Objective To observe the routes of acupuncture needle-insertion of the "nape four acupoints"(BL 10

GB20

GB 12

SJ 16)in the human cadavers and to explore the possible trigger-point location of cervical headache

so as to provide anatomic evidence for their clinical application.Methods Five human cadavers(male 3

female 2)were used in the present study.The needle inserting routes of the four acupoints Tianzhu(BL 10)

Fengchi(GB 20)

Wangu(GB 12)and Tianyou(SJ 16)at the nape were labeled with gentian violet first.The occipital tuberosity was taken as the original point

the horizontal projection of superior nuchal line as the abscissa

and the posterior median line as the ordinate

then

a two-dimension rectangular coordinate system was established to measure the horizontal projection of the"nape four points"and to estimate the trigger-point location

followed by making an analysis on their spatial relationship

and determining the reasonable routes of needle-insertion of the4 acupoints.Results For the"nape four points"

six needling-inserting routes or spots could be taken:(1)Tianzhu(BL 10)Ⅰ(perpendicular insertion)

i.e.

about 0.5 cunlateral to the posterior midline in parallel to BL 10;(2)Tianzhu(BL 10)Ⅱ(perpendicular insertion)

about 0.6cun lateral to the posterior midline at the skull base level;(3)Tianzhu(BL10)Ⅲ(perpendicular insertion)

about 0.6 cun below the BL 10 and about 1.3 cunlateral to the posterior midline

or the right inferior of BL 10 for oblique insertion;(4)Fengchi(GB 20)Ⅰ(oblique insertion along the skull base toward the lower part of the nose-tip)

about 2.25 cunlateral to the posterior midline at the depression site of the junction of the sternocleidomastoid and trapezius muscles on the upper portion in parallel to the skull base level and 2.25 cunlateral to the posterior midline;(5)Wangu(GB 12)Ⅰ(perpendicular insertion along the bone surface)

about 0.7 cun above the GB 12

i.e.

the inferior of the junction of the mastoid posterior root and the skull base;(6)Tianyou(SJ 16)Ⅰ

about 0.7 cun below the SJ 16

i.e.

the posterior margin of the sternocleidomastoid muscle

being the same to SJ 16 in the operation.Conclusion According to anatomical analysis

it is recommended to insert the acupuncture needles into the nape four acupoints along the Tianzhu(BL 10)Ⅰ

Ⅱ

Ⅲ

Fengchi(GB 20)Ⅰ

Wangu(GB 12)Ⅰ and Tianyou(SJ 16)Ⅰroutes mentioned above for achieving a better therapeutic effect.Cervical headache may have a close relation with the trigger-points at the occipital nape.