Fig. 4.

A representative case of Period E. A 52-year-old man with failed C4–C6 anterior fusion for cervical spondylotic radiculopathy. a Anteroposterior X-ray film after surgery. b Postoperative CT at C6. Right and left APA of C4 were 50° and 52°, respectively. The corresponding STA were 40° and 28°, respectively. Left C4 screw was recognized as “complete perforation”. Although the patient showed neither neurological complications nor vertebral artery insufficiency, screw removal was not undertaken. After 8 years of surgery, he is doing well with some posterior neck pain and slight radicular pain in the left arm