Orthopaedics: Joint Instability Flashcards
What are the common instabilities?
- Hip luxation
- Mandibular physeal separation
- Carpal hyperextension
- Tarsal instability
- Gastrocnemius enthesopathy?
- Digit luxations
- Other luxations
What does this image show?
Hip luxation
What are the two main directions and causes of hip luxations?
Craniodorsal
* Trauma
* Dysplasia
Caudoventral
* Abduction of limb
How is hip luxation diagnosed?
Clinical signs of craniodorsal luxation
* Internal rotation of the limb
* Non weight-bearing
* Greater trochanter higher than normal
Caudoventral luxation
* Not easy clinically
* Greater trochanter lower
* pain ++
* Triangle maybe larger cf contralateral side
Confirm with orthogonal radiographs
Why is it important to know hip luxation direction?
- Clinical identification is different
- Way to reduce is different
- Post reduction stabilising techniques
How is a craniodorsal hip luxation reduced non-surgically?
- REFER TO TEXT BOOK
- GA or sedation + epidural
- Dog in lateral recumbency
- Towel/rope around inguinal area
- Externally rotate the limb to release the femoral head
- Traction caudodistally
- When femoral head distal to dorsal acetabular rim, internally rotate limb
- Immediately radiograph
Caudoventral- harder- can try to abduct again
What support is required for craniodorsal luxations and caudoventral luxations?
Craniodorsal- Ehmer sling (keep limb internally rotated)
Caudoventral- hobbles (vet wrap or custom made)
Hobbles- thinks shackles for a cow
When are mandibular physeal seperations common in cats?
How is it diagnosed?
When are radiographs needed?
Common on cats after a fall
Diagnosis
* Clinical exam- mandibular canines misaligned, excess movement
Radiographs: needed for other possible fractures
How is mandibular physeal fractures separated?
- Muzzle
- Wire- metal/PDS
Can remove 6 weeks post surgery
What does this image show?
Carpal hyperextension
What are possible causes of carpal hyperextension?
How is it diagnosed?
Causes
* High rise fall
* Degeneration
* Collateral ligament injuries
* Inflammatory disease
Diagnosis
* Clinical exam
* Radiographs- ML and DP and pes (stressed views)
How is managment of carpal hyperextension and tarsal instability decided?
- Degree of lameness
- Dysfunction
- Excercise tolerance
- Not solely on load bearing angle
Traumatic hyperextensions carpus- surgical
Tarsal instability- surgical (skin wears very quickly)
- What kind of dogs are predisposed to gastrocnemius enthesopathy?
- What is it?
- How does it present?
- How is it treated?
- Large breed dogs
- Thickened achilles tendon
- Partial or complete plantigrade stance, possible crabbed toes
- Almost always surgical
How are digit luxations treated?
Stable ones can be reduced
* Secured with splint
* P2/P3 luxations may benefit from ungunal crest ostectomy, cutting nail short
Unstable require sugery-
* Stabilisation
* Digit amputation- only one digit
