Prospective radiographic and clinical outcomes of dual-rod instrumented anterior spinal fusion in adolescent idiopathic scoliosis: Comparison with single-rod constructs

STUDY DESIGN. Anterior single or dual-rod instrumentation may be performed for the treatment of main thoracic, thoracolumbar, or lumbar adolescent idiopathic scoliosis (AIS) curves. OBJECTIVE. To compare the results of anterior dual-rod instrumentation in single-major AIS curves with our previous experience using single-rod constructs. SUMMARY OF BACKGROUND DATA. Several reports have described the use of anterior single-rod instrumentation for the treatment of AIS curves with acceptable correction rates but with pseudarthroses/implant failures of up to 31%. METHODS. A total of 60 consecutive patients with AIS (12 males and 48 females; average age 15.3 years) with major thoracic (n = 18) or thoracolumbar/lumbar (n = 42) curves were treated with dual-rod instrumented anterior spinal fusion. Follow-up was 2-5 years. Patients were evaluated prospectively with Scoliosis Research Society (SRS) questionnaires. RESULTS. Major thoracic curves were corrected from a mean of 55° to 27° (51% correction), while major thoracolumbar/lumbar curves were corrected from an average of 51° to 17° at latest follow-up (67% correction). No pseudarthroses were identified. With the use of single-rod constructs, a similar amount of coronal correction was obtained for both thoracic (47%) and thoracolumbar/lumbar curves (70%). However, the pseudarthrosis rate for single-rod constructs was 5.5%. The obvious trend toward a lower pseudarthrosis rate in dual-rod (0/60) versus single-rod (5/90) constructs was not statistically significant (P = 0.07). Follow-up SRS questionnaire data for patients with dual-rod instrumentation showed 95% satisfaction, and 93% would choose the same treatment with similar results in the single-rod instrumentation study, 88% patient satisfaction, and 89% choosing the same treatment. Overall SRS scores improved after treatment (P < 0.01). SRS domain scores improved at a significant level for pain (P = 0.05), self-image (P < 0.01), and function (P = 0.01). CONCLUSION. In this largest, to our knowledge, single-center report of dual-rod constructs for patients with AIS, a similar amount of radiographic deformity correction was obtained when compared to single-rod implants. However, the absence of any pseudarthroses in the 60 patients with dual-rod is a distinct advantage.