Efficacy of satellite rod revision surgery via a combined anterior and posterior approach for rod fracture after posterior vertebral column resection in patients with severe thoracolumbar kyphosis / 中华创伤杂志

ABSTRACT

Objective:To investigate the clinical efficacy of satellite rod revision surgery via a combined anterior and posterior approach for rod fracture after posterior vertebral column resection (PVCR) in patients with severe thoracolumbar kyphosis.Methods:A retrospective case series study was conducted on the clinical data of 11 patients with rod fracture after PVCR for severe thoracolumbar kyphosis, who were treated in Henan Provincial People′s Hospital from January 2013 to January 2021. There were 6 males and 5 females, with the age range of 21-62 years [(35.4±13.0)years]. Among them, 4 patients had traumatic kyphosis, 4 presented congenital kyphosis and 3 showed tuberculous kyphosis. All the patients had obvious low back pain. According to the American Spinal Injury Association (ASIA) score, 2 patients were found with grade C, 2 with grade D and 7 with grade E. All the patients underwent revision surgery for internal fixation using satellite rod via a combined anterior and posterior approach. The operation time, intraoperative blood loss and postoperative hospital stay were recorded. The imaging parameters such as kyphosis Cobb angle, scoliosis Cobb angle, distance between C 7 plumb line and central sacral vertical line (C 7-CSVL), and distance between C 7 plumb line and sagittal vertical axis (SVA) were measured preoperatively, at 1 week postoperatively and at latest follow-up. At the same time, the visual analogue scale (VAS), Oswestry dysfunction index (ODI), and simplified Chinese version of the scoliosis research society-22 (SRS-22) questionnaire were used to evaluate the clinical efficacy. At the latest follow-up, the osteotomy fusion was evaluated by Suk criterion and ASIA score was used to evaluate the recovery of neurological function. The complications were also recorded for the patients. Results:All the patients were followed up for 24-84 months [(47.5±16.2)months]. The operation time was 100-220 minutes [(149.4±37.6)minutes], with the intraoperative blood loss of 150-350 ml [(246.3±64.6)ml] and the postoperative hospital stay of 5-8 days [(6.1±1.1)days]. The kyphosis Cobb angles [(18.5±3.2)° and (19.3±2.9)°] and the scoliosis Cobb angles [(11.8±2.2)°, (11.1±2.2)°] at 1 week post-operation and at the latest follow-up were all improved significantly compared with the preoperative ones [(60.4±6.3)°, (21.7±5.5)°] (all P<0.01), with the average correction rates being 69.4% and 45.6%, respectively, with no significant differences between 1 week post-operation and latest follow-up (all P>0.05). The C 7-CSVL was reduced from preoperative (21.2±4.3)mm to (15.7±2.4)mm at 1 week post-operation, and to (15.9±2.2)mm at the latest follow-up (all P<0.01). The SVA was improved from preoperative (51.0±6.8)mm to (16.6±3.6)mm at 1 week post-operation, and to (15.3±3.9)mm at the latest follow-up (all P<0.01). There were no significant differences in C 7-CSVL or SVA at 1 week post-operation or at the latest follow-up (all P>0.05). The VAS [(2.5±0.9)points, (1.9±0.9)points], ODI (20.1±5.4, 18.4±5.2) and SRS-22 [(83.4±5.8)points, (85.0±4.1)points] at 1 week post-operation and at the latest follow-up were significantly improved compared with the preoperative ones [(6.0±1.4)points, 57.2±8.7, (62.0±9.1)points] (all P<0.01), but no significant differences were found between 1 week post-operation and latest follow-up (all P>0.05). At the latest follow-up, the bone grafts achieved osseous fusion in all the patients, and the ASIA grade was improved from grade C to grade D in 2 patients and from grade D to grade E in 2 patients. No complications such as serious neurological or vascular injury occurred during perioperative period. No pseudoarthrosis formation, internal fixation loosening or fracture occurred during follow-up. Conclusion:Satellite rod revision surgery via a combined anterior and posterior approach for rod fracture after PVCR in patients with severe thoracolumbar kyphosis has the advantages of less trauma and faster convalescence, excellent results of deformity correction, significant pain relief, functional improvement, and fewer complications.