Lecture 9: Cranial Cruciate Ligament Injury/Dx III (Exam 2)

Question 1

What is involved for extracapsular reconstruction

Answer 1

Placement of sutures outside the joint or redirections of the lateral collateral lig

Question 2

What significantly effects the isometry of the joint? What does it affect?

Answer 2

• Location of the origin & insertion of the extracapsular suture
• Affects the amount of drawer motion throughout norm range of motion of the stifle

Question 3

What can extracapsular sutures also be secured from

Answer 3

• Bone Anchors
• Bone Tunnels

Question 4

What materials are used in extracapsular sutures

Answer 4

• Monofilament nylon or fishing/leader line
• Manufactured ortho wire
• Braided ortho suture

Question 5

In extracapsular reconstruction how are sutures tied/connected

Answer 5

W/ a crimp to alter the biomechanical props of the loop

Question 6

What is this

Answer 6

Question 7

What is this showing

Answer 7

Tightrope stabilization

Question 8

What is the true imbrication tech

Answer 8

• Performed by tightening fascia lata
• Usually in addition to another tech

Question 9

What is the function of the cranial cruciate lig

Answer 9

Passive constraint to the cranial tibial translation & internal rotation of the tibia

Question 10

What occurs if there is a larger tibial plateau angle

Answer 10

The greater the cranial force there is on the tibia during wgt bearing

Question 11

Describe the vector force that occurs in the tarsus

Answer 11

• Sum of resulting forces of wt bearing
• Creates a simultaneous force through the patellar ligament & stabilizes the stifle

Question 12

What happens if the slope of the tibial plateau is NOT anatomically oriented perpendicular to the patellar lig on wt bearing

Answer 12

• Caused tibiofemoral shear force that causes a cranial tibial thrust force (CTT) in the direction of the cranial drawer or tibial translation
• CCT force is accommodated for an in norm animal by the CCL

Question 13

What happens when the tibia is loaded

Answer 13

• Caudally directed slope of the tibial plateau results in a shear force
• Creates abnorm tibial translation in CCL deficient stifle joints

Question 14

What is the cranial tibial thrust (CTT)

Answer 14

The shear component of compressive force (normally passively constrained by the CCL)

Question 15

T/F: CTT is inproportional to the slope of the cranial tibial plateau

Answer 15

False they are proportional

Question 16

What happens if the tibial plateau slope is reduced

Answer 16

The tibial thrust changes from a cranioproximal direction to a neutral or caudal direction

Question 17

What causes increase reliance on the caudal cruciate lig

Answer 17

A point where tibial thrust changes direction to a caudal thrust

Question 18

What is the intent of the tibial plateau leveling osteotomy (TPLO) sx

Answer 18

• Attain a tibial plateau slope of approx 5 to 7 degrees
• Where tibial thrust can be controlled by the caudal cruciate lig & active constraints of the stifle (the quad musces)

Question 19

What is a “Pivot Shift”

Answer 19

Failure to control internal rotation resulting in drawer w/ internal rotation

Question 20

Who is TPLO preferred for txing

Answer 20

• Larger active dogs
• Long term rehab & post op control is diff

Question 21

What is this showing

Answer 21

Question 22

What is this showing

Answer 22

Question 23

What is this Xray showing

Answer 23

Before & after of an AP TPLO

Question 24

What is associated w/ complications of the stifle extensor mechanism

Answer 24

Lower osteotomy results in change of the relative position of the tibial crest

Question 25

What is an Tibial Wedge Osteotomy (TWO)

Answer 25

A technique for management of the CCLR & increased TPA in young dogs w/ open proximal tibial physes

Question 26

T/F: TWO will not affect physes as the TPLO

Answer 26

True

Question 27

What does the Tibial Tuberosity Advancement (TTA) do

Answer 27

Positions the patellar lig 90 degree to slope of the tibial plateau by advancing insertion in the cranial direction to elim tibiofemoral shear force w/ wt bearing & relieves function of the CCL

Question 28

TTA theoretically (reduces/increase) patellar lig tension while a TPLO (reduces/increases) patellar lig tension

Answer 28

Reduces; increases

Question 29

What procedure has less postoperative patellar lig inflammation than a TPLO

Answer 29

TTA

Question 30

Describe the biomechanics of TTA

Answer 30

* TTA places patellar lig 90 degree to slope of the tibial plateau * By advancing insertion in cranial direction * Eliminates tibiofemoral shear force w/ wt bearing & relieving fxn of the CCL

Question 31

What is this illustrating

Answer 31

TTA

Question 32

What is this showing

Answer 32

CBLO

Question 33

Regardless of the tech used what should be done during sx tx of a ruptured CCL

Answer 33

* Meniscus inspected by arthrotomy or arthroscopy * ID tears or other evidence of trauma

Question 34

What % of pxs w/ torn CCLs have damage to the caudal body of the medial meniscus

Answer 34

50 to 70%

Question 35

Who need thorough eval for potential complication following CCL repair

Answer 35

Px w/ poor outcome

Question 36

What is the prognosis of long term fxn for px that have had CCL sx

Answer 36

Good

Question 37

What is the % of dogs that improve after sx

Answer 37

85 to 90%

Question 38

T/F: DJD can be stoped by tx

Answer 38

F is progresses regardless of tx

Question 39

What is the long term outcome w/ CCL sx

Answer 39

* Decline in activity over time * Increasing level of disability * Adverse response to cold weather * Stiffness after inactivity due to progress of DJD