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A 65-year-old man comes to his primary care provider for evaluation of pain in both knees. His symptoms worsen with activity and improve with rest and ibuprofen. The patient had previously been an avid runner but had to stop due to the joint pain. Past medical history is notable for hypertension and a right fibular fracture, which occurred after a biking accident. Vitals are within normal limits. Examination of the affected joints reveals crepitus and mildly reduced range of motion. The remainder of the patient’s physical examination is noncontributory. Knee imaging is ordered, and the results are as follows:

Reproduced from: Radiopedia

Which of the following additional findings, if present, would best support the patient’s diagnosis?

External References

First Aid








Acetaminophen p. 498

for osteoarthritis p. 476


osteoarthritis p. 476

Nonsteroidal anti-inflammatory drugs (NSAIDs) p. 499

osteoarthritis p. 476


osteoarthritis/rheumatoid arthritis p. 476

Osteoarthritis p. 476

celecoxib for p. 499

presentation p. 718


Content Reviewers

Osteo- means “bone”, and -arth- refers to “arthron” which means joint, and -itis means “inflammation”, so osteoarthritis is a disease involving inflammation of the bone and joint cartilage.

It was once thought that the “itis” part of osteoarthritis was a misnomer, and that inflammation didn’t play a role in its development, and that it was mostly a degenerative disease resulting from simple “wear and tear”.

Nowadays, it’s thought that inflammation does indeed play an important role in the development of osteoarthritis.

Alright, so a healthy joint consists of two bones, each with its own layer of articular cartilage, which is a type of connective tissue that allows the two bones to glide against each other essentially without friction.

With Osteoarthritis, we’re really talking about one particular kind of joint which is a synovial joint.

Along with articular cartilage, another important component of synovial joints, and where they get their name from, is the synovium, which along with the surface of the articular cartilage, forms the inner lining of the joint space.

The synovium’s composed of loose connective tissue, blood vessels, lymphatic vessels, and on the surface—”Type A” cells that clear cellular debris and “Type B” cells that produce components of synovial fluid, which helps lubricate the two articular surfaces.

One of the main issues in osteoarthritis is the progressive loss of this articular cartilage, which means there’s not much separating the two bones anymore, which adds a significant amount of friction between them, which then generates inflammation, and triggers pain through the nerve endings in this joint space.

Maintaining healthy articular cartilage is the chondrocyte’s job, a specialized cell responsible for maintaining everything cartilage-related.


Osteoarthritis is a degenerative joint disease usually caused by age-related breakdown of joint cartilage and underlying bone. This leads to stiffness and pain in weight-bearing joints that worsens with activity and improves with rest. Other symptoms of osteoarthritis include a grinding sensation when the joint is moved, and difficulty moving the affected joint. Risk factors for developing osteoarthritis include advancing age, obesity, and joint injury. Treatment involves losing weight, moderate exercise, physical therapy, and drugs to reduce pain and inflammation.


  1. "Robbins Basic Pathology" Elsevier (2017)
  2. "Harrison's Principles of Internal Medicine, Twentieth Edition (Vol.1 & Vol.2)" McGraw-Hill Education / Medical (2018)
  3. "Pathophysiology of Disease: An Introduction to Clinical Medicine 8E" McGraw-Hill Education / Medical (2018)
  4. "CURRENT Medical Diagnosis and Treatment 2020" McGraw-Hill Education / Medical (2019)
  5. "Osteoarthritis" The Lancet (2015)
  6. "OARSI guidelines for the non-surgical management of knee osteoarthritis" Osteoarthritis and Cartilage (2014)
  7. "The Mechanobiology of Articular Cartilage: Bearing the Burden of Osteoarthritis" Current Rheumatology Reports (2014)

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