Diagnosis is clinical
Progressive symptoms
Alert and able to communicate
Trismus - lockjaw (50%-75% of patients)
Sardonic smile (risus sardonicus) - other facial muscles become involved
Minor stimuli such as touch or noise start tetanic contractions
Difficulty swallowing
Long bone fractures, tendon rupture
Opisthotonus - lumbar lordosis with the neck and legs extended and the arms flexed at the elbows
Laryngospasm
Autonomic instability
Sympathetic nervous system hyperactivity, including tachycardia, sweating, arrhythmias, and hypertension
No laboratory testing is used to diagnose<unk> ; wound cultures are often negative
Alert and able to communicate
Trismus - lockjaw (50%-75% of patients)
Sardonic smile (risus sardonicus) - other facial muscles become involved
Minor stimuli such as touch or noise start tetanic contractions
Difficulty swallowing
Long bone fractures, tendon rupture
Opisthotonus - lumbar lordosis with the neck and legs extended and the arms flexed at the elbows
Laryngospasm
Autonomic instability
Sympathetic nervous system hyperactivity, including tachycardia, sweating, arrhythmias, and hypertension
Acute tetanus
Herpes zoster oticus
Akathisia
Crotaline envenomation
Conversion disorder
Herpes zoster
Drug toxicity 
Stonefish envenomation