Abdominal rigidity is stiffness of the muscles in the belly area, which can be felt when touched or pressed.

When there is a sore area in the abdomen, the pain becomes more intense as the hand presses against it and overcomes the muscular resistance.

A patient's fear or nervousness about being touched (palpated) in the abdominal area is referred to as voluntary rigidity. It usually occurs on both sides of the abdomen. Involuntary rigidity, usually caused by a physical condition, may affect one or both sides and may be associated with pain.

Nausea, vomiting, abdominal tenderness, swelling, and pain often accompany abdominal rigidity.

• Injury to the abdomen
• Peritonitis
• Acute appendicitis
• Gastrointestinal perforation
• Cholecystitis

Involuntary abdominal rigidity should always be evaluated by your health care provider.

All forms of involuntary rigidity and rebound tenderness (pain when the abdomen is gently pressed and then the pressure is suddenly released) require immediate medical attention, preferably in an emergency room. Surgery may be necessary.

You will probably be seen in an emergency room rather than at your doctor's office.

The health care provider will obtain your medical history and perform an examination. Until a diagnosis is made, pain relievers will probably not be administered because they may mask the symptoms.

Medical history questions documenting abdominal rigidity in detail may include:

• When did you first notice this symptom?
• What other symptoms are occurring at the same time? Especially, is there abdominal pain?

The physical examination may include a pelvic (and possibly a rectal) examination.

Diagnostic tests that may be performed include the following:

• Blood tests
• Urine tests
• Colonoscopy
• Gastroscopy
• Peritoneal lavage
• Stool studies
• X-ray of the chest
• X-ray of the abdomen
• Barium studies of the stomach and intestines (such as an upper GI series)