Clinical Outcomes Following Three- and Four-Level Anterior Cervical Discectomy and Fusion: A Systematic Review and...

Area of Science:

• Neurosurgery
• Orthopedic Surgery
• Spinal Surgery

Background:

• Anterior cervical discectomy and fusion (ACDF) is a standard treatment for cervical spine degeneration.
• While 1- and 2-level ACDF yield good results, longer constructs may have poorer outcomes.
• Emerging data suggest 4-level ACDF might be riskier than 3-level ACDF, yet they are often grouped.

Purpose of the Study:

• To systematically review and meta-analyze outcomes comparing 3-level and 4-level ACDF.
• To identify differences in patient-reported outcomes, perioperative characteristics, and fusion/complication rates.

Main Methods:

• Systematic literature search of MEDLINE, Embase, and Cochrane databases following PRISMA guidelines.
• Inclusion of studies reporting outcomes for 3- or 4-level ACDF; exclusion of complex etiology and registry studies.
• Meta-analysis using random-effects models for continuous (Cohen's d) and dichotomous (log odds ratios) outcomes.

Main Results:

• Both 3- and 4-level ACDF improved pain, disability, and neurologic function.
• Four-level ACDF demonstrated less improvement in axial neck pain and lower fusion rates.
• Four-level ACDF was associated with longer operative times, increased blood loss, and longer hospital stays.

Conclusions:

• Both 3- and 4-level ACDF effectively treat degenerative cervical pathology.
• Four-level ACDF is linked to inferior neck pain relief, reduced fusion success, and higher perioperative morbidity.
• These findings highlight significant differences crucial for surgical decision-making and patient counseling.