**Core Concept**
A Hill-Sach's lesion is a bony defect in the posterolateral aspect of the humeral head, resulting from recurrent posterior dislocation of the shoulder joint. This lesion is caused by the head of the humerus impacting against the anterior edge of the glenoid fossa during dislocation.

**Why the Correct Answer is Right**
The Hill-Sach's lesion is located in the posterolateral aspect of the humeral head due to the specific mechanism of injury. When the humerus dislocates posteriorly, the head of the humerus strikes against the anterior edge of the glenoid fossa, causing a compression fracture. This results in a bony defect in the posterolateral aspect of the humeral head. The posterolateral location is due to the anatomy of the shoulder joint and the direction of the dislocation force.

**Why Each Wrong Option is Incorrect**
**Option A:** The anteromedial aspect of the humeral head would not be affected by a posterior dislocation, as the dislocation force is directed posteriorly.
**Option B:** The superior aspect of the humeral head is not typically involved in a Hill-Sach's lesion, as the injury is related to the impact against the glenoid fossa.
**Option C:** The medial aspect of the humeral head is not typically involved in a Hill-Sach's lesion, as the injury is related to the impact against the glenoid fossa.

**Clinical Pearl / High-Yield Fact**
A Hill-Sach's lesion is a characteristic finding in patients with recurrent posterior dislocation of the shoulder joint and is often used as a diagnostic clue in the evaluation of shoulder instability.

**Correct Answer:** C.