Which type of ankle sprain is associated with severe pain and marked instability?

Which type of ankle sprain is associated with severe pain and marked instability?

• A. Grade I lateral ankle sprain.
• B. Grade II lateral ankle sprain.
• C. Grade III lateral ankle sprain.
• D. Medial ankle sprain.

Answer: (C)

Ankle sprains are graded by how much the ligaments are torn, and this directly tracks with pain, swelling, and instability. A complete rupture of the lateral ligaments (the ATFL, often with the CFL) is a Grade III sprain. When those ligaments are fully torn, the ankle loses its stability, producing severe pain, significant swelling, and a noticeable “giving way” feeling with marked laxity on exam. This combination—severe pain plus clear instability—is the hallmark of a Grade III lateral ankle sprain. By contrast, Grade I is a simple stretch with minimal swelling and no instability, Grade II is a partial tear with some laxity but not the pronounced instability seen with a full rupture, and a medial sprain involves the deltoid ligament and, while potentially serious, doesn’t typically present with the same pattern of severe pain and marked instability as a complete lateral tear.

Ankle sprains are graded by how much the ligaments are torn, and this directly tracks with pain, swelling, and instability. A complete rupture of the lateral ligaments (the ATFL, often with the CFL) is a Grade III sprain. When those ligaments are fully torn, the ankle loses its stability, producing severe pain, significant swelling, and a noticeable “giving way” feeling with marked laxity on exam. This combination—severe pain plus clear instability—is the hallmark of a Grade III lateral ankle sprain.

By contrast, Grade I is a simple stretch with minimal swelling and no instability, Grade II is a partial tear with some laxity but not the pronounced instability seen with a full rupture, and a medial sprain involves the deltoid ligament and, while potentially serious, doesn’t typically present with the same pattern of severe pain and marked instability as a complete lateral tear.