Sacral malformations: use of imaging to optimise sacral nerve stimulation

Area of Science:

• Radiology
• Anatomy
• Neurosurgery

Background:

• Sacral nerve stimulation (SNS) is a common treatment for pelvic floor disorders.
• Successful SNS depends on accurate electrode placement through sacral foramina.
• Sacral anomalies can complicate electrode placement, impacting treatment success.

Purpose of the Study:

• To determine the incidence of congenital sacral malformations.
• To understand how these malformations affect sacral anatomy.
• To improve sacral nerve stimulation electrode placement by understanding common sacral anomalies.

Main Methods:

• Retrospective review of 998 consecutive MRI scans.
• Scans were performed for low back pain investigation in patients with prior CT/X-ray.
• Analysis focused on identifying and categorizing sacral malformations.

Main Results:

• Congenital sacral malformations were identified in 24.1% of patients.
• The most common malformations were sacral meningeal cysts (16%) and spina bifida occulta (9.9%).
• Other identified malformations included transitional vertebrae, anterior occult meningocele, partial sacral agenesis, and S1 vertebral dysplasia.

Conclusions:

• Sacral malformations are common, often asymptomatic.
• Surgeons performing SNS require knowledge of sacral malformations and their impact on foraminal anatomy.
• Pre-procedural imaging is crucial for planning successful SNS electrode placement.