Efficacy and safety of VEPTR instrumentation for progressive spine deformities in young children without rib fusions

Abstract

This retrospective study analyses 23 children treated with vertical expandable prosthetic titanium rib (VEPTR) for correction of non-congenital early onset spine deformities. After the index procedure (IP), the device was lengthened at 6-month intervals. The average (av) age at the time of IP was 6.5 years (1.11-10.5). The av follow-up time was 3.6 years (2-5.8). Diagnosis included 1 early onset idiopathic scoliosis, 11 neuromuscular, 2 post-thoracotomy scoliosis, 1 Sprengel deformity, 2 hyperkyphosis, 1 myopathy and 5 syndromic. Surgeries (187) included 23 IPs, av 6.5 (4-10) device expansions per patient (149) and 15 unplanned surgeries. 23 complications (0.13 per surgery) included 10 skin sloughs, 5 implant dislocations, 2 rod breakages and 6 infections. Coronal Cobb angle was av 68 degrees (11 degrees -111 degrees ), at follow-up av 54 degrees (0 degrees -105 degrees). Pelvic obliquity was av 33 degrees (13 degrees -60 degrees ), at follow-up av 16 degrees (0 degrees -42 degrees ). T1 tilt was av 29 degrees (5 degrees -84 degrees ), two remained unchanged, the remainder improved 10 degrees -68 degrees. Sagittal plane: All but two had stable profiles, two hyperkyphosis of 110 degrees /124 degrees improved to 56 degrees /86 degrees. Space available for lung ratio was less than 90% in ten before the IP, improved in nine and deteriorated in one. Originally designed for thoracic insufficiency syndromes related to rib and vertebral anomalies, VEPTR proved to be a valuable alternative to dual growing rods for non-congenital early onset spine deformities. The complication rate was lower, the control of the sagittal plane and the pelvic obliquity was as good, but the correction of the coronal plane deformity was less than growing rods. However, VEPTR's spine-sparing approach might provoke less spontaneous spinal fusion and ease the final correction at maturity.