H3S2 (3 hooks, 2 screws) construct: a simple growing rod technique for early onset scoliosis

Abstract

Purpose The purpose of this study was to review the preliminary results of an original fusionless method of treatment for progressive scoliosis in young children. Methods This study retrospectively reviewed the clinical records and radiographs of 23 children with progressive scoliosis who failed to respond to conservative treatment and underwent fusionless surgery using a single solid growing rod construct. All of them were ambulatory and had a followup of minimum 2 years. Sixteen patients were treated by consecutive distraction of a single intramuscular rod, and seven patients with rodding and anterior apical convex fusion. The etiology of the scoliosis included 11 idiopathic, 6 syndromic, 4 congenital, and 2 neurofibromatosis. At initial surgery, the average age was 9.3 ± 2.8 years, with a mean Cobb angle of 68°± 32°. Six patients underwent progressive scoliosis correction in a Stagnara cast prior to surgery, and one patient with an external halo-pelvic Ilizarov device. Results Fusionless single rodding allowed to maintain scoliosis correction in all patients. At an average of 3.5 ± 0.9 years after initial surgery, the 23 patients showed a correction of 57 % in the magnitude of the original curvature. Trunk height increase was documented in all patients and ranged from 1.5 to 11.9 cm. Rod failure was found in three patients and two patients had hardware infection. Only four cases of proximal junctional kyphosis were found at last follow-up. Conclusions Preliminary results from these series of patients show that the presented fusionless single growing rod technique allows to maintain correction of progressive early onset scoliosis while permitting spinal growth, with low complication rate. With this technique, lengthening procedures are used only once in every 10 months and patients are more comfortable as no brace is needed in most cases. This technique does not require any specific spine device. The procedure is simple and efficacious as long as some guidelines are respected.

The impact of posterior temporary internal distraction on stepwise corrective surgery for extremely severe and rigid scoliosis greater than 130°

“…Curve correction after use of initial posterior release (with six also having anterior release) and internal distraction, and before definitive fusion averaged 53 % (from 104°to 49°); correction was 6 % after the second distraction procedure; and the mean final curve correction was 80 % (from 104°to 20°). We should also note the correction of the scoliotic curve can be obtained progressively by iterative lengthening the growing rod to treat evolutive scoliosis in young children [57][58][59][60][61]. Miladi et al [57] showed the average improvement in Cobb angle after each rod-lengthening of the growing rod was 12.9, which includes two parts, the loss of correction due to spine growth between two rod lengthenings (10°) and the improvement of correction (2.9°).…”

“…We should also note the correction of the scoliotic curve can be obtained progressively by iterative lengthening the growing rod to treat evolutive scoliosis in young children [57][58][59][60][61]. Miladi et al [57] showed the average improvement in Cobb angle after each rod-lengthening of the growing rod was 12.9, which includes two parts, the loss of correction due to spine growth between two rod lengthenings (10°) and the improvement of correction (2.9°). Moreover, the main scoliotic curve was corrected from 68°± 32°(range 31°-142°) before surgery and preoperative reduction to 33°( range 11°-71°) after surgery, and 29°(range 15°-63°) on average at the last follow-up.…”

Fusionless surgery in early-onset scoliosis

“…The proximal fixation comprises 3 hooks (2 supralaminar and 1 pedicular) and distal fixation is provided by 2 pedicular screws, in what is known as H3S2 assembly [18,19]. The rod, in concave or in $ position, is curved according to the target spinal profile.…”

The MAGEC System for Spinal Lengthening in Children with Scoliosis: A NICE Medical Technology Guidance

“…The conventional rod arm of the case-matched study [ 19 ] included by the sponsor was also included within the evidence base, totalling 16 studies. Of the 16 conventional rod studies, 15 were retrospective case series and the remaining one was a prospective case series [ 28 ].

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