Elbow Joint – Developmental Elbow Disease Flashcards
Pathologies of the medial coronoid process, osteochondritis of the medial aspect of the humeral condyle and elbow joint incongruity often occur simultaneously, all affect which compartment of the elbow?
Medial
What term currently used to summarise pathologies of the medial coronoid process?
Medial coronoid process disease (MCPD)
What are the 4 pathologies of the medial coronoid process?
Fissuring or fragmentation of the medial coronoid process;
Cartilage damage to the medial coronoid process;
Coronoid microfracture;
Medial coronoid process sclerosis.
What are proposed causes of the aetiology of medial compartment disease? (6)
Genetics
Nutritional excess
Nutritional deficiency
Growth disturbance
Osteochondrosis
Trauma
What is different about the ossification centre of the medial coronoid process? How does it ossify?
There is no ossification centre
Ossification via appositional ossification
The presence of what in the trabecular bone of affected coronoid processes have been suggested as evidence that fatigue microdamage of the underlying subchondral bone due to excessive loading plays an important role in the pathogenesis of medial coronoid process disease?
Micro cracks
During the medial approach to the elbow, what will need to be ligated?
The intermuscular branch of the recurrent ulnar artery and vein
Signalment for medial compartment disease:
A) Sex?
B) Age?
C) Breed size?
A) Male (2:1)
B) Young
C) Large - giant
Which breeds are predisposed to medial compartment disease? (4)
- Labrador
- Rottweiler
- GSD
- Bernese Mountain dog
Joint incongruity occurs in ? of elbows with medial coronoid process disease.
60%
What is the age of presentation for medial compartment dx?
6-18 mo
What is the incidence of bilateral medial coronoid process dx?
25-80%
Traditionally, three types of elbow joint incongruity were described. Can you guess them?
Radioulnar incongruity (e.g. short ulna or short radius).
Humeroulnar incongruity (e.g. abnormal shape of the ulnar notch).
Humeroradial incongruity.
How does the lameness present with MCD?
age? worse?
Forelimb lameness is usually present for several months beginning at 4 to 12 months of age, however, younger dogs and dogs as old as eight
The lameness is gradual and progressive and usually worse after exercise. Other signs of MCD include short striding and difficulty in rising or lying down.
Most dogs with MCD sit or stand with the elbow A) and the carpus B)
A) Abducted
B) Adducted
What is found on palpation of the elbow with MCD? (4)
- ST swelling
- Muscle atrophy
- Pain
- Crepitus
What specific aspects of lameness exam should be performed for MCD? (3)
Walk
Trot
Circling in a figure of 8
What is the normal weight distribution to the FLs?
60%
What weight distribution is seen in dog with MCD on the FLs?
40-50%
What radiographic views are needed to evaluate of MCD?
Craniocaudal;
Mediolateral;
Flexed mediolateral;
Craniocaudal medial-to-lateral oblique with the elbow maximally extended and supinated;
Medio-distal to latero-proximal oblique view is also helpful in some cases
What is IEWG?
International Elbow Working Group (IEWG) Grading system for Developmental Elbow Disease.
IWEG score - 0:
A) What degree of dx is this?
B) Radiographic findings?
A) Normal
B) Normal
IWEG score - 1:
A) What degree of dx is this?
B) Osteophyte Radiographic findings?
C) Sclerosis?
A) Mild
B) Osteophytes < 2 mm
C) Subtrochlear sclerosis with trabecular pattern
IWEG score - 2:
A) What degree of dx is this?
B) Osteophyte Radiographic findings?
C) Sclerosis?
D) Radioulnar step?
A) Moderate
B) Osteophytes 2-5 mm
C) Subtrochlear sclerosis without trabecular pattern
D) Radioulnar step 3-5 mm
IWEG score - 3:
A) What degree of dx is this?
B) Osteophyte Radiographic findings?
C) Sclerosis?
D) Radioulnar step?
A) Severe
B) Osteophytes >5 mm
C) Subtrochlear sclerosis
D) Radioulnar step >5 mm
What are the conservative management options for MCD? (5)
might include weight control, exercise management, multimodal analgesia, physio/hydrotherapy and nutraceuticals
In MCD cases where conservative treatment fails, what should be considered?
arthroscopic fragment retrieval and/or subtotal coronoidectomy (SCO)
When might biceps ulnar release be considered in MCD cases?
BURP might be considered in cases with suspected radio-ulnar conflict. It is currently unclear whether this group of dogs could profit from more invasive surgery, as described under MCD, aiming to change the weight bearing axis.
Advantages of arthroscopy (4) over surgery?
Minimally invasive
Reduced morbidity (low infection rate)
Treatment of multiple joints in a single session
Improved visualisation of intra-articular structures