Skull Clamp Safety: Complications, Risk Controls and a Pre-Incision Checklist

Skull clamp complications to know

The risks reported with pin-type head fixation include scalp laceration at the pin sites, skull penetration or fracture, particularly in infants, elderly patients and thin or diseased bone, epidural or subgaleal haematoma at a pin site, pin-site infection, and, in rare cases, nerve or vascular injury. In the sitting position and with the head above the heart, venous air embolism is a recognised concern, and pin placement and positioning are part of the risk discussion.

Most of these events are linked to excessive or uneven pin force, poor pin placement, or movement of the patient against a clamp that is not fully secured. Prevention therefore starts before the clamp is opened.

Head pin slippage and how to prevent it

Head pin slippage happens when pin force is too low for the load, when pins are placed on a sloping or thin area of bone, or when the patient is moved after fixation. A slipping pin can scratch the scalp or release the head from the clamp at a critical moment, which is why some systems add a secondary safeguard.

For example, the DORO QR3 XTom system for small-gantry CT comes with a dedicated torque screwdriver for setting pin pressure and a U-Belt that acts as a safety net in the unlikely event of head slippage. The DORO Multi-Purpose Skull Clamp offers an optional 90 N torque screw for finer control of lower pin forces, which is useful for children and fragile bone.

Skull pin injury: pin choice and force

Use pins appropriate to the patient. Paediatric pin holders and non-invasive gel set-ups exist because adult pin force is not suitable for a thin skull; for infants, the safest choice may be to avoid pins altogether, see paediatric head fixation. Never reuse a pin that is designed for single use, and inspect reusable pins for damage.

In imaging cases, disposable radiolucent pins such as those used with the DORO LUCENT Headrest System combine low artefact with a fresh sharp tip for every patient. Always follow the force values and pin positions given in the instructions for use of your clamp.

Reading the IFU: Mayfield skull clamp IFU and others

Whether you use a Mayfield skull clamp or a DORO clamp, the instructions for use define the allowed pin forces, the pin sites to avoid, the maximum load, the compatible accessories and the reprocessing steps. Make sure the IFU is available in the theatre, in a language the team reads, and that new staff are trained on it.

Pin placement itself is covered in Mayfield head holder pin placement. Avoid temporal bone, thin areas over sinuses, shunts and burr holes, and keep the pins roughly opposite each other so that force is balanced.

A pre-incision checklist

Run a short, spoken check after the final position is set and before the drapes go on. Assign one person to own it, and record the pin force and pin sites in the OR record.

Beckfinity supplies DORO head fixation with documentation for training; to arrange a demonstration for your team, contact us.

• Clamp and pins correct for patient age and bone quality
• Pin sites checked and pin force set and verified
• All table, base and swivel locks tight, with the table not moved after fixation
• Navigation and retractor arms mounted on the clamp rail, not on the patient
• Eyes, ears and airway accessible; venous air embolism plan agreed if the head is elevated
• Emergency head-release procedure known to the whole team