BL 11   Found at the level of the posterior border of the spine of the first thoracic vertebra and about 13mm lateral to the mid line. Insertion is perpendicular and 2.5cm deep depending on the size of the patient.
As with most of the Bladder points along the backline, the point is located by
(a) determining the position of the dorsal spine of a particular vertebra
(b) understanding that the tip of the dorsal spine is not a small point, but a variable sized structure, and that you need to determine the most posterior aspect of that structure by careful palpation
(c) understanding that the quoted lateral distance from the mid-line is only a general guide for the average dog, and that in each individual case you need to make an allowance for the width of the vertebrae of the individual.

In practice, these points are located just lateral enough so that the needle can slide down past the body of the vertebra in that region. Obviously a degree of interpretation and visualisation is required.
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In the case of BL11, you need to identify the spine of the first thoracic vertebra. You need to distinguish it from all the other thoracic vertebrae and ensure that you do not confuse it with the 7th cervical vertebra.
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Notice here the different sizes of the dorsal spines of C2, C7 and T1.
Notice also that
BL11 is located relative to the posterior aspect of the spine of T1.
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The easiest way to find T1 spine is to search in the area of the midline just anterior to the scapulae. In fat or muscular dogs this will be difficult and you may well have to make a judgement based on the thoracic vertebrae that you can feel. In a greyhound you need to push the head down as far as you can, and then palpate deeply in the midline with a posterior movement of the index finger. T1 will be the first spine that you encounter. Hold that spot with your finger as you release the head and it assumes its normal position, because quite often the contact with the spine of T1 will be lost as the head rises.

NOTE:- it is almost impossible to palpate the spine of C7.
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