METHOD FOR PREOPERATIVE DETERMINATION OF THE DENSITY OF SPONGY BONE TISSUE OF THE VERTEBRAE BEFORE PERFORMING CIRCULAR FUSION IN CASES OF LESIONS OF THE LUMBAR SPINE Russian patent published in 2023 - IPC A61B6/00 

FIELD: medicine; traumatology; orthopedics; radiodiagnostics.

SUBSTANCE: invention can be used for preoperative determination of vertebral cancellous bone tissue density prior to circumferential fusion in case of lesions of the lumbar spine. In the preoperative period, spatial visualization of the structure of the cancellous bone tissue of the vertebral body of the affected segment of the lumbar spine of the patient is determined by the method of multispiral computed tomography by performing 64 slices per rotation of the gantry with a slice thickness of 0.625 mm, without gantry inclination with a voltage of 120 kV, a current of 175 mA, during the time 2.2 seconds at a pitch of 0.516:1 using a 150–220 mm overview scan. The construction of multiplanar reconstructions of the image of the affected segment of the lumbar spine in three mutually perpendicular planes — axial, frontal and sagittal is carried out. On the mid-axial section of the tomographically visualized vertebral body at the level of their venous plexus, the bone density of each lumbar vertebra from the affected segment of the lumbar spine subject to circular metal fixation using interbody fusion and stabilization with transpedicular screws is calculated in Hounsfield units. Then the calculated values of the density of each lumbar vertebra from the affected segment of the lumbar spine in Hounsfield units are compared with the previously studied density threshold values and the level of risk of solvency or failure of circular metal fixation is established. If the bone density of the L4 vertebra is more than 127 HU, the bone density of the L5 vertebra is more than 136 HU, and the bone density of the S1 vertebra is more than 142 HU, there is no risk of failure of circular metal fixation of the affected lumbar spine. At values of bone density of the vertebra L4≤127 HU, vertebral bone density L5≤136 HU and bone density of S1 vertebra≤142 HU establish a high risk of failure of circular metal fixation on the lumbar spine when planning to perform interbody fusion in combination with transpedicular fixation.

EFFECT: method provides prediction and planning of surgical treatment using circular fusion for lesions of the lumbar spine by determining the density of the vertebral body.

2 cl, 3 ex