一、影像学检查
1、For vertebral disintegration and mild slip, clinical diagnosis is difficult, X-ray examination is required, and the commonly used projection positions are anteroposterior view, lateral view and oblique view.
2、Anteroposterior view vertebral arch disintegration in anteroposterior view is often not easy to show, if there is a significant isthmus defect, when the plane of the fissure is parallel to the X-ray, a low-density oblique shadow can be seen under the annular shadow, if there is obvious slip, the lower margin of the slipped vertebral body and the lower vertebral body can be overlapped, showing a crescent-shaped density thickening, the5Lumbar transverse process overlaps with the anterior edge of the vertebral body.
3、Lateral view of both sides of the vertebral arch isthmus defect, a diagonal osseous density reduction shadow can be seen between the posterior and inferior articular processes of the vertebral arch root, the posterior part is higher than the anterior part, if the defect is unilateral, it is not easy to see.
4、If there is a slip, the vertebral body moves forward, but the degree is not equal, there are whole vertebral body complete forward movement, and there are also very slight forward movement, most of the slip in1/3To1/4Left and right, intervertebral disc degenerative change, vertebral space becomes narrow.
Two, measurement method of position measurement of slip
1、From the1Sacral plane anterior margin, draw a vertical line, this line should pass through the5Lumbar vertebral body anterior inferior margin, if the5Lumbar vertebral body forward slip, this line will pass through the vertebral body (Ullman line).
2、Suspected5Lumbar vertebral body forward slip, can be from the5Lumbar posterior superior and inferior margins, and the4Lumbar vertebral body posterior inferior margin to the1Sacral vertebral body posterior superior margin, if each line is connected to a straight line, then the two lines can intersect or be parallel, normally the angle of intersection of the two lines does not exceed2°, and in the4Lumbar vertebral body below the lower margin, if the two lines are parallel, the distance is not greater than3mm (Ullman line), with slip, the intersection point is at the4Lumbar vertebral body above the lower margin, according to the size of the angle of intersection of the two lines or the distance of the parallel lines, the slip can be divided into three degrees.
Three,Lumbar spondylolisthesis grading method
1、The degree of slip is the angle of intersection parallel distance mild3°~10°4~10mm moderate11°~20°10~20mm severe21°21mm above.
2、The1Sacral superior margin, divided into four equal parts, normally the5Lumbar vertebral body and the1Sacral vertebral body posterior margin, forming a continuous arc, with slip then the5Lumbar vertebral body anterior shift, anterior shift1/4is1°,2/4is2°,3/4is3°,Complete slip is4°。
3、Lateral film for diagnosis, the lateral film can distinguish true and false slips, the former increases the anterior and posterior diameter of the vertebral column; the latter does not change, and it can be seen that the intervertebral space becomes narrower, the adjacent vertebral body edge bone hardening, or lip-like hyperplasia and other degenerative changes.
4、Oblique film left and right45° The oblique view is the best position to show the isthmus. The normal appendage of the vertebral arch is like a hound, the dog's mouth represents the same side transverse process, the dog's eyes represent the pedicle, the dog's ears are the superior articular process, the dog's neck is the isthmus, the dog's body is the vertebral plate, the front and rear dog's legs represent the same side and the opposite side superior and inferior articular processes, the dog's tail is the opposite transverse process.
5、If the isthmus is not connected, a strip-like shadow with reduced density can be seen in the neck, resembling a hound wearing a collar, which is the bone non-union of the pedicle of the vertebral arch. If there is a slip, the superior articular process and transverse process follow the anterior movement of the vertebral body, like the neck of a decapitated dog.
6、CT, MRI: Deficit osseous part of pedicle, intervertebral disc protrusion, neural foramen, spinal canal deformation, pedicle fracture, asymmetrical spinous process biased to one side, CT may show 'double tube' sign.