tendons/ligs (combo smallies + equine) Flashcards
stages of tendon healing
- Inflammation days 0-3
- Early proliferation days 1-7
- Late proliferation days 7-21d
- Remodelling up to 18months
describe process of inflammatory stage of healing
- blood clot formation stabilises torn tendon edges + scaffold for cells
- fibroblasts produce type III collagen
- macrophages remove devitalised tissue
describe process of early proliferation stage of healing
- angiogenesis commences
- tenocytes produce type III collagen
describe process of late proliferation stage of healing
- fibroblasts from epitenon + synovial sheath, intrinsic fibroblasts from endotendon
describe process of remodelling stage of healing
- type III collagen replaced by type I collagen
- rel. strength 56% @ 6wks, 80% at 1 yr
6 principles of tendon repair
- Clean the wound
- Appose tendon ends
- Placement of holding and circumferential sutures
- Reinforce the repair
- Immobilisation
- Strict post-op plan
3 parts of the common calcaneal tendon (dogs)
- tendons of gastrocnemius m. (paired)
- combined tenxons of gracilis, semitendionsus, biceps femoris muscles
- tendon of SDFT muscle
compare surgical approach to traumatic and atraumatic common calcaneal disruption
- traumatic usu. involves wound cleaning and minimal debridement of tendon (as acute - still viable) + apposition of ends w/ circumferential/holding sutures
- chronic atraumatic disruption usu. involves considerable debridement/resection resulting in limited tendon volume distally thus sx tx may involve tunnels, polyethylene terephthalate prosthesis
presentation of atraumatic common calcaneal disruption
1 Sign:. F>M, medium-large breed, dobermans, labs
- Hx: chronic progressive lameness w/ acute deterioration + no hx of trauma
- Px: thickened calcaneal tendon esp. at insertion
post-op care of common calcaneal disruption
tarsus maintained in extension for 6-8wks (bivalved cast, ESF, calcaneotibial screws)
px of common calcaneal disruption (dogs)
excellent (w/ sx) 72-94% success
failure to ID lacerations in the DDF tendon (concurrent to SDFT) may result in…
dogs
- flattened digits, weight bearing or metatarsal/carpal pad
- pressure sores
- chronic pain + lameness
bandaging regime for DDFT lacerations (dogs)
3 wks w/ foot in flexion followed by 3 wks w/ foot in normal weight bearing position
radiographic findings of biceps tendinopathy (dogs)
- intertubercular groove mineralisation, tendon mineralisations
req. orthogonal views + skyline
US findings of biceps tendinopathy (dogs)
- enlarged, hypoechoic tendon, fibre pattern disruption, irreg. synovium
why is MRI useful to investigate biceps tendinopathy?
concurrent assessment of intra-articular structures, substance tears, impingement ID w/ intra-articular contrast
medical tx of biceps tendinopathy
- Intra-articular methylprednisolone 1mg/kg 1-2doses 4-6wks apart
- Strict rest 4-6wks
sx tx of biceps tendinopathy
- tenodesis: good outcomes reported but implant assoc. complications
- tenotomy: preferred - can be arthroscopic
common lig/tendon issues in dogs
- common calcaneal disruption
- DDFT lacerations
- biceps tendinopathys
- traumatic lig injuries: collateral lig injury, carpal hyperextension
repair options for collateral lig injury (dogs)
- Primary repair w/ locking loop pattern
- Internal splint: augment + mimic action of ligament
- bone anchors, screws w/ washers
- bone tunnels, nylon sutures + wire
what structures may be damaged by carpal hyperextension in the dog?
- damage to flexor retinaculum, palmar fibrocartilage
- collateral ligs
rad dx of carpal hyperextension injuries
orthogonal views + stress rads
principles of arthrodesis
- Cartilage removed from all aspects of joints
- Cancellous bone graft placed in joints
- Apposed jt surfaces
- Rigid internal fixation
- Post-op immobilisation
- Follow-up rads @ 6-12wks
indications for arthrodesis in dogs
- implant failures for tendon repairs
- severe joint instability w/ primary repair not a viable option
complications of arthrodesis in dogs
- swelling, infection, dehiscence
- implant/fusion failure
- fractures
common equine tendon/lig issues
- Bowed tendons: flexor tendonitis
- Tendon lacerations: SDFT/DDFT/SL
3 Suspensory lig. desmitis - Palmar/plantar annular lig. constriction
- Tendon sheath injuries
predilection sites for bowed tendons
- forelimb (inc. weight bearing)
- mid cannon (narrow cross section)
inc. risk for bowed tendons
- wet track
- > 6yo
- conformation/shoeing
initial tx for bowed tendons
- Control inflammation (cold therapy, NSAIDs, bandaging)
- Limb support (Robert jones bandage, splint, heel elevation- DDFT)
- Stall rest
intra-lesional medications for tendon injuries (horses)
- IGF-1 (tendotrophine) + other GFs
- autologous bone marrow implantation
- stem cell therapy
- platelet rich plasma
potential surgeries for equine flexor tendonitis
- percutaneous tendon stab
- superior check lig desmotomy
- palmar/plantar annular lig. desmotomy (fetlock canal syndrome)
action of tendon stab/splitting
evacuates core lesion haematoma + may promote intrinsic healing
action of palmar/plantar annular lig transection
used to relieve tension on flexors in PAL constriction
action of superior check lig. desmotomy
inc. elasticity in muscle tendon unit
compare prognosis of flexor vs extensor tendon lacerations (horse)
extensor = excellent flexors = poor - fair dt inc. load and propulsive movements
tx of tendon sheath injuries
- tenoscopy + cont. lavage + regional limb perfusions + intralesional ABs
px of PAL post-sx
fair to good dependent on adhesions (chronicity) + damage to flexor tendons
proximal suspensoty desmitis blocks to what nerve block?
high 4 point
indications for neurectomy + fasciotomy w/ suspensory lig desmitis
chronic HL desmitis only
predilection sites for SL desmitis
HLs in STBs
FLs in TBs
- proximal
