Hindlimb Lameness- Stifle Joint

Question 1

What is the most common cause of Hindlimb lameness in dogs?

Answer 1

Cranial cruciate ligament disease

Question 2

Are there any predispositions to Cranial cruciate ligament disease?

Answer 2

Can occur in any breed (but not really greyhounds lol)
But neutered females and obese dogs generally more at risk

Question 3

What are the three types/ causes of cranial cruciate ligament disease?

Answer 3

Traumatic avulsion
Traumatic rupture
Degenerative Weakening (this is the major pathogenesis)

Question 4

What disease can Cranial Cruciate Ligament Disease lead to?

Answer 4

Arthritis because the joint becomes unstable

Question 5

What is the role of the Cranial Cruciate Ligament? (3)

Answer 5

Knee stability
Allows craniotibial translation (internal rotation)
Also stops the stifle joint falling backwards by attaching the front and back of the joint together

Question 6

50% of dogs with Cranial Cruciate rupture also have damage to the …

Answer 6

Meniscus (medial)

Question 7

What do the Meniscus have that allow load bearing/ shock absorbtion?

Answer 7

Collagen fibre arrangement converts compression into tension

Question 8

Where do the Meniscus attach?

Answer 8

Medial- attaches to the Tibia
Lateral- attaches to the femur

Question 9

How will an animal with Cranial Cruciate Ligament Disease present?

Answer 9

Lameness or non weight bearing with an unwillingness to flex the stifle
May sit with the leg extended or out to the side

Question 10

What are we paying attention to when examining the stifle? (5)

Answer 10

Effusion- should be firm with clear ligament boundaries- if not then suggests fluid
Medial Buttress- feel medial side of femur- if one side is bigger it suggests fibrous tissue deposition
Patellar Tracking
Range of Motion
Pain

Question 11

What two tests do we perform on the stifle to assess stability of the joint?

Answer 11

Cranial Draw (sliding of the patella)
Tibial Thrust (mimics walking)

Question 12

What diagnostic tests can we undertake to diagnose Cranial Cruciate Ligament Disease?

Answer 12

Radiographs- multiple views!
MRI/ Contrast CT
Arthroscopy for surgical confirmation

Question 13

How should we treat Cranial Cruciate Ligament Disease?

Answer 13

Conservative management (not preferred)- if no response after 8 weeks than surgical stabilisation
Dogs with meniscal injuries definitely need surgery!

Question 14

What three types of surgery can we perform to correct Cranial Cruciate Ligament Disease?

Answer 14

Intra articular
Extra articular
Osteotomy

Question 15

Briefly describe the process of Intra articular surgery to treat Cranial Cruciate Ligament Disease?

Answer 15

It’s a type of Graft through the bone tunnels- Take fascia from inside the joint, run it through the tunnels and fix it with screws

Question 16

How does Extraarticular surgery differ from Intraarticular?

Answer 16

Extraarticular- Band is placed on the OUTSIDE of the joint- it remains and provides stability until scar tissue forms
This method is preferred over Intra articular!!

Question 17

What material is used for Extra articular surgery and how long does it last?

Answer 17

Metal wire e.g. Nylon
Breaks in 6-8 weeks

Question 18

What is the aim of an Osteotomy to correct Cranial Cruciate Ligament Disease?

Answer 18

works on the basis that the femoral condyle is like a ball rolling down the tibial slope so if you flatten the slope then the knee is more stabilised and the tibial thrust neutralises

Question 19

What is the prognosis of an Osteotomy?

Answer 19

Has a more rapid return to function than other surgeries especially for large breeds
But it is an advanced surgical technique

Question 20

What should we warn owners about after we have treated the initial Cranial Cruciate Ligament Disease? (2)

Answer 20

50% of dogs will get a bilateral rupture in the next 2 years
And Osteoarthritis will progress irrespective of treatment

Question 21

What is a patella luxation?
Is it developmental or congenital?

Answer 21

Abnormal tracking of the patella
Developmental disorder

Question 22

What can cause the patella luxate? (3)

Answer 22

• Problems with quadricep mechanism- could be due to hip/femoral neck development which causes the quads to deviate
• Uneven pressure on the physes which alters growth dynamics
• Boney deformation

Question 23

How common are patella luxations in domestic/ pet species?

Answer 23

Common cause of INTERMITTENT lameness in young, small dogs
Can occur in cats but usually not clinical because cats have very mobile patellae

Question 24

What is the key clinical presentation of a patella luxation?

Answer 24

Skipping Lameness- intermittent non weight bearing

Question 25

On a clinical examination, what would we expect to see if the animal has a patella luxation?

Answer 25

Muscle atrophy with possible effusion No tibial thrust or cranial draw If you can push patella out of groove- abnormal Retropatellar/ luxation pain

Question 26

Briefly explain how we grade a Patellar Luxation.

Answer 26

Grades I- IV with IV being most painful and severe With I being the patella returns in normally after being pushed out II- Stays out when pushed out III- When patella is out normally but can be returned in with force IV- when patella is out normally and cannot be returned in at all

Question 27

When would we NOT perform surgery in cases of patellar luxation?

Answer 27

Low grade luxation's- with no lameness, discomfort or highly infrequent skipping lameness

Question 28

When is surgery indicated to fix a patellar luxation?

Answer 28

All Grade IV's and III Or mild luxation's that have pain, pressure and frequent lameness

Question 29

What can we do surgically to deepen the groove of the patella? Give 2.

Answer 29

Trochleoplasty- rasp off cartilage, but can encourage fibrocartilage formation Chondroplasty- elevate cartilage flap to remove underlying bone (only animals <6months old) Wedge Recession Sulcoplasty- Cartlidge and bone removed Block recession Sulcoplasty- like wedge recession but do a whole block -better results but difficult to perform

Question 30

What may we also have to perform whilst the patient is undergoing surgery to fix the patellar luxation? Hint- think ligaments to better aid outcome

Answer 30

Tibial Tuberosity Transposition- straighten femur and tibia with pin and tension band wire

Question 31

What sutures are used to tighten and close the surgical sight in a tibial tuberosity transposition?

Answer 31

Modified mayo mattress suture- basically one tissue is sutured over the other to provide stability

Question 32

When is a tibial tuberosity transposition contraindicated and why?

Answer 32

In skeletally immature patients (younger than 10 months)- may lead to abnormal distal positioning of the patellar tendon and therefore patella fractures later in life