Articular nociceptors are primary afferent neurons in joint nerves (or primary afferent neurons supplying joints) that signal and encode the impact of noxious stimuli to joints. In the normal joint, articular nociceptors are mainly or exclusively activated by noxious mechanical stimuli applied to the joint. Articular nociceptors are sensitized for mechanical stimulation in the process of joint inflammation.
Pain in Joints
Pain in a normal joint is commonly elicited by twisting or hitting the joint. In conscious humans, pain in the normal joint can be elicited when noxious mechanical or chemical stimuli are applied to the fibrous structures, such as ligaments and fibrous capsule. No pain is elicited by stimulation of cartilage. Stimulation of normal synovial tissue rarely evokes pain. Stimulation of fibrous structures with innocuous mechanical stimulation can evoke pressure sensations.
Joint inflammation is characterized by...
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