Fig. 5. These composite images depict three different grades of alterations in echogenicity and homogenicity in the lumbosacral disc. Median plane images are displayed along the top and transverse images along the bottom. A1 and A2, Mild change in echogenicity and homogenicity; B1 and B2, moderate; C1 and C2, severe.
ventral sacroiliac ligament long axis is oblique to the paramedian imaging plane and perpendicular to the joint margin; therefore, probe manipulation is re- quired to optimize images of this ligament. Make longitudinal images of the caudomedial margin of the sacroiliac joint including the ventral sacroiliac ligament (Fig. 4).
Optional: Step 7: Psoas Minor Tendon
Move the entire probe in a lateral and ventral direc- tion along the ventral concavity of the ilium. The psoas minor tendon is encountered and can be identified by the typical imaging characteristics of a tendon (long, parallel hyperechoic fibers). This
structure can be tracked by means of ultrasound to its attachment on the ilium.
Step 8
Repeat for the contralateral side. Using the same imaging landmarks identify the contralateral in- tervertebral forminae, lumbosacral intertransverse joint, sacroiliac joint, and ventral sacroiliac liga- ment. The psoas minor tendon and its insertion on the ilium can also be visualized at this site. Ultrasound images were reviewed on a dedicated workstation with DICOM viewing software (eFilm, Merge Healthcare), including digital calipers. One author reviewed the images of the lumbosacral disc,
