Tendons, ligaments + muscles

Question 1

What do tendons do?

Answer 1

*Transfer force generated by muscle to bony attachments
*Support joints
*Store energy

Question 2

What do ligaments do?

Answer 2

*Attach / stabilise bones/joints
*Protect tendons
*Proprioception

Question 3

What type of collagen are tendons?

Answer 3

*95% collagen type I
*1-5% type III

Question 4

What type of collagen are ligaments?

Answer 4

*90% collagen type I
*10% type III

Question 5

What type of injuries can occur to tendons/ligaments?

Answer 5

*Extrinsic - external trauma (laceration)
*Intrinsic - overload / degenerative
*Intrasynovial / extrasynovial
*Extensor vs Flexor tendon

Question 6

How are tendon / ligament injuries diagnosed?

Answer 6

*History - age, type, previous injury, recent exercise, wound / laceration
*Clinical exam - stance / gait, palpation
*Diagnostic imaging - ultrasound, radiography, MRI

Question 7

What should be assessed with ultrasound in tendon / ligament disorders?

Answer 7

*Change in cross sectional area
*Fibre echogenicity
*Margination
*Position - rupture
*Focal lesion vs generalised changes
*Acute vs chronic changes
*Blood flow to assess neovascularisation

Question 8

What are the clinical signs of acute inflammatory phase of tendon / ligament injury?

Answer 8

*Lameness
*Pain on palpation
*Heat
*Swelling

Question 9

What is the pathology of acute inflammatory phase of tendon / ligament injury?

Answer 9

*Haemorrhage
*Inflammation
-neutrophils
-macrophages + monocytes
-oedema
-proteolytic enzymes

Question 10

What are the treatment principles of acute inflammatory phase of tendon / ligament injury?

Answer 10

*Limit inflammation - cold therapy / NSAIDs
*Protect limb / reduce further damage - supporting bandage / rest

Question 11

What are the clinical signs of proliferative phase of tendon / ligament injury?

Answer 11

*Reduction / absence of lameness
*Resolution of signs of inflammation
*Tendon still palpably enlarged
*signs of re-injury if exercised too early

Question 12

What is the pathology of proliferative phase of tendon / ligament injury?

Answer 12

*Angiogenesis
*Fibroplasia

Question 13

What are the treatment principles of proliferative phase of tendon / ligament injury?

Answer 13

*Promote angiogenesis
*Minimise formation of excessive scar tissue
*Early exercise if lesion filled in

Question 14

What are the clinical signs of tissue modelling phase of tendon / ligament injury?

Answer 14

*Stiffer / thicker tendon

Question 15

What is the pathology of tissue modelling phase of tendon / ligament injury?

Answer 15

*Fibrosis
*Gradual change from collagen III to I

Question 16

What are the treatment principles of tissue modelling phase of tendon / ligament injury?

Answer 16

*increased loading + exercise programme
*Improve fitness
*Monitor progress by repeat ultrasound exam

Question 17

What is an example of a laceration injury + how would you treat it?

Answer 17

*Flexor tendon laceration
*Repair ends if feasible
*Cast

Question 18

What is an example of an avulsion fracture + how would you treat it?

Answer 18

*Collateral ligament avulsion
*Re-attach avulsed bone fragment
*Arthrodese joint
*Cast

Question 19

What is an example of an intra-synovial tendon / ligament tear + How would you treat it?

Answer 19

*SDFT tear in digital flexor tendon (horse)
*Debride torn tendon / ligament fibres

Question 20

What is an example of a joint instability + How would you treat it?

Answer 20

*Cruciate rupture in stifle (dogs)
*TPLO

Question 21

What are skeletal, smooth muscle and cardiac myopathies?

Answer 21

*Skeletal = weakness / spasm
*SMooth = retention / incontinence, hypermotility / stasis
*Cardiac = circulatory failure

Question 22

How are muscle conditions diagnosed?

Answer 22

*History
*Clinical exam - acute / chronic
*Biochemistry
*Ultrasound - acute = haematoma, chronic = fibrosis / calcification
*Muscle biopsy

Question 23

What are general reactions of muscle?

Answer 23

• Atrophy
• Hypertrophy
• Degeneration
• Regeneration and repair
• Calcification and ossification
• Pigmentation
• Circulatory disturbances

Question 24

What can cause atrophy of muscle?

Answer 24

*Disuse - reversible
*Denervation - irreversible
-Trauma / myaesthenia gravis

Question 25

What causes hypertrophy?

Answer 25

*increased workload *Compensatory hypertrophy

Question 26

What are the 3 different types of degeneration?

Answer 26

*Cellular swelling *Hyaline degeneration *Granular degeneration

Question 27

When does regeneration + repair occur? What happens if it can't regenerate?

Answer 27

*Regeneration + repair is less severe degeneration = back to normal function *If irreversibly damaged tissue = Calcification + ossification

Question 28

What can blockage of main arteries + veins cause in cats, horses + cattle?

Answer 28

Distal aorta / iliacs =Aortic-iliac thrombosis in horse =Saddle thromi in cats w left sided cardiomyopathies Venous =blockage of large veins = congestion w leakage to muscles = muscle necrosis + fibrosis *Occurs in prolonged recumbent large animals

Question 29

What causes white muscle disease?

Answer 29

*Selenium / vitamin E deficiency in calves

Question 30

What are the clinical signs of white muscle disease?

Answer 30

*Muscle weakness / stiffness, recumbency, dyspnoea *Arrythmias if myocardium affected *Myoglobinuria

Question 31

How is white muscle disease treated?

Answer 31

*Parenteral administration of selenium / vitamin E

Question 32

How does stiff lamb disease present?

Answer 32

*Neck + tongue muscle stiffness / weakness in young lambs *Shoulder, thigh, back + intercostal muscle stiffness / weakness in older lambs *More pronounced calcification than white muscle disease in calves

Question 33

How is stiff lamb disease treated?

Answer 33

Vitamin E / selenium supplementation

Question 34

What are the signs of acute exercise induced exertional rhabdomyolysis in horses?

Answer 34

*Unfit horse (colic signs) *Stiffness to severe pain / recumbency *Commonly gluteals, semitendinosus, semimembranosus affected

Question 35

How is acute exercise induced rhabdomyolysis in the horse diagnosed + treated?

Answer 35

Dx = clinical exam, muscle enzymes + myoglobinuria Tx = Pain relief, fluid therapy, acepromazine

Question 36

How is chronic exercise induced exertional rhabdomyolysis treated?

Answer 36

*Warm up *Avoid stress + high energy feeds

Question 37

What causes polysaccharide storage myopathy? How is it diagnosed + treated?

Answer 37

*Cause = accumulation of glycogen *Dx = semimembranosus muscle biopsy *Tx = diet (low carb / high fibre), oil to replace carbs for energy

Question 38

What animals does eosinophilic myositis affect? What are the clinical signs?

Answer 38

*Large breed dogs - GSD *Acute recurrent pain + mandibular immobility *Bilaterally enlarged temporal / masticatory muscles

Question 39

How is eosinophilic myositis treated?

Answer 39

Corticosteroids

Question 40

What are some bacterial conditions affecting muscles?

Answer 40

*Blackleg *Malignant oedema

Question 41

What are some parasitic conditions affecting muscles?

Answer 41

*Trichonellosis *Cysticercosis *Toxoplasmal myositis *Sarcocysts

Question 42

What are the signs of atypical myoglobinuria?

Answer 42

* Acute onset, rapid and frequently fatal * Muscle weakness/recumbency * Increased CK/AST and myoglobinuria *Post mortem = widespread myonecrosis (skeletal + cardiac)