Revision surgery of spinal dynamic implants: a literature review and algorithm proposal

Area of Science:

• Orthopedic Surgery
• Spinal Implants
• Biomechanical Engineering

Background:

• Dynamic spinal stabilization aims to restore stability while preserving motion.
• Devices are categorized into anterior cervical, anterior lumbar, and posterior lumbar implants.
• The longevity and revision of spinal dynamic devices are critical considerations.

Purpose of the Study:

• To review dynamic spinal implants and common failure modes.
• To present clinical cases illustrating revision surgery options.
• To propose an algorithm for planning revision surgery.

Main Methods:

• Literature review of dynamic spinal implants.
• Analysis of common causes of device failure.
• Case study presentation for revision surgery.

Main Results:

• Posterior lumbar dynamic systems show revision rates of 11.3%–22.6%, peaking at 40.6% with adjacent segment disease.
• Anterior lumbar TDR revisions are most frequently due to infection and dislocations.
• Posterior pedicle screw fixation is viable for subsidence or TDR displacement.

Conclusions:

• Surgical revision of spinal dynamic implants can be challenging, particularly anterior lumbar approaches.
• Preoperative assessment of vasculature and ureters is crucial for lumbar anterior revisions.
• Restoring sagittal alignment is key in posterior spinal revision surgery.