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My Routine

Sagittal Plane

Count the interspinous spaces

Choose the largest ligamentum flavum

Mark the level of insertionDirection of insertion

Transverse Plane

MidlineDirection of insertion

“All in one” View

Position Patient

Pre -scan

• Discussion with patient

• Ultrasound machine

• Curvilinear Obstetric probe (5-2MHz)

• Obstetric settings

• Depth 9-13cm

• Position the patient

• Sagittal Plane - Counting Levels.

• Start midline or just paramedian

• Sacrum is the only long flat bone, followed by a long shadow

• Ligamentum flavum is a window to the anterior wall of the canal, which is bone followed by a shadow

• Lamina is bone, followed by a shadow.

• Slowly and carefully scan up the back, counting levels.

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Sacrum

Anterior wall of canal

Ligamentum flavum

Lamina

• Sagittal Plane - Choose the larger ligamentum flavum

• The size of the ligamentum flavum determines how much of the anterior wall can be seen.

• Small probe movments and angulations are needed to optimise the views of the anterior wall of the canal.

Anterior wall of canal

Ligamentum flavum

Lamina

• Sagittal Plane - Mark the level of insertion & determine the Direction of insertion in the sagittal plane

• “Heel Toe” the probe so the canal is horizontal across the screen.

• Move the probe so the ligamentum flavum of choice is in the middle of the screen

• Mark the back at the middle of the probe.

• The direction of the handle is the direction to advance the needle in the sagittal plane

Anterior wall of canal

Lamina

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• Transverse Plane - Midline and the direction of insertion• The easiest and probably most valuable view

• Adjust the probe so the ultrasound image has - the spinous process shadow in the middle of the screen and so symmetrical anatomy is at an equal depth

• Then the middle of the probe is over the spinous process and the direction of the handle is the direction to advance the needle in the transverse plane.

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• Transverse Plane - “All in one view”• Validated in published research• Scan slowly up and down the back to visualise the anterior wall of the spinal

canal. In this position there is no bone between the probe and the ligamentum flavum.

• Recheck (mark) midline and level of insertion. The angle of the probe is the direction to pass the needle in both the sagittal and transverse plane.

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Anterior wall of spinal canal

Anterior wall of canal

Performing the Epidural

• Position the patient as you scanned the patient

• Use your routine clinical skills

• Palpate

• Long needle for local anaesthetic