Obstructed Defecation

Understanding Obstructed Defecation

Obstructed defecation is characterised by unsatisfactory/incomplete bowel evacuation. This type of constipation is typically characterised by excessive straining to defecate or a sense of incomplete evacuation, despite normal stool type.

  • Excessive straining to defecate
  • Unsatisfactory bowel emptying
  • Abdominal bloating and discomfort
  • Nausea
  • Increased defecation frequency

The obstruction can either be functional or structural

Functional

  • Non-relaxing pelvic floor muscles
  • Dyssynergic (contracting rather than relaxing) pelvic floor muscles

Structural

  • Pelvic organ prolapse (rectocele)
  • Rectal prolapse
  • Intussusception
  • Rectal mass

The first step in diagnosis of obstructed defecation is a though history and physical examination. Further evaluation to confirm diagnosis includes

  • Defecating MRI
  • Colonoscopy
  • Functional assessment of the muscles in the anorectum via digital rectal examination and/or anorectal manometry.

Treatment of obstructed defecation often includes input from a multidisciplinary team. Common treatment options may include;

  • Adjunctive therapies utilising biofeedback (ultrasound, EMG & Rectal Balloon therapy). Biofeedback has been demonstrated to be an effective, first-line intervention for dyssynergia
  • Pelvic floor muscle (PFM) relaxation 
  • Optimising defecation technique including your toileting position, use of abdominal and pelvic floor muscles, and passive support/splinting if prolapse is relevant for you
  • Stool manipulation through changes to dietary fibre, fluid intake, and laxatives.
  • Lifestyle modifications including physical activity, weight loss, sleep hygiene, and overall relaxation
  • Surgical procedures to address structural deficits, where conservative approaches have failed.