Does zero-profile anchored cage accompanied by a higher postoperative subsidence compared with cage-plate construct?...

Area of Science:

• Spine surgery
• Orthopedic biomechanics
• Neurosurgery

Background:

• Anterior cervical discectomy and fusion (ACDF) commonly utilizes implants to achieve spinal stability.
• The zero-profile anchored cage (ZP) is increasingly adopted for ACDF due to lower dysphagia rates.
• Controversy exists regarding the comparative stability and subsidence risk between ZP and traditional cage-plate constructs (CP).

Purpose of the Study:

• To compare the postoperative subsidence rates between ZP and CP implants in ACDF.
• To evaluate the influence of implant type on spinal fusion stability and patient outcomes.
• To determine if ZP devices present a higher incidence of subsidence compared to CP constructs.

Main Methods:

• A systematic meta-analysis was conducted, adhering to PRISMA guidelines.
• PubMed and Embase databases were searched to identify relevant comparative studies.
• Ten trials involving 626 patients were analyzed for clinical and radiological outcomes, including subsidence rates.

Main Results:

• The overall incidence of postoperative subsidence was significantly higher in the ZP group (15.1%) compared to the CP group (8.8%).
• Subgroup analysis revealed no significant difference in subsidence for single-level fusions, but a significantly higher rate for ZP in multilevel (≥2 levels) fusions.
• While ZP showed a higher subsidence rate, it was associated with less intraoperative blood loss, shorter operation time, and lower dysphagia incidence compared to CP.

Conclusions:

• Zero-profile anchored cages (ZP) may be associated with an increased risk of postoperative subsidence, particularly in multilevel ACDF procedures.
• Despite higher subsidence rates, ZP implants offer benefits such as reduced dysphagia and potentially shorter operation times.
• Further high-quality, multicenter randomized controlled trials are warranted to validate these findings and guide clinical practice.