Finger retronychias detected early by 3D ultrasound examination

Abstract

Background A new pattern of ingrown nail, called retronychia is involved in the posterior translation of the whole nail unit producing paronychia. Objective To demonstrate an unusual case of paronychia that affected three of the fingers on the right hand. Methods We used 3D ultrasound to study the whole nail unit in the fingers of both the affected (right) and non affected (left) hand. Results Backward motion of the nail unit with decreased distance between the origin of the nail plates and the distal interphalangeal joint was clearly demonstrated by 3D ultrasound in the affected fingers. Conclusion 3D ultrasound provides non invasive and more understandable information about the physiopathological changes in retronychia.