Should We Label All Synovial Cysts as Unstable?

Area of Science:

• Neurosurgery
• Spinal Surgery
• Radiology

Background:

• Lumbar intra spinal cysts (LISCs) can cause segmental instability.
• Assessing anatomical parameters is crucial for surgical planning.
• Understanding LISC-related instability guides treatment decisions.

Purpose of the Study:

• To analyze anatomical parameters influencing segmental stability in LISC patients.
• To evaluate the outcomes of microscopic unilateral laminotomy and cystectomy for LISCs.
• To correlate radiological findings with clinical outcomes.

Main Methods:

• Retrospective review of 30 LISC patients surgically managed between 2007-2013.
• Evaluation of segmental mobility, angulation, facet inclination, and disc degeneration on MRI and dynamic radiographs.
• Assessment of outcomes using Visual Analogue Score (VAS), Oswestry Disability Index (ODI), and Macnab criteria.

Main Results:

• Significant improvement in VAS and ODI scores postoperatively.
• No postoperative instability observed in patients treated with unilateral laminotomy and cystectomy.
• Facet angle averaged 42.6 degrees; disc degeneration stages varied.
• Mean follow-up was 46.5 months.

Conclusions:

• Coronal facet inclination and absence of radiological instability suggest adequate residual stability.
• Stand-alone decompression for LISCs without instability yields sustained good/excellent outcomes.
• Spinal fusion is recommended for LISCs with associated instability.