SA Joint Dx and OA Flashcards
What is the difference between primary and secondary arthritis?
Primary arthritis has no underlying aetiology - it is more rare
Secondary arthritis is much more common and occurs usually due to some form of damage to the joint
Is primary or secondary arthritis more common?
Secondary more common
What are you likely to see in the animals history when they ahve arthritis?
Stiffness particularly on rising - watch the dog as they come into the consult room
Worse after exercise
Waxes and wanes
Shifting lameness? Could suggest autoimmune dx
Worse in colder weather?
Exposure to ticks - lyme dx can potentially cause lameness
Bleeding tendency? Blood in the joint is very painful
What are you likely to see on a physical exam in an animal with arthritis?
- Lame
- Pain on manipulation
- Swelling to joints
- Associate muscle atrophy
- Neurological deficits?
- Systemic signs?
- Always compre with opposite limb
How can you make a provisional diagnosis for arthritis?
- If lameness mild - not unreasonable to trial therapy e.g. rest and analgesia
- If failts to respond after 1 - 2 weeks, a definitive dagnosis should be sought after
- Always try to get the owner to come back/make contact with the owner to find out if its worked or not
How can you confirm the diagnosis of arthritis?
Confirming the diagnosis
- further manipulation of joints ± sedation or GA: standard and joint specific (e.g. cranial draw, Ortolani)
- diagnostic imaging: radiography ( ± contrast), ultrasound, EMG, CT, MRI, scintigraphy
- arthrocentesis
- intra-articular or regional blocks (rarely performed in small animals)
- arthroscopy
- exploratory arthrotomy
What is ortolani a sign of?
Hip dysplasia
How should you perform radiography when trying to diagnose arthritis?
- Good quality: positioning, exposure and development
- Standard orthogonal views +/- stress views
- Radiograph opposite side for comparison if unsure
- Read filsm methodically
WHat is one of the first things you will see with an unhappy joint?
Joint effusion
Comment on these 2 radiographs
Left - normal
Arthritis joint on the right - can see new bone on distal end of patellar and some sclerosis
Area of whiteness within joint on right - joint effusions
What is demonstrated in these radiographs? What is it used for?
Which joint is it often used in?
Contrast arthrogram - a series of images of a joint after injection of a contrast medium
The canine shoulder is the only joint routinely assessed with positive contrast arthrography
What is ultrasound useful for with regards to arthritis?
Good for peri-articular soft tissue structures e.g. bicipital tendon
Can be used for detection of meniscal tears but requires a very skilled operator
What is arthrocentesis?
Arthrocentesis is a diagnostic test that is performed to determine the cause of joint swelling or arthritis, including septic bursitis, gout, or rheumatoid arthritis. Also known as joint aspiration, the procedure uses a sterile needle and syringe to drain fluid from a joint for further examination.
With arthrocentesis, when are you likely to just look at a single joint and when are you most likely to look at multiple joints?
Single joint likely to be septic or traumatic
Multiple joints (at least 3) for detection of polyarthritis
Where do you collect the artocentesis sample into?
Done by aseptic technique
Collection into plain, EDTA and blood culture medium if likely to be infected
Smears for cytology as well as count from EDTA sample
When doing a synovial fluid analysis, what should you look for?
Gross appearance
Viscosity (string test)
Protein content and mucin test
Cytology
What is normal synovial fluid like?
Honey coloured
Like syrup
Relatively clear
Good viscosity
With synovial fluid cytology, what is likely with small numbers of foamy macrophages?
Suggestive of degeneratiev disease
With synovial fluid cytology, what is likely with large numbers of neutrophils?
Large numbers of neutrophils in both sepsis and polyarthritis
Have a look at this table about synovial fluid analysis with regards to normal joint, degenerative joint disease, immune mediated arthritis and bacterial infective arthritis
What is a fragmented coronoid process most common in?
Most common in elbow dysplasia
What is arthroscopy?
What are some pros and cons?
Diadvantages:
- Difficult to do
Advantages:
- Joint morbidity reduced
- Magnification
- Therapeutic as well as diagnosti
What is this arthroscopy of?
Fragmented coronoid process - damaged articular cartilage
How can arthrotomy be useful for diagnostic?
Visualisation of pathology
Synovial biopsy
What is this, from arthrotomy?
Bucket handle tear assocaited with cruciate disease
What is a bucket handle tear associated with?
Associated with cruciate disease
What are some high return, relatively low cost tests when investigating joint disease?
Radiographs
Synovial fluid analysis
What are some predispositions to OA?
Genetics
Age
Systemic factors e.g. obesity
What are some joint biomechanics that can cause OA?
Injury
Developmental abnormality
Instability
Overload
What is pathophysiology of OA?
Fibrillation of articular cartilage of WEIGHT BEARING areas leads to fissuring leads to ulceration
There are microfractures that lead to stiffening of subchondral bone which leads to abnormal loading
Joint remodelling due to osteophyte development
What causes pain during OA?
Synovitis
Exposure of subchondral bone
What are some radiographic signs of OA?
- Joint effusion
- Osteophyte formation and bone remodelling e.g. patella
- Joint sclerosis
- Muscle atrophy
What is the cycle of presentation of OA in young animals?
Primary disease –> pain, instability
OA initiated –> pain, lameness, restriction of movement
Muscular growth provides support –> stabilisation and limitations of signs
What is the cycle of presentation of OA in adult animals?
Signs can be intermittent and vary in severity
Chronic atate +/- acute flare ups
Stiffness
Restriction of movement
Pain and lameness
Which muscles are important in preventing hip dysplasia if the animal is predisposed to HD?
Gluteal muscles
What are clinical signs of OA?
Clinical effects depend to some extent on the affected joint
- Worse in small ‘tight’ joints such as tarsus or elbow, comapred to large padded joints such as stifle or hip
- Worse in high motion joints such as antebracheocarpal joint vs low motion joints e.g. carpometacarpal
Which joints is OA worse in?
Worse in small ‘tight’ joints such as tarsus or elbow, comapred to large padded joints such as stifle or hip.
Tarsus and elbow worst - particularly tarsus as small joint and surface area and same weight on it as the hip! So tend to get greater changes on the smaller joints
How can you investigate OA?
Radiography (plain +/- contrast)
Arthrocentesis
Advanced imaging - CT or MRI
Arthroscopy
Synovial biopsy
Serology
What radiographic features do you see with OA?
- Soft tissue swelling
- Joint effusion
- Osteophytes
- Enthesiophytes
- Sub-chondral sclerosis
- Sub-chondral cyst
- Intra-articular mineralisation
What is the objectives of treatment of OA?
Control pain
Achieve an acceptable level of exercise
Limite the progression of the disease
What is the multi-modla approach to the treatment of OA?
Weight control
Exercise modification +/- physio
Analgesia
Neutraceuticals/ structure-modifying drugs
Treatments in development
Salvage procedures
What is the genreal therapeutic strategy for the treatment of OA?
- Weight control
- maintenance
- stick to appropriate exercise regime and bodyweight
- (strategic analgesia?)
- control ‘ flare-ups ’
- initial analgesia (7-10 days)
- rest e.g. 5 min. walks 3x day on lead
- gradual re-introduction of exercise
- ± physiotherapy / hydrotherapy
How can you control acute flare ups of OA with NSAIDs?
7-10 days of NSAID for acute flare up
What are some drug treatments for OA?
- Non-steroidal anti-inflammatories –mainstay
- Usually reserve corticosteroids for severe, non-responsive or end-stage cases
- NEVER combine CCS with NSAID ’ s
- Remember that all NSAIDs may have side-effects
- Switch from high to low dose rates
- Switch drugs if response is poor
- Pentasonpolysulphate(Cartrophen). Disease modifying compound. Studies inconclusive
- Try ‘ nutraceuticals ’ if response is poor
What are neutraceuticals and how can they be useful for OA?
- This is an area where evidence for use in small animals is lacking
- Off the shelf preparations may vary in their bioavailability when compared to veterinary designated products
- Chondroitin sulphate and glucosamine have been used in man to some benefit
- Glucosamine has mild anti-inflammatory action as well as an effect on chondrocyte metabolism
- Essential fatty acids maybe beneficial
- Also consider turmeric and green lip mussel
What are some research developments with regards to the treatment of OA?
Research developments
- Micropicking
- perforation of sub-chondral bone plate
- Joint resurfacing
- full thickness defects
- fibrin plugs and other biodegradable scaffolds
- Platelet rich plasma
- variable results
- Stem cell therapy
- harvest adipocytes and remove stem cells, grow on and inject into joint
- Gene therapy
When would you use micropicking?
If there is perforation of sub-chondral bone plate
When would you use joint resurfacing?
Full thickness defects
Fibrin plugs and other biodegradable scaffolds
What would you see with feline OA?
More difficult to detect
Discuss reduced activity levels and the ability to jump with the owners
General demeanour
Ability to groom
Over lamness is a rare sign
Give 2 examples of salvage procedures
Hip replacement with cemented stem
Fuse joint
