BACKGROUND CONTEXT: The use of a novel lumbar pedicle cortical bone trajectory (CBT) screw has recently gained popularity, allowing for a minimally invasive approach and potentially improved screw purchase. However, to date, no studies have identified the ideal @entity1 population to utilize this technology. PURPOSE: This study reports the @entity79 ( @entity79 ) using Hounsfield units (HUs) along a CBT screw pathway. @entity1 with a greater difference in density of bone in the lumbar vertebrae between the fixation points of the CBT and traditional pedicle screw may be optimal candidates to realize the advantages of this technique. STUDY DESIGN/SETTING: A cross-sectional observational anatomic study was carried out. @entity1 SAMPLE: The sample comprised 180 randomly selected @entity1 with lumbar computed tomography imaging from L1 to L5 spinal levels. OUTCOME MEASURES: This study used computed tomography image-derived HUs as a metric for @entity79 . METHODS: A total of 180 @entity1 without previous lumbar surgery with computed tomography imaging of the lumbar spine met the inclusion criteria. @entity1 were chosen randomly from an institutional database based on age (evenly distributed by decade of life) and gender. Hounsfield units were measured at the expected end fixation point for both a cortical (superior/posterior portion of the vertebral body) and traditional pedicle trajectory (mid-vertebral body). RESULTS: Hounsfield unit values measured at the end fixation point for the CBT screw were significantly greater than that of the traditional pedicle screw in all age groups. The relative difference in HU values significantly increased with each decade of age (p<.001) and caudal lumbar level (p<.001). In the @entity3604 group, as determined by well-established HU values, there was a significantly greater difference in the @entity79 of the CBT fixation point compared with the traditional trajectory (p=.048-<.001). CONCLUSIONS: Bone mineral density as measured by HU values for the fixation point of the CBT screw is significantly greater than that of the traditional pedicle screw. This difference is even more pronounced when comparing @entity3604 and elderly @entity1 to the general population. The data in this study suggest that the potential advantages from the CBT screw such as screw purchase may increase linearly with age and in @entity3604 @entity1 .

Differences in XXXX of fixation points between lumbar cortical and traditional pedicle screws.

@entity1 :: ('9606', 'Species') :: ['Patients', 'patients', 'patient', 'PATIENT'] @entity79 :: ('MESH:D001847', 'Disease') :: ['bone mineral density', 'BMD'] @entity3604 :: ('MESH:D058866', 'Disease') :: ['osteoporotic']
@entity79 :: (MESH:D001847,Disease) :: ['bone mineral density']
