Satoshi Nori1, Tateru Shiraishi2, Ryoma Aoyama3, Ken Ninomiya3, Junichi Yamane4, Kazuya Kitamura5, Seiji Ueda6. 1. Department of Orthopedic Surgery, Tokyo Dental College Ichikawa General Hospital, 5-11-13 Sugano, Ichikawa, Chiba, 272-8513, Japan. satoshi_nori@2003.jukuin.keio.ac.jp. 2. Shiraishi Spine Clinic, Tokyo, Japan. 3. Department of Orthopedic Surgery, Tokyo Dental College Ichikawa General Hospital, 5-11-13 Sugano, Ichikawa, Chiba, 272-8513, Japan. 4. Department of Orthopedic Surgery, National Hospital Organization Murayama Medical Center, Musashimurayama, Tokyo, Japan. 5. Department of Orthopedic Surgery, Saiseikai Yokohamashi Tobu Hospital, Yokohama, Kanagawa, Japan. 6. Department of Orthopedic Surgery, Kawasaki Municipal Hospital, Kawasaki, Kanagawa, Japan.
Abstract
PURPOSE: A high C7 slope induces C2-C7 lordosis to compensate for cervical sagittal balance adjustments. A muscle-preserving selective laminectomy (SL) can maintain this compensation postoperatively. This study evaluated the effect of an extremely high C7 slope on C2-C7 lordotic compensation following SL. METHODS: This study enrolled 151 cervical compressive myelopathy patients who underwent SL. Lateral cervical spine radiographs were taken before surgery and during final follow-up. Patients were divided into extremely high C7 slope (≥ 30°) (EH) and non-high C7 slope (< 30°) (NH) groups and the influence of a high C7 slope on radiological and surgical outcomes was examined. RESULTS: Mean age was higher in group EH (p < 0.001). Preoperatively, patients in group EH had a larger C2-C7 sagittal vertical axis (SVA) (p = 0.001) and greater cervical lordosis (p < 0.001). Although C2-C7 SVA increased after surgery, mean C2-C7 angle of group EH decreased. Mismatches between C7 slope and C2-C7 angle increased for group EH postoperatively (p = 0.015). Postoperative Japanese Orthopedic Association (JOA) score and recovery rate (RR) were slightly lower in group EH (p = 0.001 and p = 0.006, respectively). Multiple linear regression analyses revealed that extremely high C7 slope, not age, affected the RR of JOA score (p = 0.006). CONCLUSIONS: Patients in group EH were older and had highly compensated cervical sagittal alignment preoperatively. They demonstrated postoperative cervical sagittal balance mismatch increases and slightly worse functional recovery. An extremely high C7 slope limited compensatory cervical lordosis following SL. These slides can be retrieved under Electronic Supplementary Material.
PURPOSE: A high C7 slope induces C2-C7 lordosis to compensate for cervical sagittal balance adjustments. A muscle-preserving selective laminectomy (SL) can maintain this compensation postoperatively. This study evaluated the effect of an extremely high C7 slope on C2-C7 lordotic compensation following SL. METHODS: This study enrolled 151 cervical compressive myelopathypatients who underwent SL. Lateral cervical spine radiographs were taken before surgery and during final follow-up. Patients were divided into extremely high C7 slope (≥ 30°) (EH) and non-high C7 slope (< 30°) (NH) groups and the influence of a high C7 slope on radiological and surgical outcomes was examined. RESULTS: Mean age was higher in group EH (p < 0.001). Preoperatively, patients in group EH had a larger C2-C7 sagittal vertical axis (SVA) (p = 0.001) and greater cervical lordosis (p < 0.001). Although C2-C7 SVA increased after surgery, mean C2-C7 angle of group EH decreased. Mismatches between C7 slope and C2-C7 angle increased for group EH postoperatively (p = 0.015). Postoperative Japanese Orthopedic Association (JOA) score and recovery rate (RR) were slightly lower in group EH (p = 0.001 and p = 0.006, respectively). Multiple linear regression analyses revealed that extremely high C7 slope, not age, affected the RR of JOA score (p = 0.006). CONCLUSIONS:Patients in group EH were older and had highly compensated cervical sagittal alignment preoperatively. They demonstrated postoperative cervical sagittal balance mismatch increases and slightly worse functional recovery. An extremely high C7 slope limited compensatory cervical lordosis following SL. These slides can be retrieved under Electronic Supplementary Material.
Authors: Christopher P Ames; Justin S Smith; Robert Eastlack; Donald J Blaskiewicz; Christopher I Shaffrey; Frank Schwab; Shay Bess; Han Jo Kim; Gregory M Mundis; Eric Klineberg; Munish Gupta; Michael O'Brien; Richard Hostin; Justin K Scheer; Themistocles S Protopsaltis; Kai-Ming G Fu; Robert Hart; Todd J Albert; K Daniel Riew; Michael G Fehlings; Vedat Deviren; Virginie Lafage Journal: J Neurosurg Spine Date: 2015-08-14
Authors: Themistocles S Protopsaltis; Justin K Scheer; Jamie S Terran; Justin S Smith; D Kojo Hamilton; Han Jo Kim; Greg M Mundis; Robert A Hart; Ian M McCarthy; Eric Klineberg; Virginie Lafage; Shay Bess; Frank Schwab; Christopher I Shaffrey; Christopher P Ames Journal: J Neurosurg Spine Date: 2015-05-15
Authors: Jessica A Tang; Justin K Scheer; Justin S Smith; Vedat Deviren; Shay Bess; Robert A Hart; Virginie Lafage; Christopher I Shaffrey; Frank Schwab; Christopher P Ames Journal: Neurosurgery Date: 2012-09 Impact factor: 4.654