Type of Article:  Original Research

Volume 5; Issue 4.1 (October 2017)

Page No.: 4492-4499

DOI: https://dx.doi.org/10.16965/ijar.2017.382


Subhra Mandal *1, Moumita Saha 2, Shirshendu Ganguly 3, Manjari Chatterjee 4, Prabir Mandal 5, Ramprasad Saha 6.

*1 Associate Professor, Department of Anatomy, Medical College, Kolkata, West Bengal, India.

2 Senior Resident, Anatomy, R.G. Kar Medical College, Kolkata, West Bengal, India.

3 Demonstrator, Anatomy, Medical College, Kolkata, West Bengal, India.

4 Retired Professor and Head, Department of Anatomy, Medical College, Kolkata, West Bengal, India.

5 Medical Officer, Bangur Hospital, Kolkata, West Bengal, India.

6 Final Year M.D. P.G.T. (Paediatrics), R.G. Kar Medical College, Kolkata, West Bengal, India.

Address for Correspondence: Dr.(Mrs) Subhra Mandal, Associate Professor, Department  of Anatomy, Medical College & Hospital, Kolkata, West Bengal, India. Cont No.- 9477458100/9830814744 E-Mail: drsuvramandal@gmail.com


Introduction: The caudal epidural anaesthesia or block (CEB) is a process where special medications are injected into epidural space to provide analgesia and anaesthesia in various clinical procedures.CEB has been widely used for the treatment of lumbar spinal disorders, conservative management of chronic back pain as well as for providing anaesthesia in obstetrics .Successful CEB depends on precise localisation of sacral hiatus (SH),through which we gain access to sacral epidural space for effective block of sacral nerves. Anatomically sacral hiatus indicates termination of sacral canal resulting from failure of fusion of lamina of 5th sacral vertebra. It is utmost essential to have clear concept about anatomical variations associated with sacral hiatus so that success of CEB is guaranteed.

Aim: To study the morphometry of sacral hiatus as well as anatomical variations related to it that is useful for successful caudal epidural block.

Materials and methods: Present study was carried out on 191 dry human sacra (West Bengal, Indian population) to record various anatomical landmarks of sacral hiatus.

Result: Various shapes of sacral hiatus were recorded which included-Inverted U (46.84%) , Inverted V(38.42%),Irregular(11.58%),Dumb-bell(3.16%) and Agenesis of SH(1case). The Apex of sacral hiatus was most commonly found at the level of 4th sacral vertebra in 60% specimens and base of SH was present opposite the body of 5th sacral vertebra in 76.32% cases .Also, 82.63% specimen had mean length of sacral hiatus in between1to 2 cm. The anteroposterior diameter of sacral canal measured at the apex of SH was 0.4 to 0.6 cm in 68.95% cases .The width at the base of sacral hiatus most commonly (80.52%) ranged between more than1 to 2 cm in our study.

Conclusion: Acknowledging the broad spectrum of clinical implications of caudal epidural block,it’s very important to identify the precise location of sacral hiatus and caudal epidural space. Discrepancies in size and shape of SH, neighbouring bony irregularities and occasional defects in the dorsal wall of sacral canal should be thoroughly considered before performing CEB ,so that inadvertent dural sac puncture is avoided and surrounding essential structures are not injured. Instead of using conventional blind technique, newer fluoroscopy or ultrasound guided needle placement has markedly improved the success rate of CEB.

Key words: Sacral hiatus (SH), Caudal epidural block (CEB), Sacral canal, Dural sac, Fluoroscopy.


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Cite this article: Subhra Mandal, Moumita Saha, Shirshendu Ganguly, Manjari Chatterjee, Prabir Mandal, Ramprasad Saha. UNRAVELLING THE MYSTERY BEHIND SUCCESSFUL CAUDAL-EPIDURAL BLOCK. Int J Anat Res 2017;5(4.1):4492-4499. DOI: 10.16965/ijar.2017.382