TABLE I.

Frequency Distribution of TLTV and LSTV

	No. of Patients	TLTV* (N = 96)				Non-TLTV*(N = 28)
		No. of Presacral Vertebrae†				No. of Presacral Vertebrae‡
		23	24		25	24	25
		T12 and L4	T12 and L5	T13 and L4	T13 and L5	T12 and L5	T12 and L6	T13 and L5
LSTV	111	7	21	23	36	17	6	1
Castellvi type II	28	0	10	1	10	5	1	1
Castellvi type III	42	0	9	1	26	3	3	0
Castellvi type IV	4	0	2	0	0	0	2	0
S6	37	7	0	21	0	9	0	0
Non-LSTV	13	0	1	1	7	0	3	1
Total§	124	7	22	24	43	17	9	2

^*The values are given as the number of patients.

^†The number of vertebrae is counted from C2; there are 87 patients in the LSTV group and 9 patients in the non-LSTV group.

^‡The number of vertebrae is counted from C2; there are 24 patients in the LSTV group and 4 patients in the non-LSTV group.

^§The numbers represent the sum of LSTVs and non-LSTVs.