A 48-year-old man with a history of diabetes presents to the emergency depament with a poorly healing right foot ulcer. The ulcer has been present for 1 month, and has never been treated. The patient denies fever or chills, and complains of mild pain at the ulcer site. His temperature is 37.6 C (99.6 F), blood pressure is 158/86 mm Hg, pulse is 94/min, and respirations are 18/min. The patient has diminished popliteal, posterior tibial, and dorsalis pedis pulses bilaterally, but the right side is worse than the left side. He has soft tissue swelling around the first toe with a 1 x 1 cm ulcer at the tip of the toe and surrounding erythema and purulent discharge. An x-ray film of the foot shows soft tissue swelling and signs of early bone destruction in the first metatarsal. What is the most likely cause of the bone destruction evidenced on the x-ray film?

Osteomyelitis is an infection of the bone that can be caused either by hematogenous spread or contiguous spread from a local focus of infection. In this case, the patient has a poorly healing ulcer in his right toe, which likely has spread to the metatarsal bone. Osteomyelitis can be caused by any microorganism, but is most often due to pyogenic bacteria or mycobacteria. Osteitis deformans is also known as Paget disease of the bone. It is an inflammatory disease of unknown etiology, characterized by abnormal and chaotic bone resorption and formation. It most commonly occurs in the spine, pelvis, skull, and long bones of the lower extremities. Osteoahritis is the most common form of ahritis. It is a chronic noninflammatory disease characterized by degeneration of aicular cailage. It is accompanied by new bone formation rather than bone destruction. Osteomalacia is due to vitamin D deficiency in adults. It is associated with defective calcification of the bone matrix. Patients can experience bone pain, which often occurs in the ribs and thighs. X-ray films show diffuse radiolucency.