**Question:** Transient synovitis {toxic synovitis} of the hip is characterized by all of the following, except -

A. Pain in the hip joint
B. Reduced range of motion in the hip joint
C. Decreased joint effusion
D. Radiographic abnormalities

**Core Concept:**
Transient synovitis of the hip is a self-limiting inflammatory condition affecting the hip joint, often seen in children and adolescents. It is characterized by pain, swelling, and inflammation of the synovial membrane lining the joint, leading to symptoms such as pain, reduced range of motion, and increased joint effusion (fluid accumulation). Radiographic abnormalities can be seen in other conditions, not specifically associated with transient synovitis.

**Why the Correct Answer is Right:**
The correct answer, **D. Radiographic abnormalities**, is right because transient synovitis does not usually cause significant joint effusion or radiographic changes, such as bone erosions or joint space narrowing. These findings are typically seen in more severe conditions like septic arthritis or avascular necrosis.

**Why Each Wrong Option is Incorrect:**

**A. Pain in the hip joint**: Pain is a key feature of transient synovitis, as it is an inflammatory condition causing irritation and inflammation in the synovial membrane lining the joint.

**B. Reduced range of motion in the hip joint**: Reduced range of motion is a common symptom in transient synovitis due to the inflammation and pain affecting the joint's mobility.

**C. Decreased joint effusion**: Joint effusion is increased in transient synovitis, not decreased. The swelling and inflammation lead to increased joint fluid, causing joint effusion, which is a typical sign of this condition.

**Clinical Pearl:**
Transient synovitis should be considered in patients presenting with acute onset hip pain, especially in pediatric patients. While radiographic abnormalities are not specific to transient synovitis, pain and reduced range of motion are essential features to identify the condition.