Describe typical signs of TMJ osteoarthritis on examination.

• A. Joint crepitus, tenderness over the TMJ, reduced range of motion, jaw deviation on opening, and sometimes malocclusion or trismus
• B. Pain with neck movement only
• C. Normal range of motion and no tenderness
• D. Swelling of the cheeks without jaw involvement

Answer: (A)

TMJ osteoarthritis typically presents with degenerative changes in the joint that create mechanical symptoms you can detect on examination. The most common signs are crepitus in the joint when the jaw is moved, reflecting roughened articular surfaces and possible disc–condyle impingement. Tenderness over the TMJ indicates inflammatory or degenerative changes in the joint tissues. A reduced range of motion is often observed because pain and structural wear limit how far the jaw can open and move. When opening, the jaw may deviate toward the side with greater involvement due to unequal mobility of the condyles. Over time, changes in the joint can alter how the teeth meet, leading to malocclusion, and in some cases the opening can be limited further by muscle guarding or a trismus-like pattern.

These signs fit TMJ OA well because they combine joint-specific findings (crepitus, tenderness directly over the TMJ) with functional consequences (reduced motion, deviation on opening, potential malocclusion or limited opening). Choices describing neck-only pain, normal motion with no tenderness, or cheek swelling without jaw involvement don’t reflect the localized, movement-related and mechanical features expected in TMJ osteoarthritis.