How does the Malone procedure channel work and does patient stool come from it?

How the Malone Procedure Channel Works for Stool Management

The Malone procedure creates a surgically-constructed channel through which antegrade colonic enemas are administered to empty the colorectum, allowing stool to be evacuated through the normal anal pathway, not through the Malone channel itself. 1

Mechanism and Function of the Malone Procedure

• The Malone Antegrade Continence Enema (MACE or ACE) procedure creates a small stoma on the abdomen that provides catheterizable access to the colon 1
• The procedure typically uses the appendix to create this channel, though alternative techniques like ileal neoappendicostomy or the Macedo-Malone procedure may be used when the appendix is unavailable 2, 3
• The channel allows for administration of enemas in an antegrade fashion (from above), which is more effective than traditional retrograde enemas for certain patients 1
• Patients or caregivers insert a catheter through the stoma to deliver cleansing solution directly into the colon 1

Stool Pathway and Common Misconception

• Important clarification: Stool does NOT exit through the Malone channel; it continues to exit through the patient's rectum and anus 1
• The Malone channel is only for administering the cleansing solution, not for stool evacuation 4
• After the enema solution is administered through the Malone channel, it stimulates colonic contractions and softens stool, facilitating evacuation through the normal anatomical route 1

Clinical Applications and Patient Selection

• The procedure is primarily indicated for patients with:
  • Fecal incontinence unresponsive to medical management 1
  • Intractable constipation when other therapies have failed 4
  • Neurogenic bowel dysfunction (e.g., spina bifida, myelomeningocele) 1
• The procedure is considered when retrograde enemas or other conservative measures have proven ineffective 1

Practical Considerations and Limitations

• Administration of antegrade enemas via the Malone procedure typically takes 20-60 minutes 1
• The procedure requires significant patient or caregiver commitment to regular use 1
• Complications are common and include:
  • Stomal stenosis (narrowing of the opening) in approximately 24% of patients 5
  • Stomal leakage in approximately 28% of patients 5
  • Need for surgical revision in over 50% of patients within 3 years 1
• Success rates vary by population:
  • Approximately 80% of children achieve complete or near-complete fecal continence 1
  • Only about 50% of adults show significant improvement 1, 6

Surgical Variations

• Several surgical techniques exist for creating the Malone channel:
  • Traditional appendicostomy (using the appendix) 2
  • Ileal neoappendicostomy (creating a channel from ileum) - preferred in adults due to lower complication rates 2
  • Macedo-Malone procedure (using left colon without requiring the appendix) 3, 7

The Malone procedure represents an important surgical option for managing severe constipation and fecal incontinence, but patients should understand that it creates an access channel for administering enemas, not an alternative pathway for stool evacuation 1.