For years, people with foot or ankle problems have been prescribed "rocker shoes, " in which the soles curve like the bottom of a rocking chair to transfer the workload away from joints and bones.

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Some have longer limbs, denser bones, slipperier tendons and double joints.

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My long bones in my arms and legs felt like someone was ramming a long steel rod into them, my joints all creaked and popped in and out and ached like the worst arthritis ever. my skin was on fire and my extremities, especially my hands and feet, where it seemed to concentrate.

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