Page 226 - WSAVA2018
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 25-28 September, 2018 | Singapore
M. Glyde1
1BVSc MACVSc MVS HDipUTL Diplomate ECVS, College of Veterinary Medicine. Murdoch University
Learning Objectives
At the end of this session you will be able to:
· Identify the instruments that simplify stifle joint explo- ration and how to use them
· Recognise differences between the medial and lateral menisci
· Identify the location of a meniscal injury
The keys to simplifying stifle joint surgery are an
understanding of:
· the surgical anatomy of the stifle joint – familiarity with surgical anatomy aids confidence, intraoperative decision-making and simplifies surgery overall
· the preparation, positioning and intraoperative manipulation of the stifle joint that will simplify stifle joint exposure and maximize visualization
tively examine the joint structures
· common surgical procedures involving the stifle joint
Preparation and positioning
Surgical preparation and draping are most easily performed with the limb suspended with adhesive tape from a drip stand or roof bolt. The limb should be clipped circumferentially from the proximal thigh to just proximal to the hock joint for most stifle joint surgeries. After routine surgical preparation the animal can be moved into the operating room with the limb still suspended.
Positioning the animal in dorsal recumbency simplifies stifle joint exploration. “Free draping” rather than field draping will allow the surgeon to have maximum vision and intraoperative manipulation of the stifle joint.
It is important that the final drape layer is of waterproof material as lavage is necessary in most stifle joint surgeries. Non-waterproof drapes will increase the risk of bacterial contamination through strike-through.
Equipment for effective stifle joint exploration includes:
· 1 Gelpi self-retaining retractor
· 1 stifle joint distractor (or alternatively a narrow-blad-
ed 10-12mm Hohmann retractor
· 1 sharp-pointed Senn retractor
· 1 meniscal probe
· 1 mosquito haemostat or meniscal forceps
· Frazier suction tip (#6 or 8) and suction
· effective surgical lighting
· sterile lavage solution
Surgical approach for stifle joint exploration
The specifics of the various surgical approaches to
the stifle joint are beyond the scope of this session. Arthroscopy has been shown to provide superior meniscal detail, greater sensitivity in detecting meniscal damage, reduced patient morbidity and a significantly lower occurrence of late or subsequent meniscal injury than for arthrotomy.
This session will focus on arthrotomy. Both the lateral and medial approaches have relative advantages and disadvantages. Both provide equally good vision and access to the menisci. Which side the surgeon chooses is personal preference and is usually determined by the type of cruciate stabilization surgery that is to be performed.
In both cases a “mini arthrotomy” rather than a full arthrotomy is completely adequate to provide adequate visualization to confirm the presence of cruciate disease and explore the menisci and adequate access for any necessary meniscal surgery.
The mini arthrotomy incision is from the level of the distal pole of the patella to the tibial plateau. Recognise that the infrapatellar fat pad is cranial to or outside the synovial part of the joint, so it is not necessary to incise through the fat pad. The incision through the synovial membrane runs immediately proximal to the fat pad and extends proximally to the level of the distal pole of the patella.
In a typical cruciate disease case there is chronic thickening of the synovial membrane and so the use of electrosurgery to control small arterial vessels in the thickened capsule in combination with suction is very useful.
A Gelpi retractor is inserted to transversely retract the capsular incision.
To properly inspect the menisci when cranial cruciate ligament rupture exists and the joint is unstable it is essential that distraction or cranial drawer of the tibia is achieved and maintained throughout the procedure.
Effective inspection of the menisci when no cruciate instability is present is not possible without arthroscopy. It should be noted that when no instability exists such as in early cases of cruciate disease it is very uncommon to have isolated meniscal injuries that are significant.
In these cases where there is no instability in either flexion or extension when examined under general anesthesia it is reasonable to assume that there is no significant meniscal injury. An arthrotomy (or arthroscopy) to confirm that early cruciate disease with partial tearing of the cranial cruciate ligament is present however would be necessary. Careful probing of the cranial cruciate ligament with the meniscal probe will usually identify torn cruciate fibres in these cases.
  · the equipment that will simplify exposure
· how to perform a stifle joint arthrotomy and effec-

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