able to reach an expected objective outcome so that the Orthotist, Physical Therapist, and Physician have a confidence level that the intervention is accomplishing the primary goal that was intended.
Establishing an objective goal for the intervention gives patients and parents a sense of peace of mind that they are doing everything they can to help improve the condition.
How could this be detrimental?
If a person’s curve is rigid, only a certain amount of correction can be obtained with the use of a brace. The primary goal then becomes to prevent progression, not necessarily to obtain 50% correction. If the contact point(s) is(are) increased, becoming a force to the body with the goal of more correction to a curve which cannot be reduced, and the body cannot move away from this force, Wolff’s Law comes into effect. Wolff’s Law states that bone responds to an applied force (stress) by undergoing an architectural deformation, and the bone strain is a measure of that deformation (2). Simply explained, Wolff’s Law states that your bones will adapt based on the stress or demands placed on them. Under the stress of force, bones will bend or flatten. As a result, the patient’s rib cage can become flattened, and skin breakdown and bruising is likely to occur. I have done consultations with many patients with flattened rib cages from the brace pushing so hard against a rigid curve that the body has to deform itself to accommodate the brace. The deformity is permanent and visible. Unfortunately, I see this often and as you might guess it occurs in the most compliant patients. The patients who are wearing the brace all day and through the night, doing the best they can to help avoid potential surgery and improve their self-image. Many times, these patients are coming in for the consultation because their current brace is not obtaining the amount of correction of the scoliosis that they were hoping for. After evaluating and finding that the curve is rigid, I explain that a brace will not be able to correct a rigid spine and that our goal should not be 50% correction, but to improve the body’s balance, prevent progression and avoid surgery.
In addition, if too much correction is made to one curve without controlling the rest of the spine, the scoliosis moves either up or down, therefore creating a new curve that may be much more difficult to treat, or worse, goes unidentified.
Finally, if there is an overcorrection of the curve, the vertebrae can be over-rotated which can cause imbalances and compensatory movements, therefore creating a new problem.
Patients that have a flexible spine, that we are more easily able to unwind and elongate with the use of the brace could see an in-brace correction of fifty percent or much more, but again, this depends on flexibility of the spine, compliance to the brace and the bony maturity of the person.
Now what?
What we have found is that depending on the flexibility of the person’s spine, bony maturity and compliance to the brace, correction will vary from person to person. If the person’s body is forced to move in a direction that is not available, the person has to compensate their body in other ways. The body is a kinetic chain and what happens at one area of the body affects the rest of the body. So it becomes imperative that the Orthotist evaluating patients for scoliosis is well-educated and experienced. Even more important is follow-up appointments. During adolescence, the human body changes a tremendous amount, but the brace does not. Custom scoliosis braces can only accommodate a certain amount of growth/change. WCR braces can accommodate between 2-3 inches of growth and approximately 15lbs of weight change. This is typical of most thermoplastic scoliosis braces. Follow-up appointments every three months will allow the Orthotist to evaluate how the body has changed within the brace and ensure that it is appropriately fitting.
I personally find it upsetting to think that a lack of their providers’ knowledge, following the “standard” of yesterday, could leave their patients with a permanent deformity. We as clinicians have learned so much about bracing for scoliosis and continue to learn more throughout time. The most important thing we can do is to continue to learn, think outside the box and measure our outcomes. Devoting time to researching is crucial to developing better orthoses for our patients that provide them with the best possible outcome.
After reading this article, please feel free to reach out with any questions or comments. I truly enjoy hearing from readers. I can be reached at julie@scoliosistherapycenters.com.
Julie McCulley
References
- Knott P, Techy F, Cotter T, Jansen L, Kove P, Loving J, Poletis K, Mardjetlko S: Retrospective analysis of immediate in-brace correction of scoliosis attainable in patients with AIS: A SOSORT initiative. Scoliosis. 2013, 8 (Suppl 1): O49
- Anahad O’Connor (October 18, 2010). “The Claim: After Being Broken, Bones Can Become Even Stronger”. New York Times. Retrieved 2010-10-19.