HOW TO INJECT THE CRANIAL SACRO-ILIAC
JOINT AREA OF THE HORSE USING
ULTRASOUND GUIDANCE
Ann Carstens
BVSc, MS, MMedVet(LA Chir), DTO, MMedVet(Diag Im), Dipl ECVDI, PhD
Clinical conditions of the pelvis of the horse are usually as result of traumatic
or degenerative conditions and often result in poor performance. Before the
advent of diagnostic ultrasonography, examination of the pelvis of the horse
was limited to clinical evaluation, radiography and scintigraphy and the
administration of local anaesthesia in specific areas. Optimal radiographic
images of the pelvis are still often only obtained in smaller horses and foals,
due to the width and density of the tissues present in average size adult
horses.
Ultrasonography has made the evaluation of soft tissue structures as well as
the near field bone cortices of the pelvis possible and particularly allowed the
visualization of the areas and sites of needle placement for injection of local
anaesthetics and medication of the area in the vicinity of the sacro-iliac (SI)
joint possible.
For the visualization of the cranial approach to the peri-articular area of the SI
joint, a curvilinear 2-4 MHz transducer is required. For injection, the area must
be sterily prepared, gloves used and a sterile technique adhered to with the
transducer placed in a sterile glove (or other sterile structure). Acoustic
coupling gel must be placed within the glove to ensure a good coupling
between the glove and transducer. Liberal use of alcohol on the area where
the needle will be placed is important both for visualization of the SI area and
the needle as it is advanced to the site of injection, as well as for maintenance
of sterility.
The cranial approach to injection of the SI joint area:
The area around the sacro-iliac joint can be injected by means of a cranial,
craniomedial, medial and two caudal approaches, but since the caudal
approaches have been reported to result in complications, the cranial and
craniomedial approaches are more advisable to perform.
Cranial approach: The transducer is held in a craniocaudal plane
(parasagitally) and moved along the cranial rim of the ilial wing until the
lateral aspect of the transverse process of L5 and the ileal wing is seen in one
image (approximately 5-8cm lateral to the lumbar dorsal spinous process. The
needle is inserted approximately 5-8 cm cranial to the probe and is directed
caudoventrally under the ileal wing until the tip touches bone or until the hub is
against the skin.
15-‐18
February
2016
East
London
Convention
Centre,
East
London,
South
Africa
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