Sacralization of Fifth Lumbar Vertebra- A Case Report

Case Report

Austin J Anat. 2017; 4(2): 1066.

Sacralization of Fifth Lumbar Vertebra- A Case Report

Shetty AS1 and Jetti R2*

1Department of Anatomy, Yenepoya Medical College, Yenepoya University, India

2Department of Basic Medical Sciences, College of Applied Medical Sciences, King Khalid University, Saudi Arabia

*Corresponding author: Jetti R, Department of Basic Medical Sciences, College of Applied Medical Sciences, King Khalid University, Guraiger-3665, Saudi Arabia

Received: January 27, 2017; Accepted: February 16, 2017; Published: February 20, 2017

Abstract

During the osteology demonstration session for medical undergraduate students, we have observed a sacrum with sacralisation of fifth lumbar vertebra. The sacrum had six vertebrae with five pelvic sacral foramina. The body of fifth lumbar vertebra was completely fused with first sacral vertebra. The transverse process on the right side was broad and totally fused with ala of sacrum, whereas left side transverse process was not fused with ala. On the posterior aspect, the inferior articular facets of fifth lumbar vertebra were fused with superior articular facets of first sacral vertebra. From this observation, we conclude that, this is a unilateral sacralisation of fifth lumbar vertebra. Since sacralisation is strongly associated with low back pain, the present case is of high clinical value for medical personnel.

Keywords: Sacrum; Sacralisation; Lumbarisation; Lumbosacral transition vertebra

Introduction

The lumbosacral spine transmits the upper body weight to the lower limbs, thus plays a vital role in posture. Anatomical variations of lumbosacral region include change in the number of sacral vertebrae by fusion of fifth lumbar vertebra or first coccygeal vertebra or deletion of first sacral vertebra [1]. Lumbosacral transitional vertebrae are congenital anomalies of lumbosacral spine, which includes sacralisation of fifth lumbar vertebra or lumbarisation of first sacral vertebra. The incidence ratio of sacralisation to lumbarisation was reported as 2:1 [2]. Sacralisation is classified in to bilateral and unilateral, in bilateral there is a bony fusion between transverse process of fifth lumbar and sacrum on both sides; whereas unilateral the fusion is on either right or left side only. It is also classified into complete and incomplete; in complete sacralisation there is complete bony fusion between the abnormal transverse process and sacrum. In case of incomplete sacralisation there will be a well-defined joint line between the transverse process and sacrum [3]. In case of lumbarisation the first sacral vertebra fails to fuse with second one the individual appears to have six lumbar vertebrae. On the other hand, in sacralisation the last lumbar vertebra fuses with first sacral vertebra the person appears to have four lumbar vertebras [4].

Bertolotti is the first one to report sacralisation, in which the transverse process of fifth lumbar vertebra is large and fused with sacrum or ilium or both. This is observed in 3.6% to 18% of the population [5].

Case Presentation

During the osteology demonstration session of sacrum for medical undergraduate students, we have noticed a sacrum with sacralisation of fifth lumbar vertebra. The sacrum belongs to adult male; the precise age was unknown.

On examination of anterior view of sacrum, it had six vertebrae with five pelvic sacral foramina, the last lumbar vertebral body was fused with the first sacral vertebra. The transverse process on right side was large and fused with the ala of the sacrum. However transverse process on left side was usual size and did not fuse with the ala of sacrum (Figure 1). On posterior view of sacrum, the inferior articular facets of fifth lumbar vertebra were fused with superior articular facets of first sacral vertebra (Figure 2). All the other features of the sacrum was normal.

Citation: Shetty AS and Jetti R. Sacralization of Fifth Lumbar Vertebra- A Case Report. Austin J Anat. 2017; 4(2): 1066. ISSN:2381-8921