Sagittal correction after short percutaneous fixation for thoracolumbar compression fractures: comparison of the combination of SpineJack® kyphoplasty and fractured vertebra screw fixation.

PURPOSE: The aim of this study was to compare two percutaneous pedicle fixations for the treatment of thoracolumbar fractures: one associating a jack kyphoplasty (SpineCut) and the other using intermediate screws (Trident). METHODS: All adult patients treated for single-level Magerl/AO type A thoracolumbar traumatic fractures in four orthopaedic departments, with SpineCut or Trident, with a one year minimum follow-up, were retrospectively included. Neurological disorders and osteoporotic fractures were not included. The following data were collected: age, sex, Magerl/AO type, type of surgery, and complications. Radiological parameters were analyzed on pre-operative CT scan, and on standing X-rays before discharge, at three months and one year post-operative: vertebral wedge angle (VWA), regional kyphosis angle (RKA), and traumatic regional angulation (TRA: difference between RKA and physiological values for each vertebra). RESULTS: Eighty patients were included, with 42 patients in SpineCut group and 38 in Trident group. Mean age was 41 ± 15.7 years. TRA correction did not differ between the groups: respectively 11.2 ± 8.1° in SpineCut versus 10.2 ± 9.1° in Trident group (p = 0.52). TRA loss of correction between early post-operative and three months was statistically higher in Trident group: -4 ± 5.1° versus -1.5 ± 3.8° (p = 0.03). After 3 months, TRA correction loss was comparable between the groups. Multivariate analysis demonstrated that pre-operative VWA was the only factor significantly associated with early TRA correction loss (p = 0.01). VWA correction and loss of correction did not differ significantly between the groups. No complications were observed. CONCLUSION: Percutaneous pedicle fixations of traumatic thoracolumbar fractures associating jack kyphoplasty and intermediate screws are both safe and efficient techniques.

Implant removal after short percutaneous pedicle fixation associated with SpineJack® kyphoplasty: is correction sustained?

PURPOSE: This study objective was to evaluate sagittal correction loss after instrumentation removal in patients treated for thoracic or lumbar compression fractures treated with SpineJack® kyphoplasty associated with short percutaneous pedicle screw fixation. METHODS: This retrospective multicenter study was carried out in three major French trauma centers. All patients with a single type A thoracic or lumbar fracture, treated by the studied technique between 2017 and 2020, have been included. Demographic data, fracture type, removal procedure achievement and term were collected. Radiological parameters were measured at five timepoints: pre-operative, intra-operative, immediate post-operative, early post-operative (< 3 months) and at follow-up (1 year). Vertebral wedge angle (angle between the two endplates of the fractured vertebra) and traumatic regional angulation (TRA-calculated by subtracting regional kyphosis from the physiological reference values). RESULTS: 150 patients were included. Mean age was 48.6 ± 17.8 years. Average follow-up was 14.4 ± 3 months. 82 patients had secondary instrumentation removal. Mean time to removal was 6.4 ± 2.4 months. TRA correction loss between immediate post-operative and last follow-up was greater in removal group: 5.1 ± 5.6° versus 2.7 ± 4.7° (p = 0.01). Material was removed earlier in younger patients (p = 0.002). TRA correction loss was similar in the early and late removal groups (p = 0.83). Multivariate analysis identified only Magerl/AO A3 fractures as risk factor for loss of TRA correction (p = 0.007). CONCLUSION: Instrumentation removal was associated with good radiological outcomes with a non-significant loss of vertebral wedge angle and tolerable loss of traumatic regional angulation (+ 2.4° compared to the no-removal group), even if performed early.