尾部退化綜合征在25,000個(gè)嬰兒中會(huì)有一個(gè)是這樣的病癥，它是嬰兒脊柱下部發(fā)育不正常造成的。美國(guó)的著名藝術(shù)表演家Johnny Eck就是這樣一個(gè)病例。影像學(xué)表現(xiàn)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:影像學(xué)表現(xiàn)隨退化程度不同而異。

• lumbosacral vertebral body dysgenesis/hypogenesis腰骶椎體發(fā)育不全/發(fā)育不良

• the level of atresia/dysgenesis is usually below L1 and often limited to sacrum閉鎖/發(fā)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?cái)鄨A鈍脊髓高位終止（呈楔形或雪茄形脊髓圓錐）

• severe canal narrowing rostral to last intact vertebra嚴(yán)重椎管狹窄端至最后一個(gè)完整椎體

Associated abnormalities may also be demonstrated (see above).

病例圖片

圖片來(lái)源：http:///

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