Equine tendon and ligament disease Flashcards
Name 2 types of tendon injury
- percutaneous: laceration/ penetration
- subcutaneous - strain, displacement
Causes of over-strain injury
- sudden over-extension (DDFT?)
- preceding tendon degeneration with superimposed sudden over-extension (SDFT, SL)
Dx - tendon injry
- Hx (usually preceding intense period of exercise, signs can be delayed)
- CE - lameness (can be temporary, can persist for some tendon/ligament injuries)
- Stance/ gait - MCPJ extension (decreased with reduced weight bearing / pain and fibrosed/ stiff tendon. increased with severe SDFT/SL injuries. Elevating toe - DDFT rupture
What is a pathognomic sign for DDFT rupture?
toe elevation
How should you palpate the limb? 2
- weight bearing
- limb lifted
Which areas are difficult to palpate? 2
- proximal SL in HL
- pastern
What to assess on palpation? 3
- pain
- tendon suppleness
- oedema
What is the role of ultrasound?
- DIAGNOSIS
- SEVERITY ASSESSMENT: 7 d after injury, prognosis
What ultrasound equipment is used to examine the leg?
7.5 MHz (high frequency) + linear transducer
Describe SDFT tendinopathy
- palmar metacarpal swelling
- initial lameness (variable)
- pain on palpation
- ‘core’ lesion on ultrasound
Hx - suspensory ligament desmitis/ proximal suspensory desmitis
- HX: lameness variable in degree, acute or insidious
- CS: conformation (HL) is straight hock adn overextending MTP joint
CS - proximal suspensory disease
- Lameness (often lamer with limb on outside of circle, proximal MC/MT swelling is variable and with medial palmar vein distension, pain on palpation vs normal)
- diagnostic analgesia
- diagnostic imaging (US, xray, gamma-scintigraphy, MRI)
Suspensory body and branch desmitis:
- CS
- Ultrasound
- Radiograph
- CS: variable lameness
- ULTRASOUND: branches need imaging from medial and lateral aspects, focal or generalised lesions, enlargement, periligamentar fibrosis very common, bilateral involvement common
- RADIOGRAPH: concurrent bony abnormalities
Define ALDDFT
Accessory Ligament of the DDFT (= ‘accessory check ligament’)
CS - desmitis of the ALDDT (‘inferior check ligament’)
- swelling in proximal MC region, mostly lateral
- dorsal to SDFT
- lameness variable (often absent)
Ultrasound - desmitis of the ALDDT (‘inferior check ligament’)
- generalised enlargement
What happens in DDFT tendinopathy?
- usually within digital sheath or navicular bursa (never in MC region?)
- mid-substance disruption vs. border tears
- e.g. intra-thecal tendon tears
What is the manica flexoria?
part of the SDFT that wraps around the DDFT at the fetlock joint. Function is to maintain tendon alignment within DFTS.
Examples of intra-thecal tendon tears
- DDFT (usually lateral border for tear, TL)
- Manica flexoria (usually HL)
Ultrasound diagnosis: intra-thecal tendon tears
- difficult
- lateral or medial echogenic material
- MF instability in longitudinal view
Causes - tenosynovitis
DIGITAL SHEATH:
- idiopathic distension
- non-septic inflammation (primary, most secondary)
- penetrating injuries (sepsis)
What is tenosynovitis important?
because the dysfunction results in important consequences for soft tissues and bone
Define ALS
Annular Ligament Syndrome
CS - ALS
- Lameness (mild-moderate, minimally responsive to rest, occasionally irregular gliding of tendons)
- distended digital sheath
- ‘notch’ at level of PAL
Diagnosis - ALS
- Digital sheath analgesia (usually positive but may not be 100%, may have a mechanical component to lameness)
- Ultrasonography (+tenoscopy, look for if >2mm thickness)
General principles -tx of tendonitis
- many tx advocated in past (many have no effect, some are deleterious)
- very few EBVM choices
- base tx on tendon pathology and phases of tendon healing
What are the 3 phases of tendon healing?
- acute/ inflammatory
- subacute/ fibroplasia
- chronic/ remodelling (never back to normal)
- 12-18 months for tendon repair
- 3-6 months for ligament repair
Acute inflammatory phase of tendonitis (0-2 wks):
- CS
- Pathology
- Rational tx
- CS: lameness, pain on palpation, heat, swelling
- PATHOLOGY: haemorrhage and inflammation (neutrophils, macrophages and monocytes, increased BF, oedema, proteolytic enzymes)
- TX: minimise inflammation
Describe tx of acute inflammatory phase of tendonitis
- PHYSICAL THERAPY: apply cold/ ice, compression, MCP joint support (rest)
- MEDICATION: short-acting steroids (only within 24-48 hours, systemic or peritendinously, beware of laminitis and masking problem), NSAIDs (analgesia)
- SURGERY: percutaneous tendon splitting (knife, needles, may combine with intra-tendinous meds)
Subacute/ reparative phase of tendonitis (1 wk - 6 mo):
- CS
- Pathology
- Rational tx
- CS: reduction or absence of lameness, resolution of signs of inflammation, tendon still palpably enlarged and soft, signs of re-injury if exercised too early
- PATHOLGOY: angiogenesis, fibroplasia (many fibroblasts, collagen 3, small collagen fibrils formed)
- RATIONAL TX: promote fibroplasia, optimise scar organisation, regular US monitoring (every 2-3 months, exercise level based on CSA), mobilisation (early, progressive - introduce trotting 3 months after SFDT injury), biologicals
What biological tx may be given for tendonitis? 3
- scaffolds (ACell = lyophilised pig bladder submucosa
- growth factors (platelet rich plasma = PRP)
- cell therapy (mesenchymal SCs)
Outline method of mesenchymal SCs for tendonitis
- recovery of heparinised bone marrow from 2 separate sternebrae
- located with diagnostic ultrasound
- recovery of nucleated adherent SC population
- one passage
- resuspension in citrated supernatant of BM
- implantation under USG
- post-implantation 48 wk rehab programme
Chronic phase of tendonitis (3-18 months):
- CS
- Pathology
- Rational Tx
- CS: tendon size decreases, tendon less pliable, reduced fetlock extension, (contractures)
- PATHOLOGY: collagen transformation from 3 to 1, cross-linking, thicker collagen fibrils
- RATIONAL TX: promote remodelling, prevent re-injury
Outline tx for chronic phase of tendonitis
- controlled ascending exercise (lower exercise level)
- US monitoring
- Surgery: desmotomy of the accessory ligament of the SDFT (‘superior check ligament’), higher incidence of suspensory desmitis, carpal sheath approach)
When is extracorporeal shock wave therapy indicated?
- Proximal Suspensory Desmitis (PSD): both TL and HL
When is fasciotomy and neurectomy therapy indicated?
For HL PSD which have failed to improve after the first 2 tx of extracorporeal shock wave therapy
What is extracorporeal shock wave therapy?
high energy pressure waves to pulverise the proximal suspensory region
How might you tx intra-thecal tendon/ligament lesions?
- medication?
- intrasynovial location gives poor healing
- tenoscopy/ arthroscopy
How might you tx HL manica flexoria tears?
good prognosis with removal (70-80%)
How might you tx TL DDFT tears?
debridement but poor prognosis (20-40%)
List some developmental diseases of tendon
- flexural limb deformities
- carpal flexural deformities
- DIPJ flexural deformity
- MCPJ flexural deformity
- tendon laxity
Describe flexural limb deformities:
- what
- aetiology
- tx
- tendon developmental disease
- AETIOLOGY: congenital (possibly uterine malpositioning or CDET rupture) or acquired (part of ‘developmental orthopaedic disease’, pain (OCD, physitis etc)
- TX: conservative (start with this, exercise, shoeing, splints), then surgical release if unsuccesful
Describe carpal flexural deformity
- what
- aetiology
- tx
- tendon developmental disease
- congenital
- TX: exercise and physio (most cases respond to this), then tube casts, (sx)
Describe DIPJ flexural deformity:
- what
- aetiology
- types
- tx
- adults
- tendon developmental disease
- acquired (6 months old)
- TYPE 1: dorsal hoof wall less than vertical
- TYPE 2: dorsal hoof wall past vertical
- Pain-related? –> NSAIDs
- ADULTS: TL –> chronic lameness, HL = usually desmitis of the ALDDFT
Another name fro DIPJ flexural deformity
‘ballerina foals’
Tx - type 1 DIPJ flexural deformity
- exercise and physio
- toe extension shoe
- sx (desmotomy of ALDDFT, (DDFT tenotomy))
Tx - type 2 DIPJ flexural deformity
- usually sx necessary
- desmotomy of ALDDFT
- (DDFT tenotomy)
Describe MCPJ flexural deformity
- also can occur secondary to chronic SDFT tendinopathy in adults
Tx - MCPJ flexural deformity
- exercise/ physio
- toe extension and raised heel shoe
- splints/ braces (beware of sores!)
- sx (desmotomy of ALDDFT, desmotomy of ALSDFT, SDFT tenotomy)
Describe tendon laxity:
- congenital
- acquired (secondary to casting)
- Tx: spontaneous recovery, heel trimming, heel extension shoe, controlled exercise)
