Presentation Description: Title: Head Fixation and Positioning in Neurosurgery Description: This presentation delves into the critical aspects of head fixation and positioning in neurosurgery, highlighting the importance of precise and stable positioning for successful surgical outcomes. It covers various techniques and devices used to immobilize the head during cranial procedures, ensuring optimal access to the surgical site while minimizing risks of complications. Key topics include the principles of patient positioning, types of head fixation devices, and best practices for different neurosurgical approaches. The presentation also addresses potential complications and strategies to mitigate them, emphasizing the role of a multidisciplinary team in achieving patient safety and surgical efficacy.

1. Basics of Head Fixation and
Positioning
Dhaval Shukla
Additional Professor of Neurosurgery
NIMHANS, Bangalore.

2. Basic Principles of Head Fixation

4. Basic Principles of Head Fixation
Falling into the pins
• Firm placement of the two-
point swivel arm before
engaging a contralateral single
pin
• Spatial positioning of the pins
relative to the cranial equator
and gravity
• Ensure that two of the three pins
are below the cranial equator
• Insuring that the cranium will be
held safely even if the pins were
to be less tight than optimal
• Tightness of the pins
• Pressure for adults 60 - 80 lbs
• Pressure for children 30 - 40 lbs
Coppa ND, et al. AANS 2010.

5. Basic Principles of Head Fixation
Avoid
• Critical neurovascular structures
• superficial temporal artery
• supraorbital artery and nerve
• occipital artery
• Areas of thin bone
• Squamous temporal
• Regions with underlying venous
structures
• Air sinuses
• Pins in children less than 3 years of
age
Coppa ND, et al. AANS 2010.

6. Bifrontal Craniotomy
• All 3 pins below equator
• Approximate position of
ears
• Double pin
• One on mastoid process
• Other superiorly and
toward midline
• Single pin superior and
posterior to the pinna of
the contralateral ear
Coppa ND, et al. AANS 2010.

7. Pterional Craniotomy
• Pterion facing upward
• Two pins at or below
equator
• Double pins
• One pin just superior and
lateral to the occipital
protuberance, below
equator
• Other pin on mastoid
process ipsilateral to the
side of surgical approach
• Single pin superior to the
temporal fossa
(contralateral to surgical
approach) Coppa ND, et al. AANS 2010.

8. Middle Fossa Craniotomy
• Double pins
• Superior to occipital
protuberance, which
indicates the, and on
either side of superior
sagittal sinus and superior
to transverse sinuses
• Single pin
• Should be located at or
near midline several
centimeters above nasion
Coppa ND, et al. AANS 2010.

9. Prone Craniotomy
• Double pins
• One pin is posterior and
superior to the pinna
• Other pin is anterior in
relation to the temporal
fossa, and should be at or
near margin of this fossa
• Single pin
• Superior to the pinna of
the contralateral ear at
the margin of the
temporal fossa
• Place single pin on right
side to reduce risk to
language area
Coppa ND, et al. AANS 2010.

10. Positioning in Neurosurgery

11. Positioning in Neurosurgery
Garg N, Indira Devi B, Shukla D. Positioning in Neurosurgery.
Ramamurthi and Tandon’s Textbook of Neurosurgery (3rd ed.). 2012. pp 2299-2305.
Proper positioning
To provide an adequate exposure of the operative site
without excessive retraction of the brain.
• Operative site should be easily accessible
• Operative field should be least dependent
• Area should also have a direct line of sight
• Reduce venous congestion and oozing, thus providing a
bloodless field
• The operative field should be at a higher position than the heart
• No pressure on the neck and no compression of the abdomen while
the patient is in the prone position
• Making use of gravity to help in retracting the brain

12. Positioning in Neurosurgery
Garg N, Indira Devi B, Shukla D. Positioning in Neurosurgery.
Ramamurthi and Tandon’s Textbook of Neurosurgery (3rd ed.). 2012. pp 2299-2305.
Proper positioning
• To make surgery ergonomical and less tiring for
surgeon.
• To ensure patient safety and comfort, so as to
reduce the post-operative discomfort of the patient.
Avoid undue pressure/ traction of limbs
Avoid undue pressure on vital tissues
• To permit free access to the anaesthetist.
• To permit extension of the operative field if
required.

20. • Preoperative Assessment
• When judged appropriate, it is helpful to ascertain that
patients can comfortably tolerate the anticipated
operative position.
• Protective Padding
• Padded armboards may decrease the risk of upper
extremity neuropathy.
• The use of chest rolls in laterally positioned patients may
decrease the risk of upper extremity neuropathies.
• Padding at the elbow and at the fibular head may
decrease the risk of upper and lower extremity
neuropathies, respectively.
• Equipment
• Shoulder braces in steep head-down positions may
increase the risk of brachial plexus neuropathies.
Prevention of Perioperative Peripheral Neuropathies
ASA. Practice Advisory for the Prevention of Perioperative Peripheral Neuropathies.
Anesthesiology 2000;92:1168–1182.

21. • Upper Extremity Positioning
• Arm abduction < 90° in supine patient
• Patients who are positioned prone may comfortably
tolerate arm abduction > 90°
• Arms should be positioned to decrease pressure on
ulnar groove
• When arms are tucked at the side, a neutral forearm
position is recommended
• When arms are abducted on armboards, either
supination or a neutral forearm position is acceptable
• Prolonged pressure on the radial nerve in the spiral
groove of the humerus should be avoided
• Extension of the elbow beyond a comfortable range may
stretch the median nerve
Prevention of Perioperative Peripheral Neuropathies
ASA. Practice Advisory for the Prevention of Perioperative Peripheral Neuropathies.
Anesthesiology 2000;92:1168–1182.

22. • Lower Extremity Positioning
• Prolonged pressure on the peroneal nerve at the fibular
head should be avoided.
• Neither extension nor flexion of the hip increases the
risk of femoral neuropathy
• Postoperative Assessment
• A simple postoperative assessment of extremity nerve
function may lead to early recognition of peripheral
neuropathies.
• Documentation
• Charting specific positioning actions during the care of
patients may result in improvements of care
Prevention of Perioperative Peripheral Neuropathies
ASA. Practice Advisory for the Prevention of Perioperative Peripheral Neuropathies.
Anesthesiology 2000;92:1168–1182.

23. Take Home Message
• Positioning is the joint responsibility of the surgeon
and anesthesiologist.
• Each member of the team has to use knowledge of
anatomy and physiology, as well as experience in
using various positioning aids and accessories, to
the safe positioning of patients.