Nondisp fx of shaft of 1st MC bone, l hand, init for opn fx

This code signifies a break in the main body (shaft) of the first metacarpal bone (thumb) in the left hand, where the bone fragments remain in their normal alignment. This specific instance indicates that the fracture has broken through the skin, exposing the bone to the external environment.

Apply this code for initial treatment of a left thumb metacarpal shaft fracture that is documented as nondisplaced and open. This is appropriate for the first encounter where definitive treatment, such as wound debridement and fracture stabilization, is provided.

• Ensure documentation explicitly states "nondisplaced" and "open fracture" for the shaft of the first metacarpal.
• Confirm the laterality is "left hand" to avoid laterality errors.
• The "B" seventh character indicates an initial encounter for an open fracture, implying active treatment is being rendered.