Graduation Protocol After Growing-Rod Treatment: Removal of Implants without New Instrumentation Is Not a Realistic...

The growing rod remains an effective option in the treatment of early-onset scoliosis, and has previously been likened to an internal brace. While details of growing-rod treatment have been largely agreed on, the appropriate end point remains a matter of controversy. A decision was made in 2004, at the beginning of growing-rod treatment at our institution, to remove longitudinal instrumentation when the period of lengthening concluded and, similar to discontinuing a brace, leave the spine free.

From 2004, patients managed with a growing rod who were ≤10 years old at the time of the index surgery and had no previous surgery were enrolled in the prospective treatment pathway. For this report, the inclusion criteria were complete records and radiographs; regular lengthenings; no complications defined as SV (severity grade) IIA, IIB, III, or IV; and a minimum follow-up of 2 years after reaching the age of 14 years. At the age of 14 years, the patients were reevaluated and 1 of 3 treatments was undertaken. In Group 1, which included patients with adequate correction and no requirement for extension of fusion, the growing rods were removed. In Group 2, which included patients with inadequate correction and/or interval changes, the growing rods were removed and instrumented fusion was performed. In Group 3, which included patients with a Risser sign of 0 or who were otherwise immature, lengthening was continued.

Twenty-six patients met the inclusion criteria. The mean age at the time of the index operation was 82.6 months. There were 10 patients in Group 1, 9 patients in Group 2, and 7 patients in Group 3. Of the 10 patients whose rods were removed without additional instrumentation, 9 had clinically important worsening of the deformity and required reimplantation with fusion.

Despite the initial intention to remove the implants, allow the spine to regain motion, and observe patients when they turned 14, the results of this report reveal that only 10 of the initially included 26 patients met the criteria to do so. In 9 of these patients, the deformity worsened after removal, confirming that prolonged growing-rod treatment does not necessarily result in spontaneous, reliable fusion. Removal of spinal implants without new instrumentation is not a realistic graduation protocol following growing-rod treatment, and implants should be retained, or if extension is required, another procedure should be undertaken.

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.