Upper hindlimb (Yr 4) Flashcards
what are the three compartments of the stifle?
femoropatellar
medial femorotibial
lateral femorotibial
what compartments of the stifle communicate?
femoropatellar and medial femorotibial
what are the bones that make up the stifle?
distal femur
proximal tibia
patella
what are the patellar ligaments?
medial, middle, lateral
what are the soft tissue structures of the stifle?
medial, middle, lateral patellar ligaments
medial and lateral femoropatellar ligaments
medial and lateral collateral ligaments
cranial and caudal cruciate ligaments
medial and lateral menisci
why is it difficult to image the stifle?
lots of soft tissue structure around it (top of leg)
what radiographic views can we take of the stifle?
caudocranial
lateromedial
caudolateral-craniomedial oblique
what is highlighted on a caudolateral-craniomedial oblique view of the stifle?
caudomedial (medial femoral condyle)
craniolateral (lateral trochlear ridge)
why should you always image both stifles?
lesions are often developmental
what is the main site of osteochondritis dissecans (OCD) in the stifle?
lateral trochlear ridge
what is OCD?
osteochondritis dissecans
what horses usually present with OCD?
young horses (6 months - 4 years)
what is the number one site for OCD?
lateral trochlear ridge
how does stifle OCD present?
joint effusion
variable lameness (depends on where fragments sit)
how is stifle OCD diagnosed?
radiograph and ultrasound
how can stifle OCD be treated conservatively?
if <12 months old
dietary control and restrict exercise
monitor lameness
how can stifle OCD be treated surgically?
if >12 months old
removal of fragment
curettage of healthy subchondral bone (until it bleeds)
when should you do surgery of stifle OCD?
only if older than 12 months (fragments can reattach before this)
where are osseous cyst-like lesions found in the stifle?
medial femoral condyle
what are osseous cyst-like lesions also called?
subchondral bone cyst
when do horses present with osseous cyst-like lesions?
1-3 years old (and older) - later than OCD lesions
what are the clinical signs of osseous cyst-like lesions?
intermittent/severe lameness
joint effusions (medial femorotibial joint)
what is the main way osseous cyst-like lesions are diagnosed?
radiography
what are the treatment options for osseous cyst-like lesions?
intra-articular corticosteroids
inject cyst with corticosteroids
debride cyst and pack with bone graft
bone screw across cyst
what does prognosis of osseous cyst-like lesions depend on?
age of horse (much better in younger horses)
what is the best treatment for osseous cyst-like lesions?
injection of corticosteroids into cyst (still not that great)
what are some possible soft tissue stifle injuries?
meniscal and meniscotibial ligament injuries
cruciate ligament injuries (uncommon)
what can cause osteoarthritis of the stifle?
trauma/soft tissue injury
secondary to fracture
sequelae to sepsis
OCD/osseous cyst-like lesions
why is osteoarthritis of the stifle not good?
it is a very high motion joint
what are common clinical signs of stifle osteoarthritis?
moderate lameness
sore to flexion test
respond to diagnostic analgesia
what imaging is used for stifle osteoarthritis?
radiography
what is the prognosis for stifle osteoarthritis?
poor
what is the prognosis for complete femur or tibial fractures?
euthanasia required
what are common sites for upper hindlimb fractures?
tibial tuberosity
patella
what muscle inserts onto the tibial tuberosity?
patella ligaments
why does care need to be taken with possible tibial tuberosity fractures in foals?
tibial tuberosity has a separate centre of ossification so growth plates can look like fractures (radiograph the other leg!!)
how can we treat patella fractures?
repair them
remove if less than 1/3
what is the aetiology of upward fixation of the patella?
medial pole of the patella hooks over the medial trochlear ridge of the femur (normal part of stay apparatus) but then can’t unlock itself from this position
what are the two possible reasons for upward fixation of the patella?
patella ligaments too tight
quadriceps are too weak
what are the clinical signs of upward fixation of the patella?
poorly muscled or muscle loss
limb locked in extension and dragged (entire leg is rigid due to stay apparatus)
can be intermittent or persistant
how can upward fixation of the patella be treated?
exercise to build up quadriceps muscle
desmoplasty of medial patella ligament
how can you unlock an upward fixed patella?
walk horse backwards
manually move patella laterally
how common is coxofemoral joint pathology?
relatively uncommon
what are two possible conditions of the coxofemoral joint?
osteoarthritis
subluxation
what is the prognosis for osteoarthritis of the coxofemoral joint?
euthanasia (crippling lameness) - also very difficult to medicate the joint
what breeds is coxofemoral joint subluxation associated with?
miniature breeds
what are the common sites for pelvic fractures?
tuber coxae (traumatic)
ilial wing
ilial shaft (life threatening)
pubis/ischium
acetabulum
why are ilial shaft fractures life threatening?
iliac artery can be severed (usually require euthanasia)
what are the clinical signs of pelvic fractures?
pain/swelling/muscle spasms
lameness (variable)
signs of shock (haemorrhage)
nerve damage
muscle atrophy (if chronic)
how are pelvic fractures treated?
pain relief (NSAIDs)
box rest (cross-tie) - at least a month
what is the prognosis for pelvic fracture?
good for minimally displaced
poor for acetabular or ilial shaft fractures
what is sacroiliac disease?
ligaments of sacroiliac joint become strained/stressed leading to poor performance and lameness
what are the clinical signs of sacroiliac disease?
lameness (variable)
poor performance
pain on palpation
pelvic asymmetry (muscle wastage)
