The eight carpal bones of the wrist (“carpus”) are held together by ligaments. When there is an injury to a ligament (ranging from an isolated sprain to a catastrophic dislocation) the wrist may be rendered unstable.
Carpal ligament injuries can lead to post-traumatic arthritis because the bones of the carpus are normally “intercalated,” that is, tightly tethered to each other. When a carpal ligament is injured, the bones may not move in their normal concerted fashion. This abnormal motion leads to abnormal positioning of the bones and, in turn, overloading of the joint surfaces.
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