Joint hypermobility, also known as ligamentous laxity, is a connective tissue disorder that primarily affects the musculoskeletal system, causing ligaments, joints and other tissues to exceed the normal range of motion for that structure. People with hypermobility are naturally very flexible and can move their limbs into positions others would find somewhat difficult.
Because Hypermobility changes the way joints work together, it alters the natural mechanism of the foot. As the connective tissues in the feet are looser, there is a greater likelihood of increasing the strain on the joints and the soft tissues (the muscles, tendons and ligaments) that hold everything together. Therefore, people with joint hypermobility are more prone to having low-arched or flat feet and have a higher risk of developing problems associated with flat feet like plantar fasciitis heel pain and posterior tibial tendon dysfunction. In addition, they are more susceptible to experiencing sprains, strains and dislocations, joint instability, and poor muscle strength.