Butterfly vertebra with lumbar intervertebral disc herniation

Abstract

<jats:p>A butterfly vertebra is a rare congenital anomaly that is usually asymptomatic. The authors, however, describe a novel case involving a butterfly vertebra overlapping with disc herniation that presented as radiculopathy. A butterfly vertebra is characterized by a symmetrical fusion defect resulting in a sagittal cleft vertebra. Only a few cases of butterfly vertebrae have been reported as incidental findings. This spinal anomaly may be associated with other congenital conditions such as Pfeiffer, Crouzon, Jarcho-Levin, and Alagille syndromes. Moreover, there is no previous report of a case associated with symptomatic disc herniation from the sagittal cleft.</jats:p> <jats:p>The authors excised the herniated disc fragment. They performed intraoperative discography after exposure of the corresponding intervertebral space via a conventional interlaminar approach. Histological examination of a tissue specimen showed scattered chondrocytes in the myxohyaline stroma, which indicated the nucleus pulposus.</jats:p>

Butterfly vertebra. A case report and a short review of the literature

“…The most frequent location is the lumbar spine, followed by the thoracic region [4]. As far as the authos are concerned, a sacral butterfly vertebra has been previously described only once.…”

“…Persistence of notochord explains the existence of normal disc material in the cleft, while persistence of the perichordal sheath -the absence of it. Other embryogenetic mechanisms include vascular supply defects and disordered somitogenesis [4]. Posterior displacement of the unfused segments is attributed to biomechanical instability and chronic, abnormal force transmission at the lumbosacral junction.…”

“…Progress of embryogenesis results in the appearance of 2 lateral chondrification centres at each level, which are considered to fuse between 3 rd and 6 th week, forming the cartilaginous vertebral column. Simultaneously, the notochord degenerates at the level of vertebral bodies and remains only at the intervertebral level to form the nucleus pulposus [4].…”

“…Clinical manifestations usually include chronic, periodic low back pain, usually of many years duration before diagnosis, without neurological deficits [1,4,5,16,18]. It was considered to be of low clinical importance.…”

“…The osseous parts are more frequently of equal size and non-displaced from their normal position [7]. Predominant region is the lumbar spine, followed by the thoracic region [4]. The defect is usually asymptomatic and incidentally detected or it may cause episodes of low back pain.…”