Modified mini-open SRS-Schwab grade 4 osteotomy combined with percutaneous pedicle screws fixation in post-traumatic thoracolumbar kyphosis

Abstract

Background: We aimed to analyze the clinical results of Schwab grade 4 osteotomy combined with percutaneous pedicle screws (PPS) fixation for treatment of post-traumatic thoracolumbar kyphosis (PTK). Methods: Thirty four patients with PTK (group A) were included in our study. The average age was 54.9 ± 3.3 years. All patients had severe back pain with 8.6 ± 1.3 VAS scores. The affected level was T12 in 16 patients and L1 in 18 patients. The average preoperative regional kyphosis angle (RKA) was 30.7 ± 6.00. Three patients had neurological dysfunction with Asia grade D. All patients underwent Schwab grade 4 osteotomy combined with PPS fixation. The control group (Group B) were 26 PTK patients treated with Schwab grade 4 osteotomy and open pedicle screws fixation in our institution. Results: Operation time in groups A and B was 280 ± 50 min and 210 ± 30 min, respectively (P < 0.05). Estimated blood loss in groups A and B was 310 ± 70 ml and 630 ± 40 ml, respectively (P < 0.05). No cerebral spinal fluid leakage, segmental nerve function damage, and other complications observed during and after the operations in both groups. RKA, SVA, and LL improved significantly after surgery in both groups (P < 0.05). The average correction rate in groups A and B was 64.5 and 66.3% (P > 0.05). CT showed that the misplacement rate in groups A and B was 5.5 and 6.6% (P > 0.05). The average follow-up in groups A and B was 25.2 ± 7.6 months and 30.6 ± 2.7 months. No fracture and other complications were observed in both groups. Solid bone fusion was showed in all cases at 6 months follow-up. In groups A and B, all patients with preoperative neurological dysfunction recovered to Asia grade E at the last follow-up. The VAS score of back pain improved significantly from 8.6 ± 1.3 to 1.6 ± 1.0 at the last follow-up in group A (P < 0.05), while it improved significantly from 8.3 ± 1.2 to 3.0 ± 1.1 at the last follow-up in group B (P < 0.05). VAS of back pain was better in group A than that in group B. Conclusion: Schwab grade 4 osteotomy combined with percutaneous pedicle screws fixation is a minimally invasive, safe and effective method for PTK treatment.