OA Flashcards
Which of the following joints is most commonly affected by osteoarthritis (OA)?
A. Elbow
B. Ankle
C. First metatarsophalangeal joint (MTP)
D. Wrist
C. First metatarsophalangeal joint (MTP)
Rationale:
OA commonly affects weight-bearing joints and those subjected to significant mechanical stress. The most commonly affected joints include the hip, knee, first MTP, cervical spine, lumbosacral spine, distal interphalangeal (DIP), and proximal interphalangeal (PIP) joints in the hands, and the base of the thumb. The wrist, elbow, and ankle are typically spared, as they experience less biomechanical stress in daily activities.
Which of the following is true regarding osteoarthritis (OA) prevalence?
A. OA is equally common in men and women in all age groups.
B. OA is uncommon in individuals aged <40 years.
C. Symptomatic hip OA is more common than symptomatic knee OA.
D. Radiographic evidence of OA strongly correlates with back pain.
B. OA is uncommon in individuals aged <40 years.
Rationale:
OA prevalence increases markedly with age and is uncommon in individuals under 40 years. It becomes highly prevalent in those aged >60. Women have a higher prevalence of OA than men, particularly in middle-aged and older populations. Symptomatic knee OA is more common than hip OA, and radiographic findings of OA in the back and neck do not correlate strongly with pain in these regions.
What is the hallmark pathological change in osteoarthritis (OA)?
A. Meniscal degeneration
B. Hyaline articular cartilage loss
C. Synovitis
D. Subchondral bone sclerosis
B. Hyaline articular cartilage loss
Rationale:
The hallmark pathological change in OA is the loss of hyaline articular cartilage, which occurs in a focal and initially nonuniform manner. This cartilage loss is accompanied by other structural changes, including subchondral bone sclerosis, osteophyte formation, synovitis, and degeneration of associated structures like the meniscus in the knee. However, hyaline cartilage loss is the defining feature of joint failure in OA.
What is a common early step in the development of osteoarthritis (OA)?
A. Synovial inflammation
B. Joint injury with failure of protective mechanisms
C. Autoimmune attack on cartilage
D. Deposition of urate crystals
B. Joint injury with failure of protective mechanisms
Rationale:
A common initial step in the development of OA is joint injury that overwhelms the joint’s protective mechanisms. This leads to progressive damage, including cartilage loss, subchondral bone changes, and eventual joint failure. Synovial inflammation can occur later as a secondary process, but autoimmune or crystal deposition processes are not involved in OA’s pathogenesis.
Which of the following structural changes is least likely to occur in osteoarthritis (OA)?
A. Osteophyte formation
B. Stretching of the articular capsule
C. Synovial pannus formation
D. Meniscal degeneration in the knee
C. Synovial pannus formation
Rationale:
Synovial pannus formation is characteristic of rheumatoid arthritis (RA), not OA. In OA, structural changes include osteophyte formation, subchondral bone sclerosis, cartilage loss, stretching of the articular capsule, synovitis, and, in knees, meniscal degeneration. These changes collectively contribute to joint failure in OA.
Which of the following components provides cartilage with its tensile strength?
A. Aggrecan
B. Type 2 collagen
C. Hyaluronic acid
D. Matrix metalloproteinases (MMPs)
B. Type 2 collagen
Rationale:
Type 2 collagen is the primary macromolecule in cartilage responsible for its tensile strength. It forms a tightly woven matrix that constrains aggrecan molecules, which are responsible for compressive stiffness due to their electrostatic repulsion.
What is the primary role of synovial fluid in joint protection?
A. Providing tensile strength to the joint
B. Reducing friction between cartilage surfaces
C. Increasing compressive stiffness of cartilage
D. Serving as a barrier against enzymatic degradation
B. Reducing friction between cartilage surfaces
Rationale:
Synovial fluid reduces friction between articulating cartilage surfaces, protecting against friction-induced cartilage wear. This lubrication mechanism is essential in maintaining joint health and minimizing wear and tear.
Which of the following is true about imaging in osteoarthritis (OA)?
A. X-rays are highly correlated with the severity of OA pain.
B. Imaging is required for the diagnosis of OA.
C. Imaging is ordered only if symptoms are atypical or persistent after treatment.
D. Magnetic resonance imaging (MRI) is the gold standard for diagnosing OA.
C. Imaging is ordered only if symptoms are atypical or persistent after treatment.
Rationale:
Neither x-rays nor MRI are routinely indicated in the workup of OA. Imaging is reserved for cases where symptoms are atypical or when pain persists despite treatment. Furthermore, imaging findings correlate poorly with the presence and severity of pain in OA.
What is a characteristic feature of osteoarthritis (OA) pain progression?
A. Pain is constant from the early stages of the disease.
B. Pain starts as episodic and progresses to continuous and bothersome, even at night.
C. Pain is typically worse in the morning and improves with activity.
D. Pain is symmetrical and associated with systemic symptoms.
B. Pain starts as episodic and progresses to continuous and bothersome, even at night.
Rationale:
Early in OA, pain is episodic and often triggered by overuse of a joint, such as prolonged walking or running. As the disease progresses, pain becomes more persistent, may occur even at rest, and can interfere with sleep at night. Morning stiffness is brief (<30 minutes), distinguishing OA from inflammatory arthropathies.
Which of the following is the most appropriate first-line pharmacologic treatment for osteoarthritic pain?
A. Duloxetine
B. Intra-articular glucocorticoids
C. NSAIDs (e.g., naproxen, low-dose celecoxib)
D. Hyaluronic acid injections
C. NSAIDs (e.g., naproxen, low-dose celecoxib)
Rationale:
NSAIDs are the most commonly used medications for managing osteoarthritic pain. Among them, naproxen and low-dose celecoxib are considered safer from a cardiovascular standpoint. Intra-articular injections and duloxetine are options for cases unresponsive to NSAIDs.
Which of the following is the most potent risk factor for osteoarthritis (OA)?
A. Joint injury
B. Obesity
C. Age
D. Female gender
C. Age
Rationale:
Age is the most potent risk factor for the development of osteoarthritis. As individuals age, the risk of OA increases, with the disease becoming highly prevalent in those over 60 years of age. Although obesity and female gender also increase the risk, age remains the strongest predictor of OA’s onset and progression.
Which of the following diagnostic steps is most appropriate when evaluating a patient with suspected osteoarthritis (OA) and atypical symptoms?
A. Routine blood tests
B. Examination of synovial fluid
C. Magnetic resonance imaging (MRI)
D. X-ray of the affected joint
B. Examination of synovial fluid
Rationale:
Synovial fluid analysis is a valuable diagnostic tool when symptoms and signs suggest an inflammatory arthritis or crystal arthropathy (e.g., gout or pseudogout). A synovial fluid white blood cell count >1000/μL suggests inflammatory arthritis, gout, or pseudogout, which can be further confirmed by identifying crystals. Routine imaging (e.g., x-rays or MRI) is not indicated unless symptoms are atypical or persistent despite treatment.
What is the significance of imaging findings in the diagnosis and management of osteoarthritis (OA)?
A. Imaging is the primary method for diagnosing OA.
B. Imaging findings strongly correlate with the severity of OA pain.
C. Imaging is ordered only when symptoms are atypical or treatment is ineffective.
D. Imaging is required to confirm the diagnosis of OA.
C. Imaging is ordered only when symptoms are atypical or treatment is ineffective.
Rationale:
In OA, imaging findings such as joint space narrowing and osteophytes correlate poorly with the presence and severity of pain. Imaging (x-rays or MRI) is not routinely indicated and is reserved for cases where symptoms are not typical of OA or when pain persists despite effective treatment. Diagnosis is largely clinical, based on history and physical examination.
Which of the following is TRUE regarding acetaminophen for osteoarthritis management?
A. It is highly effective and recommended as a first-line treatment.
B. It is conditionally recommended due to limited efficacy.
C. It is associated with an increased risk of myocardial infarction.
D. It is used primarily for its anti-inflammatory properties.
B. It is conditionally recommended due to limited efficacy.
Rationale:
Acetaminophen is conditionally recommended for osteoarthritis pain management due to its limited efficacy compared to NSAIDs. It is primarily used for mild pain and does not have significant anti-inflammatory effects.
Which of the following treatments is associated with irritation of mucous membranes as a potential side effect?
A. Diclofenac 1% gel
B. Capsaicin cream
C. Hyaluronic acid injections
D. Intra-articular steroid injections
B. Capsaicin cream
Rationale:
Capsaicin cream, used topically for osteoarthritis, may cause irritation of mucous membranes as a side effect. Patients should be advised to wash their hands after application to avoid accidental contact with sensitive areas such as the eyes.
A patient with severe osteoarthritis pain is considering intra-articular injections. Which of the following statements about these treatments is most accurate?
A. Glucocorticoid injections are useful for chronic pain management with sustained effects beyond 6 months.
B. Hyaluronan injections have a well-established efficacy for all OA patients.
C. Glucocorticoid injections may alleviate pain for up to 3 months.
D. Intra-articular steroids are contraindicated in elderly patients.
C. Glucocorticoid injections may alleviate pain for up to 3 months.
Rationale:
Intra-articular glucocorticoid injections can provide relief of osteoarthritis pain for up to 3 months. However, the response is variable, and they are typically used for acute flares rather than long-term management. Hyaluronan injections have controversial efficacy and are not universally recommended.
A 65-year-old woman with advanced knee osteoarthritis reports significant pain and limited mobility despite optimal nonsurgical treatment. She is considering knee replacement surgery. What advice is most appropriate regarding surgical timing?
A. Delay surgery until the patient’s functional status has declined as much as possible.
B. Proceed with surgery now to prevent further decline in functional status.
C. Surgery is only recommended for patients with mild osteoarthritis.
D. Postoperative outcomes will be the same regardless of muscle strength.
B. Proceed with surgery now to prevent further decline in functional status.
Rationale:
Delaying surgery until substantial functional decline or muscle weakness occurs may lead to poorer postoperative outcomes. Early referral for arthroplasty can improve pain and function more effectively.
Which factor is associated with a better surgical outcome for knee or hip arthroplasty?
A. Undergoing surgery at a center performing fewer than 25 such operations annually
B. Substantial preoperative functional decline and muscle weakness
C. Early referral for surgery before severe functional impairment develops
D. Being obese at the time of surgery
C. Early referral for surgery before severe functional impairment develops
Rationale:
Early surgical intervention before severe functional decline and muscle weakness leads to better postoperative functional outcomes. Centers with higher surgical volumes and surgeons with greater experience also have better outcomes, while obesity is associated with higher failure rates.
