26.5.2: Understanding soft tissue pathology Flashcards
How does soft tissue pathology lead to significant losses in racehorses that are in training?
- Loss of days in training - injured horses likely to be removed, reducing revenue for trainers
- Presentation to racecourses - reduces entry fees and racecourse finances
- Wastage - some horses removed from racing but continue in other disciplines, some PTS due to poor prognosis
Which tendons are most commonly injured in horses?
- In racehorses, most commonly forelimb and SDFT
- In event horses, most commonly SDFT, then suspensory ligament, then DDFT.
What are COMP and crimp and why are they important in tendons?
COMP: cartilage oligemtric matrix peptide -> correlated with elasticity of tendon. More COMP = more elastic.
Crimp: straightens out in the initial phase of tendon loading.
- Comp and crimp decrease with age
- Tendons have large amounts of ECM and relatively few cells (consider implications for healing and remodelling)
- Blood supply to tendons is poor especially within sheaths and bursae -> poor recruitment of inflammatory cells, especially when needed in the acute phase of injury
ECM: extracellular matrix
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Where do most SDFT injuries occur?
Where do most DDFT injuries occur?
Where do most suspensory ligament injuries occur?
Where do most ALDDFT injuries occur?
How would you assess a tendon for microdamage?
- Always scan both tendons. Compare CSA.
- Look for hypoechoic structures within the tendon
- SDFTs especially have poor ability to remodel and repair in the adult horse; they accumulate microdamage and then suddenly go wrong (like a stress fracture)
What are interference injuries and what can you do to reduce them?
- Interference injuries = when loaded forelimb struck by protacted hindlimb at speech; often skin lacerations seen
- Can wear boots so less likely to injure if struck
- However there is a physiological heating effect with wearing boots
What is the inflammatory phase of tendonopathy and when does it happen?
Inflammatory phase: occurs immediately after injury for several days.
The proteolytic enzymes from macrophages are part of cleanup but can make things worse.
Want to moderate this process as much as possible.
What is the proliferative phase of tendonpathy?
Occurs in weeks after injury as fibrosis happens.
What is the remodelling/ maturation phase of tendonpathy and what clinical signs and pathology will you see?
Occurs for months after injury.
* Collagen transformation happens slowly
* Will never get tendon back to what it was, but hopefully get close
* Top image: homogenous but not yet nice fibre pattern. Gradually becomes more linear.
