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Updated: Feb 2, 2026

Anterior Cervical Discectomy and Fusion in the Ovine Model
Published on: October 5, 2009
Stand-Alone Cervical Cages in 2-Level Anterior Interbody Fusion in Cervical Spondylotic Myelopathy: Results from a
Eugene Pak-Lin Ng1, Andrew Siu-Leung Yip1, Keith Hay-Man Wan1
1Department of Orthopaedics and Traumatology, Kwong Wah Hospital, Hong Kong.
Study Design:
A retrospective review of patients who underwent 2-level anterior cervical discectomy and fusion (ACDF) with standalone polyetheretherketone (PEEK) cages for cervical spondylotic myelopathy (CSM).
Purpose:
To evaluate the efficacy of stand-alone PEEK cage in 2-level cervical interbody fusion for CSM.
Overview Of Literature:
ACDF is a standard surgical procedure to treat degenerative disc disease. However, the use of additional anterior plating for 2-level ACDF remains controversial.
Methods:
We reviewed outcomes of patients who underwent 2-level ACDF with stand-alone PEEK cages for CSM over a 7-year period (2007-2015) in a regional hospital. Japanese Orthopaedic Association (JOA) score, fusion rate, subsidence rate, cage migration, and cervical alignment by the C2-7 angle as well as the local segmental angle (LSA) of the cervical spine were assessed.
Results:
In total, 31 patients (mean age, 59 years; range, 36-87 years) underwent 2-level ACDF with a cage-only construct procedure between 2007 and 2015. The minimum follow-up was 24 months; mean follow-up was 51 months. C3-5 fusion was performed in 45%, C4-6 fusion in 32%, and C5-7 fusion in 23%. Mean JOA score improved from 10.1±2.2 to 13.9±2.1 (p<0.01) at the 24-month follow-up. Fusion was achieved in all patients. Subsidence occurred in 22.5% of the cages but was not associated with differences in JOA scores, age, sex, or levels fused. Lordosis of the C2-7 angle and LSA increased after surgery, which were maintained for up to 1 year but subsequently disappeared after 2 years, yet the difference was not statistically significant. No cage migration was noted; two patients developed adjacent segment disease requiring posterior laminoplasty 3 years after ACDF.
Conclusions:
The use of a stand-alone PEEK cage in a 2-level cervical interbody fusion achieves satisfactory improvements in both clinical outcomes and fusion.
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