As they worked, he walked around, correcting the placement of limbs and joints.

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

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For the survivors, decades of coping with stunted, twisted or missing limbs has meant greater wear and tear on remaining joints and muscles, and virtually guaranteed the premature onset of arthritis and chronic pain.

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However, the prolonged immobility of joints associated with wheelchair use can worsen contractures, in which the limbs draw inward and become fixed in that position.

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