雪茄征，你知道吗？

尾部退化综合征在25,000个婴儿中会有一个是这样的病症，它是婴儿脊柱下部发育不正常造成的。美国的著名艺术表演家Johnny Eck就是这样一个病例。影像学表现具有典型征象。

Radiographic features

Imaging appearances can significantly vary depending on the severity of regression. In general the following may be seen:影像学表现随退化程度不同而异。

• lumbosacral vertebral body dysgenesis/hypogenesis腰骶椎体发育不全/发育不良

• the level of atresia/dysgenesis is usually below L1 and often limited to sacrum闭锁/发育不全的水平通常低于L1和往往局限于骶骨

• truncated blunt spinal cord terminating above the expected level (wedged- or cigar-shaped conus medullaris)截断圆钝脊髓高位终止（呈楔形或雪茄形脊髓圆锥）

• severe canal narrowing rostral to last intact vertebra严重椎管狭窄端至最后一个完整椎体

Associated abnormalities may also be demonstrated (see above).

病例图片

图片来源：http://radiopaedia.org/

Caudal regression syndrome (CRS) represents a spectrum of structural defects of the caudal region. Malformations vary from isolated partial agenesis of the coccyx to lumbosacral agenesis.

Epidemiology

Caudal regression syndrome is rare, with an estimated incidence of 1:7500-100,000 7,10.

The vast majority of cases are sporadic, however familial cases occasionally occur. An association with VACTERL and Currarino triad syndromic complexes has been reported. Severe cases are usually identified in utero or at birth. Mild cases may not be identified until adulthood. There is no gender predilection.

Clinical presentation

Caudal regression syndrome may present with a broad range of symptoms:

• neurogenic bladder and anorectal malformations

• sensorimotor paresis (motor deficits > sensory deficits)

• features of sacral agenesis: narrow hips, hypoplastic gluteal muscles, shallow intergluteal cleft

• mild foot deformities and gait abnormalities

Pathology

Caudal regression syndrome results from an insult in early pregnancy (<4th week of gestation). Hyperglycaemia, infection, toxic and ischemic insults have been implicated.

Two possible aetiologies are suspected 3:

• disturbance of the primary neurulation process

• derailment of the process of degeneration and differentiation of an initially normally developed primary and secondary neural tube