BL 54 has 2 alternate locations listed.

(1) is described as in the middle of the bulk of the gluteal muscle. Insertion is up to 25 mm depending on the size of the dog, or deep enough to anchor it for 20 minutes.

(2) (preferred) is described as lateral to the midpoint of the sacro-coccygeal space, and immediately above the neck of the femur. Insertion is about 1-2cm perpendicularly, using a 13mm or 25mm needle depending on the size of the dog to anchor the needle in the capsule of the hip joint.
 

Note the sacrococcygeal space between the spines of S3 & Coccygeal 1

In older texts you may come up with an erroneous location for BL54 at the centre of the posterior aspect knee crease, which has now been accepted as BL40.
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One way to find BL54 is to

(1) grasp the tail close to its root and raise and lower it with a "pump handle" type action, while palpating just anterior to the tail root. The sacrococcygeal space should become evident.
(2)To confirm, identify the spine of S3 and move your finger slightly posteriorly while "pumping" the tail....your finger should "fall into" the sacro-coccygeal space.
(3) Move laterally, (some authors say 3 Tsun, but that is a human location which does not apply to the quadriped) from the sacro-coccygeal space to the middle of the neck of the femur. This is
BL54.
BL54 is also described as located above the centre of the neck of the femur. To find it another way, you grasp the knee joint in one hand and move the knee in such a way as to rotate the hip joint in its socket. This will enable you to identify the greater trochanter of the femur. Then while still moving the knee backwards and forwards you can identify the neck of the femur. BL54 is directly above the centre of the neck, while GB29 is located just in front of the neck and GB30 is just behind the neck.
Together, BL54, GB29 and GB30 are the three most commonly used local points for the hip.
Note that there is an alternative location for BL54, in the centre of the bulk of the gluteal muscle.


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