Why do patients develop dysphagia after anterior cervical discectomy and fusion (ACDF) for cervical spinal stenosis?

From the Guidelines

Patients develop dysphagia after anterior cervical ectomy for cervical spinal stenosis primarily due to the increased risk of aspiration associated with the surgical procedure, as evidenced by a study that found 42% of patients undergoing anterior cervical operations aspirated after the procedure 1.

Causes of Dysphagia

The development of dysphagia in these patients can be attributed to several factors, including:

• Soft tissue swelling and inflammation around the esophagus and pharynx as a response to surgical manipulation
• Retraction of the esophagus and trachea during surgery causing temporary nerve irritation, particularly affecting the recurrent laryngeal nerve and pharyngeal plexus
• Hardware placement, such as plates and screws used for fusion, creating mechanical pressure on the esophagus
• Hematoma formation or postoperative infection exacerbating swallowing difficulties

Aspiration Risk

As noted in the study, cervical spinal surgery can increase aspiration risk, with 42% of patients undergoing anterior cervical operations aspirating after the procedure 1. This highlights the importance of identifying and managing aspiration risk in patients undergoing anterior cervical ectomy for cervical spinal stenosis.

Management

Management of post-operative dysphagia typically includes conservative measures such as:

• Dietary modifications (soft foods)
• Proper positioning during eating
• Swallowing therapy exercises Severe or persistent dysphagia may require further evaluation with imaging or endoscopy to rule out hardware complications or other structural issues requiring intervention.

From the Research

Causes of Dysphagia after Anterior Cervical Ectomy

• Dysphagia is a common complication of anterior cervical decompression and fusion (ACDF) surgery, with an incidence rate of up to 71% within the first two weeks after surgery 2.
• The causes of dysphagia after ACDF surgery are multifactorial, and may include:
  • Multilevel cervical spine and upper cervical spine surgeries 3, 2.
  • Oesophageal retraction, prominence of the cervical plate, and prevertebral swelling 2.
  • Expulsion of bone cement used in the surgery, which can compress the esophagus 4.
• Risk factors for postoperative dysphagia include:
  • Female gender, advanced age, multilevel surgery, longer operating time, and severe pre-operative neck pain 2, 5.
  • Revision surgery and the use of recombinant human bone morphogenetic protein in routine anterior cervical spine surgery 5.

Prevention and Treatment of Dysphagia

• Preoperative measures to prevent dysphagia include performing tracheal exercises before the surgical procedure 5.
• Intraoperative measures to prevent dysphagia include:
  • Avoiding a prolonged operative time 5.
  • Using small and smoother cervical plates, and anchored spacers instead of plates 5.
  • Applying steroid before wound closure, and performing arthroplasty instead of anterior cervical fusion for one-level disease 5.
• Treatment of dysphagia after ACDF surgery may include the use of nasogastric-tube feeding, and home care services 6.

Incidence and Outcomes of Dysphagia

• The incidence of persistent dysphagia requiring nasogastric-tube feeding after ACDF surgery is higher in elderly patients (aged 70 years and over) 6.
• The overall incidence rate of dysphagia after ACDF surgery is approximately 2.3%, with the highest incidence rates occurring within the first three months after surgery 6.
• The risks of dysphagia and the necessity of using home care services are higher in elderly patients, with a hazard ratio of 2.69 and 4.96, respectively 6.