OBJECTIVE: To analyze the clinical characteristics of intervertebral disc tissue injury and herniation into the vertebral body in thoracolumbar fracture on fracture healing, vertebral bone defect volume and intervertebral space height. METHODS: From April 2016 to April 2020, a total of 140 patients with thoracolumbar single vertebral fracture combined with upper intervertebral disc injury treated with pedicle screw rod system reduction and internal fixation in our hospital. There were 83 males and 57 females, aged from 19 to 58 years old, with an average age of (39.33±10.26) years old. All patients were followed up regularly 6 months, 12 months and 18 months after surgery. The patients with injured intervertebral disc tissue not herniated into the fractured vertebral body were the control group, and the patients with injured intervertebral disc and herniated into the fractured vertebral body were the observation group. By detecting the thoracolumbar AP and lateral X-ray films, CT and MRI of the thoracolumbar segment at different follow-up time, calculate the changes of the wedge angle of the fractured vertebral body, the sagittal kyphosis angle and the height of the superior adjacent intervertebral space, the changes of the fracture healing and bone defect volume after the reduction of the vertebral body, and the changes of the intervertebral disc degeneration grade. The prognosis was evaluated by visual analogue scale(VAS) and Oswestry disability index(ODI). Finally, the differences of the above results among different groups were comprehensively analyzed. RESULTS: All the patients had normal wound healing without complications. A total of 87 patients received complete follow-up data, at least 18 months after internal fixation. Thoracolumbar AP and lateral X-ray films showed that 18 months after the reduction and internal fixation operation, the vertebral wedge angle, sagittal kyphosis angle and the height of the upper adjacent intervertebral space in the observation group were greater than those in the control group(P<0.05). CT scanning showed that the deformity of the fracture healed 12 months after the vertebral body reduction in the observation group and formed a "cavity" of bone defect connected with the intervertebral space, and its volume was significantly increased compared with that before (P<0.05). MRI scanning showed that the degeneration rate of injured intervertebral discs in the observation group was more serious than that in the control group 12 months after operation(P<0.05). However, there was no significant difference in VAS and ODI score at each time. CONCLUSION Herniation of injured intervertebral disc tissue hernias into the fractured vertebral body leads to increased bone resorption defect volume around the fracture and forms a malunion "cavity" connected with the intervertebral space. This may be the main reason for the change of vertebral wedge angle, the increase of sagittal kyphosis angle and the decrease of intervertebral space height after removal of internal fixation devices.
Male ; Female ; Humans ; Adult ; Middle Aged ; Young Adult ; Vertebral Body/injuries* ; Lumbar Vertebrae/injuries* ; Thoracic Vertebrae/injuries* ; Treatment Outcome ; Fractures, Bone ; Spinal Fractures/surgery* ; Fracture Fixation, Internal/methods* ; Pedicle Screws ; Kyphosis/surgery* ; Intervertebral Disc/surgery* ; Hernia ; Retrospective Studies

OBJECTIVETo explore the ideal screw entry point and optimal trajectory for anterior C1 lateral mass screw internal fixation, and provide an anatomical basis for the technique of anterior C1 lateral mass screw placement.

METHODSA radiographic analysis of the anatomy of the C1 lateral mass using Computed tomography, CT scan was performed in cervical spine of 56 healthy Chinese adults (28 males, 28 females; mean age, 36.5 years; age range, 18-55 years), by using the Mimics software to reconstruct the 3-D morphology of C1 lateral mass and measuring the inside, middle and outside effective height of the C1 lateral mass in front and back. Measuring the C1 lateral mass safe width with different extraversion angles range from 0° to 30° with a uniform interval of 5°, to find out the ideal extraversion angle. Measuring the range of sagittal angle, to find out the ideal sagittal angle.

RESULTSThe inside (H1), middle (H3) and outside (H5) effective height of the C1 lateral mass in front is 6.67 mm, 12.09 mm, and 17.51 mm, the inside (H2), middle (H4) and outside(H6) effective height of the C1 lateral mass in back is 8.17 mm, 13.20 mm, and 18.22 mm. When the extraversion angle choose 0°, 5°, 10°, 15°, 20°, 25°, 30°, and δ, the relative results of safe width (SW) of lateral mass were 4.73 mm, 5.36 mm, 5.90 mm, 6.33 mm, 6.44 mm, 5.70 mm, 4.38 mm, 6.95 mm averagely. The mean distance along the atlas anterior surface between the anterior tubercle and the screw entry point was 12.80 mm, the mean distance from the inferior border of the lateral mass to the screw entry point was 6.87 mm. The range of sagittal angle is 24.22° (-17.74°∼6.48°) .

CONCLUSIONSThe ideal extraversion angle was 21.14°. The mean distance along the atlas anterior surface between the anterior tubercle and the screw entry point was 12.80 mm. The mean distance from the inferior border of the lateral mass to the screw entry point was 6.87 mm. The ideal sagittal angle is -5.63°. These measurements may facilitate anterior C1 lateral mass screw fixation decreasing the risk of injury to the spinal cord, vertebral artery, and internal carotid artery theoretically. Delineating the individual anatomy in each case with CT scan before surgery is recommended.

Adolescent ; Adult ; Bone Screws ; Carotid Artery, Internal ; diagnostic imaging ; Cervical Atlas ; Cervical Vertebrae ; diagnostic imaging ; surgery ; Female ; Fracture Fixation, Internal ; instrumentation ; Humans ; Image Processing, Computer-Assisted ; Male ; Middle Aged ; Reconstructive Surgical Procedures ; Tomography, X-Ray Computed ; Vertebral Artery ; diagnostic imaging ; Young Adult

OBJECTIVETo investigate the relationship of upper cervical pedicle and vertebral artery (VA) location in order to improve the safety of transpedicular screw insertion.

METHODSThe vertebral arteries on 12 sides of 6 adult pate cadaverous specimens were dissected. The distance between VA and VA groove at the atlas needling point of transpedicle screw, and the distance between VA and the inner edge of axis cervical foramen, and the VA external diameter in axis cervical foramen were measured respectively.

RESULTSThe distance between VA and VA groove was (1.96 ± 0.72) mm on the left and (1.99 ± 0.61)mm on the right at the atlas needling point of transpedicle screw, the distance between VA and the inner edge of axis cervical foramen was (2.23 ± 0.43) mm on the left and (2.30 ± 0.39) mm on the right, the VA external diameter in axis cervical foramen was (3.03 ± 0.48) mm on the left and (2.98 ± 0.75) mm on the right.

CONCLUSIONIt is unlikely to injury VA when the transpedicle screws of upper cervical vertebrae were implanted correctly besides high straddled VA, and the individualization must be performed in the process.

Adult ; Aged ; Cervical Vertebrae ; surgery ; Female ; Fracture Fixation, Internal ; methods ; Humans ; Male ; Middle Aged ; Pedicle Screws ; Vertebral Artery ; anatomy & histology

Adult ; Cervical Atlas ; injuries ; Fracture Fixation, Internal ; Humans ; Male ; Spinal Fractures ; diagnostic imaging ; surgery ; Tomography, X-Ray Computed ; Vertebral Artery

Osteoporosis ; Vertebral Fracture ; Autonomic Dysreflexia ; Dysautonomia