Misc orthopedic conditions Flashcards
CARPAL LAXITY OR DEVELOPMENTAL HYPEREXTENSION
- clinical signs
> 2 forms
- age, breeds
- cause
2 forms:
* Hyperextension
> Carpal plantigrade stance
* Hyperflexion
> tightness of the flexor muscles
<><>
* No pain or swelling
* Normal radiographs
<><>
6-12 weeks of age
* Dobermans, German Shepherd Dogs and Great Danes, others…
<><>
Cause?
* Imbalance between growth and muscles
tendons/ligaments strength or length
* Nutritional imbalances (high proteins?)
* Genetic
CARPAL LAXITY OR DEVELOPMENTAL HYPEREXTENSION
- Tx, prognosis
Treatment
* Moderate activity on tractable surface
* Good plane of nutrition: Avoid OVER nutrition
* Rehabilitation
* NO supportive bandage or splint: unless absolutely necessary
<><>
Prognosis
* Generally very good
* Spontaneous resolution in 2-4 weeks for mild to moderate cases
CARPAL / TARSAL HYPEREXTENSION INJURY
- causes
- what happens
- concurrent issues
Causes
* TRAUMA (jump or fall from a height, HBC)
* Degenerative (especially Shelties and Collies)
<><>
* Rupture of the palmar carpal/tarsal ligaments and palmar fibrocartilage
<><>
± Concomitant injuries
* Metacarpal fractures (especially II and V)
* Collateral ligament rupture
CARPAL / TARSAL HYPEREXTENSION INJURY
- clinical signs
- Carpal/Tarsal hyperextension
- Severe pain if acute
- Moderate weight bearing pain if chronic or degenerative
- Unilateral or bilateral
<><> - Carpal / Tarsal swelling and periarticular thickening
CARPAL / TARSAL HYPEREXTENSION INJURY
- Dx
Palpation
* Hyperextension
* Valgus-varus deformity
* Excessive rotation
<><>
Radiographs
* Rule-out/diagnose fractures
* Stress radiographs must be performed
> Determine level of joint and ligaments involved
CARPAL / TARSAL HYPEREXTENSION INJURY
- Tx options, efficacy?
Conservative management (splint)
* Ineffective
* Ruptured palmar fibrocartilage does not return to sufficient strength to prevent recurrence
* Recurrence very common
<><>
Surgical treatment
* Pancarpal or Pantarsal arthrodesis
* ± Partial Carpal or Tarsal arthrodesis
> ONLY if main joint intact! (radio-carpal or talo-crural)
* Very good prognosis
Pan- or Partial Carpal Arthrodesis
- what do we do?
- prognosis?
- Remove all articular cartilage
- Cancellous bone graft in joint spaces
- Strong bone plate
- Splinting until radiographic of arthrodesis (6-12 weeks)
<><>
Prognosis - Good to very good
- Once healed…
- High complication rate (mostly due to bandages)
panosteitis
- pathophysiology
- etiology?
- who is affected?
- Unknown: Necrosis and inflammation of fatty bone marrow
- Genetics? Young, Large breed dogs (especially German Shepherd Dogs)
<><>
Other ? - Vascular abnormality?
- Viral infection?
- Hormonal?
- not bacterial, parasitic, or allergic
panosteitis clinical signs
- age
- sex
- size, breed
- presentation
- physical exam
- 5-18 months
- Male>female 4:1
- Large breed dogs
- Acute onset of lameness (without trauma)
> Forelimbs usually affected first
> Pelvic limb can also be affected
<><> - Shifting lameness for 14-21 days
- Severe pain on palpation of diaphyseal bone
- ± Pyrexia, anorexia and lethargy
panosteitis Dx
- RADIOGRAPHS
- Increased radiodensities in the medullary canal starting at the nutrient foramen and then becoming multifocal and coalescing
> Loss of definition between medullary canal and cortex
> Endosteal roughening with coarse trabecular pattern - Radiographic signs persist longer than clinical signs
panosteitis Tx, prognosis?
Supportive
* Rest
* ± NSAIDs
<><>
Prognosis
* 10-15 days episode(s)
* Self-limiting by 12-20 months
* Very good to excellent
Metaphyseal Osteopathy
- pathophysiology / causes?
- who is affected?
- Disturbance of the metaphyseal blood supply leading to failure in ossification of the growth plate
- Unknown
- Genetics?
> Large to giant breed dogs
> Especially Weimaraner, Setters, Great Danes
> 3-6 months of age
<><><><> - Modified-live virus vaccination?
> Has been observed after vaccination - Infection (distemper)?
> Viral DNA has been isolated
> Does not mean it caused it…
Metaphyseal Osteopathy
- clinical signs
- Acute swelling of distal extremities
> Distal metaphyseal region
> Warm
> Very Painful - Bilateral ± all four limbs
- Lameness variable (mild to recumbent)
<><> - Pyrexia ± anorexia and depression
- ± Upper respiratory tract infection and diarrhea
> Week preceding lameness
Metaphyseal Osteopathy
- Dx
- RADIOGRAPHS
- Radiolucent line adjacent to physis (pathognomonic)
> “Double growth plate” - Metaphyseal flaring
- ± Premature physeal closure
Metaphyseal Osteopathy
- treatment and prognosis?
Supportive
* NSAIDs
* Corticosteroids > NSAIDs and morphinics for peracute cases
* Intravenous fluids, enteral nutrition and well- padded bedding
<><>
Prognosis
* Good to excellent in majority of cases
* Guarded for severely affected dogs with peracute presentation
HYPERTROPHIC OSTEOPATHY (HO)
- pathophysiology
- Peripheral vasodilation of the distal extremities which stimulates connective tissue and periosteal proliferation
- Cause of peripheral vasodilation unknown
> Neural stimulation (vagal nerve)
Intrathoracic disease (most often)
=> Metastatic neoplasia most common (> 90%)
=> Primary neoplasia (lungs and chest wall)
=> Lung abscess and pneumonia
=> Esophageal granuloma
=> Heartworm disease
HYPERTROPHIC OSTEOPATHY (HO)
- clinical signs
- Acute onset of lameness
- Reluctance to move
- Bilaterally symmetrical involvement of all 4 limbs
- Painful swelling of the extremities
- ± Pyrexia
HYPERTROPHIC OSTEOPATHY (HO)
- Dx
DIAGNOSIS - LIMB and thoracic RADIOGRAPHS
HYPERTROPHIC OSTEOPATHY (HO)
- treatment
- prognosis
Curative-intent treatment
* Removal of primary cause (metastatectomy)
<><>
Palliative treatment for tumours
* Chemotherapy
* Palliative radiation
* NSAIDs
* Bisphosphonates…
<><>
Prognosis poor
* lesions regress but die from primary disease
PREMATURE PHYSEAL CLOSURE
- pathophysiology
- most commonly affected anatomic location
- Radius-ulna is a paired bone system
- Growth of a paired bone system is synchronous but proximal and distal physes of each bone contribute different proportions to bone growth
- Distal ulna is most commonly affected
> Only growth plate responsible for length of the
ulna below the joint
> Conical shape of the distal physis?
DISTAL ULNAR PHYSEAL CLOSURE
> what happens? what is the problem?
- Ulna restricts growth of the radius
> Bowstring effect? - Carpal abnormalities
> Bowing of radius
> Valgus deformity carpus
> External rotation - Elbow abnormalities
> Humeroulnar subluxation
> ± Ununited anconeal process
PREMATURE PHYSEAL CLOSURE
- treatment options for immature dog
> aims
> timing
> techniques
Aims
* Prevent further bone deformation
* Prevent joint subluxation
* MAY correct mild deformities
> Bone must “grow out” of the deformity
> ONLY immature with growth potential
<><>
Must be done quickly!
* Before severe deformity
* Before elbow subluxation
<><>
Surgical techniques
* Segmental distal ulnar ostectomy
PREMATURE PHYSEAL CLOSURE
- treatment for a mature dog
> aims
> techniques
Aims
* Correct bone deformities
* Facilitate ambulation
* Improve cosmetic appearance
* Minimize progressive carpal and elbow osteoarthritis
<><>
Surgical techniques
* Definitive corrective radial osteotomy (ies)
COLLATERAL LIGAMENT INJURY (SPRAIN)
- gradings and treatments
Grade I
- Lesion: Fibre rupture with minimal instability
- Treatment: Conservative
<><>
Grade II
- Lesion: Partial ligament rupture with severe fibre stretching
- Treatment: Surgical or Conservative +Splinting
<><>
Grade III
- Lesion: Complete ligament rupture
- Treatment: Surgical + Splinting
COLLATERAL LIGAMENT INJURY (SPRAIN)
- pathophysiology
- Trauma (especially jumps, fall, HBC)
- Medial collateral ligaments more commonly injured than lateral
- May be associated with fractures !
- Must rule out possible concurrent hyperextension
COLLATERAL LIGAMENT INJURY (SPRAIN)
- clinical signs
- Dx
- Clinical signs
> Non-weight bearing lameness
> Joint swelling - Collateral ligament assessment
> Valgus and varus forces applied while the carpus is in extension and flexion - Palmar ligament assessment
- Radiographs
> Dorsopalmar and lateromedial ± oblique projections > Stress projections
PROSTHETIC COLLATERAL LIGAMENT
- what do we do?
- post op management
- prognosis
- Ligament is replaced using heavy suture between bone screws or anchors
- Primary repair may be attempted in addition but not often possible
<><>
Postoperative management - Immobilization in a splint / Cast for 4-6 weeks
> Must be partially loaded at 4 weeks to orient collagen fibers - Activity restricted to leashed walks for 12 weeks
<><>
Prognosis - Good if no other significant injuries
- Decreased range of motion and osteoarthritis
- Prognosis depends on intended use of animal
SHEARING INJURIES
- pathophysiology, type of injuries seen
- Degloving injury caused by low velocity shearing forces
- Skin disruption mechanical and physiological with crushing and avulsion injuries
- Heavily contaminated with open joints and fractures
- Concurrent injury common
shearing injuries treatment
- how do we manage
- long term?
Temporary Stabilization
> Splints or external fixators
<><>
* Analgesia
<><>
Wound management
* Daily or twice daily initially (7-10 days…)
> Debride
> Lavage
> Bandage
(2nd intention healing)
<><>
Excellent wound care and bandage care is ESSENTIAL
<><><><><>
Additional Surgeries
* Further debridement
* Permanent stabilization
* Skin grafting
> Accelerates the wound care
<><>
* On average, 1.8 surgeries are required…
* Requires a strong commitment from owner and Vet
> Time, $$$
shearing injury prognosis
* Bone or joint exposure or joint instability
* No bone or joint exposure or joint instability
- other options?
Bone or joint exposure or joint instability
* > 75% good to excellent outcome
* Mean healing time 7 weeks
<><>
No bone or joint exposure or joint instability
* > 90% good to excellent outcome
* Mean healing time 3
<><>
* Decision to amputate versus treat is often financial
