Mohammad Mohammad, Al-Kahtani F S
Division of Plastic Surgery at King Saud University and King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia.
World J Plast Surg. 2019 Jan;8(1):112-115. doi: 10.29252/wjps.8.1.112.
Dorsal dimelia (the appearance of dorsal hand structures on the palmar aspect of the hand) and ventral dimelia (the appearance of ventral hand structures on the dorsal aspect of the hand) are rare congenital anomalies of the hand. None of the previously reported cases had combined dorsal and ventral dimelia in the same patient. Here, we report a case of severe ulnar ray deficiency. The hand had two digits: the radial digit had a palmar nail (dorsal dimelia) and the ulnar digit had absence of the normal dorsal nail along with the appearance of an ectopic pulp on the dorsal aspect of the digit (ventral dimelia). Ulnar ray deficiency is an error of sonic hedgehog (SHH) responsible for antero-posterior patterning of the limb in-utero. Ventral and dorsal dimelia are errors of dorso-ventral patterning of the hand. The complex interactions of SHH with the dorso-ventral axis of development may explain the concurrent dimelia in our patient.
背侧并指畸形（手掌侧出现手背结构）和腹侧并指畸形（手背后侧出现手掌结构）是罕见的手部先天性畸形。既往报道的病例中，没有同一患者同时合并背侧和腹侧并指畸形的情况。在此，我们报告一例严重尺侧射线发育不全的病例。该手有两个手指：桡侧手指有掌侧指甲（背侧并指畸形），尺侧手指正常背侧指甲缺失，且在手指背侧出现异位指腹（腹侧并指畸形）。尺侧射线发育不全是由 Sonic hedgehog（SHH）基因异常引起的，该基因负责子宫内肢体的前后模式形成。腹侧和背侧并指畸形是手部背腹模式形成的异常。SHH 与背腹发育轴的复杂相互作用可能解释了我们患者中同时出现的并指畸形。
