Figure 3.

A 52-year-old male single segmental CSM patient with low cervical instability. Magnetic resonance image showing obvious spinal cord compression and ISI of the spinal cord (Grade 1) at C5–6 (A); Lateral radiograph showing C4–C5 instability with 3.5 mm horizontal displacement in resting position (B) and 4.3 mm in extension position (C); Postoperative radiograph showing single-level anterior cervical decompression and fusion at C5–6, while the unstable segment (C4–5) was not processed (D).