gms | German Medical Science

Objective: Cervicobrachialgia is often misinterpreted as a symptom related to disk herniation, while actually the “pseudoradicular“ pain sensation has to be attributed to a “functional instability“ of the vertebrae.

Methods: This study compares conventional functional lateral X-ray of the cervical spine (reference) to sagittal functional-dynamic imaging under in- and reclining stress in an open MRI (0.23*T Magnetom-Open (Siemens) in a spinal phase-array coil. The functional sequence was a T2-GE-FLAH-2D (0.8/45/15°)-sequence.

24 patients with a mean age of 43 years (21 - 68y) and meeting the criteria of cervicobrachialgia, “pseudo“-radicular pain sensation and symptoms lasting for >3 months were included into the study. Seven diagnostic parameters were evaluated: 1^st vertebral sliding, 2^nd functional instability, 3^rd ventral/dorsal widening, 4^th height of disc space, 5^th spondylar & uncovertebral arthrosis, 6^th neuroforaminal width, 7^th disc herniation & spinal canal stenosis.

Results: In 7/8 patients functional MRI revealed cervical vertebral sliding (=Meyerding I-III°): 1x C3/4, 2x C4/5, 3x C5/6 + 1x C6/7. In 4/4 patients MRI also showed a functional instability in the sagittal plane, ranging from 2–5 mm. In 2/3 cases of ventral and 3/3 cases of dorsal widening MRI could prove the instability in the axial plane. In 11/12 (osteo-)chondrotically altered disk spaces MRI demonstrated reduced disk height (>2 mm).

While MRI revealed cortical sclerosis (T2+T1: SI<) in just 10/12 segments, only MRI visualized alterations of the subcortical spongiosa (Modic I–III°). In 168 examined cervical segments (24 pats.) conventional X-ray and MRI discovered 43 vs. 38 segments with degenerative sclerosis with corresponding findings in 36 small vertebral joints.

Functional MRI discovered 19 relative (diameter <4 mm) and 11 absolute (diameter <2 mm) neuroforaminal stenoses. In 9 and 7 cases of foraminal stenosis inclination and reclination respectively triggered an intraforaminal root compression. X-ray depicted 2 older, partially calcified disk herniations, while MRI showed 9 DHs and 11 protrusions, respectively.

Conclusions: Dynamic functional imaging in an open MRI-system (1) reliably demonstrates a functional instability of the cervical spine, (2) allows for precise delineation of the cervical nerve roots in the neuroforamina, especially under in- and reclining stress, and (3) reveals disk herniations as well as spinal canal stenosis induced by spondylar and uncovertebral arthrosis.