Stifle Joint Flashcards
Is Osteochondrosis/osteochondritis dissecans of the stifle joint often unilateral or bilateral?
Bilateral
Which surface of the stifle is commonly effected by Osteochondrosis/osteochondritis dissecans of the stifle joint?
Medial surface of lateral femoral condyle
How common are isolated tears of the medial or lateral collateral ligaments?
Rare - usually occur in conjunction with injury of other primary or secondary stabilisers of the stifle joint.
What type of joint is the stifle?
A complex condylar synovial joint
How many articular regions does the femur have?
3
What do the femoral lateral and medial condyles articulate with?
Proximal tibia
In cross section, what shape is the proximal tibia?
Triangle
What does the femoral trochlea articulate with?
Patella
How is the articular surface of the proximal tibia composed?
Two condyles, the lateral and medial separated by the non-articular intercondylar eminence
What lie on and are attached to their respective medial and lateral tibial condyles of the proximal tibia?
Medial and lateral menisci
What does the head of the fibula articulate with?
Caudo lateral surface of lateral tibial condyle
What is the largest sesamoid of the body?
Patella
What is the patella found within?
Tendon of insertion of the quadriceps muscle group
The patellar ligament runs from the paterlla to insert where?
On tibial tuberosity
What are the three other sesamoid bones of the stifle? Where are they?
These include the medial and lateral fabellae, which are within the medial and lateral heads of the origin of the gastrocnemius muscle, and the popliteal sesamoid, which is within the tendon of origin of the popliteus muscle at the lateral condyle of the tibia.
What are the 3 articulations of the stifle?
femorotibial joint,
the femoropatellar joint
the tibiofibular joint.
How many ligaments give primary support to the stifle?
4
What are the support ligaments of the stifle?
the medial and lateral collateral ligaments
cranial and caudal cruciate ligaments.
Which stifle ligament has strong attachments to the medial meniscus
Medial collateral ligament
What are the menisci attached to the tibi by?
Series of pairedd ligaments - the cranial and caudal meniscotibial ligaments of each menisci.
he meniscofemoral ligament of the lateral meniscus runs from and to?
From: caudal axial border of the lateral meniscus
To: the intercondylar fossa of the femur
The intermeniscal ligament is a fibrous band that extends from and to?
From: caudal side of the cranial tibial ligament of the medial meniscus
To: the cranial side of the cranial tibial ligament of the lateral mensicus.
Are cruciate ligaments intra or extra articular?
Intra articular
Are the cruciate ligaments intra or extra synovial?
Extra synovial
The cruciate ligaments are termed cranial or caudal based on….?
Tibial attachment
What does the cranial cruciate ligament prevent?
Cranial translation of the tibia
What are the two bands the cranial ligament are split into? Which is larger?
Caudolateral (larger)
Craniomedial
Is the cranial or caudal cruciate ligament larger?
Caudal
There is no cranial drawer with partial ruptures if only the A) band is torn as the B) band stabilises the stifle in both flexion and extension.
A) Caudolateral
B) Craniomedial
If only the A) band is torn there is cranial drawer when the stifle is flexed as the B) band only stabilises the stifle in extension. For this reason, it is important to assess craniocaudal stifle stability in both flexion and extension.
A) Craniomedial
B) Caudolateral
What does the caudal cruciate ligament prevent?
Caudal translation of tibia
What shape and material of the menisci of the stifle?
C shaped
What cross section shape is the stifle meniscus?
Wedge shape
Where is the mensicus of the stifle:
A) Thick?
B) Thin?
A) Thick - where attached to synovium
B) Thin - free edge axially
How much of the mensicus has a blood supply - where does this originate?
Peripheral 15-25% Originating from synovium
What forces develop from the shape and near frictionless surface of the meniscus developing from compressive forces?
Radial forces
How are the radial forces of the meniscus resisted?
Tensile (hoop) stress in the circumferentially arranged collagen fibres of the menisci
What are the roles of the menisci of the stifle? (2)
- 2ry stabiliser
- Transfer load across stifle
What does the function of the stifle menisci rely on?
Intact peripheral rim (hoop stress)
What are the 2 surgical approaches to the stifle?
Lateral and medial
When approaching the stifle on the lateral aspect, take care to avoid injury to which structure when entering joint capsule?
Long digital extensor tendon
On the lateral approch to the patella; which way is patella luxated?
Medially
Which of the following statements pertaining to the long digital extensor muscle is correct?
A) It originates at the extensor fossa of the lateral femoral condyle and inserts on digits II through V and its origin is intra-articular.
B) It originates at the extensor fossa of the lateral femoral condyle and inserts on digits II through V and its origin is extra-articular.
C) It originates at the extensor fossa of the medial femoral condyle and inserts on digits II through V and its origin is intra-articular.
D) It originates at the extensor fossa of the medial femoral condyle and inserts on digits II through V and its origin is extra-articular.
A) It originates at the extensor fossa of the lateral femoral condyle and inserts on digits II through V and its origin is intra-articular.
Lateral approach to the stifle:
A) Where is the skin incision? Including where it is extended to?
B) How is the lateral fascia incised?
A) Make a skin incision over the tibial tuberosity lateral to the patellar ligament and continue it proximally to the level of the patella and above following the cranial border of the femur.
B) starting opposite the distal pole of the patella and a few millimetres lateral to the patellar ligament and continuing distally to the tibia
During the lateral approach to the stifle, where is the stab incision in the stifle joint made to avoid damaging articular cartilage of the femoral condyle?
Into stifle joint at proximal end of incision
During the lateral approach to the stifle - One blade of a scissor is inserted into the joint and the scissor is advanced proximally, cutting? (3)
Joint capsule
Lateral parapatellar fibrocartilage
Fascia lata
During the lateral approach to the patella, we must ensure enough tissue is left on the LATERAL side of the joint capsule; for what reason?
Permit suturing
Lateral approach to the stifle; upon moving the patella medially; what should you do if this does not stay in place?
Extend the proximal end of the incision
After the movement of the patella medially on the lateral approach to the stifle; what exposes the cruciate ligaments and menisci?
Distal retraction of the fat pad.
After the lateral approach to the stifle - how is The joint capsule and lateral fascia of the stifle joint closed?
1 layer - continuous or interrupted.
Medial approach to the stifle:
Where is the skin incision?
A craniomedial incision is made and centred at the level of the patella.
The incision should start 5cm proximal to the patella and continue distally 5cm below the tibial crest.
On the medial approach to the stifle after the subcut tissue is incised - what is exposed?
parapatellar medial retinaculum
On the medial approach to the stifle - where is the joint capsule incised?
Medial ridge of paterllar tendon
On the medial approach to the stifle - where is the joint capsule incision continued to:
A) Proximally?
B) Distally?
A) Suprapatellar joint
B) Tibial tuberosity