Elbow dysplasia and osteochondrosis Flashcards
Osteochondrosis
Occurs as a result of focal failure of endochondral ossification or abnormal differentiation of cartilage into bone
The result is a thickened area of cartilage in either the epiphysis or metaphysis.
In the epiphysis this cartilage may fissure and partially detach from the underlying subchondral bone resulting in the typical ‘dissecting’ flap seen in osteochondritis dissecans.
Aetiology of osteochondrosis
a hereditary factor in the development of osteochondrosis but it is likely that the condition is multifactorial.
Dietary factors clearly identified as increasing risk for juvenile bone and joint diseases are high calories, high absolute calcium and ad libitum feeding.
Owners should be advised NOT to breed from affected animals, their siblings or parents
Signalment of osteochondrosis
Commonly occurs in the shoulders, elbows, stifles, and hocks of immature large-breed and giant-breed dogs.
Onset of signs is between 4 months and 10 months of age.
Usually large or giant breeds such as the Labrador retriever, Rottweiler, Bernese mountain dog, Great Dane. The Border Collie is also often affected.
Males are generally affected more commonly than females
Clinical signs of oesteochondrosis
Lameness is often insidious in onset, chronic and deteriorates after rest or excessive exercise.
The condition is commonly bilateral.
Affected joints often have a reduced range of motion (ROM) and pain can be elicited by attempts to fully extend (or flex) the joint, there may be joint thickening or effusions.
In bouncy puppies physical examination findings may be subtle such as only slight withdrawal of the elbow on attempts at full flexion or extension - if in doubt proceed to radiography
Radiorgaphy of osteochondrosis
Changes are fairly specific for each joint but include areas of thickened cartilage (seen as subchondral bone defects), mineralised OCD flaps or joint mice, osteocartilaginous fragments and peripheral osteophyte formation.
In the early stages of the disease signs can be subtle so if the index of suspicion is still high it can be useful to repeat radiography in 4-6 weeks.
Therapy for osteochondrosis
Varies dependent on the joint involved and severity of the disease.
Generally in the larger joints such as the shoulder and stifle the thickened flap of cartilage is removed.
The subchondral bone defect may heal with fibrocartilage but this may be influenced by size of lesion, weight bearing and age.
How can healing be improved after therapy for osteochondrosis
Forage - drilling small holes in the subchondral bone to allow the influx of blood vessels….healing by fibrocartilage formation
Joint resurfacing: Osteochondral autograft or allograft (complications) vs Joint resurfacing implants
Regenerative medicine
Chondrectomy - ensure all under run cartilage is removed and margins of defect are vertical
the use of polysulphated glycosaminoglycans or hyaluronic acid may be beneficial
early controlled weight bearing encourages healing – e.g. 4-6 weeks of lead only exercise
Prognosis of osteochondrosis
This varies on the joint affected.
After surgery for shoulder OCD the prognosis is very good, however the prognosis for a full return to function for hock and elbow osteochondrosis is much less likely.
Site of osteochondrosis in the shoulder
Caudal humeral head
Site of osteochondrosis in the elbow
Medial humeral condyle
Site of osteochondrosis in the carpus
Retained cartilaginous sores - distal ulna
Site of osteochondrosis in the stifle
Lateral (or medial) condyle - femur
Site of osteochondrosis in the hock
Medial (or lateral) talar ridge - talus
Signalment of shoulder osteochondrosis
Giant breeds and Border Collie
Age at onset - 4-8months
Sex - females more commonly affected than males
Clinical signs of shoulder osteochondrosis
uni or bilateral forelimb lameness,
shoulder muscle atrophy
pain on shoulder extension
Radiography of shoulder osteochondrosis
mediolateral view of both shoulders (supinated or pronated views rarely indicated)
subchondral defect with flattening of caudal humeral head
mineralised cartilage flap
mineralised joint mouse
DJD - osteophyte formation on caudal glenoid and humeral head
Treatment of shoulder osteochondrosis
Conservative - with small lesions and detached lesions then conservative treatment consisting of 4 weeks rest and NSAIDs as necessary may be successful.
Surgery - surgical debridement of detached flap or joint mice in bicipital groove
Surgical approach to shoulder osteochondrosis
the caudal approach gives adequate exposure with minimal trauma.
- Incise from mid scapular spine to the proximal humerus
- Dissect through subcutaneous fascia and fat and between the scapular part of the deltoid and the long and lateral heads of the triceps
- Reflect the caudal circumflex humeral artery and vein and the brachial nerve with 2 pairs of blunt gelpi retractors
- Identify the caudal glenoid and humeral head by palpation and manipulation of the shoulder and incise through the joint capsule in a DV direction
- Use a Hohman retractor and strong internal rotation of the joint to expose the OCD lesion
Prognosis of surgery for shoulder osteochondrosis
90% of dogs will respond favourably to surgical debridement with alleviation of lameness
Post operative management for shoulder osteochondrosis
strict rest / short lead walks for four weeks
Complications of surgery for shoulder osteochondrosis
failure to remove the whole flap especially medially,
seroma formation (10%)
Stifle osteochondrosis
Of the four joints most commonly affected with osteochondrosis the stifle is the least commonly affected.
The lesion is usually seen on the lateral condyle.
Signalment of stifle osteochondrosis
giant breeds most commonly affected.
Present between age 4 – 10mths.
Males and females both affected.
Presenting sign with stifle osteochondrosis
hind limb lameness chronic
Physical examination of stifle osteochondrosis
stifle effusion and pain on full extension and flexion.
May be concurrent problems such as cranial cruciate rupture or patella luxation
Investigations – radiography, mediolateral and craniocaudal views.
Flattening of the medial aspect of the lateral condyle with sclerosis of the underlying bone may be seen on both views but the craniocaudal view is more useful.
Investigations of stifle osteochondrosis
radiography, mediolateral and craniocaudal views.
Flattening of the medial aspect of the lateral condyle with sclerosis of the underlying bone may be seen on both views but the craniocaudal view is more useful.
Treatment options for stifle osteochondrosis
may be detected as an incidental finding when other stifle problems are present e.g. in an older dog with CCL disease.
In cases where there is obvious lameness, effusion and pain present then an arthrotomy and debridement of loose cartilage flaps may be beneficial.
Alternatively a techique of bone grafting can be performed (OATS) whereby a block of bone capped cartilage is taken from a non weight bearing region of the knee and placed in the area of bone affected by OCD.
Post operative care for stifle osteochondrosis
restricted exercise for 4 weeks after surgery.
Breeding from affected animals is not recommended
Hock osteochondrosis
The hock joint is less commonly affected by osteochondrosis than the elbow or shoulder joint.
Because of this less is known about the prognosis, and guidelines on management are less well defined.
The lesions are most commonly seen on the medial talar ridge and much less frequently on the lateral talar ridge.
Signalment of hock osteochondrosis
Rottweillers, Mastiffs, Labradors and Bull Terriers
Males and females affected.
Possibly males over represented
Animals present from 5mths to a year of age
History of hock osteochondrosis
Chronic lameness
Gait evaluation of hock osteochondrosis
affected animals have a very upright stance to their hocks to the extent of almost being hyperextended
Physical examination of hock osteochondrosis
there will be a reduction in flexion of the hock, with crepitus and pain on manipulation.
A palpable effusion or thickening is usually present
Investigations of hock osteochondrosis
Radiography - mediolateral and dorsoplantar views are usually sufficient to show the lesion.
Other views that may be useful include those that skyline the talar ridges such as the flexed dorsoplantar view, or oblique views if lateral lesions are suspected.
Changes seen on radiographs include all or some of the following: flattening of the medial talar ridge, an increase in joint space, mineralised flaps, osteophytes and peri-articular swelling.
Treatment options for hock osteochondrosis
similar to elbow OC decisions as to whether to treat the condition surgically or conservatively should be made after consideration of a variety of factors.
If the animal is obviously lame, painful, with minimal arthritis or if there is an obvious flap then surgery may be indicated.
If the lesion is small, lameness is minimal or absent or there is well established osteoarthritis then conservative treatment may be more suitable.
Conservative mangement of hock osteochondrosis
minimal lead only exercise for 4 weeks.
NSAIDs for the first two weeks.
Then make a gradual return to normal exercise.
Surgical management of hock osteochondrosis
An approach to the tibiotarsal joint is made by an incision through the joint capsule caudal to the medial collateral ligament.
By flexing and extending the joint intra operatively most of the caudal 50% of the medial talar ridge can be accessed.
Loose flaps of cartilage are debrided and the joint flushed.
Post operative management for hock osteochondrosis
Post operatively animals should be managed with rest similar to the conservative management described above.
Bandaging for ten days post op may also be beneficial – reducing pain and swelling.
Prognosis of hock osteochondrosis
guarded.
Arthritis will develop and in very severe cases arthrodesis may be indicated.
Elbow dysplasia
An abnormal development of the elbow joint that occurs in dogs during the growth phase.
Consequence of elbow dysplasia
joint incongruity causing a variety of different problems (more than one of these problems may occur in the same elbow joint at the same time):
- Fragmented medial coronoid process ( FMCP)
- Osteochondritis dissecans (OCD) of humeral condyle
- Un-united anconeal process (UAP)
- Joint (radio-ulnar) incongruity
Signalment of elbow dysplasia
Large and giant breeds
Smaller chondrodystrophic breeds
Bilateral disease 25-80%
Males 2x more common
6-12 months of age (older dogs also diagnosed with ED)
Aetiology of elbow dysplasia
Multifactorial
Clear genetic association
As with hip dysplasia, elbow dysplasia is a polygenetic trait with both hereditary and environmental components
Elbow screening represents an attempt to limit ED through selective breeding
Clinical signs of elbow dysplasia
Lameness
Often shortened (‘choppy’) FL gait
Commonly bilateral, often asymmetric
Effusion (best detected on the lateral aspect of the joint between the lateral epicondyle and olecranon)
Pain +/- crepitus, reduced ROM
Coronoid Disease/Medial fragmented coronoid process (mFCPD)
most common problem associated with elbow dysplasia
Labradors, GSDs, BMDs
6-14 months
Medial coronoid fragments due to sub-surface fissuring
Hard to see on X-ray - CT preferred
Arthroscopy is definitive
Untreated, will lead to DJD…but benefits of surgery not clear
Osteochondrosis and Osteochondritis dissecans (OCD) of the medial humeral condyle
Usually the subchondral bone located immediately underneath the damaged area of cartilage is also affected.
Medial humeral condyle
Failure of endochondral ossification
Subsurface failure and cartilage lifts
Inflammation, pain, DJD
Surgical management - arthroscopic debridement +/- osteoarticular graft
Ununited anconeal process (UAP)
anconeal process fails to fuse with the main ulna bone during the growth phase - normally would fuse by 5 months
Breeds commonly affected are German Shepard dogs, Great Danes, Basset Hound
Usually diagnosed based on radiographs, but the other conditions (FCP, OCD, and MCD) often cannot be distinguished
Surgery offers best prognosis
○ Reattachment if possible
○ Fragment removal if not
Diagnosis of elbow dysplasia
Case history
Forelimb lameness that worsens after exercise
Acute or chronic.
Owners frequently complain that the dog is stiff in the morning or after rest.
There may be a coincidental history of trauma
Clinical presentation/signs of elbow dysplasia
may show lameness of one or both front legs that worsens after exercise, stiffness and reluctance to exercise.
Often they stand with the front feet turned away from the body and the elbows tucked in.
Clinical signs generally start showing between 5 and 7 months
Clinical examination of elbow dysplasia
Orthopaedic examination reveals pain at manipulation of the elbow and swelling of the joint is usually palpable.
Palpation is generally non-painful but manipulation through a full ROM shows reduced flexion and often pain on full extension or flexion of the joint.
In cases affected by severe osteoarthritis, a restricted range of movement of the joint is also generally noted.
Radiography of elbow dysplasia
in very early cases no changes will be identified - repeat in 4-6 weeks if still showing signs
earliest sign - new bone on dorsal anconeal process (see on FLEXED mediolateral radiograph)
later arthritic changes seen on radial head, medial ulna and medial epicondyle of humerus
in some cases may see the lesion rather than just arthritic change e.g.:-
* flattening of medial humeral condyle on craniocaudal view if OC
* fragmentation/poor distinction of medial coronoid process of ulna in FCP
* Also subtrochlear sclerosis
ununited anconeal process usually obvious in dogs > 5mths
CT of elbow dysplasia
Most reliable non surgical test
Can diagnose incomplete fragmentatio of the medial coronoid process
Arthroscopy of elbow dysplasia
enables treatment via minimally invasive surgery to be performed at the same time if indicated
advantage of enabling direct visualisation of the cartilage surface
Usually used with CT
Treatment of elbow dysplasia
Conservative - weight loss and exercise restriction
Rehabilitation - shockwave, laser, PRP
Nutraceuticals and chondroprotectants
NSAIDs
Surgery - quite controversial
Coronoid disease
Medial fragmented coronoid process (mFCP)
Treatment can be conservative or surgical.
Coronoid disease will lead to osteoarthritis in all cases.
Conservative treatment of coronoid disease (CD)
weight control,
exercise management,
hydrotherapy and physiotherapy,
nutraceuticals (joint supplements)
painkillers.
Surgery for coronoid disease
arthroscopic removal of the fragments is generally performed and this leads to an improvement of the clinical signs in about 2 dogs out of 3.
Subtotal coronoidectomy.
Surgery not clearly better than conservative care.
Treatment of osteochondrosis and osteochondritis dissecans
arthroscopic removal of the cartilage flap and possibly placement of a osteochondral graft.
This doesn’t improve clinical signs in a few cases.
Osteostyxis for osteochondrosis
Hammer it
Bleeds and forms a clot
Clot turns into fibrocartilage
Works for small lesions but not large lesions
Osteochondral transplant for elbow dysplasia
Osteochondral plug
Hit into subchondral bone
Fractures the base of that to create free piece of bone
Core out lesion
Put new cartilage back into hole
Natural auto-transplant
Elbow joint replacement for elbow dysplasia
Replace whole articulation
Over time they start to loosen
Elbow arthrodesis for elbow dysplasia
Plate holds the elbow stationary
End stage elbow disease
Primary goal is pain relief
Function can be quite variable
Alternative to amputation
Elbow incongruity
Step between the radius and ulna
Short radius > short ulna
Hard to diagnose on x-ray, CT better
Surgical management usually involves ulnar osteotomy to allow the ulna to ‘find a new position’
Treatment of ununited anconeal process (UAP)
In young dogs (under 8 months of age) can be reattached to the ulna with a screw
To stimulate fusion and counteract the abnormal forces acting on this bony process, an ulna osteotomy or ostectomy is generally also mae
Older dogs can be treated with conservative management or removal of the anconeal process
Osteoarthritis in elbow dysplasia
A consequence of all cases of elbow dysplasia
weight management and exercise modification are the best ways to influence outcome
Prognosis of elbow dysplasia
no curative treatment
prognosis is guarded for dogs in regards to the development of osteoarthritis.
However, clinical improvement is seen in many cases after the various treatment options, and many dogs with elbow dysplasia can still have an excellent or good quality of life.
A small group of patients, however, may not respond to any treatment and for those salvage procedures, like a total elbow replacement, may be considered.
