Musculoskeletal Diseases Flashcards
Disease occurs when there is a disruption
of the normal physiologic function of a tissue or organ
Disruption of the musculoskeletal system may be the result of
Trauma, Degenerative disease, Inflammation, poor conformation, neoplasia
Etiology of long bone fractures
trauma, disease, repeated stress
Open fracture vs closed
open is through the skin
the classification of the fracture helps to determine
the best method of repair
oblique fracture
break occurs diagonally across the bone
Comminuted fracture
bone is broken, splintered, or crushed into pieces
Spiral fracture
break travels around the bone
compound fracture
the bone sticks through the skin
How many x-ray views are necessary to identify the type of fracture
at least 2
long bone fracture tx
reduction & fixation: splints, casts, intramedullary pins, bone plates, external skeletal fixation
How do bones heal
fracture hematoma, fibrocartilagnoius (soft) callus, bony (hard) callus, remodeling
a fractured bone will not heal without
stabilization/immobilization
What is ideal tx for simple fractures with closely apposed fracture segments
splint/cast
Intramedullary pins (IM pins) provide
good fracture site rigidity
What tx is ideal to prevent the forces of bending and rotation
IM pins
bone plates provide
excellent stabilization of most fractures
IM pins are not recommended for
distal forelimb fractures
External fixators are used primarily for
complex fractures or ones in which external wounds are present
an external skeletal fixator is a device consisting of
multiple pins and external rings or bars which hold a fractured bone in place during the healing process
Client education for fractures
restrict activity, leash walks only 6-8 weeks, surgical site care, follow up rads, additional sx or splint changes
What is the cruciate ligament
are ligaments which stabilize the knee located in x pattern and connect the femur to the tibia
2 cruciate ligaments
cranial and caudal
most common injury to stifle of a dog
injury of the cranial cruciate
injury of the cruciate causes
secondary degenerative joint disease (DJD)
CCL injury is seen frequently in
obese, middle-aged, inactive animals that suddenly hyperextend the stifle
dx of cruciate ligament injury
clinical signs, cranial drawer test (tibia slides forward over femoral condyles), tibial expression test, +/- joint effusion, rads
Client education for cruciate injury
rupture of contralateral ligament, sx is only way to repair and prevent DJD, activity restricted for 6-8 weeks, weight loss, anti-inflammatories,
what is a patellar luxation
the kneecap luxes or pops out of place either medial or lateral position
medial luxation common breeds
toy, mini, large
lateral luxation breeds
toy and mini, large and giant
One of the most common orthopedic conditions in dogs, dx in 7% of puppies
patellar luxation
Grading system for patellar luxation
Grade 1-5
patellar laxations that do not cause any symptoms should be monitored but do not typically
warrant surgical correction especially in small dogs
surgery for patellar luxation is most often considered with grades _ and over
2
Patellar luxation client education
sx may be warranted, post op care of sx site, activity restriction, anti-inflammatories , DJD likely
Genetic/hereditary condition most often seen in large breed dogs. Rapid weight grain and growth through excessive nutritional intake. Disease of the “ball and socket” may result due to abnormally shaped acetabulum and/or femoral head
hip dysplasia
Extra-articular stabilization
suture material placed around the casual fabellae and through a tunnel in the tibial crest to stabilize the joint
Intra-articular stabilization
Tibial tuberosity advancement (TTA) to prevent femur from skiing backwards off tibial plateau slope
Tibial plateau leveling osteotomy (TPLO) completely change dynamics of knee so the torn ligament becomes irrelevant to the stability of the knee itself
cartilage wear leads to
the formation of bone spurs and scar tissue, which are the characteristic signs of hip arthritis
Canine hip dysplasia (CHD) tx
not every dog will require tx. aggressive weight loss, walking, anti-inflammatories, rehab, supplements and special food. sx tx: total hip replacement or femoral head ostectomy
Hip dysplasia client education
OFA recommendations, weight loss, progressive condition, sx is the only cure
Legg-Perthes Disease (avascular necrosis)
necrosis due to loss of blood supply to femoral head which may be the result of s growth abnormally or trauma to the hip
Legg-perthes disease is a _ condition of small breed young dogs especially terriers, may also occur in cats and is common after trauma or injury to the leg or hip
hereditary
Tx of choice for legg-perthes disease
femoral head and neck ostectomy (FHO), larger dogs may require a total hip replacement
Osteochondrosis Dissecans (OCD)
abnormal development of the cartilage on the end of a bone in the joint. occurs rapidly growing medium to large breed dogs typically between 6-9 months
OCD diagnosis
radiographs and arthroscopic exam
Tx of OCD
rest, weight control, sx removal of flap, mice, or both
What is panosteitis
painful inflammation of the outer surface or shaft of one or more long bones of the legs
Panosteitis sometimes called
growing pains
Panosteitis common in
young, rapidly growing large breed dogs
Dx of panosteitis
rads reveal increased medullary opacity
Pathology of Coxofemoral luxations
tearing of the joint capsule and round ligament
tx of coxofemoral luxations
close or open reduction; Elmer sling placed for 7-10 days. consider other organ system that may be affected and tx accordingly
_ laxation are most common coxofemoral luxation
craniodorsal
Masticory myositis
involves the muscles of mastication (muscles contain a fiber that has antigenic properties similar to bacteria resulting in an inflammatory immune response)
myopathies are
rare in small animals but do occur
Most common musculoskeletal neoplasia
osteosarcoma
commonly affected site for musculoskeletal neoplasia
distal radius, proximal humerus, distal femur, proximal tibia
Dx of musculoskeletal neoplasia
rads reveal otic lesion within the bone that DOES NOT CROSS THE JOINT; metastasis check should be done: 3 view chest and 2 view abdomen
Client education for musculoskeletal neoplasia
amputation will remove primary tumor but not prevent metastasis, chemo risks and cost, fatal disease
90% of lameness in horses come from the
foot
Disease affecting the foot of horses
subsolar bruise (corn), hoof abscess, navicular syndrome, thrush, fractures
Etiology of subsolar bruise
trauma that causes solar hemorrhage
etiology of hoof abscess
bacteria within hoof capsule
clinical signs for hoof abscess
fever, lameness, increased palmar digital pulses, feltock and pastern swelling
Etiology of navicular syndrome
inflammation of navicular bursa; excessive strain on flexor tendons; improperly trimmed hooves
Pressure applied to the frog area by a hoof tester will cause ___ if navicular disease is present
the horse to flinch
Etiology of thrush
bacterial infection of frog: Fusarium necrophorum; WET CONDITIONS
Sidebones
ossification of the collateral cartilages. found on either side of the foot protruding above the level of the coronary band
etiology of sidebones
direct trauma to the foot
Sesamoiditis is due to
great stress placed on the fetlock during fast exercise, the insertion of some of the ligaments can tear, which can result in inflammation and pain in this region
Bucked shins
a painful acute periostitis on the cranial surface of the large meta-carpal or metatarsal bone
etiology of splints/fractured splint bones
Splints:mineral and vitamin imbalances, faulty conformation
Fractured splint bones: direct trauma to bone
Laminitis
Inflammation of the sensitive laminae; occurs when an insult causes blood to bypass the dermal laminae
Extreme vasoconstriction causes the sensitive laminae to
separate from insensitive laminae and the coffin bone rotates away from the hoof wall bc of the pull from the deep digital flexor tendon
Shoulder sweeny
damage to the supra scapular nerve, resulting in atrophy of the shoulder muscles
Bog spavin referes to
a chronic synovitis of the talocrural joint characterized by distention of the joint capsule
Bone spavin refers to
osteoarthritis or osteitis of the distal intertardal and tarsometatarsal articulations and occasionally the proximal inter tarsal joints
Etiology of bone spavin
stress on the hock as a result of trauma
Rhabdomyolysis aka external myopathy, exercise induced myopathy, Monday morning disease
a syndrome of muscle fatigue, pain, or cramping associated with exercise
Hyperkalemic periodic paralysis (HYPP) aka impressive syndrome
a genetic disorder that occurs in horses. affects sodium channels in muscle cells and the ability to regulate potassium levels in the blood
Clinical signs of HYPP
muscle trembling, prolapse of 3rd eyelid, generalized weakness, weakness in hind in, complete collapse
Nutritional secondary hyperthyroidism aka big head disease
improper ration (high P, low Ca) causing enlarged facial bones, spontaneous fractures, intermittent shifting leg lameness
Etiology of infectious footrot
bacteria Dichelobacter nodosus
Infectious footrot clinical signs
lameness in more than one individual of the herd, malodorous discharge, interdigital dermatitis
Septic arthritis etiology
penetrating wound near a joint; umbilical infection
etiology of Caprine arthritis encephalitis (virus) and clinical signs
retrovirus; chronic progressive arthritis, carpal swelling
Caprine Arthritis Encephalitis transmission
vertical (doe to kid via nursing)
Etiology of Nutritional Muscular dystrophy (white muscle disease)
selenium deficiency
Clinical signs of white muscle disease
cardiac: recumbency, dyspnea, tachycardia
muscular: stiff gait, muscle tremors, dysphagia
Etiology of rickets and osteomalacia
lack of vitamin D, lack of calcium and phosphorus
Rickets and osteomalacia clinical signs
stiff gait, recumbency, enlarged costochondral junction
etiology of ergot toxicosis
ingestion of the funds claviceps purpurea (contaminated grains or fescue pastures)
Pathogenesis of ergot toxicosis
Vasoconstriction by direct action on the muscles of the arterioles and repeated doses injure the vascular endothelium
clinical signs of ergot toxicosis
distal limb discoloration and swelling; lameness of hindlimbs
