JVD 2020 #2 Standing Arthroscopic Treatment of Temporomandibular Joint Sepsis in a Horse; Elzer

Question 1

Describe the equine TMJ

Answer 1

Diarthrodial articulation between the condylar process of the mandible and zygomatic process of the squamous temporal bone.
A well-developed fibrocartilageous disc separates the joint into dorsal & ventral compartments that normally do not communicate.
The caudolateral & rostrolateral synovial pouches of the dorsal compartment provide access for arthrocentesis/scopy

Question 2

What are the clinically relevant anatomic structures in close proximity to the equine TMJ?

Answer 2

parotid gland
transverse facial artery, vein & facial nerve
maxillary artery & vein
temporohyoid joint
lateral aspect of the gutteral pouch
external acoustic meatus
tympanic part of temporal bone
and petrotympanic fissure linking the TMJ and middle ear

Question 3

What concurrent conditions were present for the horse with right TMJ sepsis?

Answer 3

otitis media
temporohyoid osteoarthropathy (THO)
(suspect due to close anatomic proximity)

Question 4

DV radiograph showing thickening of the R stylohyoid bone (white arrow) and temporohyoid articulation (arrow head)

Answer 4

DV radiograph showing thickening of the R stylohyoid bone (white arrow) and temporohyoid articulation (arrow head)