Scoliosis is a genetic syndrome with a hallmark deformity of the spine, but it’s more than that. One way we identify genetic diseases is to study twin populations. Identical twins have the exact same genome, therefore genetic disease would be shared between the siblings, and that’s exactly what we see in scoliosis. However, these studies also show the severity of the disesse is variable, Twin studies have shown there is no question genetics play a role in developing the conditions, but differences in the direction and severity indicate there is more to it than just genetics. So what makes scoliosis get worse? Epigenetics, or factors beyond the genetics. Things like the environment and the health status of the individual. The environment can further be defined as the internal environment (metabolism) and the external environment (movement and posture). There is strong evidence that posture and movement are major factors influencing scoliosis progression. Newer science also supports hormonal, metabolic and neurological triggers involved in scoliosis progression. Our goal is to identify which trigger in which person may be a contributor to progression in that particular case. As you can imagine this is not easy to do, and requires a thorough history and exam in every case.
I recently interviewed a new patient and her family to find out her parents were encouraging her to join sports because she had recently been diagnosed with scoliosis. This is not uncommon in my practice, nor is the exact opposite, parents and doctors recommending no sports when curvatures become progressive. So which is it? Should children with scoliosis participate in sport or not? The first question that should come to mind is, what makes scoliosis curvatures progress? This is very important to understand; genetics cause the disease, and the environment is responsible for its progression. For our purposes, the “environment” is both internal (metabolism) and external (movement).
With that being said, here are few things to consider, firstly not all movement is created equal. If you think about “movement” as a large circle, then exercise is a smaller circle within that. Poor movement as well as poor postures have the potential to aggravate scoliosis, and to the contrary, movement can also be therapeutic, as is the case with good posture. Exercise is really no different, if the movements associated with the exercise are therapeutic or helpful then exercise is great, if the movements are imbalanced, limited,or unstable, then the exercise may aggravate the condition. We spend between 10 and 30 hours working on movement education with our patients. “Movement”includes exercising, as well as walking, running, stepping, sitting, standing, breathing, leaning, chewing, sitting, kneeling, lying etc.
Furthermore, exercise activates the sympathetic nervous system. Anytime you move, your sympathetic system has to dominate to bring blood to the muscles doing the work. When the sympathetics are dominating, the adrenal glands release cortisol, the heart rate becomes less variable, and digestion shuts down. Normally, the sympathetics are opposed by the parasympathic division of the autonomic nervous system, and the body returns to a state of resting and digesting. If a patient has a dominant sympathetic nervous system, it may be turned off after exercise, and lead to problems falling asleep at night (insomnia), they may be anxious, have tachycardia, have increased sweating, and decreased digestion to name a few. This is a major concern for scoliosis patients. Here’s why.
New research has identified a pathway responsible for asymmetrical bone growth related to increased sympathetic nervous system activity. Most of us are familiar with the sympathetic nervous system as the “fight or flight” division of the autonomic nervous system. Studies have shown scoliosis patients have a loss of brain influence over the sympathetics, allowing it to dominate even at rest. One way we can measure this is through the Heart Rate Variability.
Heart Rate Variability (HRV) is a measure of the balance of the sympathetic and parasympathetic influences over the heart. When the sympathetic system is dominating, the heart beat becomes less variable, meaning its rhythm becomes like clock work. This may sound good, but it’s actually not desirable because it makes the heart more susceptible to mis-beat. Studies show when athletes over train their HRV diminishes. Heart rate monitor technology allows us to easily measure the HRV allowing us to recommend rest days when exercise is leading to over training.
What is Hypothalamic Amenorrhea and how does it affect Scoliosis?
Studies confirm prolonged onset of the menstrual cycle is a risk factor for scoliosis progression. Termed Hypothalamic Amenorrhea, abnormal menses or lack menses can be caused by a lack of adequate body fat. This may be due to genetic predisposition, or due to either excessive exercise or low caloric intake. It’s important to understand why this happens. To put it simply, if the brain (hypothalamus) does not detect enough fat storage (Leptin signaling), it won’t waste energy on preparing the body for pregnancy. This can prolong the pubertal growth making these patients more susceptible to asymmetrical bone growth. Dietary and lifestyle changes should be considered in these cases. Supplementation that supports proper hormone function may reduce physiological dysfunctions associated with this condition.