Virginie Lafage1, Benjamin Blondel2, Justin S Smith3, Oheneba Boachie-Adjei4, Richard A Hostin5, Douglas Burton6, Gregory Mundis7, Eric Klineberg8, Christopher Ames9, Behrooz Akbarnia7, Shay Bess10, Frank Schwab11. 1. Spine Division, NYU Hospital for Joint Diseases, 306 E 15th Street, New York, NY 10003, USA. Electronic address: virginie.lafage@gmail.com. 2. Spine Division, NYU Hospital for Joint Diseases, 306 E 15th Street, New York, NY 10003, USA; Universite Aix-Marseille, Marseille, 3 Place Victor Hugo, 13331 Marseille Cédex 3, France. 3. Neurological Surgery, University of Virginia, 1215 Lee Street, Charlottesville, VA 22903, USA. 4. Orthopedic Surgery, Hospital for Special Surgery, 535 E 70th St, New York, NY 10021, USA. 5. Orthopedic Surgery, Baylor Scoliosis Center, 4708 Alliance Blvd #800, Plano, TX 75093, USA. 6. Department of Orthopedic Surgery, University of Kansas Medical Center, 3901 Rainbow Blvd, Kansas City, KS 66160, USA. 7. San Diego Center for Spinal Disorders, 4130 La Jolla Village Dr, La Jolla, CA 92037, USA. 8. Department of Orthopedic Surgery, University of California, Davis Medical Center, 2315 Stockton Blvd, Sacramento, CA 95817, USA. 9. Department of Neurological Surgery, University of California San Francisco, 505 Parnassus Ave, San Francisco, CA 94143, USA. 10. Orthopedic Center, Rocky Mountain Hospital for Children, 1719 E 19th Ave, Denver, CO 80218, USA. 11. Spine Division, NYU Hospital for Joint Diseases, 306 E 15th Street, New York, NY 10003, USA.
Abstract
STUDY DESIGN: Multicenter, retrospective radiographic analysis. OBJECTIVES: To evaluate the impact that preoperative spinopelvic parameters have on postoperative sagittal vertical axis (SVA). The researchers hypothesized that patients with a large preoperative pelvic tilt (PT) would require more extensive lumbar pedicle subtraction osteotomy (LPSO) procedures to reestablish anatomic postoperative SVA than patients with normal preoperative PT. SUMMARY OF BACKGROUND DATA: Restoration of anatomic sagittal spinal alignment has been demonstrated to improve clinical outcomes. However, the degree to which spinopelvic parameters contribute to sagittal spinal malalignment is poorly understood. METHODS: Multicenter, retrospective analysis of 183 consecutively enrolled adult spinal deformity patients treated with LPSO procedures for correction of sagittal malalignment. Preoperative and postoperative freestanding full-length sagittal X-rays were analyzed for regional curves, pelvic parameters, and global alignment. Only patients with a preoperative SVA greater than 10 cm and a postoperative SVA less than 5 cm were retained for analysis. Patients were divided into 2 groups according to preoperative PT (low PT, less than 30°; and high PT, ≥30°). Independent t test analysis was used to determine differences in correction required to achieve postoperative SVA less than 5 cm. RESULTS: A total of 55 patients were identified for analysis. Low PT (n = 30) had lower preoperative PT than high PT (n = 25; 25° vs. 42°, respectively; p < .001). Analysis of the osteotomy performed demonstrated that the high PT group required a larger osteotomy resection (30° vs. 23°; p = .039) and a larger correction of lumbar lordosis (-43° vs. -31°; p = .006) to achieve an acceptable postoperative SVA (less than 5 cm). CONCLUSIONS: This study demonstrates that patients with high PT in conjunction with sagittal spinal malalignment require larger lumbar osteotomy procedures, including a greater osteotomy resection and larger lumbar lordosis correction, to obtain a satisfactory postoperative SVA. Surgeons performing LPSO procedures must evaluate preoperative spinopelvic parameters, including PT, to avoid undercorrection and residual deformity after complex sagittal realignment procedures.
STUDY DESIGN: Multicenter, retrospective radiographic analysis. OBJECTIVES: To evaluate the impact that preoperative spinopelvic parameters have on postoperative sagittal vertical axis (SVA). The researchers hypothesized that patients with a large preoperative pelvic tilt (PT) would require more extensive lumbar pedicle subtraction osteotomy (LPSO) procedures to reestablish anatomic postoperative SVA than patients with normal preoperative PT. SUMMARY OF BACKGROUND DATA: Restoration of anatomic sagittal spinal alignment has been demonstrated to improve clinical outcomes. However, the degree to which spinopelvic parameters contribute to sagittal spinal malalignment is poorly understood. METHODS: Multicenter, retrospective analysis of 183 consecutively enrolled adult spinal deformitypatients treated with LPSO procedures for correction of sagittal malalignment. Preoperative and postoperative freestanding full-length sagittal X-rays were analyzed for regional curves, pelvic parameters, and global alignment. Only patients with a preoperative SVA greater than 10 cm and a postoperative SVA less than 5 cm were retained for analysis. Patients were divided into 2 groups according to preoperative PT (low PT, less than 30°; and high PT, ≥30°). Independent t test analysis was used to determine differences in correction required to achieve postoperative SVA less than 5 cm. RESULTS: A total of 55 patients were identified for analysis. Low PT (n = 30) had lower preoperative PT than high PT (n = 25; 25° vs. 42°, respectively; p < .001). Analysis of the osteotomy performed demonstrated that the high PT group required a larger osteotomy resection (30° vs. 23°; p = .039) and a larger correction of lumbar lordosis (-43° vs. -31°; p = .006) to achieve an acceptable postoperative SVA (less than 5 cm). CONCLUSIONS: This study demonstrates that patients with high PT in conjunction with sagittal spinal malalignment require larger lumbar osteotomy procedures, including a greater osteotomy resection and larger lumbar lordosis correction, to obtain a satisfactory postoperative SVA. Surgeons performing LPSO procedures must evaluate preoperative spinopelvic parameters, including PT, to avoid undercorrection and residual deformity after complex sagittal realignment procedures.
Authors: Marco D Burkhard; Daniel Suter; Bastian Sigrist; Philipp Fuernstahl; Mazda Farshad; José Miguel Spirig Journal: N Am Spine Soc J Date: 2021-08-29