How should rectal tone be documented during a digital rectal examination?

How to Document Rectal Tone

Document rectal tone by assessing and recording both resting tone and squeeze pressure of the anal sphincter using a standardized scale, evaluating the sphincter segment's baseline resistance and its augmentation during voluntary contraction, along with the puborectalis muscle function and the patient's ability to perform simulated defecation.

Structured Documentation Approach

Based on the American Gastroenterological Association guidelines 1, the digital rectal examination should systematically evaluate and document the following components:

1. Resting Tone Assessment

• Evaluate the baseline resistance of the internal anal sphincter as your finger enters the anal canal
• Document whether tone is: decreased, normal, or increased
• The resting tone reflects the internal sphincter function at baseline

2. Squeeze Pressure Assessment

• Ask the patient to squeeze as if trying to hold back stool
• Document the augmentation of pressure during this voluntary contraction
• Assess both the anal sphincter and the puborectalis muscle (located above the internal sphincter), which should contract during squeeze
• Record whether squeeze is: weak, normal, or strong

3. Simulated Defecation (Expulsion Test)

• Instruct the patient to "expel my finger" as if having a bowel movement
• This is critical for detecting defecatory disorders 1
• Document whether the patient can appropriately relax the pelvic floor or paradoxically contracts (dyssynergia)

4. Additional Pelvic Floor Assessment

• Evaluate for acute localized tenderness along the puborectalis (suggests levator ani syndrome) 1
• Assess for masses, stool consistency if present, and structural abnormalities

Standardized Scoring System

The Digital Rectal Examination Scoring System (DRESS) provides a validated quantifiable method 2:

• Use a 0-5 scale for both resting and squeeze pressure:
  • 0 = no discernible pressure
  • 3 = normal
  • 5 = extremely tight

This scoring system correlates strongly with anorectal manometry pressures (correlation coefficients of 0.82 for resting and 0.81 for squeeze) 2, making it a reliable clinical tool.

Documentation Format Example

Your note should include:

• Resting tone: Normal/decreased/increased (or DRESS score 0-5)
• Squeeze pressure: Normal/weak/strong (or DRESS score 0-5)
• Puborectalis contraction: Present/absent during squeeze
• Simulated defecation: Appropriate relaxation/paradoxical contraction/inability to expel
• Tenderness: Present/absent along puborectalis
• Structural findings: Any masses, rectocele, prolapse

Important Clinical Caveats

A normal digital rectal examination does not exclude defecatory disorders 1. The AGA guidelines explicitly state this as a strong recommendation with moderate-quality evidence. If clinical suspicion remains high despite normal findings, proceed with specialized testing such as anorectal manometry or balloon expulsion test.

While DRE by experienced examiners shows reasonable correlation with objective testing 3, studies demonstrate that accuracy in detecting abnormal tone is only about 64% 4, and correlation between different anorectal function tests is often poor 3. Therefore, when conservative treatment fails, further objective testing is warranted despite DRE findings.

The examination is most valuable when performed systematically with all three components (resting, squeeze, and expulsion), as defecatory disorders are a frequent cause of treatment failure when missed 1.