Safety of Traditional Growing Rods in Patients with Early-Onset Congenital Scoliosis Associated with Type-I Split Cord Malformation

Abstract

Background: Literature regarding the application of traditional growing rod (TGR) instrumentation in patients with early-onset congenital scoliosis with type-I split cord malformation is scarce. The purpose of the present study was to assess the safety and effectiveness of TGR surgery and repeated lengthening procedures in patients with congenital scoliosis with type-I split cord malformation not treated with prophylactic osseous spur excision. Methods: Thirteen patients with early-onset congenital scoliosis associated with type-I split cord malformation and a stable neurologic status between March 2009 and July 2020 were recruited. All patients underwent primary TGR surgery and subsequent repeated lengthening procedures without osseous spur excision by the same surgical team. Clinical information and radiographic data from the preoperative, postoperative, and latest follow-up periods were collected. Results: The mean preoperative Cobb angle of the major coronal curve was 74.62° ± 25.59°, the mean early postoperative angle was 40.23° ± 17.89°, and the mean latest follow-up angle was 40.62° ± 16.60°. The scoliotic deformity correction percentage was 46.81% ± 12.26% after the initial operation and 45.08% ± 15.53% at the latest follow-up. Compared with the preoperative values, significant improvements were observed in the coronal and sagittal balance early postoperatively and at the latest follow-up (p < 0.05 for all). The average annual amounts of spinal height gained were 15.73 ± 5.95 mm at T1-S1, 8.94 ± 3.94 mm at T1-T12, and 12.02 ± 6.70 mm between the instrumented segments. The total height gained at T1-S1 and T1-T12 was 72.18 ± 28.74 mm and 37.62 ± 12.53 mm, respectively. No intraoperative neurophysiological monitoring events were observed, and no case of neurological deficit was observed postoperatively or during follow-up. Conclusions: Patients without neurologic deficit and having a stable neurologic exam who have early-onset congenital scoliosis associated with type-I split cord malformation can safely and effectively undergo TGR surgery, followed by repeated lengthening procedures, without prophylactic osseous spur excision. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.