Equine soft tissue injuries of the distal limb Flashcards
What is strain
the amount a tendon elongates for amount of stress put into it
Curve not linear
Sections of stress strain graph
1 = straightening of tendon crimp, don’t get much deformation
2 = elasticc deformation; tendon absorbs lots of strain before deforming and returns elastic energy
3 = non-elastic deformation; potential for microdamage here
4 = failre/rupture
What safety factor do most equine soft tissues have
only 1.2
What is COMP
Cartilage oligometric matrix peptide
Involves in organising collagen into efficient systems; high early in life esp in middle of SDFT where it needs to be more elastic
What age is COMP high i.e window to make a difference with tendon education
<3 years
Difference in collagen in DDFT between mid metacarpal region and fetlock
In mid metacarpal region, more elastic with lots of type 1 collagen
In fetlock region, it is changing direction and needs to be resistant to compreeion; more type II colagen
What is chondroid metaplasia
Where there is more type II collagen in a tendon so it is more ike cartilage
See this where tendons change direction
Also after injury
What has suspensory ligament evolved from
interosseus muscle; so it has some muscle fibres and fat
Where do most SDFT injuries happen
Mid metacarpal region; mostly forelimb
Where do most DDFT injuries happen
Where it changes direction i.e around fetlock within tendon sheath or around navicular bone wihtin hoof
Where do suspensory ligament injuries tend to happen
At prox origin + insertion onto prox sesamoid bones
Where do check ligament injuries happen and how do they present
IN prox third of forelimb metacarpus on lateral side
Get a pathognomic lateral swelling
What are common soft tissues around stifle that get injured
Cruciate ligament
Medial meniscus
When does most tendon education happe
in the foal so want foal to be active
Why should we refrain from training horses at competition standard too often
Because this puts them in stage 3 of stress/strain graph i.e above threshold for microdamage of tendons
What are the advantages/disadvantages of overreach boots and when should we use them
can stop overreach injuries
But contributes to physiologcal heating effect in tendons so can cause denaturaiton
Only use in horses that tend to overreach
What happens in the remodelling phase o tendon injury
Tendon size decreases
Transformation back to springy type I collage from type III
Why do scar tissue lesions in tendons tend to extend proximally and distally over same cross sectinoal area
Because this section is non-compliant so during tendon stretch there is pulling on the parallel fibres above and below the lesion
What structures are within the digital flexor tendon sheath
DDFT
SDFT
MAnica flexoria
Palmar/plantar annular ligament