Comparison of Temporary Epiphysiodesis With RigidTacks™ and Blount‐Staples in a Porcine Animal Model Using Magnetic Resonance Imaging

Abstract

RigidTack™ is a newly developed implant for total temporary epiphyseodesis. The implant combines the technical advantages of the traditionally used rigid Blount-staples and the newer flexible eight-plates™. Thus, the implant is rigid like the Blountstaples, which may be a biomechanical advantage in temporary epiphyseodesis, and has an easy and guided implantation technique like the eight-plate™. As in eight-plates™, supposedly only two RigidTacks™ are sufficient for temporary epiphyseodesis compared to six Blountstaples in traditional treatment. The goal of this study was to compare Blount-staples and RigidTacks™ in regard to the total potential of growth arrest, the occurrence of postoperative implant-associated complications, secondary angular deformities, and central joint deformations. Twelve pigs were allocated in two groups (n = 6) for treatment of the proximal tibia. Total temporary epiphysiodesis was performed with either four Blount-staples or two RigidTacks™. Magnetic resonance imaging (MRI)-scans were performed before and 14 weeks after surgery, and the amount and distribution of growth arrest were evaluated by measuring the interphyseal distance in nine defined zones. Total temporary epiphysiodesis with two RigidTacks™ resulted in a similar amount of growth arrest as that of four Blount-staples. No significant coronal or sagittal angular deformities or joint deformities were observed in either group; however, one secondary loosening of a Blount-staple occurred. The study concluded that Blount-staples and RigidTacks™ are adequate implants for total temporary epiphysiodesis. Whether or not the precise implant-placement through the guided implantation technique of RigidTacks™ and a reduced number of implants indeed lead to a reduction of secondary angular deformities has to be investigated in further clinical trials.

Comparison of two types of fixation for proximal tibial epiphysiodesis: An experimental study in a rabbit model

“…Although three staples are used in the Blount's staple technique, some authors have advocated that two nails are sufficient with U nails made of stiff material. [23][24][25] Staple configuration changes compressive forces in different axes and this can affect coronal and sagittal plane angulation. We also consider that the distance between two K-wires is different than the width of the plate, making it more effective on the lateral angle alteration.…”

Growth arrest: leg length correction through temporary epiphysiodesis with a novel rigid staple (RigidTack)

“…Barbed and cannulated staple prongs were employed for secure sub-periosteal bone purchase and Kirschner (K)-wire guided insertion was used in order to ensure adequate and safe placement. 25 , 27 The surgeons, who were authors of this study, performed the procedures, and the duration of surgery (incision to suture) and fluoroscopy time were recorded.…”

“…Therefore, we have developed an implant for temporary ED with a reinforced crossbar and barbed, cannulated prongs for guided insertion to provide surgical simplicity, secure bone purchase, and improved clinical outcomes. Recently Hillebrand et al 25 have found a comparable efficacy between Blount staples and novel rigid staples in an animal model.…”

Epiphysiodesis for the treatment of tall stature and leg length discrepancy

“…Other implants designed for temporary ED (i.e., RigidTack TM ) ( Fig. 3e) are on the market and have already been tested in animal models, but clinical data on efficacy are still missing [48]. Residual LLD after growth arrest may be treated alternatively by lengthening procedures.…”