air, airway, airways, all, asphyxia, back, backbone, backs, blockage, blockages, blocked, blocking, blocks, bone, bones, choking, column, columns, complete, deprivation, descriptions, exudate, first, flow, hemorrhagic, impair, impaired, impairing, impede, impeded, impedes, impeding, inflamed, inflammation, l, l-3, l-4, l-5, l3, l4, l5, lack, lining, low, lower, lumbar, medical, mucus, multiple, o2, occluded, occluding, occlusions, operation, operations, operative, oxygen, passages, periods, plug, procedure, procedures, purulence, purulent, regular, remain, sagittal, spinal, spine, spines, spinous, steps, subtitle, suffocate, suffocation, surgeries, surgery, surgical, tissue, tissues, trachea, tracheal, tracheas, tracheotomy, ultimate, vertebra, vertebrae, vertebral, ways, widespread, 3, 4, 5