Diaphragmatic Injury
Frequently missed — CXR sensitivity 40–60%, collar sign on CT, and surgical repair principles.
Overview
Diaphragmatic injury occurs in approximately 1–7% of blunt trauma patients and up to 15% of penetrating thoracoabdominal trauma. It is frequently missed in the acute setting — clinical awareness and a high index of suspicion are essential. Small penetrating injuries in particular may remain clinically silent for months to years before presenting with intestinal obstruction or strangulation as a chronic traumatic hernia.
Mechanisms and laterality
Left-sided injuries are approximately 3 times more common than right-sided — the liver provides a protective buttress to the right hemidiaphragm during blunt trauma, distributing force over a wider area. Left-sided injuries are more likely to allow immediate herniation of abdominal viscera.
Diagnosis
CXR sensitivity for diaphragm rupture is only 40–60% — a normal CXR does not exclude injury. CT sensitivity is better but still misses up to 30% of injuries, particularly small penetrating defects and right-sided tears. Diagnostic laparoscopy is the gold standard when imaging is inconclusive in a haemodynamically stable patient.
- CXR: elevated hemidiaphragm · stomach or bowel loops in chest · nasogastric tube coiled in chest · contralateral mediastinal shift
- CT chest/abdomen: Investigation of choice in stable patients. Specific signs: collar sign (waist-like constriction of herniated bowel at the defect) · dependent viscera sign (posteriorly displaced viscera resting against the posterior chest wall — pathognomonic for left-sided rupture) · direct visualisation of diaphragmatic discontinuity
- MRI: Most sensitive for diaphragm injuries but impractical in acute trauma — useful for delayed or chronic presentation
- Diagnostic laparoscopy: Directly visualises both hemidiaphragms; allows simultaneous repair; indicated when CT is inconclusive in a haemodynamically stable patient
Classification by timing
- Acute (<24 hours): diagnosed at initial trauma assessment or laparotomy for associated injuries
- Subacute (24 hours – 7 days): identified during hospitalisation after missed initial diagnosis
- Chronic / delayed (>7 days): presents months to years after injury with obstruction, strangulation, or incidental imaging finding — most dangerous due to adhesions between herniated viscera and pleura
Management
Diaphragmatic injury is rarely isolated. Haemorrhage control and management of life-threatening associated injuries take absolute priority over diaphragm repair. A temporary delay in diaphragm repair does not worsen outcome — the diaphragm can be repaired safely once the patient is stabilised.
Surgical approach
| Clinical setting | Preferred approach |
|---|---|
| Haemodynamically unstable ± abdominal injury | Laparotomy — rapid access; control haemorrhage; repair diaphragm at same sitting |
| Stable; left-sided blunt injury | Laparotomy or laparoscopy |
| Isolated right-sided injury | Right thoracotomy — better access to right hemidiaphragm; reduces liver interference |
| Chronic traumatic hernia | Thoracotomy — adhesions between herniated viscera and pleura require careful sharp dissection; direct visualisation essential |
Repair principles
- Primary repair with non-absorbable sutures (polyprolene or braided polyester) — interrupted horizontal mattress technique; full-thickness bites are essential
- Tension-free closure is mandatory — a tight repair will dehisce
- Large defects: prosthetic mesh (PTFE or polyprolene) — avoids tension; allows reconstruction of significant tissue loss
- Diaphragmatic flap (phrenoplasty): pedicled diaphragmatic flap for closure of oesophageal defects and bronchial stump buttress — excellent vascularity makes it ideal for contaminated or irradiated fields
Reconstruction is indicated when resection results in: a defect >50% of the hemidiaphragm · inability to achieve primary closure without tension · large anterior defects. Primary closure with non-absorbable sutures for small defects. Synthetic mesh (PTFE or polyprolene) for large defects. Biological mesh is preferred in infected or contaminated fields. After reconstruction, place a chest drain on the ipsilateral side.
All clinical content should be verified against current guidelines before clinical application. This resource is intended for revision and educational purposes only.
Standard textbooks
- Shields TW, LoCicero J, Reed CE, Feins RH. General Thoracic Surgery. 7th ed. Lippincott Williams & Wilkins.
- Sellke FW, del Nido PJ, Swanson SJ. Sabiston & Spencer Surgery of the Chest. 9th ed. Elsevier.
- Pearson FG, et al. Thoracic Surgery. 3rd ed. Churchill Livingstone.