CARs to Retrain body Maps
Controlled Articular Rotations (CARs) offer a physical approach to "rewiring" the brain's understanding of joint movement. When a person experiences injury, pain, or even long periods of immobility, the brain and body's communication around movement becomes disrupted. The lack of motion can lead to reduced confidence in movement, compensation patterns, or even fear of exploring certain ranges of motion. CARs are a gradual, systematic way to re-establish joint function and recalibrate the brain's perception of safe and functional movement.
Exploring Movement Boundaries
Cervical Spine controlled articular rotations (CARs)
In CARs, the patient or client takes each joint through its entire range of motion in a rotational manner, deliberately engaging muscles and tissues to ensure controlled and active movement. CARs can be done passively during the initial rehabilitation and retraining phase by a practitioner to help guide the person through the movement. Passive CARs also give the practitioner a better understanding of what the joint can do by feeling where the tissue tension lies and where the movement restrictions exist. This exploration of boundaries is key to the rewiring process. As the joint moves through different angles and degrees of motion, the brain continually receives feedback from proprioceptors in the joint and surrounding tissues. This feedback teaches the brain where the true boundaries of movement lie. Over time, this process helps the individual recognize the difference between protective "limits" set by the brain (often influenced by pain or fear) and the actual physical limits of their joint mobility.
When individuals explore these boundaries through CARs, they begin to increase their "movement confidence." By gradually and safely pushing their joints to the edges of their ranges, they start to understand the integrity of their joints and feel more secure in extending their movements beyond previously self-imposed limits. For example, a person may hesitate to lift their arm past a certain height after a shoulder injury. CARs, through their controlled nature, help to reintegrate and confirm the entire capacity of movement, allowing them to expand their functional range confidently.
The red portion of the heat map indicates the zone of the hip being used for different movements. It is evident that only a small portion of the joint is utilized during daily tasks. Thus, the importance of exploring the joints full capabilities on a regular basis.
Perceived Space vs. Actual Space
The brain creates a "map" of the body in space—a representation of where the limbs, joints, and body parts are at any given time. When joint movement is compromised, this map becomes smudged. The perceived space in which an individual feels they can safely move is often much smaller than their actual range of motion. CARs provide a systematic way to recalibrate this map.
After an injury the brain does not see itself clearly. When a joint has a movement restriction the information the brain receives has a lower resolution than when the joint is healthy with full range of motion.
Patients can extend their perceived and actual range of motion by consistently engaging in controlled, deliberate movements. For example, after an ankle sprain, the brain might perceive the ankle's range as limited, signaling the body to stop movement prematurely due to fear of re-injury. CARs help progressively expand this perceived "space" by exposing the joint to its full range, giving the brain a new understanding of its safe boundaries. As this perceived space expands, so does the confidence to engage in previously avoided activities due to fear of pain or re-injury.
Neural Adaptation Through Safe, Controlled Movement
One of the most important aspects of CARs is that they are low-risk and controlled, allowing patients to explore their movement potential without placing undue stress on healing tissues. This safe environment is essential for neural adaptation. The nervous system is susceptible to perceived threats, and sudden, uncontrolled movements can trigger protective responses, such as muscle guarding or pain. By maintaining control throughout the rotation, CARs provide a non-threatening signal to the nervous system, encouraging it to allow greater freedom of movement.
This low-risk, high-control environment allows for gradual adaptation. As the nervous system becomes accustomed to the demands of controlled articular rotations, it begins to "relearn" the true capacity of the joint. This process of neural adaptation is not just about muscle flexibility or strength—it's about retraining the brain to permit movement and recalibrate its safety mechanisms.
Expanding the "Workspace" for Movement
The goal of CARs, particularly in a rehabilitative or training context, is not just to restore the joint's passive range of motion but to expand the active "workspace" of movement. Active workspace is the range in which the individual can move, exert force, and maintain control. Pushing the outer boundaries of joint motion in a controlled, gradual manner, CARs increase the usable range in which an individual can function. Increasing the usable ROM is particularly important for athletes or individuals with high movement demands, as having a greater active workspace reduces the risk of injury and improves overall performance.
A graphical representation of the cervical spine workspace
Movement efficiency improves as the nervous system becomes more comfortable with these newly acquired ranges. The individual can engage in more complex movements with better control, reduced compensatory strategies, and greater functional capacity. CARs are not just about mobility; they are about creating a robust, adaptable system where the brain and body work harmoniously to optimize joint health and movement potential.
A Safe Gateway to Progressive Loading
For rehabilitation patients or anyone recovering from injury, CARs offer a safe, progressive entry point to regaining strength and mobility. Because they can be controlled and pain-free, CARs allow patients to explore movements that might initially feel risky without the fear of causing further damage. Over time, as movement boundaries are safely pushed and expanded, these rotations can serve as a foundation for adding more load and complexity to the joint.
For example, in early rehabilitation, CARs might be performed slowly and with minimal irradiation or tension. As the patient's confidence and joint capacity grow, more irradiation can gradually be introduced along with increased speed and intensity of the movements, further driving neural and tissue adaptation. This progressive approach helps build a more resilient joint while reinforcing the brain's understanding of its movement potential.
Summary: CARs as a Cognitive and Physical Tool for Rewiring
Controlled articular rotations (CARs) represent the intersection of movement and neurology. They allow individuals to explore and reclaim their movement boundaries while driving neural adaptations that enhance proprioception, control, and joint health. The deliberate, controlled nature of CARs offers a safe way to expand both perceived and actual ranges of motion, allowing patients and athletes alike to improve their joint function and overall movement quality progressively.
The better a joint functions, the brighter the spotlight shines. High joint functionality results in clear afferent information to the brain. The brain receives higher-resolution afferent information, leading to faster and stronger efferent (motor) responses. The feedback mechanisms provide the highest resolution and clarity when the joint has the appropriate workspace.
In essence, CARs act as a physical tool for cognitive rewiring, giving patients the confidence and capability to move freely and safely while fostering a deeper understanding of how their body moves in space. This expanded "workspace" of movement lays the foundation for improved mobility, strength, and resilience—making CARs an essential practice for anyone looking to maintain or enhance joint health and functional capacity.
