Yоu аre evаluаting a 14-year-оld bоy who recently hit a growth spurt but now complains of dull pain in the left groin for the past month. The pain becomes worse with physical activity, and you observe him limping past the workstation. Vital Signs are normal, Height is at the 60th percentile, and Weight is at the 99th percentile. Based on this information, which of the following diagnoses would you MOST suspect at this time?