A clinical diagnosis of knee osteoarthritis can be made with the following: the individual is aged 50 years or older, has activity-related joint pain, has morning stiffness that lasts <30 minutes, has crepitus on active motion, has restricted movement (will often have flexion contracture and bony enlargement and has no detectable warmth. A typical knee osteoarthritis diagnosis can be made without requiring further investigations and most often plain radiograph (x-ray) or MRI is not needed.

 

Diagnostic criteria of knee osteoarthritis is based on history, physical examination, radiographic findings and laboratory findings:

​

1. Do you have knee pain?

 

2. Are you aged over 50 years?

​

3. Do you have morning stiffness that lasts for less than 30 minutes of a morning?

 

4. Do you have crepitus on active motion- defined as any grinding, creaking, cracking, grating, crunching, or popping that occurs when moving a joint?

​

5. You have no palpable warmth of synovium- defined as your knee is not warm to the touch?

 

6. Do you have bony tenderness about the knee?

​

7. On x-ray do you have any bony enlargements or osteophytes?

 

8. On blood tests is your ESR <40mm/hour?

​

9. Is your rheumatoid factor (RF)  less than 1:40?​

​

If you answered "yes" to the majority of these questions, it is likely you have knee osteoarthritis contributing to your knee pain.