LA Ortho - Hindlimb Lameness Flashcards
Tarsus
# of compartments
Numerous articulations
4 synovial compartments
Numerous ligaments
Radio views for the tarsus
Lateromedial
Dorsopalmar
DLPMO
DMPLLO
Causes for tarsocrural joint effusions
Idiopathic
Synovitis/capsulitis
Conformation
Osteochondrosis
Fracture
Desmitis
Septic arthritis
“Bog spavin”
Calcaneal bursitis
Aka capped hock
Swelling of sub q or sub tendon bursa
Synovitis of tarsal sheath
Idiopathic effusion of tarsal sheath
Swelling cranial to point of hock
Typically asymptomatic
Requires no treatment
Thoroughpin
Synovitis of tarsal sheath
Treatment for thoroughpin
Cryotherapy
Rest
IA meds
HA, IRAP serum, Cortsteroids
Arthroscopic surgery
Antimicrobials if septic
OA in Tarsometatarsal & distal intertarsal joints
Tibiotarsal & proximal intertarsal NOT involved
Usually due to wear & tear
Repeated compression/rotation
Poor conformation
Therapeutic goal for TMT and distal IT joints
Pain relief/ recovery of soundness
Not cartilage preservation - want to remove cartilage
Can get away with the removal of cartilage bc
- low motion joints
- slow disease progression
- joint fusion is the goal
Medical treatment for TMT & distal IT joints
Want the joint to get worse which will help the joint get better - keep them comfortable to keep them working
Corrective shoes
NSAIDS, Cortsteroids
HA
PSGAG
Nutraceuticals
Arthrodesis
Surgical/chemical
Surgical - drill across joint space
Chemical - 70% ethyl alcohol = protein destruction
Clinical presentation for ligament injury
Synovial effusion
Soft tissue swelling
Curb
Injury to the plantar ligament
Tarsal luxation
Due to trauma
Acute severe lameness, ST swelling, instability
Radiographs @ stressed views
Treating a tarsal luxation
Full limb cast (foot to stifle)
Internal fixation if fractures
Prognosis for tarsal luxation
Pasture joint - fair to poor
Depends on degree of lig damage
Stifle
# of compartments
Ligs involved
3 synovial compartments
- femoropatellar
- lateral & medial femorotibial
Collateral ligs
Patellar ligs
Menisci
Cruciate ligs
Causes for stifle effusion
Idiopathic
Synovitis /capsulitis
Osteochondrosis
Fracture
Soft tissue injury
Septic arthritis
OA development in stifle
Chronic use - high motion joint
Trauma
Meniscal tears
Cruciate tear
Joint instability
Untreated OCD
Prognosis for OA in stifle
Depends on cartilage damage, bone remodeling, joints involved, ST damage, progression
OCD in general
Most common clinical sign - synovial effusion
Degree of lameness (often in young horses)
Flexion test - mild positive
Radiograph bilaterally
common sites for ODC in tarsus
Distal intermediate ridge of tibia
Lateral trochlear ridge of talus
Medial trochlear ridge of talus
Medial + lateral maleoli of tibia
Prognosis of OCD
Depends of severity of cartilage damage & bone remodeling
Age @ treatment/duration - better if treated arthroscopically at young age
Prognosis % of ODC
77% return to racing when fragments are surgically removed
Resolution of synovial effusion 74-83% resolve
Upward patellar fixation
Young developing horses, minis, ponies, Donkeys
Intermittent - Mild catching of patella during flexing, self correcting
Permanent - severe lameness, unable to manually correct
Diagnosing for UPF
Clinical signs and signalment is very obvious
Pathophys of UPF
Problem w releasing the passive stay apparatus
Muscles could be developing too slow for how quickly the skeleton is growing
Role of quadriceps femoris in UPF
Quadriceps fem is under conditioned & unable to lift patella up/off the medial trochlear ridge of femur to release stay apparatus
Intermittent UPF treatment
Modify training to target quadriceps femoris
Inject counter irritants into medial patellar lig
- creating a controlled amt of inflammation, promotes scar tissue formation
Surgical approach for UPF
Desmoplasty
Split the medial pat lig
Stimulate growth, lay down new collagen
Prognosis for UPF
Good but depends on
Response to conserv therapy
Response to MPL splitting
MPL desmotomy - last resort, will develop OA
Stringhalt forms
Classic (idiopathic) - often unilateral
Australian form - due to dandelion ingestion - bilateral
Characteristic gaits w stringhalt
Observe at walk or trot
Involuntary /exaggerated flexion of one or both hind limbs
Limb jerked upwards in cranial phase of stride
Diagnosing stringhalt
Observe exaggeration in gait
Presence of toxic dandelions and evidence of lack of forage
Treatment & prognosis of stringhalt
Prevent ingestion of dandelions (50-78% spontaneously recover)
Lateral digital extensor myotenectomy
Cut muscle proximally & tendon distally (leaving the long digital extensor)
Shivers - clin signs
Gradually progressive, chronic neuromuscular disease
Results in gait abnormalities when backing or working on hind feet, trembling tail when held erect, trembling of thigh muscles (shivers), flexed & trembling hind
Diagnosing shivers
Differentiate from string halt
Commonly found in draft horses
No treatment and prognosis is variable
Fibrotic myopathy - diagnosis
Traumatic etiology - sliding stops, sharp turns on hind
Palpable fibrosis of Semitendinosus (membranous)
Abrupt cessation of cranial phase of stride of effected limb
Foot jerked caudally just before it hits the ground
Treatment and prognosis for fibrotic myopathy
Semitendinosus tenotomy
Cut tendon of insertion of medial side of leg, displaces loading more freely
Few surgical complications, improvement is to a variable extent
Ruptured gastrocnemius muscle
Depends on partial or complete - inability to fix stay apparatus
Treat w stall rest & stabilization
Foals - favorable prognosis
Adults - poor for complete ruptures
Ruptured peroneus tertius muscle
Diagnosis - abilit to extend tarsus while stifle is flexed
Stall rest - 6 weeks, controlled exercise 3 months
78% return to previous exercise, 21% euthanized
