What diagnostic code is appropriate for a closed fracture of the right ulna in a 12-year-old?

The appropriate diagnostic code for a closed fracture of the right ulna in a 12-year-old is S52.101A. This code indicates a closed fracture of the ulna, specifying the right side (indicated by the "1" after the "S52" code) and that the fracture is both closed and initial (the "A" at the end denotes it as the initial encounter for a closed fracture).

In the context of this question, while the provided answer points to a different code, understanding how these codes are structured is vital. The other codes begin with S52 but differentiate by the subsequent digits and letters. S52.001A and S52.001B refer to fractures of the non-specific ulna, rather than the closed fracture of the right ulna, which eliminates them from being suitable options for this specific situation. The presence of "B" in S52.101B indicates a subsequent encounter for the same fracture, which would not apply unless this was not the first treatment or diagnosis of the condition.

Therefore, S52.101A is indeed the most accurate representation for a closed fracture of the right ulna in a 12-year-old when considering both the side and the nature of the fracture in conjunction