A Comparison of SHILLA GROWTH GUIDANCE SYSTEM and Growing Rods in the Treatment of Spinal Deformity in Children Less Than 10 Years of Age

Background: The purpose of this study was to compare the outcomes of the SHILLA GROWTH GUIDANCE SYSTEM and "intermittent distraction growing rod" (IDGR) in the treatment of children (less than 10 y of age) with progressive spinal deformity. This was a multicenter retrospective study of the SHILLA used as an alternative treatment to IDGR to support an HDE submission for Food and Drug Administration approval. Methods: Inclusion criteria were progressive scoliosis in a patient less than 10 years of age at index procedure. The study population consisted of 19 SHILLA and 6 IDGR patients whose mean age was 6.1 and 5.8 years, respectively. Group demographics were similar between the 2 groups. Results: The initial major curve magnitude was 70.3 degrees for SHILLA and 68.3 degrees for IDGR, which decreased postoperatively to 22.4 degrees (68.1% improvement) and 32.2 degrees (52.9% improvement). During the first 4 years the correction for SHILLA varied from 40.5% to 53.4% and for IDGR from 40.9% to 56.9%. At last follow-up, T1-S1 length was 32.9 cm for SHILLA (4.2 increase from preoperation) and 34.0 cm (5.0 cm increase from preoperation) for IDGR. Average growth per month from T1-S1: SHILLA 0.14 cm, IDGR 0.11 cm. Sagittal T2-T12 preoperatively was 36.3 degrees for SHILLA and 30.0 degrees for IDGR. There were 29 reoperations in 12 of the 19 SHILLA patients (63.2%) and 40 reoperations in all 6 of the IDGR patients (100%) related to the index procedure. Conclusions: The SHILLA GROWTH GUIDANCE SYSTEM compares favorably with traditional IDGR constructs in terms of correction of the major curve, spinal length and growth, and maintenance of sagittal alignment. The >4-fold decrease in additional surgeries makes the SHILLA an attractive alternative to minimize comorbidities associated with additional surgeries. Levels of Evidence: Level III.