Indications Indications subaxial cervical fractures with malalignment unilateral and bilateral facet dislocations displaced odontoid fractures select hangman's fractures C1-2 rotatory subluxation Contraindications patient who is not awake, alert, and cooperative presence of a skull fracture may be a contraindication Patient position Preferred setting emergency room, operating room, ICU for close observation and frequent fluoroscopy/radiographs Patient position supine with reverse trendelenburg or use of arm and leg weights can help prevent patient migration to the top of the bed with addition of weights. Sedation small doses of diazepam can be administered to aid in muscle relaxation however patient must remain awake and able to converse Pin Placement Pin placement (Gardner-Wells pins) pin placement is 1 cm above pinna, in line with external auditory meatus and below the equator of the skull. if the pin is placed too anterior, the temporalis muscles and superficial temporal artery and vein are at risk an anterior pin will apply an extension moment to the cervical spine if the pin is placed too posterior, it can apply a flexion moment to the cervical spine. a posterior pin with a flexion moment may facilitate reduction of a facet dislocation. Pin tightness On Gardner-Wells tongs, pins are tightened until spring loaded indicator protrudes 1 mm above surface this is the equivalent of 139 newtons (31 lbs) of force overtightening by 0.3 mm leads to 448 newtons (100 lbs) failure of temporal bone occurs at 965 +/- 200 newtons (216 lbs) note Mayfield pins are tightened to 60 lbs overtightening of the pins can result in penetration of the inner table of the calvarium this may cause cerebral hemorrhage or abscess Pin strength stainless steel pins have higher failure loads than titanium and MRI-compatible graphite and should be used with traction of > 50lbs. Reduction with Serial Traction Serial traction an initial 10lbs is added. weights are increased by 10lb increments every 20 minutes serial exams and radiographs are taken after each weight is placed maximal weight is controversial some authors recommend weight limits of 70 lbs recent studies report that up to 140 lbs is safe Reduction maneuvers reduction of a unilateral facet dislocation reduction maneuver performed after facet is distracted to a perched position maintain axial load and rotate head 30-40 degrees past midline, in the direction of the dislocation stop once resistance is felt, and confirm with radiographs reduction of bilateral facet dislocation reduction maneuver performed after facet is distracted to a perched position palpate the stepoff in the spinal process posteriorly and apply an anterior directed force caudal to the level of the dislocation rotate the head 40 degrees beyond midline in one direction, and then rotate 40 degrees in the other direction while axial traction is maintained. Complications Failure to reduce a bilateral, irreducible facet dislocation is unstable and should be treatment with urgent open reduction after an MRI is performed.. Change in neurologic exam with any change in the neurologic exam the weights should be removed and an MRI should be obtained.