The Surgical Treatment Principles of Atlantoaxial Instability Focusing on Rheumatoid Arthritis

Figure 1

Preop dynamic lateral radiographs revealed AAI ((a) and (b)). The atlantodental interval 6 mm in flexion position (b) is measured (double-headed arrow). Postop radiographs revealed atlantoaxial fusion with LC1-PC2 system ((c) and (d)).

(a)

(b)

(c)

(d)