Lameness Flashcards
What injury causes a ‘palmar bow’
SDFT
Clinical signs of inflammatory phase after tendon injury
Lameness
Pain on palpation
Heat
Swelling
Clinical signs of reparative/proliferative phase after tendon injury
Reduction or absenceof lameness
Resolution of signs ofinflammation
Tendon still palpablyenlarged and soft
Signs of re-injury ifexercised too early
Clinical signs of remodelling/maturation phase after a tendon injury
Tendon size decreases
Tendon less pliable
Reduced fetlock extension
Contractures
What is the length of the inflammatory phase after tendon injury?
Days
What is the length of the reparative/proliferative/fibrosis phase after tendon injury?
Weeks
What is the length of the remodelling/maturation phase after tendon injury?
Months
What cells are present in the inflammatory phase of tendon healing?
Neutrophils, macrophages, monocytes
What cells are present in the reparative/proliferative (fibrosis) stage of tendon healing?
Fibroblasts (++)
What collagen type is present in healthy tendon?
Collagen type I
What collagen type is present in tendon after injury?
Collagen type III
What is occurring with collagen in the tendon in the remodelling/maturation phase of tendon healing?
Transformation from type III to type I
What are the 4 things affecting the structural properties of tendons?
Crimp
Glycosaminoglycans (GAGs)
Cartilage Oligometric Matrix Peptide (COMP)
Collagen
Why are tendons more predisposed to injury as horses age?
Crimp and COMP reduce with age
What does this shoe do?
Heartbar shoe
Pedal bone support (load transferred from hoof wall to sole and better loading of heel region)
Modern technologies offering improved benefits to the heart bar shoe
Pads (raised profile where frog sits)
Resins and impression materials (injected into space between pad and sole to reduce concussion and transfer force across whole sole)
Benefits of heart bar shoe, pads or packing in laminitis?
Pedal bone support
Benefits of heart bar shoes in navicular syndrome/palmar heel pain
Restrict independent heel movement
How can you immobilise a pedal bone fracture in the acute phase of injury to speed up healing?
Heart bar shoe and packing
How can you reduce concussive and contusive forces on the sole of the foot in horses prone to bruising?
Pads and packing
Do horses with poor confirmation benefit from farriery/additional support?
Yes, reduces pain and improves confirmation
How does a bar shoe help after keratoma resection?
Foot is structurally compromised
Why are graduated shoes indicated in DDFT tear within the foot?
Reduce strain on DDFT because it doesn’t have as far to travel. Offloads tendon and reduces pressure applied to the navicular bone. Raised heel also alters breakover to reduce pressures applied to distal interphalangeal joint
Are graduated pads a long or short term solution to lameness? Why?
Short-term
Horses with heel pain already have poor foot conformation (long toe, low heel, thin sole). Raising the heel contributes to poor conformation as it encourages the heel to grow parallel to the shoe (hoof make end up worse than before treatment)
Pathways to arthritis (2)
Abnormal cartilage
Abnormal stress on normal cartilage
Components of cartilage
Chondrocytes
GAG
Collagen
Water and mobile ions
Hyaluronic acid
Clinical signs of joint problems (in order of increasing severity)
Synovitis
Partial thickness cartilage erosions
Full thickness erosions
Subchondral bone lesions
Peri-articular new bone
Peri-articular soft tissue damage (including collateral ligaments)
Peri-articular fibrosis
Joint ankylosis
Which joints can often have extreme radiographic changes (lysis, new bone formation, ankylosis) but minimal lameness?
Low motion (proximal interphalangeal or distal tarsal joints)
What % response to a joint block is considered a positive response and why?
50% or above (pain can come from periarticular soft tissues and subchondral bone which don’t block completely)
Main changes in joint fluid with OA
Reduction in viscosity (due to lack of GAGs and hyaloronic acid)
Protein levels and cell count may be normal
Considerations when assessing orthopaedic pain
Lameness severity score
Mobility, behaviour and interactions
Grimace/pain face scoring
Behaviour when ridden
Treatment options for osteoarthritis in a low motion joint
(Goal is fusion of joint)
Intra-articular steroids
Systemic NSAIDs
Neurectomy
Chemical arthrodesis (tarsal joints only)
Surgical arthrodesis
Contraindications for chemical arthrodesis
Never use in proximal intertarsal joint as it communicates with the high motion tarsocrural joint
What can be injected into the joint in chemical arthrodesis for osteoarthritis?
Monoiodoacetate (MIA)
Ethanol
