Arthritis and OCD

Question 1

Arthorpathy

Answer 1

any joint disease

Question 2

Arthrosis

Answer 2

a joint; “wear and tear” degeneration- human term

Question 3

arthritis

Answer 3

inflammation within a joint

Question 4

polyarthritis

Answer 4

inflammation in SEVERAL joints at the same time

Question 5

osteophyte

Answer 5

forms at synovial or articular margins

Question 6

enthesiophyte

Answer 6

forms at tendon/ligament attachment

Question 7

joint mouse

Answer 7

mobile fragment within a joint; loose osteophyte; fragment of cartilage

Question 8

joint capsule

Answer 8

the sac the encloses a joint

Question 9

rrhaphy

Answer 9

to suture in place; to close

Question 10

imbrication

Answer 10

surgical tightening

Question 11

-plasty

Answer 11

surgical repair or shaping of

Question 12

Ankylosis

Answer 12

spontaneous fusion of a joint; end stage of joint disease

Question 13

arthrodesis

Answer 13

surgical fusion of a joint

Question 14

arthrotomy

Answer 14

incision into a joint

Question 15

Types of joints

Answer 15

synovial- elbow, hip, stifle, SI, veterbral facts; fibrous- skull tooth sockets; cartilaginous- symphyses, growth plates

Question 16

What is the most common classification of arthritis?

Answer 16

Secondary non-infectious

Question 17

Who gets primary non-inflammatory arthritis?

Answer 17

Hunting dogs, and CATS

Question 18

Osteoarthritis

Answer 18

Syn- OA, osteoarthrosis, DJD aberrant repair of articular cartilage- degradation of articular cartilage altered subchondral bone metabolism periarticular osteophytoisis synovial inflammation (synovitis

Question 19

How do you tell the difference between inflammatory and non-inflammatory?

Answer 19

JOINT TAP

Question 20

Answer 20

Secondary arthritis with osteophytes

Question 21

What would you see on rads for arthritis?

Answer 21

• osteophytes
• effusion
• ST swelling
• subchondral sclerosis
• increased/ decreased joint space

Remember, just because you don’t see anything on RADS, doesn’t mean it’s not there- but if you do see something then it’s there (high specificity, low sensitivity)

Correlation with clinical disease is variable

Question 22

What is the medical treatment for osteoarthritis?

Answer 22

• WEIGHT MANAGEMENT- the most important; helps with puppies to prevent/delay rad changes; adults with established OA- reduces medical need for surgery
• Excerise moderation- maintain muscle strength and joint flexibility wihout increasing pain
• physical rehabiliation therapy- passive ROM
• sympton- moderifying agents (analgesics and NSAIDS)
• disease-modifiying agents (reparative)
• Nutraceuticals

Question 23

What is the most effective non-surgical treatment for OA?

Answer 23

WEIGHT MANAGMENT

Question 24

NSAIDS for OA

Answer 24

NSAIDs reduce pro-inflammatory mediators by inhibiting cyclooxygenase

COX-1 inhibition: GI, renal side effects

COX-1 sparing or COX-2 selective drugs may also cause GI, renal or hepatic problems

All have side effects Cats – glucuronidation Onsior (robenacoxib)

Question 25

Disease-Modifying Agents

Answer 25

Promote synthesis over breakdown Building blocks of articular cartilage or fluid Polysulfated glycosaminoglycan (PS-GAG) Adequan label recommends IM injection (SQ) Pentosan polysulfate – interstitial cystitis Hyaluronic acid – synovial fluid Good EBM support for PS-GAG and PPS Heparin analogues

Question 26

Neutraceuticals

Answer 26

Food or part of a food that provides medical benefit Cartilage building blocks Anti-inflammatory effects Glucosamine/chondroitin Omega-3 fatty acids Avocado and soybean unsaponifiables Others

Question 27

Omega-3 Fatty Acids

Answer 27

Eicosapentanoic acid (EPA) Docosahexanoic acid (DHA) Compete with arachidonic acid (AA, O-6 FA) as a substrate for COX Produce less proinflammatory mediators May decrease need for NSAIDS Rarely cause GI problems EBM – good\*

Question 28

Avocado/Soybean ASUs

Answer 28

Avocado and soybean oil unsaponifiables Dasuquin Anti-inflammatory, anti-osteoarthritic Decrease inflammatory mediators Increase cartilage matrix synthesis Based upon in vitro models Experimentally protective

Question 29

Autologous Platelet Therapy

Answer 29

Platelets collected and injected into involved joint JAVMA November 2013: Pain and weight bearing improved at 12 weeks Mechanism unknown Some debate over

Question 30

Stem Cell Therapy

Answer 30

Lots of studies in horses and humans EBM very iffy in dogs for clinical arthritis May be appropriate for some cases Non-responsive immune-mediated disease When salvage or replacement is not viable Less expensive than joint replacement(?) Not wholly benign – requires anesthesia

Question 31

which Cox receptor do you only want to block?

Answer 31

COX-1

Question 32

Surgical Treatment – Salvage

Answer 32

Indicated when severe DJD is present Generally delayed as long as possible Goal: preserve life/limb function No attempt to cure or fix cause of DJD Outcome keyed to procedure/technique rather than cause Joint replacement arthroplasty Partial joint excision arthroplasty Arthrodesis (also technically an arthroplasty) Amputation (NOT an arthroplasty)

Question 33

What joints can you do a joint replacement arthroplasty with?

Answer 33

HIP, STIFLE, ELBOW, SHOULDER

Question 34

What are the principles of arthrodesis?

Answer 34

* complete removal of all articular cartilage * cancellous bone graft * rigid fixation (usually DCP) * fusion at a standing angle

Question 35

Definition of OCD

Answer 35

* defect in endochrondral ossificaiton * endochondral ossification: the process by which epiphyseal cartilage becomes bone * starts from the epihyseal center of ossification * travels outward- "ossification wave"

Question 36

Endochondral ossification

Answer 36

* cartilage blood supply: perichondral plexus * ossification wave- anastomoses form * perichondral plexus * epihyseal bone supply

Question 37

What is the pathophysiology of OCD(osteochrondritis dissecans)?

Answer 37

* Disruptions in anastomoses lead to cartilage necrosis * necrosis of cartilage "blocks" ossification wave(like objects in a light beam) * necrotic epiphyseal cartilage cannot ossify * this is what is meant by "failure of ossification" * small defects may ossify by other means * "intramembranous ossification" * lesion resolves- not a clinicial problem * Failure to ossify- thickened cartilage * thickened cartilage acts as "stress riser" * necrosis- cleft between cartilage and bone * focused stresses over cleft- fracture of cartilage

Question 38

where does 80% of long bone growth come from?

Answer 38

physis

Question 39

When does endochondral ossificaiton occur?

Answer 39

6 months

Question 40

Osteochondritis Dissecans

Answer 40

Osteochondrosis vs. Osteochondritis Necrotic cartilage induces repair Inflammation is the first stage of repair Defect in joint surface accelerates DJD Pain of clinical disease Initially: result of inflammation due to necrosis Later: result of degenerative joint disease This is the basis of the “biphasic presentation”

Question 41

Etiology of OCD

Answer 41

Genetics/heredity Nongenetic/environmental factors Nutrition Vitamin D/Calcium Energy Trauma Both genetic and nongenetic factors must be present for disease to manifest Genes alone not responsible for disease Genes dictate susceptibility to other factors Gender – males predisposed Breed – large, giant breeds Heritability 10-45% DON’T BREED Vitamin D and Calcium High Ca/Vit D promotes errors in endochondral ossification in great danes Direct causation of OCD not established High Ca/Vit D linked to other ortho diseases Energy Promotes development of bone and muscle Increases stress on developing cartilage Microtrauma – normal weightbearing stress Abnormal cartilage more prone to injury Lesions occur even with normal stresses Macrotrauma – athletic, high-impact stress May cause subclinical to become clinical No direct evidence in dogs Shown to be a factor in human OCD

Question 42

What is the most common trauma that causes OCD?

Answer 42

microtrauma

Question 43

What is the typical signalment of OCD?

Answer 43

male large/giant breed dog

Question 44

What are the most common joints affected with OCD?

Answer 44

Shoulder – caudolateral humeral head Elbow – medial humeral condyle Hock – medial or lateral talar ridge Stifle – medial or lateral femoral condyle

Question 45

Answer 45

OCD- flattened caudal humeral head

Question 46

What are preventive measures for OCD?

Answer 46

Preventive measures (i.e., no clinical signs) Diet: energy, calcium, vitamin D restriction Exercise restriction Evidence – dogs vs. humans Difficulty – confinement vs. eliminating high-impact

Question 47

Indications and treatment for conservative OCD Lesions

Answer 47

Indications Small lesion Young patient (ossification incomplete \< 6 mos) Clinically silent or mild lameness Poor surgical outcome – site-dependent Diet/exercise restriction Weight control +/- NSAID or other therapies

Question 48

Surgical Treatment for OCD

Answer 48

Fragment removal and subchondral bone debridement – usually arthroscopic Replacement of articular cartilage with fibrocartilage – imperfect Osteochondral transplants (OATS) Various synthetic/semisynthetic implants in humans