BALLOON KYPHOPLASTY COMBINED WITH POSTERIOR SCREW-ROD SYSTEM IN TYPE A POST-TRAUMATIC VERTEBRAL FRACTURES: ARE BONE SUBSTITUTES REALLY USEFUL IN THIS ASSOCIATION?

Publication date: Available online 2 February 2019

Source: Injury

Author(s): Andrea Piazzolla, Giuseppe Solarino, Davide Bizzoca, Claudia Parato, Biagio Moretti

Abstract

Introduction

Recent studies have shown the efficacy and feasibility of the association between balloon kyphoplasty (BK) and minimally invasive posterior pedicle screw fixation, in post-traumatic type A vertebral fractures. None of them, however, has investigated the usefulness of PMMA or bone substitutes in this technique.

Materials and methods

55 patients (32 males, 23 females; mean age: 29.2), with post-traumatic thoracolumbar spine fractures, were treated with cementless BK combined with the posterior screw-rod system. Inclusion criteria: type A thoracolumbar vertebral fractures; absence of neurological deficit; one or more of these features (signs of vertebral instability; an anterior body wall compression >50° or a vertebral kyphosis (VK) >15°). Exclusion criteria: absence of a traumatic event; lumbar or hip T-score<-2.5; history of spinal infections; pre-existent disease that could compromise surgical procedure (i.e. previous vertebroplasty of the involved vertebrae); pregnancy; history of malignant neoplasm; BMI > 30; scoliosis>40°; metal allergies; any contraindication to CT.

At recruitment, the patients underwent a CT and a MRI of the spine to classify the fracture. Clinical evaluation was performed, using the Visual Analog Scale (VAS) and the Oswestry Disability Index (ODI), at baseline, 48 hours after surgery, at 3-months follow-up (fu), 6-months fu, 48 hours after the instrumentation removal and at 15-months fu. At each fu, VK, regional kyphosis (RK), central wall (MH/PH) and anterior wall (AH/PH) heights were assessed on lateral spine x-rays. At 6-months fu, a CT scan of the spine was performed to investigate the fracture healing. The posterior instrumentation was removed 7 months after surgery (range: 6-10 months).

Results

A significant reduction of mean VAS (p < 0.05) and ODI (p < 0.05) was observed after surgery; no impairment of these scores were observed after the instrumentation removal. A significant correction of VK, RK, AH/PH and MH/PH was recorded after surgery; no significant changes of these values were noticed at subsequent fu. After the instrumentation removal, only a RK impairment was recorded, but it was not significant.

Conclusions

PMMA or bone substitutes are not necessary, to keep the reduction of the endplate obtained with the balloon tamp, when BK is performed in the association with posterior percutaneous pedicle screws instrumentation.

http://bit.ly/2DPXHLi