Radiograph showing a<unk>  A<unk> ,<unk>  finger, or<unk>  rib is a rare congenital abnormality in humans, in which bone tissue develops in the soft tissue near the<unk> , resembling a rib or finger and often divided into one or more segments with pseudo-articulations.<unk> s are typically benign and asymptomatic, and are usually discovered accidentally. Approximately 41 cases have been reported. The<unk>  was first reported by D. Sullivan and W.S. Cornwell in 1974.<unk> s may be located at any level of the<unk> , the lower ribs, or even the anterior abdominal wall. It is theorized that<unk>  anomalies arise during the mesenchymal stage of bone growth, within the first six weeks of embryogenesis. Their formation may result from a failure of the primordium of the coccyx to fuse to the vertebral column, leading to the independent development of a proto-rib structure.
Pelvic digit
Ulnar claw
Jaipur foot
Seal finger
Scalpel
Nintendo thumb
Abductor wedge
Armstrong limit