Posterior elements disruption with hybrid constructs in AIS patients: is there an impact on proximal junctional kyphosis?
OBJECTIVE
Proximal junctional kyphosis (PJK) is a frequent proximal adjacent segment disease following spinal fusion in adolescent idiopathic scoliosis (AIS) and its rate has been estimated to 28% in the literature. The etiology is multifactorial, and risk factors associated with PJK are controversial. The aim of this study was to demonstrate that the disruption of muscular and bony tissue above the upper instrumented vertebra (UIV) during surgery does not increase the rate of PJK in patients undergoing posterior fusion for adolescent idiopathic scoliosis.


METHODS
50 patients with AIS operated between June 2014 and January 2016 were included. Every patient underwent a long posterior spine arthrodesis with a hybrid construct (proximal lamino-laminar claw, thoracic sublaminar bands and lumbar screws). The dissection of posterior elements above the UIV was necessary for the placement of proximal anchors. Radiographic analysis including proximal junctional angle, spino-pelvic parameters (cervical lordosis, thoracic kyphosis TK, lumbar lordosis, pelvic incidence, pelvic tilt, sacral slope) and sagittal vertical axis were collected preoperatively and postoperatively at the last control. The numbers of fused levels, locations of upper instrumented vertebra, locations of lower instrumented vertebra, length of fusion segments were also recorded. Multiple odd ratios and other statistical analysis were performed to evaluate the relation between PJK and the potential risk factors.


RESULTS
There were 43 females and 7 males with a mean age of 14.8 years at surgery. PJK occurred in 5 out of 50 cases with an incidence of 10%. The mean follow-up was 18 months. There was no significant difference in gender (OR 1.36, p = 0.8), decrease of TK (OR 1.63, p = 0 0.69), location of UIV (OR 2.25, p = 0.4), LIV (OR 2, p = 0.55), and SVA change (OR 1.63, p = 0.46).


CONCLUSIONS
The disruption of ligamentous and bony tissue proximal to the UIV during the surgery does not increase the rate of PJK. Level of evidence IV.
Pediatric Orthopedics, Hopital de la Timobe, CHU Timone, Aix Marseille University, 264 rue Saint Pierre, 13005, Marseille, France.
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Ghailane
Pediatric Orthopedics, Hopital de la Timobe, CHU Timone, Aix Marseille University, 264 rue Saint Pierre, 13005, Marseille, France. sebastien.pesenti@ap-hm.fr.|Aix Marseille University, CNRS, ISM, Institute of Movement Science, Marseille, France. sebastien.pesenti@ap-hm.fr.
Sebastien
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Pesenti
Pediatric Orthopedics, Hopital de la Timobe, CHU Timone, Aix Marseille University, 264 rue Saint Pierre, 13005, Marseille, France.
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Peltier
Pediatric Orthopedics, Hopital de la Timobe, CHU Timone, Aix Marseille University, 264 rue Saint Pierre, 13005, Marseille, France.
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Choufani
Aix Marseille University, CNRS, ISM, Institute of Movement Science, Marseille, France.|Spine Unit, CHU Timone, Marseille, France.
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Blondel
Pediatric Orthopedics, Hopital de la Timobe, CHU Timone, Aix Marseille University, 264 rue Saint Pierre, 13005, Marseille, France.
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Jouve
D000293:Adolescent; D005260:Female; D005602:France; D006801:Humans; D015994:Incidence; D007738:Kyphosis / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology; D008297:Male; D009984:Orthopedic Fixation Devices; D011183:Postoperative Complications / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology; D011859:Radiography / Q000379:methods; D012189:Retrospective Studies; D012307:Risk Factors; D012600:Scoliosis / Q000175:diagnosis / Q000601:surgery; D013123:Spinal Fusion / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods; D013131:Spine / Q000000981:diagnostic imaging / Q000601:surgery; D016896:Treatment Outcome
Adolescent idiopathic scoliosis; Ligamentous disruption; Proximal junctional angle; Proximal junctional kyphosis; Risk factors