
Movement

Shape of body


Trauma
– Fracture
– Ligament Rupture

Degenerative disease
– Osteochondritis dissecans (OCD)
– Degenerative joint disease (DJD)
– Ununited Anconeal Process (UAP)


Inflammation
– Myositis
– Panosteitis

Poor conformation
– Luxating patella

Neoplasia
– Osteosarcoma


Usually painful, need analgesics
– Feel better, heal better, eat better, etc

Fractures
– Causes

Other traumas

Bone disease

Repeated stress


Fractures
– Types

Open (compound) – broken skin

Closed – intact skin

Simple – 1 break

Comminuted –multiple pieces

Stable – ends apposed and fixed (ie greenstick)

Unstable

Compression


Signs
– History of trauma
– Pain or localized tenderness
– Lameness
– Deformity of bone
– Loss of function
– Localized swelling or bruising

Dx – X-rays



Stabilize joints above and below the fracture
External devices
– Splints

Permanent or temporary

Wood, metal, plastic, newspaper

Adequate padding – protect limb

Keep dry, decrease activity

Foul odor => necrotic tissue, infection

Swollen toes => too tight


Casts
– Plaster of Paris, fiberglass
– Permanent

Robert Jones bandage plastic splint metasplint application
Schroeder-Thomas splint


External fixation


Rx
– Internal fixation devices

Intramedullary pin
– Provides good stability along axis of bone
– Rotation can be problem
– Removed after fracture heals
– Sterile surgical condition


Comminuted fracture

Best stabilization

Should be removed after healing – most are not

Requires specialized instruments and surgery techniques

Provides early return to function


Which bone? Where is fracture?

 http://www.youtube.com/watch?v=
Wls_Pyop-D0&feature=channel_page


Restrict activity

Watch for drainage, swelling, heat

Metal (plate, pin) stronger than bone
– refracture may occur

Follow up x-rays necessary

Metal should be removed after healing

Metal may cause cold sensitivity


ACL and PCL (posterior cruciate ligament) stabilize knee joint

Intra-articular structures

Ruptured ACL – most common knee injury => DJD

May be complete rupture or partial tear => unstable joint => DJD







Occurrence – sudden hyperextension or lateral extension of knee during exercise
Middle age, obese, inactive or highly athletic dogs; rare in cats
Sudden non weight bearing or limping
Swelling of knee joint
Rupture of contra lateral ACL often occurs within 1 year
Mensical tear often accompanies ligament tear


Anterior drawer movement


Surgical stabilization most successful
– Goal: stabilize knee to return function and minimize DJD
– Extra capsular stabilization

Most successful <30#

Suture material from flabella to tibial crest and imbrication of joint

 http://www.youtube.com/watch?v=9 jg9E2nBt_E&feature=related
 http://www.youtube.com/watch?v=4 nU2QZjjByg
 http://www.youtube.com/watch?v=-
1pxxX4TXko&feature=fvw








Restrict activity 3-4 weeks post surgery
– Cage rest
– Leash walk only to urinate and defecate
Gradually increase exercise 4-8 wks post sx
Full activity 8-12 weeks
Opposite cruciate often tears within 1 yr
Weight loss helps
DJD of stifle joint likely
If no surgery, joint thickens - fibrosis


Grades
– I - Patella manually displaced but pops back into place
– II – Spontaneously or manually displaced till manually repositioned or patient extends stifle joint
– III – Patella luxated most of the time but can be manually replaced; movement of stifle joint reluxates patella
– IV – patella permanently luxated; unable to replace


Grades III and IV – crouching, bowlegged or knock-kneed stance for medial or lateral luxations, respectively

Pain: occurs as patella relocates or abrasion creates contact with bone


Patella is in circle

Patellar groove indicated by arrow
Patella out of groove
Patella in groove

Seen in older dogs as the soft tissue of stifle deteriorates; often accompanies hip dysplasia
Produces more functional disruption than medial luxation

Clinical signs
– Acute lameness often associated with trauma or strenuous exercise
– Knock-kneed stance is sometimes seen
– If bilateral, animal may be unable to stand






75% of cases
1 of most common stifle joint abnormalities in dogs
Bilateral involvement - 50% of cases
May occur in cats but not suspected, not lame
Clinical signs
– Usually bilateral
– Young (5-6 mo)
– Cow-hocked (knock-kneed)
– Foot twists laterally when weight bearing
– Skipping or intermittent hindlimb lamesness


Dx
– Toy and miniature dog breeds (yorkies,
Poms, Pekes, Chihuahuas, Boston terriers
– Palpate patella when knee is flexed
– X-rays show deformity and patellar displacement


Diagnostics
– Labs - ?
– X-rays – indicated for Grade III & IV luxations
– Arthrocentesis/synovial fluid analysis – minimal changes


Treatment
– I & II – outpatient treatment

NSAIDS – minimize pain, decrease inflammation

No steroids: SE and articular cartilage damage in long term use

+/- chondroprotective drugs – glucosamines, chondroitin sulfate


Treatment – II, III & IV –
– Surgical repair only option

Deepen trochlear groove

Tibial crest transposition for malalignment

Imbrication of joint capsule to stabilize patella in groove


Rx
– Surgical repair is only treatment
(3 surgical options)
– 1) Deepen trochlear groove


1A) Trochlear block resection (also deepens trochlear groove)

2) Transposition of tibial crest
Medial luxation patella

 http://video.google.com/videosearch
?hl=en&q=patella+luxation+surgery
&um=1&ie=UTF-8&sa=N&tab=wv#
 http://www.youtube.com/watch?v=G fnQbIk284g


Client info
– After Sx, limit exercise for 2-3 wk
– Support bandage (1-2 wk) should be kept dry
– NSAIDs for pain relief
– Ice pack for 5-10 min q 8 hrs for 3-5 days post surgery
– Physical therapy for rehab (swimming) helpful for animals reluctant to bear wt
– Will probably have some DJD later in life


Client Info
– May be inheritable
– Can worsen overtime esp without surgery



Def: Malformation and degenearion of the coxofemoral joint
Pathophysiology
– Developmental defect initiated by a genetic predisposition to subluxation of the immature hip joint
– Poor alignment between femoral head and acetabulum => abnormal forces on joint=> irregularly shaped acetabula and femoral head
– Also overload articular cartilage => microfractures and osteoarthritis


One of most common skeletal diseases in dogs

Incidence in cats lower that dogs

Breeds: Large breed dogs – St. Bernards,
G. Shepherds, Labs,
Golden Ret,
Rottweilers


Lowest prevalence are nearest in size to ancestral dog
Collie
– skin is tight, thin, smooth
Doberman
Collie
– slender/trim
Dalmatian
I Wolfhound
– muscles are full, hard
G Shorthair
– low fat % (1-2%)
– fleet footed, well-coordinated
Afghan hound
Belgium Tervuren
Siberian Husky


Highest prevalence
– giant breeds (2-3 x ancestral dog)
St Bernard
– bones are coarse and large Newfoundland
Bull mastiff
– feet are large and splayed
Eng Setter
– head is wide/oversized Gordon Setter
OE Sheepdog
– heavy, round, stocky
S Spaniel
– fat % (5-10% of ancestral dog) Akita
– muscles less developed
Ches Bay Retriever
G Retriever
– less graceful, slower Elkhound
Rott
– Grow/mature rapidly

G Shep
Within a breed, the faster growers are more prone to
HD

Pups of wolves, foxes are slow growing, late maturing vs dogs



Depends on degree of joint laxity, OA, and chronicity of disease
– Early – related to joint laxity
– Later – related to jt degeneration
– May present as early as 4-5 months
HX
– Decreased activity


Difficulty rising
Reluctance to run, jump, climb
– Intermittent or persistent hind limb lameness; worse after exercise
– Bunny hopping or swaying gait
– Narrow hind limb stance


Pain on palpation of hips

Joint laxity (positive ortolani sign) – early disease – subluxation of hip

Crepitus

Decreased ROM of hip joints

Atrophy of thigh muscles

Hypertrophy of shoulder muscles


Dx
– X-rays provide definitive diagnosis

Quality depends on positioning, exposure technique, darkroom technique
– VD position
– Hind limbs extended fully and parallel
– Totally rotate legs medially
– Bilateral symmetry
– Flattening of femoral head,
– Shallow acetabulum
– Periarticular osteophyte production
– Thickening of femoral neck


OFA Certification
– Anesthesia/sedation usually required for positioning
– OFA requires animals to be >2 yr of age; 7 grades of hips


Excellent—near perfect hips
Good—normal





Fair—less than ideal, but within normal limits
Near normal—borderline conformation
Mild Dysplasia—minimal deviation with slight flattening of femoral head
Moderate Dysplasia—
Severe Dysplasia—complete dislocation of hip w/ flattening of acetabulum and femoral head


Normal hips
– round head except where lig of femoral head attaches
– Joint space (J) is consistent

Borderline —no consensus between radiologists to classify hip as Normal or Dysplastic

Good positioning
Normal dog
Poor positioning
1.
femurs not parallel
2.
Obturator foramen less rounded on R and wing of ileum larger on R
3.
R acetabulum appears shallower
4.
L acetabulum appears deeper
5.
Fabellae appear more medial to femur midline
6.
Wedge-shaped jt space due to lateral femoral rotation (looks like HD)


Penn Hip Registry – distraction radiography

Dorsolateral subluxation (DLS)

Dorsal acetabular rim view x-rays


Medical
– Outpatient
– Analgesics and Antiinflammatories

Minimize joint pain=> use legs => decrease atrophy
– Does not correct problem; degenerative process progresses anyway
– Temporary relief of pain
– Carprofen, erodolac, deracoxib, tepoxalin
– Avoid corticosteroids – articular cartilage damage in long term use
– Do not combine NSAIDS
– Do not combine NSAIDS with steroids
– Wait several days when changing NSAIDs
– Glucosamine and chondroitin sulfate supplements chondroprotective


Surgical
– TPO – triple pelvie osteotomy

6-12 months age

Preventive to correct alignment of joint
– Juvenile Pubic Symphysiodesis

Pubic symphysis fused early

Causes better alignment of acetabulum with femoral head

Can be done 3-4 months; minimal effect after 6 mo


Surgical
– Total hip replacement



Salvage procedure in mature dogs with severed DJD unresponsive to medical Tx
Pain free in 90% of cases
Unilateral replacement provides acceptable function in 80% of cases
– Excision Arthroplasty or Femoral Head
Ostectomy



Forms “false” joint
Removal of femoral head and neck to prevent joint pain
Salvage procedure when medical treatment not working and other sx too expensive


Best - < 20#; good musculature
Abnormal gait

 http://www.youtube.com/watch?v=H
Twi8TRs6z8







Weight control important to decrease load on painful joint
Swimming excellent activity
Physiotherapy – decreases joint stiffness, helps maintain muscle integrity
Joint degeneration progressive
May be heritable – do not breed
Special diets designed for fast growing dogs may decrease severity







Spontaneous degeneration of the femoral head and neck leading to collapse of the coxofemoral joint and osteoarthritis
Avascular necrosis of femoral head and neck
Cause unknown
Infarction of the blood vessels of the proximal femur
Necrosis of subchondral bone => collapse and deformation of femoral head
Articular cartilage thickened, cleft development, fraying



Signalment
– Miniature, toy and small breeds, terriers
– 5-8 months old; range 3-13 mo
Clinical signs
– Lameness, gradual onset over 2-3 months
– Usually unilateral
– Pain on manipulation of hip
– Occasional crepitus in hip
– Atrophy of thigh muscles


Diagnosis
– X-rays

Early - Decreased bone density of epiphysis, sclerosis and thickening of femoral neck

Later- lucent areas in femoral neck

End-stage – flattening and extreme deformation of the femoral head, severe osteoarthritis

Collapse of femoral head 14 mo post-op FHO


Treatment
– Rest and analgesics
– Analgesics, anti-inflammatory drugs and cold packing 3-5 days post
– ROM exercises


Client education
– Recovery from surgery takes 3-6 months
– Glucosamines and chondroitin sulfate
– May be hereditary – do not breed
– With sx – good to excellent prognosis for full recovery
– Conservative therapy – alleviate lameness in 2-3 months in 25%


Definition of osteochondrosis
– Pathologic process in growing cartilage, primarily characterized by a disturbance of endochondral ossification that leads to excessive retention of cartilage
– Ossification is slowed, cartilage thickens, is weaker and susceptible to stress, disrupts blood supply => necrosis of bone
– Osteochondrosis dissecans - Formation of a cartilage flap over the area of bone necrosis
– Bilateral disease common
– Most commonly affected joints: shoulder, elbow, stifle, hock




Signalment: Large and giant breeds
– Great Danes, Labs, Newfoundlands, rottweilers, Bernese Mountain dogs,
Englishsetters, Old English sheepdogs
– Age: 4-8 months
Hx:
– Lameness – sudden or slowly increasing


1 or more limbs
Worse after exercise
Risk Factors:
– Diet with 3x rec levels of Ca
– Rapid growthand weight gain


PE:
– Pain on palpation or movement of affected joint
– Usually weight bearing lameness
– Joint effusion common
– Muscle atrophy if chronic
– Hock OCD- hyperextension of the tarsocrural jt




X-rays
– Flattening of subchondral bone or subchondral lucency
– Flap visualized if calcified
– Calcified bodies within the joint (joint mice)
Joint tap and analysis of synovial fluid
Arthroscopy

Great Dane humeral heads
OCD normal



Early – no flap
– Restrict activity level
– Weight control
Flap (OCD)
– Surgical removal of flap or joint mice
– Antiinflammatories
– No corticosteroids
– Chondroprotective drugs (gluocosamine, etc)


Heritibility – do not breed

DJD may develop even with surgery

Limit activity for 4-6 weeks

PT early on

Control weight

Restrict weight gain and growth in young dogs


Shoulder – good to excellent

Elbow, stifle, hock – fair to guarded





Definition: a self limiting condition affecting one or more of the long bones of young medium to large breed dogs that is characterized clinically by high density of the bone marrow cavity
Cause unknown
Painful
May be one leg or become a shifting leg lameness



Signalment
– Age – 5-18 months
– Dogs
Hx:
– No trauma
– Lameness of varying intensity
– Usually front legs but hind legs also
– Can be shifting leg lameness
– Severe: inappetance, weight loss, depression


PE
– Pain on deep palpation of long bones in affected limbs
– +/- low grade fever
– +/- muscle atrophy


Diagnostics
– X-rays: radiographic densities within the medulla of long bones

Normal density of bones
Panosteitis


Treatment
– NSAIDs- minimize pain; decrease inflammation
– Does not affect duration of disease
– Acetominophen not recommended


Client Info
– Recheck q 2 weeks
– Self-limiting disease
– Treatment symptomatic
– Multiple limb involvement
– Lameness – few days to months

Hip luxations are most common
Joint capsule must tear and ligament of femoral head must tear

Types
– Craniodorsal
 most common
 leg appears shorter
 stifle rotates outward
– Cranioventral

Usually results from unsuccessful reduction of craniodorsal luxation

Stifle rotates inward

Leg appears longer


Signs
– Hx of trauma
– Acute lameness; non wt-bearing
– Possible swelling dorsal to hip joint
– Luxated limb shorter if legs extended in
VD position


Dx
– Thumb between greater trochanter—ischial tuberosity

Rotate femur away from body
– Disparity in leg lengths
– X-ray to r/o femoral neck fracture, Legg-Perthes


Rx
– Closed reduction
 anesthesia required for proper muscle relaxation
– Using traction, rotate and pull head back in place
– Open reduction

Replace head of femur and suture soft tissue around acetabulum to keep it in place
– Either way, bandage in abduction x 2 wk (Ehmer sling)


Client info
– Px depends on:

Stability of the reduced joint

Soft tissue damage

Length of time prior to reduction of luxation
– Arthritis may occur
– Consider FHO/hip replacement if hip does not stay reduced


Less common

Difficult to reduce

 http://www.youtube.com/watch?v=P
XMRDRetmgU

Def—Diseases of muscles

Inflammatory myopathies
– Bacterial myositis (dogs and cats)

Occurs following bite wd or contamination following
Sx

Usually Staphilococcus and Clostridium spp
– Protozoal myositis

Cysts form within muscles of Toxoplasmosis-positive cats


Polymyositis—immune-mediated disease of dogs and cats
– Signs










Large breed dogs, middle-age
Weakness that gets worse with exercise
Stiff, stilted gait
Hyperesthesia on palpation
Fever, depression
Megaesophagus may develop (w/ aspiration pneumonia)
Muscle atrophy
Idiopathic
Dx—
– Elevated muscle enzymes (CPK)
– Muscle biopsy
Rx—Prednisone (2.2 mg/kg daily)


Immune-mediated Myopathies
– Masticatory muscle myositis (atrophic myositis, eosinophilic myositis)

Signs
– Involves muscles of mastication (temporalis, masseter)

These muscles have a special fiber type that has antigenic properties similar to antigenic properties of bacteria
– Muscles swelling initially
– Muscle atrophy and fibrosis
Acute Chronic

Rx—Glucocorticoids


Acquired myopathies
– Feline myopathy

Usually due to renal dysfunction and loss of K + in urine

Signs
– Cats of all ages, sexes, breeds
– Hypokalemia results in cervical ventroflexion
– Wt loss
– Periodic weakness, muscle pain

Rx—supplementation of potassium


Most bone tumors are osteosarcomas
(~100% malignant)
– Cause: unknown
– Signs (dist radius, prox humerus, dist femur, prox tibia)

Middle-age, large-breed dogs

Lameness

Wt loss

Pain, swelling of affected limb
Dx: x-rays show lysis/proliferation of new bone tissue

 http://www.youtube.com/watch?v=t
88NK39rO_o




Dx
– Biopsy for definitive diagnosis
– Thoracic radiographs to r/o metastatic disease
Rx
– Amputation of affected limb
– Chemotherapy
– Radiation therapy
– No recommended drug therapies for cats
Client info
– Bone cancer is a fatal disease
– Survival time up to 12 mo with aggressive therapy
– Biopsy is needed to confirm diagnosis
– Amputation is necessary for comfort of animal, but it doesn’t affect likelihood of metastasis or survival
– Drug therapy and follow-up lab work are expensive





Considered “inhumane” by some people
Outlawed in some European countries
San Francisco “advises” against it
It is an amputation of the last joint of cat’s toes




Reasons why owners declaw cats
– Shredded furniture, drapes
– Scratched by cat
Procedure
– Apply tourniquet to leg
– Anesthetize, remove claws
– Tight bandages x 3 d
– Send home
Do not declaw outside cat


Also banned in some European countries

Done at 2-5 days old

No anesthesia

1 stitch