Joint not involved in osteoahritis is
**Joint not involved in osteoarthritis is**
**D. DIP joint (Distal Interphalangeal joint)**
**Core Concept**
Osteoarthritis (OA) is a degenerative joint disease characterized by progressive wear and tear of articular cartilage, leading to joint pain and stiffness. The disease commonly affects weight-bearing joints such as the hips, knees, and spine, as well as joints subjected to repetitive stress like the hands.
**Why the Correct Answer is Right**
The distal interphalangeal (DIP) joint is the joint between the distal phalanx and the base of the next distal phalanx in the fingers. Osteoarthritis typically spares the DIP joints, as they are subjected to relatively low stress and are more resistant to degenerative changes. In contrast, the proximal interphalangeal (PIP) joints and the first carpometacarpal (CMC) joint in the thumb are commonly affected in osteoarthritis.
**Why Each Wrong Option is Incorrect**
* **Option A:** Typically involved in osteoarthritis, especially in individuals with a history of repetitive trauma or abnormal joint mechanics.
* **Option B:** Commonly affected in osteoarthritis, particularly in individuals with a history of rheumatoid arthritis or other inflammatory arthritis.
* **Option C:** Frequently involved in osteoarthritis, especially in individuals with a history of repetitive hand use or trauma.
**Clinical Pearl / High-Yield Fact**
Remember the "HOPE" joints in osteoarthritis: Hips, Osteoarthritis of the knees, PIP (Proximal Interphalangeal) joints, and Elbow (involvement is less common but can occur).