Complications of Anterior Cervical Discectomy and Fusion (ACDF)
ACDF carries an overall complication rate of 7-19.5%, with dysphagia, postoperative hematoma, and recurrent laryngeal nerve palsy being the most common complications, while mortality remains rare at 0.1%.
Overall Complication Rates
The complication profile varies across large series, with the most comprehensive single-surgeon experience (2,579 procedures) reporting a 7.0% overall complication rate 1, while other large series report rates of 10.56% 2 to 19.3% 3. This variation likely reflects differences in complication definitions and reporting rigor rather than true outcome differences.
Intraoperative Complications
Vascular Injury
- Vertebral artery injury: Rare but potentially catastrophic
- May present with transient neuromonitoring changes intraoperatively 4
- Can lead to delayed posterior circulation stroke even without direct injury recognition 4
- Critical pitfall: Transient, lateralized IONM changes may indicate early vascular compromise requiring heightened postoperative vigilance
Dural Penetration
- Occurs in 0.5% of cases 3
- Typically manageable with primary repair and fibrin sealant
Esophageal Perforation
- Rare: 0.3% incidence 3
- Can be catastrophic if unrecognized
- Mortality occurred in 1 case (0.1%) secondary to esophageal perforation 3
- Management: Requires immediate recognition, surgical repair, broad-spectrum antibiotics, and possible diversion
Postoperative Complications
Dysphagia (Most Common)
- Incidence ranges from 1.9% 1 to 14.5% 5, with most series reporting 9.5% 3
- Transient dysphagia occurs in 18.3% of multilevel cases but resolves in most patients 6
- Only 2-3% have persistent symptoms long-term 6
- More common with multilevel procedures and anterior plating
Hematoma
- Occurs in 0.9-5.6% of cases 3, 1
- Requires surgical evacuation in approximately 2.4% of all ACDF cases 3
- Critical warning: Expanding hematoma causing airway compromise requires emergent surgical decompression
- Monitor for progressive dysphagia, dyspnea, or neck swelling in first 24 hours
Recurrent Laryngeal Nerve Palsy
- Symptomatic palsy: 3.1% 3
- Presents as hoarseness, weak voice, or aspiration risk
- Most cases resolve spontaneously within 3-6 months
- Left-sided approach may have slightly higher risk due to longer recurrent laryngeal nerve course
C5 Nerve Root Palsy
- Occurs in 0.31-3.1% of cases 7, 6
- Presents as deltoid weakness postoperatively
- Three-level ACDF has lower C5 palsy rates (0.31%) compared to corpectomy 7
- Most recover with observation and physical therapy
Hardware-Related Complications
Graft/Hardware Failure: 1.3% 1
- Includes graft dislodgment, subsidence, and plate backout
- Plate backout: 0.1% 3
- Graft dislodgment: significantly lower with ACDF versus corpectomy, especially in three-level cases 7
Pseudarthrosis: 20% in historical series 8
- Clinical significance: Strong association with persistent pain and poor outcomes 8
- 93% good/excellent outcomes with solid fusion vs. 33% pain-free with pseudarthrosis 8
- 67-70% of pseudarthrosis patients require revision surgery 8
- Plating reduces pseudarthrosis risk in single-level disease 9
Infection
- Superficial wound infection: 0.1% 3
- Deep infection/abscess: Rare but serious
- Atypical organisms possible in patients with respiratory comorbidities (e.g., Moraxella catarrhalis) 10
- Management: Surgical washout, culture-directed antibiotics, prolonged therapy
Neurological Worsening
- Worsening myelopathy: 0.2% 3
- New-onset weakness: 3% in multilevel cases 6
- Delayed vertebrobasilar stroke: Rare but devastating 4
Other Complications
- Horner's syndrome: 0.1% 3 (sympathetic chain injury)
- Cerebrospinal fluid leakage: 1.21% 7
- Neck hematoma: Distinct from airway-compromising hematoma 6
Level-Specific Considerations
Single-Level ACDF
- Lower overall complication rates
- Plating reduces pseudarthrosis but doesn't necessarily improve clinical outcomes 9
Two-Level ACDF
- Anterior plating improves arm pain compared to fusion alone 9
- Does not improve other clinical parameters
Three-Level ACDF
- ACDF superior to corpectomy for total complications, C5 palsy, infection, and graft dislodgment 7
Four-Level ACDF
- Overall complication rate acceptable with 88.3% symptom improvement 6
- Fusion rate: 95% 6
- Early dysphagia in 18.3%, but only 3.3% persistent 6
Risk Mitigation Strategies
Preoperative:
- Vascular imaging (CTA/MRA) in patients with vascular risk factors before multilevel ACDF 4
- Optimize comorbidities, especially respiratory disease
Intraoperative:
- Meticulous hemostasis before closure
- Careful retractor placement and periodic release to minimize dysphagia
- Recognize and respond to IONM changes immediately 4
- Stay midline to avoid vertebral artery and sympathetic chain
Postoperative:
- Monitor airway closely first 24 hours
- Low threshold for imaging if progressive dysphagia or neurological changes
- Early mobilization and swallowing therapy for dysphagia
Key Clinical Pearls
- Dysphagia is the most common complication but usually transient
- Hematoma requiring evacuation occurs in ~2.4% and is a surgical emergency
- Pseudarthrosis strongly correlates with poor outcomes and need for revision 8
- Transient IONM changes warrant heightened stroke vigilance postoperatively 4
- ACDF has lower total complications than corpectomy for multilevel disease 7