Elbow - Duerr Flashcards
Joint with WB fxn
Humeroradial
Joint that restricts motion to sagittal plane
Humeroulnar
Joint responsible for transverse plane pronation/rotation
Proximal radioulnar
This articulates with the radial head
Capitulum (Lateral)
This articulates with the medial portion of ulnar coronoid process
Trachlead (medial)
Coronoid disease
FCP or MCD - this is the most common in dogs! 99% of dogs that we see with severe OA of elbow is due to MCD
Ununited Anconeal Process
UAP
Osteochondrosis dissecans
OCD
FCP - how do we dx?
Rads, CT, scope
UAP - how do we dx?
Rads
Incongruity - how do we dx?
CT, scope
OCD - how do we dx?
CT
What can we do on PE to test elbow instability?
Full flexion, hyperextension, Campbell Test (carpus and elbow held at 90 degrees and then you sup/pronate)
Incongruity plays an important role in ___/___.
FCP/UAP
What is incongruity? What 3 places does it occur?
The joint surfaces “don’t match”
- Humeroulnar –> Notch incongruity
- Proximal radioulnar –> Step
- Humeroradial
What does a short radius do?
Puts pressure on coronoid process
FCP
Radioulnar incongruency
What does a short ulna do?
Puts pressure on anconeal process
UAP
Radioulnar incongruency
What kind of incongruity would cause FCP and UAP?
Trochlear notch incongruity (small notch)
Pressure on both coronoid and anconeal process
How do we correct UAP?
Ulna OsteOtomy - triceps pull restores elbow congruity by pulling the ulna proximally
Cut bone
How do we correct FCP?
Ulna OsteCtomy - allows shortening of ulna
Remove bone
What is MCD?
Medial compartment dz - aka FCP (old name)
Whats the pathogenesis of Coronoid Disease?
Unknown
There is a genetic component that has been proven
Incongruity can be a factor
Very diverse disease
Signalment: large breed dogs (labs, GSD, Rotties, Goldens, etc). Usually 6-18 months
Hx: variable lameness that is worse after exercise, stiff gait after rising, “lazy” but will still play, often bilateral so its hard to notice
PE:
- abnormal stance
- pain on palpation (hyperflexion, extension and medial compartment pressure/palpation)
- crepitus, reduced ROM & swelling in older, arthritic patients
Coronoid Dz!
What do you look for on rads of pt with suspected MCD?
- discontinuity of the coronoid process
- osteophytes on anconeal process and cranial aspect of the proximal portion of the radial head
- ulnar sclerosis
- A/P view –> can see fragment sometimes
Tx of MCD - Arthroscopy
- arthroscopic debridement
- ulnar ostectomy for incongruity
Are we “fixing” the problem of MCD with Arthroscopy?
NO! We are just slowing the progression… O’s need to know this and understand there is long-term OA management ahead of them
Prognosis of congenital FCP (MCD) in young dog?
Depends on severity of DJD
- Sx rec to slow down arthritis progression and dec lameness
- this is NOT a cure!
How does the congenital form and adult-onset form of Coronoid dz differ?
Congenital: (Common!)
- puppy with severe ED but little DJD -> may need CT for dx
- adult dog with moderate ED but severe DJD -> rads are adequate for dx
Adult-Onset form - rare!
- any mid-older aged dog with minimal rad changes
- traumatic in origin?
- congenital but not clinically?
- need CT or arthroscopy for dx
FCP - Summary
You need to ID early! ‘Normal’ rads ___ ___ R/O ED. Good PE and ideally CT esp for adult-onset. _____ ____ needed regardless of tx! Tx options vary but include fragment excision. Advise O about the severity of dz and lack of ______ procedures
do NOT
Medical Management
Salvage
How do we Tx Humeral OCD? Whats the prognosis?
Tx:
- excision of cartilage flap
- curettage and microfracture/-picking of the subchondral bone
- OATS
Prognosis:
- DJD is inevitable
- Medical OA management longterm
Define UAP
Anconeal process that doesn’t unite by week 20
Signalment of UAP pts:
Young, large/giant breed dogs (GSD< berners)
Males:Females 2:1
20-35% are bilateral
Pathogenesis of UAP?
Nutrition, genetic, trauma, OCD?
Incongruity (ED) - short ulna
Incongruity (traumatic)
- premature closure of distal ulnar physis
Concomitant dz –> FCP 15%
UAP - PE and Dx
PE:
- mild-moderate lameness
- pain on hyperextension
- joint effusion
Rads:
- do a flexed view –> this eliminates superimposition of the humerus
CT/Arthroscopy:
- evaluate for FCP and incongruity
All dogs with ED will become ___
Arthritic!
Do everything to preserve the joint!
Elbow injuries are best diagnosed with ____ particularly in young animals, however, when the animal is older ____ are usually sufficient since you should see _____. That is unless you are dealing with ______.
The prognosis for ED is ____ and hence the vet should focus on _____ OA management.
____ is easily diagnosed with ____ after _____, however, it can occur together with ____ which is why a _____ is preferred
CT
Rads
OA
Adult-onset
Poor
Long-term
UAP
Rads
20wks
FCP
CT
You have a dog with severe elbow OA –> on rads you do not see UAP (lucent line) –> what would you think they have?
MCD!! Most common
*OCD is rare
