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
