Have you ever suffered a physical injury that occurred without a traumatic impact but rather happened while you were performing routine activities? These types of injuries are quite common and it is important to understand predisposing factors in order to prevent the next incidence! There are four categories of stress that are consistently involved in these events: microtrauma, biomechanical alignment, repetitive overuse and nervous system function. In no instance is any one of these stresses found in isolation without at least one other.
Injuries to our tissues occurring on a very small scale and arise from both static postures and repetitive movements are called microtraumas. With sustained postures like sitting longer than twenty minutes, microscopic lengthening of ligaments, tendons and muscles occurs. This small- scale structural change is reversible but takes time and given the frequency that we as a population sit, it predisposes our bodies to greater damage when we move, as seen in someone experiencing severe back pain when picking a pencil up off the floor. Microtrauma from sustained positions also leads to improper joint motion due to the constant activation of certain muscle groups coincident with the lengthening of other muscle groups and ligaments. When considering how to keep our bodies healthy, this change in tissue integrity and biomechanical alignment are key contributors to unexpected injury.
Biomechanical alignment is related to joint motion, and it is relevant to injury in two ways: abnormal stress on joints and muscles as well as sub-optimal nerve function. With less-than-normal joint motion, stress and strain are placed on muscles due to abnormal muscle resting length, along with modified lines of muscle action. These alterations reduce efficiency of action, and cause compensation patterns with increasing amounts of synergist activity to complete the motion. Biomechanics also influences injury incidence through the relationships within joints of the kinetic chain. There is a pre-determined contribution from each joint that is necessary for the global movement to be completed safely, an example being an overhand throw. If the upper back is restricted while throwing, the shoulder joint will increase its motion beyond what is ideal, predisposing the shoulder joint and associated musculature to injury. Compensation patterns of muscles and joints are seen throughout the body and are significant contributors to injury development.
Our brains are outcome-oriented when it comes to coordinating movement: this means it will recruit all muscles it needs to, even if they aren’t ideally active for that specific motion. The brain is also innately wired to keep the body safe with each movement, but this component is often overridden by the goal-oriented centers: this is why we are able to continue to function, while muscles and joints exhibit dysfunction. With repetitive movement consisting of muscle and joint compensation patterns, abnormal stresses are placed on all structures involved. The effect of biomechanics, repetitive use and microtrauma compound on each other and move us to a state where overt injury is more likely.
One concept fundamental to health is that all structures and processes are governed by the nervous system, therefore nerve function is critical to safe movement. Proprioception is the sense of where our limbs are in space, and is achieved through activity of all the nerves supplying joints and muscles. Nerves pierce muscles, passing through them to reach deeper structures like ligaments as well as supplying those muscles directly; it is well documented that neurons are sensitive to pressure and lose efficiency when compressed, even minimally. In joints that aren’t moving through their full normal range, there is limited sensory feedback from that area. These areas of restriction are typically coupled with muscles that are too tight and from that apply greater pressure on nerves: these conditions reduce proprioceptive quantity and quality. When the brain doesn’t have accurate input about where the body is in space, it is not able to develop an output to the muscles that will be accurate, efficient and protect the body as it responds to its environment.
The four stressors, microtrauma, alignment, overuse and nerve function have distinct contributions to development of injury yet are clearly interdependent. It is important to understand that they occur in our bodies without our conscious awareness as each individual change is subtle and our bodies are adaptable, fluid structures. Adaptability is a tremendous asset overall, but enables these small changes to build up over time, creating layers of stress until reaching a threshold where the body loses integrity. It is important to note that these stresses are not mutually exclusive to other predisposing factors, but all four can be addressed in one simple way.
Chiropractic addresses the stressors discussed through adjustments applied to joints in the spine and limbs to release tension. An adjustment is a small amount of force applied very quickly, resulting in improvement in the amount and quality of movement. This is important to injury prevention because it corrects biomechanical misalignments and associated abnormal muscle activity as well as enhancing the quality and quantity of proprioceptive information coming from the area. Furthermore, the effect of adjusting on the body’s biomechanics mitigates the repetitive overuse compensation patterns along the kinetic chain: when all regions are moving as they were designed to, this minimizes stress through the entire body. Another benefit seen with adjustments is the activation of the nerves supplying the joint and muscles that provide its motion and leads to a reduction of muscular tension releasing pressure on the nerves. Simply, a chiropractic adjustment resets the neuromuscular system and enhances overall nerve function. As the nervous system fundamentally controls and coordinates all processes and structures in the body, when functioning optimally we respond to our environment more accurately and efficiently. Our bodies even heal faster, including healing from the chronic microtraumas we experience on a daily basis. Adjustments specifically in the neck and low back have the capacity to enhance the activity of the restoring and rejuvenating involuntary parasympathetic nervous system thereby supporting overall health! Though the root cause of injury may be complex, there is beauty in the simplicity and power of a chiropractic adjustment that restores the body back to balance and serves to prevent injury while optimizing nervous system function and overall health.
Dr. Kelsey Horsting