Which of the following is not included in Altman's criteria for diagnosing knee osteoarthritis?

• A. Pain with prolonged sitting > 30 minutes
• B. Age greater than 50
• C. Morning stiffness lasting less than 30 minutes
• D. Presence of crepitus during knee motion

Answer: (A)

The criteria for diagnosing knee osteoarthritis as per Altman's guidelines are aimed at identifying the presence of specific clinical features consistent with the disease. Among these criteria, one significant factor is the presence of classic symptoms such as age, morning stiffness, and crepitus.

When considering the symptom of pain with prolonged sitting greater than 30 minutes, it is important to note that although this symptom can be associated with knee osteoarthritis, it is not part of Altman's formal criteria. Instead, Altman's criteria focus on more established symptoms that include age over 50 years, a specific duration of morning stiffness (less than 30 minutes), and the presence of crepitus during movement.

The relevance of age confirms the higher prevalence of osteoarthritis in older individuals, while the stipulation of morning stiffness lasting less than 30 minutes helps differentiate it from other types of arthritis, such as rheumatoid arthritis, which typically presents with longer-lasting stiffness. The presence of crepitus during knee motion indicates the characteristic joint changes associated with osteoarthritis, further supporting the diagnosis.

Therefore, pain with prolonged sitting, while a valid and relatable symptom in patients with knee osteoarthritis, does not form part of the structured diagnostic criteria established by Altman, emphasizing why it is the item