Apical pedicle subtraction osteotomy in the treatment of severe rigid kyphoscoliosis:a preliminary report

Abstract

To evaluate the safety and efficacy of apical pedicle subtraction osteotomy (PSO) in the treatment of severe kyphoscoliosis. The radiographic films of the 12 severe kyphoscoliosis patients treated with apical pedicle subtraction osteotomy were retrospectively reviewed, and the Cobb angles of the scoliosis and kyphosis and coronal trunk balance were measured and analyzed. Medical records and operation charts were reviewed to record any peri-operative complications. Twelve patients were included in this study, 4 males and 8 females, with an average age of 20.1 years old. Of the 12 patients, 2 were adult kyphoscoliosis and 10 were congenital kyphoscoliosis. The mean follow-up time was 9.2 months. The mean fusion levels were 12 segments and the mean operation time was 5.0 hours. The mean estimated blood loss during operation was 1517 ml and the mean autotransfusion and allotransfusion were 780 ml and 1109 ml, respectively. The mean preoperative and postoperative coronal Cobb angle of the main curve was 100.9 degrees and 48.8 degrees , with an average correction rate of 51.8% (P = 0.000). The mean preoperative and postoperative sagittal Cobb angle of the kyphosis was 81.7 degrees and 42.2 degrees , with an average correction rate of 49.8% (P = 0.000). At final follow-up, the mean Cobb angles of the scoliosis and kyphosis were 50.7 degrees and 46.0 degrees , respectively, and no obvious correction loss was found (P = 0.763, P = 0.698). The mean coronal trunk balance before, after surgery and at final follow-up was 16.3 mm, 14.7 mm, and 12.0 mm, respectively. Only 1 patient had trunk shift greater than 20 mm at final follow-up. After operation, two patients suffered from transient numbness and weakness of the unilateral lower extremity with complete recovery in one week. No spinal cord injury occurred. Apical pedicle subtraction osteotomy can be easily performed in the treatment of severe rigid kyphoscoliosis with satisfactory correction results and few neurologic complications.