Tendonitis And Tendon Laceration Flashcards
Where does the SDF tendon insert?
Divides at P1 and inserts primarily on P2
Where does the DDF tendon insert?
P3
Where does the suspensory ligament originate and insert ?
Originates from proximal MC/MT III
Insert on seasamoid bones
Extensor branch of seasmoid ligament joints common digital extensor tendon
What is the purpose of the endotendon?
Provides intrinsic blood supply
Has nerves, growth factors, and provides elasticity
What is the epitenon ?
Contiguous with endotendon, surrounds tendon
What is the paratenon?
Surrounds tendons NOT in a sheath
Reduces frictional forces, supplies blood vessels, repair elements
What do you call the stain able to be exerted on a tendon that it goes from crip pattern to straight?
Toe region
The toe region (crimp to straight) allows the tendon to extend by ___%
1-3
How much is a tendon stretched during a walk?
3-8%
How much is a tendon extended at a trot ?
7-10%
How much is a tendon extended at a gallop?
12-16%
How much can a tendon extend before rupture?
12-20%
Scar tissue formation starts out with type ____ collagen and remodels over time to induce more type ___ collagen
3; 1
T/F: tendons enclosed in a tendon sheath have better healing than those not enclosed
False
Tendons in a tendon sheath have less efficient healing
What is tendonitis?
Inflammation of a tendon
Most commonly from overused, but can be from infection/injury
What are the 2 mechanisms of overstrain?
Sudden overload
Repetitive microtrauma (most common) —> molecular degeneration with progressively weakens tendon
Percutaneous trauma can clean to serious damage to the palmar aspect of the pastern/metacarpus. Extensor tendon lacerations rarely have long term consequences through, why?
Extensor tendons are non necessary for weight bearing in the horse
Why tendons are most prone to tendonitis/desmitis?
SDFT and SL
Take the most load during heel strike (landing)
Where do tears in the synovial cavities most commonly occur?
DDFT of forelimb
Manica flexoria of hindlimb
What are predisposing factors for tendonitis?
Anything increasing stress on the tendon/ligament
Poor ground
Inadequate training —>muscle fatigue
Poor confirmation —> long sloping pastern
Poor hoof care —> long toes or underrun heels
Improper bandaging//boots
What can you often find on PE of a horse with tendonitis?
Bowing of the palmar contour of the limb
Inflammation (heat, pain, swelling, lameness)
Severe lameness initially but once inflammatory phase has passed (1-2weeks) lameness resolves rapidly
Altered angles of limbs
What is the BEST tool for diagnosis of tendonitis?
Ultrasound
See hypogenic areas in the tendons if there is damage
When is the best time to do an ultrasound for tendonitis?
One week after injury
—> allows injury to fully declare itself
—> time for inflammatory process to decrease and better visualization
What type of US probe do you use to visualize tendonitis?
Linear 7.5-12MHz transducer
Evaluate transverse and longitudinal planes and both limbs
When doing US of the palmar aspect of the cannon bone, what structures are you visualizing from superficial to deep?
SDF, DDF check ligament, suspensory ligament
What tendons are you visualizing from superfiical to deep when doing US at the level of the fetlock?
SDF, DDF, seasmoid ligament
How does acute injury of a tendon appear on US?
Enlargement Hypoechgenicity Reduced striation Shape Margin or position changes
How does a chronic tendon injury appear on ultrasound?
Variable enlargement and echogenicity
Irregular situated pattern — > fibrosis
What method of imaging can be used for a suspected tendon injury that cannot be found on ultrasound?
MRI
What is the treatment for tendonitis?
All treatment regimens include rest and a controlled exercise program
Cooling, support and rest
What is the goal of treatment for tendonitis?
Restoration of the tensile strength of the tendon without peritendinous granulation tissue and adhesions
- reduce inflammation
- seed healing/return to work
- increase tensile strength
- decrease risk of re-injury
How long should you apply cold therapy for tendonitis
20mins
Cold hydrotherapy is better than ice packs
Why do we use compression and coaptation for tendonitis treatment?
Reduce inflammation/edema
Severe injury may require splint/cast
What types of intralesional injections can be done for tendonitis treatment?
Platelet rich plasma (PRP)
Stem cell therapy
Bone marrow
What are the benefits to platelet rich plasma for intralesional treatment of tendonitis?
Contains growth factors
Can provide scaffold for mesenchymal stem cell growth
Where are bone marrow stem cells taken from and what is the turn around time for the lab? How does this compare to adipose derived stem cells?
Tubercoxae or sternum with Jamshidi
3weeks for bone marrrow
48hrs for adipose (to lab), but can be don in 90mins if done in house
Why is bone marrow stem cell therapy better than adipose stem cell therapy?
Bone marrow can better differentiate into musculoskeletal tissue and provides growth factors
How does shock wave therapy improve healing from tendonitis?
Increase vascularization and growth factors in the area
Decreases pain
May reduce recovery time
What is the annular liagment?
Where superficial wraps around the deep to switch positions at the level of the pastern
Where does the superior check ligament attach?
From the SDF to the radius
What surgical procedure can you do to releive strain the on the SDF?
Superior check desmotomy
Strain is relive on the SDF but it is transferred over to suspensory ligament
A horse comes into your clinic, it has been lame for the past 2 weeks but has mildly improved with stall rest.
Over the RH pastern joint you see significant swelling above and below the joint with a narrowed constriction in the middle.
What is causing this and how would you treat?
Most likely effusion in the DDF tendon sheath, the constriction is caused by the annular ligament
You can confirm this with US —> should see hypogenic DDF and thickened annular ligament
Treat with an annular ligament desmotomy -> relieve pressure on DDFT
What is the most important comportment of treatment for tendonitis?
Rehab!
Strict rest initially, passive ROM
Hand walking followed by walking under saddle
Trot under saddle with prolonged walking for warm up and cool down
Canter with prolonged warm up and cool down
Slow return to exercise over months
Guided by several rechecks on US to check fiber alignment
Common causes of tendon laceration?
Trauma
Overload
Infection
What are the most commonly lacerated tendons in forelimb of the horse?
Common digital extensor
Lateral digital extensor
Usually between fetlock and carpus
- occurs from running into /jumping over objects
What are the most commonly lacerated tendons in the hindlimb?
Long digital extensor
Lateral digital extensor
Severance below hock
Flexor tendons
Usually between carpus/ hock and fetlock
(Kicking objects)
How can tendon lacerations be dignaosed ?
PE
— external lacerations
Radiology
—can see infection (gas producing bacteria)
US
Tenoscopy
Lameness
Horse has a slight drop in their fetlock, but the toe is not raised from the ground.
What tendon is lacerated?
SFT
Horse has a drop in the fetlock and the toe is lifted of the ground.
What tendons are lacerated?
SDF and DDF
Horse has compete drop of the fetlock where is is touching the ground.
What tendons are lacerated?
SDF
DDF
Suspensory ligament
Horse has an injury just caudal to the hock. How would you test for tendon laceration ?
You would hold the stifle in extension. Try to flex the hock..
Normal horse.. the hock and stifle flex and extend in unison due to reciprocal apparatus
Tendon laceration = hock can be flexed without flexion of the stifle
Calcaneus tendon AKA Achilles’ tendon
What tendon opposes the forces of the DDF and causes the toe to be elevated from the ground when DDF tendon is lacerated?
Common digital extensor
What are treatment options for tendon lacerations?
Corrective shoeing
— if you use a toe block in a cow, that toe must be healthy or it will fail because it is bearing all the weight
Bandage
Casts
Surgery
What are the surgery options for tendon lacerations
Suturing tendons back together —> locking loop
These often fail in the flexor tendons of large animals —> sutures pull through
Extensor tendons have good prognosis —> not weight bearing
