Scoliosis X-rays and Your Brace: How Long Should the Brace Be off Before Your Next Scoliosis X-Ray (or MRI)?
A common practice in scoliosis management is to measure the progress of the scoliosis curve by taking a full spine X-ray. When a patient wears a scoliosis brace, they will typically be instructed by the orthopedic surgeon to take it off for 24 hours prior to receiving their next X-ray. But what should we do if you are supposed to be wearing the brace 23 hours per day? Will it harm the spine or jeopardize treatment effectiveness to be out of brace 24 hours for your next X-ray? If you wear your brace and only take it off just before your X-ray, how will we know the true condition of the scoliosis?
24 Hours Out-of-Brace Is NOT Universally Accepted by Doctors
These are questions and concerns pondered primarily by non-surgical scoliosis care providers. For example, one doctor may request only in-brace imaging, and forego the out-of-brace altogether. Others may do both an in-brace and out-of-brace on the same day, and yet others will instruct the patient to be out-of-brace before their scoliosis X-ray only as long as their maximum allowed time out of brace(1). For example, if a patient is allowed to be out of the brace up to 2 hours per day, then an image is taken after 2 hours out of brace. This practice is in opposition to the standard orthopedic request for all scoliosis X-rays to be 24 hours out of brace.
Why 24 Hours Out-of-Brace May Be Harmful
To understand the importance of time out of brace, it helps to understand what a brace does and how it works. A key problem with scoliosis is that soft-tissue grows short on the concave side of the curve and grows long on the convex side. The short tissue must be stretched longer, but the long tissue must be made shorter again. It is easy to imagine ways to stretch shortened tissue, but how do you get overstretched tissue such as ligaments and discs to shorten back to their normal length?
We can’t just shorten the elongated convex side for a few minutes and expect it to stay. Not even hours or weeks of holding the elongated tissue short will make it change shape. Typically it takes months of holding the over-stretched, elongated soft tissue into a shortened position in order for ligaments to return to their normal, shorter length. In order to cause over-stretched tissue to return to its normal length, it must be held short 24/7 for months on end.
For permanent change to occur, the elongated side of the curve must be held short and never allowed to return to a stretched position. If, for example, a patient wears a brace 18 hours per day but then spends 6 hours per day collapsing back into their scoliosis curve with harmful activities, the ligaments that were overstretched will continue to become overstretched. The time out of brace undoes the progress made from wearing the brace. This is one of the main reasons why we believe that a brace should be worn 23+ hours per day for optimum success. Any time allowing the over-stretched soft tissue to be stretched again will prevent progress in reducing the curve.
Like Orthodontics for the Spine
This is no different than what an orthodontist would require of a patient wearing braces on teeth. No one would take the braces off in 6 months and say, “Let’s check to see if the teeth are still straight after 2 weeks without braces”. We already know the answer to that question: The teeth would be unable to hold their newly aligned position because ligaments are still too long on one side of the tooth and too short on the other side. The imbalance in the ligament tension would tug on the tooth until it returned back to its previously misaligned position.
Rather than taking braces off every 6 months to measure progress, we all know that the braces must stay on for 1-2 years, sometimes more. Furthermore, once braces come off, a retainer must be worn. First, the retainer has to be worn 24 hours per day, then time is reduced until the patient is just wearing it at night. Many patients continue to wear their retainer at night into early adulthood to assure alignment is not lost. Why should we treat the alignment of the spine any differently than the alignment of teeth? If anything, spinal alignment is a far more complicated and unstable thing than a tooth, and, therefore, should be treated with even greater care.
It is for this reason that we keep our patients in their braces 23 hours per day for the first 1-2 years, or until the end of growth. We do NOT instruct them to discontinue wearing the brace 24 hours prior to X-rays or standing MRI during the first 1-2 years (we’ve replaced X-ray with radiation-free standing MRI). However, once the person’s curve has reduced, the reduction has been held over time, and skeletal maturity nears, only then do we begin instructing our patients to go longer periods without the brace.
When a patient is ready to reduce time in the brace, we will instruct them to remain out-of-brace for progressively longer periods of time prior to taking a standing MRI of the scoliosis. In such cases, we may exceed the 24-hour recommendation, and test the patient for 1 week, or even 1 month out of the brace. This allows us to carefully assess the stability of their straighter spine. The results from such an approach have been highly rewarding, providing lasting reductions of scoliotic curves.
1. Knott P, Pappo E, Cameron M, et al. SOSORT 2012 consensus paper: reducing x-ray exposure in pediatric patients with scoliosis. Scoliosis 2014;9:4.