Table 1.

Clinical information of pediatric patients with atlantoaxial instability

Case no	Age at ope (yrs)	Diagnosis	Fusion construct	FU (mos)	Complications
1	10	Chronic AARF	C1–C2 transarticular screws	109	Fusion extension C2 to C3
2	13	Os odontoideum	C1–C3 transarticular screws	64	–
3	8	Chronic AARF	C1 lat mass + C2 PS	41	Perforation of the skull with a head pin placement
4	11	Klippel–Feil syndrome, basilar impression	O-C3 fusion (rod + sublaminar wiring)	68	Loss of reduction, reoperation
5	12	AAS	C1 lat mass + C2 PS	20	–
6	4	AAS, Down syndrome	C1 lat mass + C2 PS	20	C1 posterior arch fracture with lateral mass screw insertion Loss of reduction, reoperation
7	5	Os odontoideum, congenital kyphosis	O-C7 fusion (rod + PS)	16	Pedicle fracture with pedicle screw insertion fusion extension C7 to Th1
8	8	Chronic AARF	C1 lat mass + C2 PS	12	–
9	10	Os odontoideum	O-C3 fusion (rod + sublaminar wiring)	90	–
10	7	AAS, Down syndrome	O-C3 fusion (rod + sublaminar wiring)	93	Loss of reduction
11	6	Chronic AARF	O-C3 fusion (rod + sublaminar wiring)	95	Fusion extension C3 to C4

Ope operation, yrs years, FU follow-up, mos months, AARF atlantoaxial rotatory fixation, AAS atlantoaxial subluxation, lat mass lateral mass screw, PS pedicle screw