Myotomy

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Myotomy for Upper Gastrointestinal Tract Sphincters

Myotomy is a surgical technique involving the deliberate cutting of muscular sphincters within the upper gastrointestinal (GI) tract to relieve abnormal tightness and restore normal swallowing and gastric transit. These procedures are primarily used in the management of motility disorders—conditions where failure of relaxation causes obstruction to bolus passage.

They may be used on the Upper Oesophageal Sphincter to aid swallowing, Lower Oesophageal Sphincter to aid motility of the food boluses into the stomach and the pyloric sphincter to help with slow stomach emptying (gastroparesis).

Physiological Rationale

Impaired relaxation, often due to neuromuscular dysfunction, can lead to dysphagia, retrosternal pressure or pain, regurgitation, and secondary malnutrition. By performing a controlled division of the muscle fibres, myotomy reduces outflow resistance and can dramatically improve symptoms.

Lower Oesophageal Sphincter Myotomy

The LOS is the most common target for therapeutic myotomy.

Indications

• Achalasia (all subtypes)

• Other oesophagogastric junction outflow obstructions

• Non-relaxing hypertensive LOS resistant to medical therapy

Techniques

Heller Myotomy

A laparoscopic approach whereby the distal oesophageal and proximal gastric circular muscle layers are incised longitudinally. Usually combined with a partial fundoplication (e.g., Dor or Toupet) to reduce risk of post-operative gastro-oesophageal reflux due to reduced barrier pressure.

Per-Oral Endoscopic Myotomy (POEM)

A more recent endoscopic intervention pioneered in the 2010s:

1. Mucosal entry is created within the oesophagus.

2. A submucosal tunnel is dissected, providing access to the LES muscle.

3. Selective myotomy of the circular muscle fibres is performed.

4. The mucosal entry site is sealed with clips.

Advantages

• Scarless access (no external incisions)

• Effective in all subtypes of achalasia, including spastic forms

• Longer myotomy possible if necessary (e.g., for oesophageal spasm)

Considerations

• Higher likelihood of post-operative reflux compared to Heller + fundoplication (as there is no anatomical anti-reflux reconstruction)

• Requires specialised expertise and advanced endoscopic capability

Upper Oesophageal Sphincter (Cricopharyngeal) Myotomy

Targeted at the cricopharyngeus muscle within the UOS.

Indications

• Cricopharyngeal achalasia

• Dysphagia related to Zenker’s diverticulum

• Neuromuscular dysphagia when the UOS obstructs bolus transit

Techniques

• Open myotomy through a cervical approach

• Endoscopic stapler-assisted diverticulotomy (Zenker’s)

• Laser endoscopic myotomy

Risks

• Aspiration if incompetence becomes excessive

• Vocal cord injury via proximity to recurrent laryngeal nerve

Pyloric Sphincter Myotomy

Indications

Gastropareis causing

• Nausea and vomiting

•     Bloating

•     Early satiety (feeling full quickly)

•     Upper abdominal pain

•    Erratic blood sugar levels

•    Reflux

Although this may be achieved laparoscopically it is more likely to be performed using G-POEM, (Gastric Peroral Endoscopic Myotomy) cutting the muscle of the pyloric sphincter, the valve between the stomach and small intestine that is often tight in patients with this condition. The procedure involves creating a tunnel inside the stomach wall to access and cut the muscle fibers, which helps to relieve symptoms and improve gastric emptying.  

Post-Surgical Considerations

Functional Outcomes

Most patients experience notable improvement in swallowing and reduction in oesophageal pressure. However:

• Reflux is a common long-term concern—particularly after LES myotomy without a wrap (e.g., POEM).

• Some may develop oesophagitis requiring long-term acid suppression therapy.

• Myotomy does not treat underlying motor degeneration (e.g., in achalasia), so disease progression is still possible.

Follow-Up

• Symptom monitoring

• High-resolution manometry and pH impedance testing for reflux assessment

Page updated 3 December 2025