What is upper limb pain disorder and what causes it?
Upper limb pain disorder (ULPD) is a term that was first used to describe chronic pain affecting the arm from the shoulder down to the hand. Some people use the term interchangeably with carpal tunnel syndrome (CTS). Others consider ULPD and CTS as two separate problems. The etiology or cause of ULPD remains unknown. Given a group of adults all doing the same repetitive task, over time, only some will develop ULPD. The rest will have no symptoms of any kind. Various models have been proposed to describe or explain the changes that occur. Some studies focus on psychologic and social factors. Others suggest changes in how sensory messages are processed. Research does support that some symptoms occur after pain has been present three months or more. But these late changes appear to be more related to the central nervous system than from pressure on the nerves to the arm or hand. More studies are needed to sort out the cause and effects of ULPD. Finding out which comes first: the symptoms
