I cannot make a definite diagnosis from a photographed X-ray screen, but the abnormality appears to be a small lytic (darker) lesion in the distal left tibia, just above the ankle joint.

Its visible appearance is more consistent with a geographic, non-aggressive-appearing bone lesion than an obvious destructive malignancy: I do not see a clear pathologic fracture, dramatic periosteal reaction, or large soft-tissue mass in this image. A common benign possibility, especially in children, adolescents, and young adults, is a non-ossifying fibroma / fibrous cortical defect. Other possibilities depend heavily on your age, exact symptoms, and the original full-resolution images.

It is not possible to confirm the exact lesion type from this single low-resolution photograph. The appropriate next step is the official radiology report and review by an orthopaedic surgeon, ideally an orthopaedic oncology or musculoskeletal specialist if the lesion is indeterminate. For an indeterminate lesion seen on radiographs, MRI is commonly used to characterize it and evaluate marrow or soft-tissue involvement, consistent with the ACR bone-tumor imaging guidance.

Seek urgent assessment if there is severe or escalating pain, pain at rest/night, fever, inability to bear weight, a recent injury with sudden pain, swelling, or numbness.

If you share the written X-ray report, your age, and whether there is pain or prior injury, I can help translate what it means.