Knee pain can be a result of many possible causes and osteopaths are trained to screen and assess to try and determine the most likely of diagnoses.

Here are a list of possible causes that would be considered depending upon the presentation symptoms. 
• Osteoarthritis
• Referred hip pain
• Patellofemoral tracking problems
• ITB Syndrome
• Gout
• Reiter’s Syndrome
• Rheumatoid Arthritis
• Pseudogout
• Septic Arthritis
• Trauma / Injury (e.g. ACL Rupture, meniscal tear)
• Infection
• Patellar tendonitis (Jumpers knee)
• Growth Spurts in active young people (Oshgood Schlaters)

Here are risk factors and red flags that I would enquire upon in my case history:
• History of arthritis
• Exercise
• Injury
• Gout 
• Acute locking
• Severe swelling
• Giving way
• Pain at night
• Inability to bear weight
• Uncontrollable pain
• Hot and swollen joint (possible sepsis)
• Mass or swelling
• Onset coincides fever, night sweats, weight loss, general malaise
• Trauma / injury that may have caused fracture or dislocation

If you are experiencing any of the symptoms discussed, please seek medical attention immediately.