Lockjaw (trismus) is a painful condition that limits your ability to open your mouth all the way. It occurs when the muscles you use to chew spasm, meaning they can’t relax completely. The term ...

How to stop lockjaw depends on its cause. Lockjaw, also known as trismus, is not always caused by tetanus. It can also result from trauma, temporomandibular joint (TMJ) disorders, oral infections, or ...

The human mouth primarily functions with the help of the temporomandibular joints, or the TMJs. These are complex sliding hinge joints on both sides of the face that connect the lower jaw to the skull ...

Adrenaline increases the "alertness" of the nervous system, meaning it's ready to trigger muscle contraction. It also increases the amount of blood flow and changes the tension of the muscles, which, ...

Infectious agents can cause muscle twitching and spasms, too. The most commonly known is probably tetanus, which causes a phenomenon called lockjaw, where the neck and jaw muscles contract to the ...