In the case of a high-school athlete with a positive fat-pad sign, which tissue likely required protection during immobilization?

• A. Distal radius
• B. Trochlea
• C. Ulna
• D. Humeral head

Answer: (B)

The presence of a positive fat-pad sign is indicative of intra-articular bleeding or swelling, particularly in the context of elbow injuries. When a high-school athlete exhibits this sign, it typically suggests that the joint capsule is affected, commonly through a subtle fracture or injury to structures around the elbow joint, especially in the area around the trochlea, which is the part of the humerus that interacts with the ulna during elbow flexion and extension.

During immobilization, it is crucial to protect the trochlea because it serves as a key articulation point that allows for the proper function of the elbow, and any associated injuries can lead to complications such as stiffness, instability, and impaired motion if not adequately managed. Protecting the trochlea during the healing process is essential to ensure proper joint alignment and function.

While the other options, such as the distal radius, ulna, and humeral head, are important structures in the upper limb, they do not directly correlate with the positive fat-pad sign in this specific scenario. The emphasis on the trochlea highlights the importance of identifying and protecting the exact structures involved in the elbow joint pathology.