Study design: Retrospective case series.
Objectives: To analyze the outcomes at skeletal maturity of patients treated with a single traditional growing rod (GR). To compare results of patients according to whether posterior spinal fusion (PSF) was performed at treatment completion.
Summary of background data: Few studies examined the end results of GRs at skeletal maturity. There is no agreement on requirement of PSF at GR treatment completion.
Methods: Clinical and radiological analysis of consecutive patients with severe and/or progressive scoliosis treated initially with traditional single GR. Group comparisons of patients with PSF and without fusion surgery at treatment completion.
Results: Thirty-four patients underwent traditional single GR implantation at a median age of 11.7 years. Median follow-up was 6.5 years. At last follow-up, T1-S1 distance was increased by a median 116 mm (P < 0.001) and median major curve Cobb angle was changed from 55° preoperatively to 30° (P < 0.001). Complications included 26 rod fractures, 1 implant prominence, 4 proximal junctional kyphosis, 2 proximal hook dislodgments, and 2 wound infections. At the beginning our experience, PSF was performed systematically in 17 patients. Relying on spinal ankylosis, 17 patients were subsequently not fused at GR treatment completion (single GR removed N = 2, single GR retained N = 7, dual GR surgery N = 8). There were no statistical differences between groups in improvements of radiological parameters from preoperative GR insertion to last follow-up. No GR fracture occurred after dual GR surgery.
Conclusion: Single GR allows curve control and promotes spinal growth. Dual GR is, however, recommended for rod fracture prevention and better correction maintenance. In patients with satisfactory deformity correction at skeletal maturity, one may consider retaining dual GR instead of performing PSF.
Level of evidence: 4.