Osteoarthritis Flashcards
What is osteoarthritis (OA)?
the failure of articular cartilage and subsequent degenerative changes in subchondral bone, bony joint margins, synovium, and para-articular fibrous and muscular structures
What are the two principle changes associated with Osteoarthritis (OA)?
1) Progressive focal degeneration of articular cartilage with subsequent degeneration of surrounding soft tissue
2) Formation of new bone in the floor of the cartilage lesion at the joint margins (osteophytes).
What is the quality of pain and pain in relation to activity in OA?
Quality of pain: described as a deep ache
Pain in relation to activity: initially, pain occurs with joint use and is relieved with rest. As the disease progresses, pain occurs even without use.
When does stiffness occur in OA?
there is stiffness with initial use of the joint but it gets better unlike inflammatory arthritis.
What are Heberden nodes?
bony swellings located in the distal interphalangeal joints
What is found on the physical exam of OA?
Joint margin tenderness, fine crepitance (crackling sound made when bones rub against each other, similar to the sound of hair rubbing between your fingers), limits to motion, and enlargement of the joint due to proliferation of cartilage and bone
Does radiographic or physical examination evidence of severity reliably predict a patient’s symptoms?
No
What is primary OA?
cartilage failure an unknown cause that would predispose to osteoarthritis. It almost never affects the shoulders, elbows, ankles, metacarpophalangeal joints, or ulnar side of the wrist
What is generalized OA?
affects distal and proximal IP joints, first carpometacarpal joints, hips, knees, and spine.
What is isolated nodal OA?
affects only distal IP joints.
What is isolated hip OA?
more common in men than women
What is erosive OA?
only distal and proximal IP joints.
What is diffuse idiopathic skeletal hyperostosis?
also known as Forestier disease, occurs in men over 50, is a variant of primary osteoarthritis
What are the joints involved and the usual population affected by generalized OA?
It affects distal and proximal IP joints, first carpometacarpal joints, hips, knees, and spine of middle aged postmenopausal women
What are the joints involved, time of onset, and clinical presentation of erosive OA?
Joints involved: only distal and proximal IP joints.
Onset: symptoms begin about the time of menopause
Clinical presentation: Episodes of local inflammation, mucous cyst formation at the distal IP joint.
What are the clinical findings of erosive OA?
Bony erosions and collapse of the subchondral plate (only seen with erosive OA, not any other primary OA) with osteophytes
What is the affected population in diffuse idiopathic skeletal hyperostosis (DISH).
men over 50 years old
What is found on radiographs in DISH?
exuberant, flowing osteophytosis that connects 4 or more vertebrae with preservation of the disk space
What is the differential Dx to DISH?
distinguished from typical osteoarthritis of the spine with degenerative disk disease and from ankylosing spondylitis
What is the clinical presentation to DISH?
calcification of the pelvic ligaments, exuberant osteophytosis at the site of peripheral osteoarthritis, well-calcified bony sports at the calcaneus, and heteotropic bone formation after total join arthroplasty
What is secondary OA?
Secondary OA is cartilage failure caused by some known disorder, trauma, or abnormality. Patients are suspected of having secondary OA if they present with unusual distribution of osteoarthritis or widespread chondrocalcinosis
What are the 4 inherited disorders that are complicated by OA?
Ochronosis, hemochromatosis, Wilson disease, and acromegaly
What is the genetic defect in alkapturia?
rare autosomal recessive disorder of tyrosine metabolism. This defect leads to both alkapturia and ochronosis
What is the clinical presentation of alkapturia?
Alkapturia - excretion of large amounts of homogentisic acid in urine due to ↓ homogentistic acid oxidase. Urine darkens when allowed to stand or with sodium hydroxide.
Ochronosis – Black, oxidized, polymerized homogentistic acid pigment collects in connective tissues. Ochronotic arthritis affects the large joints (hips, knees, shoulders) and is associated with calcium pyrophosphate crystals in synovial fluid.
What are the radiographic findings in alkapturia?
calcified intervertebral disks at multiple levels is characteristic of ochronosis.
What is the genetic defect to cause hemochromatosis?
the most commonly inherited autosomal recessive disorder of white males.
What is the clinical presentation of hemochromatosis?
hepatomegaly, bronze skin pigmentation, diabetes mellitus, the consequences of pituitary insufficiency, and degenerative arthritis
What are the joints affected in hemochromatosis?
: metacarpophalangeal joints and shoulders (these joints are not affected by generalized primary osteoarthritis)
What is the genetic defect in Wilson disease?
rare autosomal recessive disorder
What is the clinical presentation of Wilson disease?
patients under 40 years old with unexplained hepatitis, cirrhosis, or movement disorder.
What is the lab abnormalities in Wilson disease?
serum level of ceruloplasmin < 200mg/L
What are the radiographic findings to wilson disease?
Differs from primary osteoarthritis in that there are more subchondral cysts, sclerosis, cortical irregularities, and radiodense lesions, which occur centrally and at the joint margins
Who are the patients at risk for neuroarthropathy (Charcot joint)?
patients with diabetes mellitus
How does a Charcot joint evolve?
Repeated microtrauma, overt trauma, small vessel occlusive disease (diabetes), and neuropathic dystrophic effects on bone contribute to neuroarthropathy
What is the clinical presentation of a Charcot joint?
Diabetic patients usually present with acute arthritic condition including swelling, erythema, and warmth in the tarsometasarsal joint of the foot. They walk with an antalgic limp and callus forms over the weight-bearing site of bony damage
What are the complications to a Charcot joint?
The callus can blister and ulcerate, allowing an infection to spread from skin to the bone. Osteomyelitis often complicates diabetic neuroarthropathy
What is the Tx of a Charcot joint?
For patients with diabetes, good local foot care, treatment of infection, and protected weight bearing
What are the risk factors for aseptic necrosis of the bone (use the acronym)?
A – alcohol, atherosclerotic vascular disease
S – steroids, sickle cell anemia, storage disease (Gaucher disease)
E – Emboli (fat, cholesterol)
P – Postradiation necrosis
T - Trauma
I - Idiopathic
C – Connective tissue disease (especially SLE), caisson disease (from path, it is the chronic form of “the bends”)
What are the joints involved with avascular necrosis?
the hips, shoulders, knees, or ankles.
What is the Tx of avascular necrosis?
conservative; use analgesics and reduce weight bearing.
What is the most sensitive test for the diagnosis of avascular necrosis?
MRI
What is the clinical presentation of hypertrophic osteoarthropathy?
: clubbing of the fingernails and painfaul distal long bone periostitis (inflammation of the periosteum).
What are the joints involved with hypertrophic osteoarthropathy?
noninflammatory arthritis at the ankles, knees, or wrists.
What are the associated conditions with hypertrophic osteoarthropathy?
primary and metastatic pulmonary malignancies, chronic pulmonary infections, cystic fibrosis, and hypoxic congenital heart disease.
What are the common radiographic findings seen in OA?
Osteophyte formation, asymmetric joint-space narrowing, subchondral bony sclerosis, and subchondral cysts
What is spondylosis?
can refer to anterolateral spinous osteophytes that come out of the vertebral body, degenerative disk disease with disk-space narrowing, or facet sclerosis
What is spondylolysis?
defect in the bony structure of the posterior neural arch (pars interarticularis, which is the weakest part of the vertebra).
What is spondylolisthesis?
bilateral spondylolysis causing the vertebra to slip forward.
What are the 3 causes of spondylolisthesis?
Trauma, osteoarthritis, and congenital.
What are the 3 therapeutic goals in OA pts?
Relieving pain, preserving joint motion and function, and preventing further injury and wear of cartilage.
What is the initial drug therapy used in the Tx of OA?
Analgesics such as acetaminophen (1g 4x/day)
What are the 4 indications for total joint arthroplasty?
1) Radiographically advanced osteoarthritis
2) Night pain that cannot be modified by changing position
3) Lockup or giving way of the weight-bearing joint associated with falls or near falls
4) Joint symptoms compromise activities of daily living
