Arthrocentesis Flashcards
Why would you do an arthrocentesis ?
Lameness evaluation
Clinopathological evaluation
Contrast studies
Wound involvement
Joint communications
Theraputic — medication or lavage
Routinely treated synovial structures of the forelimb?
Distal interphalangeal (DIP) Metacarpal phalangeal (MCP) DFTS Carpal joints
Routinely treated synovial structures of the hindlimb?
Metatarsal phalangeal (MTP)
DFTS
TMT/DIT
Stifle
T/F: you should always clip for the area for IA injections
False
Site is sterile clipped or non clipped
Clipping can actually increase little hair debris
What needle size is used for most IA injections?
20g 1”
Larger gauge needles increases risk of contamination
How can you minimize joint contamination ?
Use needles ONCE
Limit use of spinal needles or remove hair prior to use of spinal needles
Removal of hair might be contraindicated with hypodermic needles
> 18G needles increase risk of hair contamination
Allow fluid to drip out of hub or aspirate prior to injection to clear tissue and hair debris
IA antibiotics
500mg of __________ provides 72hrs concentration >MIC for most common pathogens
Amikacin
What IA antibiotic are we administering to our donkeys and how much?
Ceftiofur (50mg/ml)
Giving 2mls (100mg)
What are the landmarks for radiocarpal arthrocentesis ?
Palate distal medial ridge of the radius and proximal edge of the radiocarpal bone
Insert needle midway between these, and between the ECR and CDE tendons
What are the landmarks for an intercarpal arthrocentesis ?
Between distal ridge of radiocarpal bone and proximal edge of 3rd carpal bone
What synovial structures communicate at the carpus?
Inter-carpal joint and carpometacarpal joint (CMC)
What are the landmarks for tibiotarsal joint arthrocentesis ?
Palate medial malleolus of tibial
Insert needle medial or lateral to saphenous vein as it crosses the tarsus (1-1.5” distal to medial malleolus in horses)
Landmarks for the tarsometatarsal joint?
Insert needle just proximal to the head of the 4th metatarsal (lateral splint) dorsomedially and at a slightly distal angle
What needle size do you use for arthrocentesis of distal interphalangeal (coffin) joint?
20g 1 1/2”
What are sites for a distal interphalangeal joint arthrocentesis ?
Dorsal parallel just proximal to coronary band
Dorsal perpendicular
Lateral
What are the landmarks for a metacarpophalangeal joint arthrocentesis ?
Collateral seasmoidean ligament approach
- joint is flexed
OR
Proximal palmar/plantar pouch approach
Cranial border: Palate palmar MC3
Plantar border: Dorsal border of suspensory lig
Proximal border: Distal border of MC4 (splint bone)
Lateral border: Proximal lateral seasmoid bone
What needle size is used to do an arthrocentesis on the stifle?
20G 1.5” needle
What two approaches are used for the stifle?
FP— lateral approch
-lateral to patellar lig and 2” dorsal to lateral meniscus insert until you feel bone
MFT
—proximal to tibia between medial patellar ligament and medial femorotibial ligament
T/F: it is best to inject all compartments when treating the stifle
True
The femoropatellar joint communicates with what compartments?
MFT (medial femorotibial ) And LFT (lateral femorotibial)
What are the landmarks for the cranial approach to the femorotibial compartments? And what size needle do you use?
Between medial and lateral patellar ligaments
Directed proximally into the trochlear groove
3” spinal needle
What landmarks do you use for a lateral approach to the femorotibial joint spaces and what needle do you use?
Caudal to the lateral patellar ligament and 6cm proximal to the lateral tibial condyle
1.5” 20g needle
(Performed with limb unloaded)
