This case is reported as one which illustrates the difficulty of differentiating roentgenographically between pyogenic osteomyelitis, tuberculosis, and syphilis. It furthermore offers an opportunity of correlating definite pathologic findings with an atypical radiographic appearance. Both destructive and formative types of bone lesions are present in a case proved to be tuberculosis. The case is a striking example of a predominately formative reaction in tuberculosis of bone.