SASx Exam II Material - Distal Joints, Hip, Stifle Flashcards
T/F: TPLO and the TTA procedures for cruciate injury do not eliminate cranial drawer motion, but do provide dynamic or active constraint of drawer motion
True
T/F: With a craniodorsal coxofemoral luxation, the greater trochanter is displaced dorsally
True
-
Craniodorsal luxation
- Most common (>90%)
- Pull of gluteal muscles
- Greater trochanter displaced dorsally
What is considered the most important function of the cranial cruciate ligament?
prevents cranial tibial thrust
-
Cranial Tibial Thrust
- Naturally occurs during weightbearing
- Weightbearing creates compression across joint
- Angle between compression and tibial plateau results in shear
- Shear results in cranial force on tibia
- CCL opposes shear
List the two most common methods of screening for hip dysplasia
- Orthopedic Foundation for Animals (OFA)
- University of Pennsylvania Hip Improvement Program (PennHIP)
The patella is easily luxated and spontaneously reduces on extension. What is the grade?
Grade II
A Yorkshire terrier presents to your hospital for what you suspect is a luxating patella problem. What kind of gait or stance would confirm your suspicion?
- Bunny hopping gait
- Sits often with affected limb out
- Completely non-weight bearing
- Skipping gait
skipping gait
The treatment of choice for Legg-Perthes disease is:
femoral head ostectomy (FHO)
THR may also be considered
What breed is particularly predisposed to OCD in the tarsus?
Rottweiler
- Frequently bilateral
- Lesion is located on the ridge of the talus
- Medial – most common**
- Lateral – predominantly seen in Rottweilers (but even in Rottweilers, medial is more common)
What early radiographic change do you see with Legg-Perthes disease?
Radiopacity of lateral femoral head
Focal bony lysis (motheaten or apple core appearance)
-
Later changes
- Flattening, mottling of the femoral head
- Collapse, thickening of femoral neck
Using OFA, you cannot certify hips before ____ months
Using OFA, you cannot certify hips before 24 months
- OFA
- Single VD pelvis view; hip extended; stifles internally rotated
- 7-point ordinal scale, excellent to severe
Which of the following statements is INCORRECT regarding hyperextension injuries of the carpus in dogs?
- Pan carpal arthrodesis is the preferred treatment in most cases.
- Clinical signs include minimal pain and plantigrade stance.
- This injury results from tearing of the palmar ligaments and fibrocartilage.
- Most of these injuries can be repaired by partial carpal arthrodesis.
- Function of the carpus is nearly normal following repair in many cases.
Pan carpal arthrodesis is the preferred treatment in most cases
The single most important element for management of hip dysplasia is:
weight management
On radiographic assessment of a large breed dog’s stifle joint you see extensive periarticular osteophyte formation along the trochlear ridge of the stifle joint. The osteophytes are most likely secondary to which one of the following conditions?
- avulsion of the long digital extensor tendon
- chronic patellar luxation
- chronic cruciate ligament rupture
- idiopathic arthritis
chronic cruciate ligament rupture
What procedure is shown?
Tarsocrural arthrodesis
Tarsal hyperextension describes damage to the ________
plantar stabilizers
- Trauma
-
Chronic instability/degeneration
- Middle-aged Shelties/Collies predisposed
- Genetic weakness suspected
- May be bilateral
Identify the area of the middle carpal joint:
between first and second row
The most common injury to the canine carpus is:
hyperextension
-
Etiology
- Trauma (fall/jump)
-
Immune-mediated arthropathy
- Disease process tends to damage joint stabilizers
- Corticosteroids also tend to weaken ligaments
T/F: All carpal ligaments are short ligaments
True
They connect adjacent bones only and do not bridge more than one joint
__________ is the most commonly luxated joint
coxofemoral
-
Coxofemoral luxation
-
Usually results from trauma
- Associated with thoracic injury
- Associated with other fractures
- Treat life-threatening injuries FIRST!
-
Usually results from trauma
The medial meniscus is attached exclusively to the _______
tibia
What is this picture demonstrating?
closed reduction of craniodorsally luxated hip
What is the most common type of meniscal tear?
“Bucket Handle” tear
- Longitudinal tear in a portion of the meniscus
- Attached at each end of the tear
- When displaced looks like the handle of a bucket
-
Surgical Management
- Primary repair – not useful
-
Partial meniscectomy (most common)
- Removal of damaged portion
- Minimal change in contact mechanics Risk of postoperative meniscal injury
- Meniscal release
What presentation of cranial cruciate ligament (CCL) rupture will you see most commonly?
chronic
-
Chronic
- Progressive degeneration of CCL
- Lower breaking strength results in rupture with normal weightbearing
- CCL “disease” vs. “rupture”
-
Signalment
- Large breeds
- Rottweiler, Newfie, Staffordshire Terrier, Labrador, Mastiff, St. Bernard
- Female > male
- Neutered > intact (retrospective)
What test is being performed in this image?
tibial compression test
- Flexion of hock with stifle held at static angle mimics weightbearing force*
- Any cranial translation results in a positive test result. A positive test result indicates CCL rupture*
T/F: With a caudoventral coxofemoral luxation, the affected limb may appear longer than the non-affected limb when the dog is laid on its side
True
the femoral head is more distal than it normally is, causing the affected limb to be longer than the non-affected limb
The patella is fixed in luxation, the stifle cannot be fully extended, and the patella may be hypoplastic. What is the grade?
Grade IV
Where does OCD most commonly occur in the hock?
medial ridge of the talus
T/F: Male and female dogs are equally susceptible to developing hip dysplasia
True
Which of the following hip procedures would you select for a dog that is 7 months of age, has clinical signs of hip dysplasia, has a positive Ortolani sign, angle of reduction is 25 degrees, and no signs of DJD are seen on radiographs:
- Juvenile Pelvic Symphodesis (JPS)
- Triple Pelvic Osteotomy (TPO)
- Total Hip Replacement (THR)
- Femoral Head Ostectomy (FHO)
Triple Pelvic Osteotomy (TPO)
Is prognosis (following closed reduction) better for craniodorsal or caudoventral coxofemoral luxations?
caudoventral
- Closed reduction success
- 50% overall
- Higher if more recent injury (<24h)
- Higher with caudoventral luxation
- Lower with dysplasia, other trauma
Patellar luxation is mainly due to medial malalignment of the quadriceps, and can lead to a number of tibial and femur abnormalities later in life. What are the three main issues that we see as a result of patellar luxation?
- medial displacement of the tibial tuberosity
- abnormal (shallow) trochlear groove
- hypoplasia of medial condylar ridge
What joints are involved in a pancarpal arthrodesis?
antebrachiocarpal, middle carpal, and carpometacarpal
-
Pancarpal arthrodesis
- Antebrachiocarpal joint is abnormal
- All 3 carpal joints fused
-
DCP applied – specialized plates
- Dorsal application is typical
- Lateral application is described
- Palmar application ideal but difficult
Between craniodorsal and caudoventral coxofemoral luxation, which presents with the affected leg in relaxed extension?
craniodorsal
- Affected leg held in relaxed extension
- Foot beneath body, stifle externally rotated
- Affected leg shorter
- Loss of normal triangular relationship
- Pain/crepitus on manipulation/extension
What is the earliest radiographic finding that is indicative of hip dysplasia?
Caudal curvilinear osteophyte (Morgan’s Line)
Well defined linear density between the femoral head and the greater trochanter
Identify the area of the carpometacarpal joint:
between second row and metacarpal bones
T/F: This stance is fairly characteristic for hip dysplasia
True
-
Stance
- Rear base-wide (compensatory)
- Rear base-narrow (degeneration)
- Forward weight shift
T/F: The short and long tarsal collaterals are only taut when the joint is fully extended
False
- The long tarsal collaterals are only taut when the joint is fully extended*
- The short tarsal collaterals are taut in both flexion and extension*
What’s going on here? What are the treatment recommendations?
Carpal Laxity Syndrome
-
Treatment
- Energy-restricted diet
- Controlled exercise
- Flooring with good traction
- Should spontaneously recover in 1-4 weeks
With regard to the lateral and medial meniscus, both are attached to the tibia. Which one one is attached to the femur?
lateral meniscus
The medial meniscus is attached ONLY to the tibia
T/F: After reduction of a caudoventral coxofemoral luxation, an Ehmer splint is recommended
FALSE
- Ehmer sling is contraindicated!!*
- Apply HOBBLES for 10-14 days - they are placed at the level of the knee and prevent the limbs from sliding laterally*
Diagnosis of tarsal hyperextension is based upon:
radiographs (stress views)
T/F: A positive tarsus flexion test is diagnostic for OCD
False
A positive tarsus flexion test indicates that there is pain somewhere in the hock, but is not specifically diagnostic for OCD
A four-year-old laborador retriever presents with a weight bearing lameness in the right rear limb of five days duration. The dog has a history of bilateral hip dysplasia and occasionally bunny hops. On physical examination mild crepitation is present in the right stifle joint on flexion and extension, and a firm swelling over the medial collateral ligament area. What is the most likely cause of the dog’s lameness?
- Chronic hip dysplasia
- Patellar luxation
- Chronic cranial cruciate rupture
- Torn medial meniscus
Chronic cranial cruciate rupture
Identify the antebachiocarpal joint:
between radius/ulna and proximal row
almost all motion occurs here
T/F: After reduction of a craniodorsal coxofemoral luxation, an Ehmer splint is recommended
True
4-14 days
This hip dysplasia screening method measures distance of the femoral head center to acetabulum center:
PennHIP
- PennHIP
- Distraction applied under anesthesia
- Measure distance of femoral head center to acetabulum center
- DI=distance: radius of femoral head
- Lower DI=less laxity
- <0.3 is ideal
- Doesn’t change after 16 weeks
- Estimate of risk for OA only, not clinical signs
T/F: Once you perform a femoral head ostectomy (FHO), it is critical that the patient be cage rested for 6 weeks, after which point he should begin physical therapy and a gradual return to athletic activity.
False
Immediate post-operative limb use is essential
Juvenile Pubic Symphiodesis (JPS) is really only useful before ____ weeks of age
20 weeks
- Fuse pubic symphysis with cautery
- “Tethers” growth of pelvis
- “Rolls” acetabulum ventrally (ventroversion)
-
Only useful < 20 weeks of age
- Assess risk: PennHIP at 16 weeks
- If risk is moderate, consider JPS
- Relatively noninvasive
- Low complication rate
This is a puppy line. It is self-limiting and non-significant. There’s no question on this picture, but don’t mistake this for Morgan’s line.
The puppy line has an indistinct density and means nothing.
F*** the puppy line
T/F: With regard to the calcanean tendon, complete rupture is usually due to trauma and partial rupture is usually seen in medium-large breed dogs
True
A dog presenting with a craniodorsal hip luxation most likely will carry its leg in which of the following positions?
- Flexed and abducted
- Extended in normal walking position
- Flexed and held externally rotated
- Extended with the foot under body and external rotation of the stifle
extended with the foot under body and external rotation of the stifle
If the patella can be manually luxated but spontaneously returns to normal position, what is the grade of patellar luxation?
Grade I
For treatment of hip dysplasia, would femoral head ostectomy (FHO) and total hip replacement (THR) be considered corrective procedures or salvage procedures?
salvage procedures
-
Corrective procedures – reverse laxity
- Take advantage of skeletal immaturity
- Juvenile Pubic Symphiodesis (JPS)
- Triple Pelvic Osteotomy (TPO) (DPO)
-
Salvage procedures – preserve function
- Generally reserved for when medical tx fails
- Femoral Head Ostectomy (FHO)
- Total Hip Replacement (THR)
A positive Ortolani sign is indicative of which one of the following?
- Hip joint laxity
- Rupture of the cranial cruciate ligament
- Cranial dorsal hip luxation
- Cranial tibial thrust
Hip joint laxity
You perform a cranial drawer test on your patient and elicit a positive test on FLEXION only. What is your most likely diagnosis?
partial cruciate tear
-
Consequences are identical to complete tear
- Progresses to complete tear
- Treatment is identical to complete tear
This patient has OCD in the hock. Describe the lesion location seen in this radiograph
medial ridge of the talus
When performing a 3-loop pulley for treatment of calcanean rupture, what type of suture should you use?
monofilament non-absorbable
- The tendon has poor blood supply, so it doesn’t heal well. You need suture to stay around long enough for the tendon to heal, which can take 6-8 weeks.*
- YOU MUST ALSO IMMOBILIZE THE TARSUS IN EXTENSION WITH THIS TECHNIQUE (for up to 6-8 weeks)*
T/F: In many instances, closed reduction is indicated for dysplastic hips
False
On radiographs, femoral head coverage of >___% is considered normal.
50%
Poor coverage is associated with hip dysplasia
T/F: In a patient with hip dysplasia, you would expect palpable laxity/subluxation of the femoral head, regardless of age
False
-
Hip Dysplasia - Palpation
- Pain on extension
-
Young patient
- Palpable laxity – subluxate femoral head
- Ortolani test or Ortolani “sign”
-
Mature patient/chronic disease
- Decreased ROM in extension
- Crepitus
- No palpable laxity due to remodeling
What test is being performed in this image?
cranial drawer test
Any cranial translation results in a positive test result. A positive test result indicates a CCL rupture
Which of the following is not a histopathological change seen in hip laxity:
- Capital ligament edema
- Capital ligament thickening
- Decreased joint fluid
- Stretched capital ligament
decreased joint fluid
INCREASED joint fluid volume is expected
The back side of the canine carpus is supported by a very strong ligamentous structure called the __________ that extends from distal aspect of proximal carpal bones (radius, ulna) to the proximal aspects of the metacarpals
palmar fibrocartilage
The most common congenital deformity described in veterinary medicine is:
patellar luxation
- Small and toy breeds most affected
- 10x more likely in small breeds
- Nomenclature: position of patella
- 98% medial luxations
- 50% bilateral (often different grades)
T/F: This presentation is characteristic for a complete calcanean rupture
False
- This is characteristic for a partial calcanean rupture*
- Since the superficial digital flexor is preserved, the partially-dropped hock puts that tendon under a little bit of tension, causing the digits to flex*
A partial carpal arthrodesis involves what two joints?
middle carpal and carpometacarpal
- Antebrachiocarpal joint is normal
- Middle and carpometacarpal joints are fused using a T-plate or pins
- Function of carpus is almost unaffected – almost all motion at antebrachiocarpal joint
Closure/repair of the joint capsule is termed:
Capsulorraphy
- Simply refers to closing the joint capsule torn by the trauma
- Heavy gauge suture
- May not be possible in severe cases
- Usually insufficient as sole repair
T/F: The lateral collateral ligament consists of two components
False
- The medial collateral ligament consists of two parts (straight and oblique), so you need to take this into account when you’re performing a medial collateral ligament repair.*
- On the lateral side, there is only one (straight) component*
Complete rupture of the common calcanean tendon results in a ________ stance
plantigrade
According to PennHIP, a distraction index < ____ is ideal
According to PennHIP, a distraction index <0.3 is ideal
Essentially, every breed below a DI of 0.3 has less than a 10% chance of developing hip dysplasia
Which direction of coxofemoral luxation is the most common and how would you treat it?
- Caudoventral luxation - Reduce hip and apply an Ehmer sling for 4-14 days
- Caudoventral luxation - Reduce the hip and apply hobbles for 10-14 days
- Craniodorsal luxation - Reduce the hip and apply hobbles for 10-14 days
- Craniodorsal luxation - Reduce hip and apply an Ehmer sling for 4-14 days
Craniodorsal luxation
Reduce hip and apply an Ehmer sling for 4-14 days
T/F: The tibial compression test will test the function of the cranial cruciate ligament
True
Hip dysplasia is abnormal development of the __________ joint resulting in hip laxity
coxofemoral
At what levels of the tarsus do we typically see hyperextension injury?
proximal intertarsal and tarsometatarsal
