Deformed Complex Vertebral Osteotomy Technique for Management of Severe Congenital Spinal Angular Kyphotic Deformity.

OBJECTIVES:To (i) introduce the deformed complex vertebral osteotomy (DCVO) technique for the treatment of severe congenital angular spinal kyphosis; (ii) evaluate the sagittal correction efficacy of the DCVO technique; and (iii) discuss the advantages and limitations of the DCVO technique. METHODS:Multiple malformed vertebrae were considered a malformed complex, and large-range and angle wedge osteotomy was performed within the complex using the DCVO technique. Patients with local kyphosis greater than 80° who were treated with DCVO and did not have tumors, infections, or a history of surgery were included. A retrospective case study was performed in these patients with severe angular kyphosis who underwent the DCVO technique from 2008 to 2016. Demographic data, the operating time, and the volume of intraoperative blood loss were collected. Spinopelvic parameters (pelvic incidence [PI], pelvic tilt [PT], and sacral slope [SS]), local and global sagittal parameters (deformity angle, thoracic kyphosis [TK], and lumbar lordosis [LL]), visual analog scale (VAS) score, and Oswestry disability index (ODI) score were recorded pre- and postoperatively. Paired t-tests (α = 0.05) were used for all data (to compare the mean preoperative value with the mean postoperative and most recent follow-up values). P < 0.05 was considered statistically significant. RESULTS:Twenty-nine patients with a mean age of 34 years (range, 15-55) were included in the final analysis. Seventeen patients were male, and 12 were female. The mean follow-up was 44 months (range, 26-62). The mean operating time was 299 min (range, 260-320 min). The mean blood loss was 2110 mL (range, 1500-2900 mL). Three patients had T7 -T8 deformities (3/29, 10.3%), six had T8 -T9 deformities (6/29, 20.7%), six had T9 -T10 deformities (6/29, 20.7%), 10 had T10 -T11 deformities (10/29, 34.5%), three had T11 -T12 deformities (3/29, 10.3%), and one had T9 -T11 deformities (1/29, 3.4%). The mean local deformity angle significantly improved from 94.9° ± 10.8° to 24.0° ± 2.3° through the DCVO technique, with no significant loss at the follow-up. Moreover, the global sagittal parameters and spinopelvic parameters exhibited ideal magnitudes of improvement; TK decreased from 86.1° ± 12.1° to 28.7° ± 2.5°, LL improved from 94.5° ± 4.1° to 46.1° ± 3.0°, and PI minus LL improved from -60.9° ± 6.5° to -13.7° ± 2.6°. Both the VAS and ODI scores significantly improved at the last follow-up. CSF fistula and neural injury did not occur during the perioperative period. At the last follow-up, fixation failure was not observed. CONCLUSION:The DCVO technique provides an alternative and effective method for the treatment of congenital severe angular spinal kyphotic deformities and may decrease the occurrence of perioperative complications.