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Hypermobility: Taking Control of Unstable Joints

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In a recent study looking at people with hypermobile spectrum disorder and shoulder discomfort, the researchers found that light resistance training was just as effective as heavy resistance training for reducing shoulder discomfort and improving shoulder function.[1]

These findings ring true to my clinical experiences. For example, I have worked with hypermobile people with a lot of shoulder strength and perfect strength training technique yet frequent shoulder dislocations and I have worked with young hypermobile dancers with very little muscle bulk around their shoulders, yet no shoulder problems despite performing extreme shoulder movements.  I suspect that while strength is important for joint stability, the most relevant elements of symptomatic shoulder instability are impaired proprioception and injury.

Proprioception is a word used to describe our awareness of our body’s position, movement, effort, and balance. [2] Proprioception results from mechanoreceptors sending signals from our joints and muscles to our brain (figure 1). 

      Figure 1. A schematic diagram of mechanoreceptors sending proprioceptive information to the brain (Song, 2021, p. 586)

      Joints have four known types of mechanoreceptors that tell the brain about changes in joint position and pressure (figure 2). [3] As these receptors are triggered by stretch, having loose joints can slow the onset and intensity of the signal being sent to the brain.  This reduced signal means the brain is less aware of what is happening at the joint.

      A schematic diagram of four joint mechanoreceptors

      Figure 2. A schematic diagram of four joint mechanoreceptors (Salamanna, 2023, p. 2)

      Fortunately for people with joint hypermobility, muscles are a bigger contributor to proprioception than joints. [2] Proprioceptive information from muscle is not related to strength, but rather comes from sensory receptors in the muscle called muscle spindles and Golgi Tendon Organs (GTO). [5]

      A schematic diagram illustrating the neural pathway of the muscle spindle and the golgi tendon organ to the brain

      Figure 2. A schematic diagram illustrating the neural pathway of the muscle spindle and the golgi tendon organ to the brain (Haggie, 2023, p. 4)

      Research has found that you can improve your proprioception with practice. [6, 7, 8, 9]  The elements of practice that help improve proprioception include:

      • mental focus on the movement you hope to improve
      • Visual, auditory, and or touch feedback (to confirm the movement has been performed as expected)
      • Movement specificity (improvement is specific to speed, angle, load, and whether it is an open or closed kinetic chain movement)
      • Reward (achieving the objective activates reward circuitry in the brain which reinforces the “rewiring” in the brain)
      • Frequency (the more you practice the better you get). 

      I will highlight how these elements tie together by comparing the proprioceptive elements of a woman’s shoulder while dancing to her shoulder while performing push-ups. 

      • Dancing

      A woman stands in front of a YouTube recording of a choreographer performing a dance. She watches the choreography and mentally rehearses the movements. She practices the first eight steps intensely thinking about the path, speed, and final placement of her body as she performs a variety of movements. She then steps in front of a mirror for visual feedback on her movements.

      Once she feels she can perform the first eight steps of the dance routine accurately, she plays some music and focuses on moving her body and hitting her mark on the beat. She practices the eight steps both watching and not watching herself in the mirror to the beat of the music. Once she has learnt the first eight steps, she moves to the next eight steps and then repeats the above process for the combined 16 steps. She uses this learning process to gradually add more of the choreography. She practices the dance for 30 minutes.

      In this example we can see the dancer has practiced many elements of shoulder proprioception. She has focused on the intricacy and aesthetic of her arm movement. She has received visual feedback through the mirror and auditory feedback when she hits her mark on the beat. She has moved her arm in a variety of ways under varying loads (the faster she moves and the more extended her arm the more load there is on her shoulder). The movements are open (meaning her hands are free) enabling her to improve her shoulder control in less stable and more function positions. Her arm moves in concert with her body. She is rewarded for her efforts as she sees her performance improve in the mirror. She performs many repetitions throughout the 30 minute dance session.

      • Push-ups

      In contrast to the dancing, let’s look at the woman performing push-ups.

      The woman kneels to the floor and places her hands on the floor in front of her. She slowly lowers her chest to the floor and then presses her body away from the floor. She repeats this same movement 10 times until her shoulders feel tired and she can no longer control the movement. After a minute of rest, she repeats the same procedure for six more repetitions.

      In this push-up scenario the woman’s focus is on the effort she is placing through her hands and the movement of her body relative to the floor.  Her visual feedback is how close her face is to the floor. The push-up is a very specific task. The hands are planted (closed kinetic chain), the body is rigid, and the movement is slow.  As she “feels the burn” in her muscles she feels the sense of achievement which is rewarding. Because the muscles become fatigued, she can only perform a limited number of repetitions. 

      When we compare these two activities, it is clear that the dancing provides more stimuli to improve shoulder proprioception than the push-ups. Given science has shown proprioception is more relevant to joint control than strength, it seems reasonable to assume the dancing will be a better choice for enhancing shoulder stability.

      That being said, while proprioception is more important than strength at maintaining shoulder control, the push-up can play a very helpful role in recovering from injury. The role of injury in joint control and the rehabilitation of an injury is a topic for another blog.

      Want to read more of Aaron’s articles on EDS, click here.

      1. Liaghat B, Juul-Kristensen B, Faber DA, Christensen EO, Søgaard K, Skou ST, Søndergaard J, Juhl CB. One-year effectiveness of high-load compared with low-load strengthening exercise on self-reported function in patients with hypermobile shoulders: a secondary analysis from a randomised controlled trial. Br J Sports Med. 2024 Mar 21;58(7):373-381. doi: 10.1136/bjsports-2023-107563. PMID: 38253436; PMCID: PMC10982631.
      2. Haggie L, Schmid L, Röhrle O, Besier T, McMorland A and Saini H (2023), Linking cortex and contraction—Integrating models along the corticomuscular pathway. Front. Physiol. 14:1095260. doi: 10.3389/fphys.2023.1095260
      3. Salamanna, F., Caravelli, S., Marchese, L., Carniato, M., Vocale, E., Gardini, G., Puccetti, G., Mosca, M., & Giavaresi, G. (2023). Proprioception and Mechanoreceptors in Osteoarthritis: A Systematic Literature Review. Journal of clinical medicine12(20), 6623. https://doi.org/10.3390/jcm12206623
      4. Song, Q., Zhang, X., Mao, M., Sun, W., Zhang, C., Chen, Y., & Li, L. (2021). Relationship of proprioception, cutaneous sensitivity, and muscle strength with the balance control among older adults. Journal of sport and health science10(5), 585–593. https://doi.org/10.1016/j.jshs.2021.07.005
      5. SLICE Science (2023, September 8). Proprioception: The Real 6th sense. YouTube. https://www.youtube.com/watch?v=s412XZGOeYU
      6. Aman, J. E., Elangovan, N., Yeh, I. L., & Konczak, J. (2015). The effectiveness of proprioceptive training for improving motor function: a systematic review. Frontiers in human neuroscience8, 1075. https://doi.org/10.3389/fnhum.2014.01075
      7. Han, J., Waddington, G., Adams, R., Anson, J., & Liu, Y. (2016). Assessing proprioception: A critical review of methods. Journal of sport and health science5(1), 80–90. https://doi.org/10.1016/j.jshs.2014.10.004
      8. Rossi, C., Bastian, A. J., & Therrien, A. S. (2021). Mechanisms of proprioceptive realignment in human motor learning. Current Opinion in Physiology20, 186-197. https://doi.org/10.1016/j.cophys.2021.01.011
      9. Therrien, A. S., & Wong, A. L. (2022). Mechanisms of Human Motor Learning Do Not Function Independently. Frontiers in human neuroscience15, 785992. https://doi.org/10.3389/fnhum.2021.785992

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