How do you assess for rebound tenderness in a patient?

How to Assess for Rebound Tenderness

Rebound tenderness is assessed by applying gentle, steady pressure to the abdomen (typically over the area of concern such as McBurney's point in suspected appendicitis), holding for a few seconds, then quickly releasing the pressure—a positive test occurs when the patient experiences sharp pain upon release rather than during compression. 1

Standard Technique

• Apply gentle, steady pressure with your hand to the area of suspected peritoneal inflammation, holding for several seconds 2, 1
• Quickly withdraw your hand and observe the patient's response 1
• Positive test: Sharp pain occurs when pressure is released (indicating peritoneal irritation) 2, 1
• Negative test: No increased pain or only mild discomfort upon release 1

Alternative Technique: "Pinch-an-Inch" Test

For patients who may not tolerate traditional rebound testing or when you want to minimize discomfort:

• Grasp a fold of abdominal skin over the area of concern (e.g., McBurney's point) and elevate it away from the peritoneum 3
• Allow the skin to recoil back briskly against the peritoneum 3
• Positive test: Increased pain when the skin fold strikes the peritoneum, indicating peritonitis is likely present 3
• This technique may be less uncomfortable than traditional rebound testing while still detecting peritoneal irritation 3

Clinical Context and Interpretation

When to Assess

• Rebound tenderness should be assessed in patients with acute abdominal pain, suspected appendicitis, peritonitis, or intra-abdominal infection 2, 1
• In suspected appendicitis, combine with other findings: fever, migratory pain to right lower quadrant, positive psoas sign 1
• In suspected spontaneous bacterial peritonitis (cirrhosis patients), assess for abdominal pain, tenderness on palpation with or without rebound tenderness, and ileus 2

Diagnostic Performance

• Sensitivity ranges from 78-95% for acute appendicitis, making it reasonably good at detecting peritonitis when present 4, 5
• Specificity is poor (48-60%), leading to many false positive results 4
• Positive predictive value is limited, but it has the highest negative predictive value (81.3%) among physical signs for appendicitis 5
• Rebound tenderness has the highest positive predictive value (65%) for complicated appendicitis in children 1

Critical Caveats and Pitfalls

Test Limitations

• Rebound tenderness inflicts significant discomfort to patients and should be performed judiciously 4
• Low specificity means it cannot confirm diagnosis alone—must be combined with other clinical findings, laboratory tests (WBC, CRP), and imaging 1, 4
• Little additional value when local tenderness or rigidity is already present 4

Special Populations

• Elderly or unconscious patients may have minimal signs despite severe disease, making physical examination unreliable 6
• Up to one-third of patients with spontaneous bacterial peritonitis may be entirely asymptomatic or present only with encephalopathy and acute kidney injury 2
• Approximately 5% of patients with intestinal perforation remain asymptomatic despite serious pathology 6

When Physical Examination Is Insufficient

• Do not rely on rebound tenderness alone to make surgical decisions 1, 4
• For intermediate clinical suspicion, obtain CT abdomen/pelvis with IV contrast (adults) or ultrasound (children) rather than proceeding based on examination alone 1
• In elderly patients with suspected appendicitis, CT scan with IV contrast is strongly recommended due to higher rates of complicated disease and atypical presentations 1
• Deterioration despite seemingly appropriate management should prompt reassessment for alternative diagnoses 7

Integration with Clinical Decision-Making

• Combine rebound tenderness with other findings: guarding, rigidity, Rovsing's sign, fever, leukocytosis, and elevated CRP 1, 5
• Use validated scoring systems (e.g., Alvarado score) that incorporate rebound tenderness (1 point) along with other clinical and laboratory parameters 8
• Physical examination findings must guide risk stratification into low, intermediate, or high probability categories to determine need for imaging versus observation versus surgical consultation 1