When most parents think of sensory processing issues, they think of the children who hate clothing tags and gag on textured foods. Joint hypermobility, regardless of the reason (prematurity, Ehlers-Danlos syndrome, head injury, etc) can result in kids who stumble when they move and wobble when they rest. They are seen by orthopedists and physical therapists, and told to build up those weak muscles. Well, those kids have sensory processing issues too! And they deserve more effective treatment than they typically receive.
Lack of joint integrity, especially decreased joint stability, results in a decrease in proprioception and kinesthesia. These two under-appreciated senses tell a child about her body’s positions and movements without the use of vision. The literature out there is sparse. If you are hoping that a lot of research on this topic exists, and doctors understand why your child curls his fingers around a pencil but can squeeze the @@#$% out of clay, good luck. Most of the hard science has been done by PTs on proprioception in the leg, and there isn’t a lot of it. But OTs know a lot about the connections between sensory processing and motor performance.
Consider the process for touch-typing to better understand these senses. Your awareness of your hand’s position while at rest on the home row is proprioception. You know where your movement starting and end points are via proprioception. Your awareness of the degree of movement in a joint while typing is kinesthesia. Kinesthesia tells you that you just typed a “w” instead of an “e” without having to look at the screen or at your fingers.Your brain “knows”, through learned feedback loops, that your finger movement was too far to the left to type the letter “e”, but far enough to have been a “w”.
You are able to grade the amount of force on each key because your skin, joint and muscle sensors transmit information about the resistance you meet while pressing down each key. Your brain compares it previous typing success and the results on the screen, and makes adjustments in fractions of a second. This is sensory processing at work.
Why do children with hypermobility have proprioceptive and kinesthetic processing problems? Because information from your body is transmitted is through receptors embedded in the tissue within and surrounding the joints. These receptors respond to muscle and tendon stretch, muscle contraction, and pressure within the joint. Joint hypermobility creates less stimulation (and less accurate information) to these sensory receptors. The information coming into the brain is insufficient or delayed, and therefore the output of postural stability or dynamic movement is correspondingly poor. This shows up as a collapsed posture, difficulty quickly changing positions to catch a ball or leap over an obstacle, a heavy-footed gait, and a whole lot of other difficulties.
Can children with hypermobility improve their sensory processing and thereby improve the quality of their movements in daily life? Absolutely. Because sensory processing is a complex skill, addressing each component of functional performance will give the hypermobile child more skills. Building muscular strength within a safe range of joint movement is only one aspect of treatment. Positioning a child to give them more sensory feedback while in action is essential. Increasing overall sensory processing by using other sensory input modalities is often ignored but very helpful.
I believe that vestibular input is one of the most powerful but rarely used modalities that can improve the sensory-motor performance of hypermobile children. They don’t have to demonstrate vestibular processing deficits to benefit from a vestibular program. This program can be done without stressing fragile joints, which is a limitation for the programs that focus too much on muscular strengthening and stabilization activities.
My favorite sensory processing strategy for hypermobile kids? The use of rhythmic music during movement. Programs that use the powerful effects of sound on the brain are effective treatments for hypermobile children. It is difficult to explain to insurers and sometimes even neurologists ( don’t get me started on how hard it is for orthopedists to follow this) but if you understand the complex processes that support sensory processing, you will be changing the background music in your clinic or your home in order to capitalize on this effect!
Children with hypermobility can benefit from occupational therapy sessions that provide more than a pencil grip and a seat cushion. All it takes is an appreciation for the sensory effects of hypermobility on function.