Multi-limb lameness

• Types of multi-limb lameness - generalised osteoarthritis

  Seen in older dogs. This usually arises in breeds which suffer from concurrent development disease such as elbow dysplasia, hip dysplasia or acquired disease e.g. cruciate rupture.
• Types of multi-limb lameness - panosteitis

  Inflammatory condition in multiple long bones. Most common in the young male (<2 years) GSD.
• Types of multi-limb lameness - septic arthritis

  In the younger animal this occurs in multiple joints. In the older animal a single joint is generally effected. It may occur following surgery or via Haematogenous spread.
• Types of multi-limb lameness - pulmonary osteopathy

  A paraneoplastic syndrome with Proliferative new bone on the limbs.
• Types of multi-limb lameness - metaphyseat osteopathy

  Inflammatory condiotn seen in young dogs. Assocaited with a space occupying lesion in the chest. Characteristic radiographic changes. Prognosis is good to fair.
• Types of multi-limb lameness - rickets

  Seen occasionally, associated mainly with a poor diet but can also be a lack of sunlight. Affects many limbs.
• Types of multi-limb lameness - nutritional hyperparathyroidism

  All meat diets in the young animal. Poorly mineralised bones with multiple folding fractures and collapse of vertebrae.
• Types of multi-limb lameness - Immune mediated arthritis

  This is the most common cause of multiple limb lameness. Most common cause. Inflammatory condition involving multiple joints.
• Multi-limb lameness - signalment and hisTory

  Age - young dogs are more prone to vaccine associated polyarthritis, panosteitis and viral casues such as calici virus in the cat.

  Breed predilections - SharPei fever

  Recent vaccination or drug administration - potentiated sulphonamides.

  Recent tick exposure

  Recently imported from abroad.

  A history of respiratory or GI disease.
• Types of multi-limb lameness - Clinical presentation

  Generalised lameness in multiple joints, sometimes a shifting lameness.

  May be worse in one limb, or if both bad animal may not appear lame but will have a short gait.

  Joints may be visibly or palpably swollen and painful on manipulation. There may be accompanying muscle pain.

  The animal may be systemically unwell (pyrexia).

  Could have a history of previous episides.
• Multi-limb lameness - radiography

  Variable in its helpfulness, most polyarthritic condition will not show radiographic changes.

  Radiography of other body systems such as lungs for pulmonary osteopathy and pulmonary adenocarcinoma in the cat.
• Multi-limb lameness - arthrocentesis

  Generally performed on the more distal joints as these are the more commonly affected joints.

  Tap at least 4 joints - carpus, tarsus, stifle and elbow.

  Joint fluid may be watery have a low viscosity and be obviously turbid. Normal gross appearance does not rule out the condition.

  Cytology for immune mediated disease shows WBC, predominantly neutrophils as would a septic arthritis or vector borne disease like Lyme disease.
• Multi-limb lameness - Appearance of synovial fluid

  Examine gross appearance:

  • Colour and gross appearance.
  • Viscosity - stringing?
  • Protein mucin clot time.
  • Cell count - large enough volume
  • Cell morphology - active foamy macrophages (degenerative joint disease), neutrophils (sepsis or multi joint polyarthritis).
• What are the erosive forms of immune-mediate polyarthritis?

  Rheumatoid arthritis

  Chronic feline erosive progressive polyarthritis
• What are the non-erosive forms of immune-mediate polyarthritis?

  Immune mediated polyarthritis

  Systemic lupus erythematosus

  Feline non-erosive chronic progresive polyarthritis

  Breed assocaited - Sharpei fever

  Drug and vaccine associated polyarthritis

  Polyarthrits/myositis and polyarthritis/meningitis syndrome
• Immune mediated polyarthritis - overview

  Should be considered in all Pyrexic cases when an obvious cause is not identified.

  Any synovial joint can be affected including the axial skeleton and Intra-articulate vertebrae.

  They can be divided into erosive and non-erosive
• Typing immune mediated non-erosive polyarthritis

  Type I - no underlying disease detected (idiopathic the most common form).

  Type II - associated with infection elsewhere e.g. respiratory or urinary tract infection. May spontaneously resolve with treatment fo the underlying condition or require immunosuppressant.

  Type III - associated with GI disease.

  Type IV— associated with neoplasia e.g. myeloproliferative disease
• Breed associated polyarthritis - Shar Pei fever

  Common (as many as one in four) and characteristic of the breed.

  Juvenile onset

  Pyrexia.

  Swollen hock joint (can be other joints( although swelling is primarily periarticular.

  Later development of renal amyloidosis and renal failure.
• Breed associated polyarthritis - juvenile onset polyarthritis of Japanese Akitas

  Less than one year of age.

  Poor prognosis.
• Rheumatoid arthritis — overview

  Severe and debilitating.

  Destructive with radiographic lucencies.

  Loss of articualr surfaces and collapse of joint space and subluxation of the joints.

  RF (rheumatoid factor - serological test) positive but this can occur with other diseases, will be a contributory factor when diagnosing RF.

  Synovial biopsies show typical changes, several diagnostic criteria need to he satisfied to make this diagnosis.

  Prognosis is poor and euthanasia is often required.

  
• Erosive feline chronic progressive polyarthritis- young male condition

  The erosive and non-erosive forms may be the same condition, can get new bone or the absence of new bone.

  A rare condition most common in the young male.

  A destructive polyarthritis, in both forms there is a marked proliferative reaction around the joints.

  Joint subluxations can accompany the disease, is an aggressive and debilitating condition which responds poorly to treatment.

  
• Treatment of immune mediated joint disease - immunosuppressive agents

  Prednisolone - the mainstay of treatment, side effects are common including polydipsia and hepatopathies.

  Azathioprine - used when prednisolone is ineffective. Not to be used in cats.

  Chlorambucil - can cause immunosuppression, can suppress myeloid.

  Methotrexate - used with leflunomide of rheumatoid arthritis in cats.

  Cliclosporin, cyclophosphamide, levamisole.
• Treatment of immune mediated joint disease - analgesia

  NSAID to be avoided if using corticosteroids

  Paracetamol (in the dog) and opiates.

  Bedinvetmab (librela) and Frunevetmab (Solensia) monoclonal antibody to the nerve growth factor.

  Weight reduction and hydrotherapy to maintain joint health.
• What are the clinical signs of myopathies?

  Muscle atrophy

  Reduced muscle tone and local reflexes.

  Dysphonia, dysphasia and regurgitation.

  Megaoesophagus - muscle fibres are not functioning anymore.

  Pyrexia in inflammatory myopathies

  Pain in the temporal muscles and a reluctance to open the mouth witch a masticatory muscle myosotis (eosinophillic temporal myositis) or, after a few weeks, marked muscle atrophy.
• What are the types of inflammatory myopathies?

  Masticatory muscle myositis (MMM)

  Immune mediated disease e.g. SLE

  Protozoal infections e.g. toxoplasma and neospora.
• What are the types of non-inflammatory myopathies?

  Genetic disorders e.g. Labrador myopathy (Floppy Labrador).

  Corticosteroids induced (Prednisolone) (endogenous and exogenous).

  Endocrine associated e.g. Cushings disease and hypothyroidism.

  Metabolic abnormalities e.g. phosphofructokinase deficiency in the Springer spaniel.
• Inflammatory and non-inflammatory myopathies - clinical exam

  Swollen and atrophied muscle. Can be hard to differentiate between muscle and joint pain as when you move the joints you also move the muscles.
• Diagnosing inflammatory and non-inflammatory myopathies - testing

  Blood samples including CPK, electrolytes, lactate and pyruvate.

  Thyroxine for hypothyroidism or MMM auto-antibodies serology for myasthenia gravis (a neuromuscular disease).
• Muscle biopsy

  These are taken from the quadriceps, biceps femoris or triceps.

  If suspect neuromuscular disease then cranial tibialis is a good muscle to biopsy.

  Careful tissue handling is essential.

  Samples are collected along the length of the fibres.

  Placed in 10% formalin for H&E staining and also a fresh sample can be sent wrapped in moist gauzes and cooled for freezing prior to electron microscopy.
• What is the treatment for inflammatory myopathies?

  Antibiotics for protozoal infections e.g. clindamycin

  Immunosuppresive doses of corticosteroids if autoimmune disease is suspected.
• How do you treat non-inflammatory myopthies?

  Breed associated genetic myopathies:

  • Diagnose with muscle biopsy
  • No treatment.

  Metabolic disorders:

  • Dietary modifications may help these conditions.

  Endocrine associated myopathies:

  • Treat the underlying condition.
• What is Myotonia?

  Increased tone and poor relaxation after muscle stimulation - if you press into the muscle and create a dimple, the dimple remain as the muscle does not relax afterwards.
• How do you treat myotonia?

  Procainamide mixelitine and phenytoin, to allow the relaxation of the muscle.