부산대학교 도서관

BACKGROUND CONTEXT Cervical deformity surgery involves various methods to achieve sagittal alignment objectives. Instrumentation type, surgical approaches, interbody grafts and osteotomies can be used to achieve surgical goals. Furthermore, patient positioning may impact ultimate sagittal correction. To our knowledge, the effect of different patient positioning methods on sagittal alignment correction after cervical deformity surgery has not been studied. PURPOSE The purpose was to examine the differences in sagittal alignment correction between three positioning methods in cervical deformity surgery. STUDY DESIGN/SETTING Retrospective review or multicenter prospective database. PATIENT SAMPLE Eighty of 153 eligible subjects from a prospective cervical deformity database. OUTCOME MEASURES Differences in cervical sagittal radiographic corrections between three types of patient positioning used in cervical deformity surgery. METHODS A review of a prospective multicenter cervical deformity database was performed. Inclusion criteria were: pre- and post-op lateral radiographs, intraop positioning data, posterior approach (with and without anterior) and UIV at C6 or above. Patients with Grade 5, 6 or 7 osteotomies were excluded. Positioning groups were Mayfield (M), Bivector traction (BV) and Halo (H). Pre- and post-op sagittal parameters were analyzed. Segmental changes were analyzed using the Fergusson method. Significance defined as a=0.05. RESULTS Eighty (58% female) of 153 potential subjects were included. Mean age was 60.6±10.5 (range 31–83) and mean BMI 29.2±8.0 (17–58). Positioning groups were 48M, 20BV, and 12H. No differences existed in baseline demographics, baseline cervical sagittal radiographic parameters, primary vs revision, UIV levels or postoperative alignment between groups. Mean cohort postoperative C2-C7 lordosis was 7.8°±14 and C2-C7 SVA was 34.1 mm±15. BV had the largest number of levels fused (BV 13.8, H 8.9, M 8.9, P<.004). There was no difference in pre-post difference of T1S, C2-C7 lordosis, C2-C7 SVA, TS-CL, C2-T3 lordosis or C2-T3 SVA between groups (P>.05). No difference existed for pre-op sagittal flexibility between groups (P>.05). There was no difference in postop alignment parameters between groups (P>.05). A trend toward smaller postop C2-T3 SVA (mm) was observed in H, however, did not reach significance (H 58, BV 73, M 84, P=.053) Examining all groups, the majority of segmental correction was achieved at C4-5-6 (Mean 6.9°±11) with no difference between groups (P>.05). M had larger segmental correction at C3-4-5 than H and BV, but not significantly different (M 7.4°, H 1.9°, BV 0.6°, P=.054). Alternatively, BV had significantly more segmental correction at C7-T1-T2 (BV 4.2°, M 0.3°, −1.7°, P<.027). No significant correlations existed between number of levels fused and segmental correction (Pearson r, P>.05). CONCLUSIONS Patient positioning does not appear to affect the amount of correction or ultimate alignment in cervical deformity procedures. All positioning methods achieve the majority of segmental correction through C4-5-6 and BV appears to have the largest corrective abilities at the cervico-thoracic junction. These findings are important to consider when planning cervical deformity procedures. [ABSTRACT FROM AUTHOR]