BACKGROUND: Loss of @entity717 and lateral bending after atlantoaxial fusion reduces a @entity1 's quality of life. Therefore, effective, nonfusion fixation alternatives are needed for @entity8432 . OBJECTIVE: To evaluate the initial stability and function of posterior atlantoaxial restricted nonfusion fixation (PAARNF), a new protocol, using cadaveric cervical spines compared with the intact state, destabilization, and posterior C1-C2 rod fixation. METHODS: Cervical areas C0 through C3 were used from 6 cadaveric spines to test flexion-extension, lateral bending, and @entity717 (ROM). With the use of a machine, 1.5-Nm torque at a rate of 0.1 Nm/s was used and held for 10 seconds. The specimens were loaded 3 times, and data were collected in the third cycle and tested in the following sequence: (1) intact, (2) destabilization (using a type II odontoid @entity174 model), (3) destabilization with PAARNF (PAARNF group), and (4) rod implantation (rod group). The order of tests for the PAARNF and rod groups was randomly assigned. RESULTS: The average flexion-extension ROM in the PAARNF group was 7.44    2.05  , which was significantly less than in the intact (P = .00) and destabilization (P = .00) groups but not significantly different from that of the rod group (P = .07). The average lateral bending ROM (10.59    2.33  ; P = .00) and @entity717 ROM (38.79    13.41  ; P = .00) of the PAARNF group were significantly greater than in the rod group. However, the values of the PAARNF group showed no significant differences compared with those of the intact group. CONCLUSION: PAARNF restricted @entity9807 but preserved @entity717 and lateral bending at the atlantoaxial joint in a type II odontoid @entity174 model. However, it should not be used clinically until further studies have been performed to test the long-term effects of this procedure. ABBREVIATIONS: PAARNF, posterior atlantoaxial restricted nonfusion fixationROM, range of motion.

New Posterior Atlantoaxial Restricted Non-Fusion Fixation for XXXX : A Biomechanical Study.

@entity1 :: ('9606', 'Species') :: ['patient'] @entity8432 :: ('MESH:C563472', 'Disease') :: ['atlantoaxial instability'] @entity174 :: ('MESH:D050723', 'Disease') :: ['fracture'] @entity717 :: ('MESH:D009069', 'Disease') :: ['axial rotation range of motion', 'axial rotation'] @entity9807 :: ('MESH:C538196', 'Disease') :: ['atlantoaxial flexion-extension']
@entity8432 :: (MESH:C563472,Disease) :: ['Atlantoaxial Instability']
