Caudal Epidural Block: An Updated Review of Anatomy and Techniques

Abstract

Caudal epidural block is a commonly used technique for surgical anesthesia in children and chronic pain management in adults. It is performed by inserting a needle through the sacral hiatus to gain entrance into the sacral epidural space. Using conventional blind technique, the failure rate of caudal epidural block in adults is high even in experienced hands. This high failure rate could be attributed to anatomic variations that make locating sacral hiatus difficult. With the advent of fluoroscopy and ultrasound in guiding needle placement, the success rate of caudal epidural block has been markedly improved. Although fluoroscopy is still considered the gold standard when performing caudal epidural injection, ultrasonography has been demonstrated to be highly effective in accurately guiding the needle entering the caudal epidural space and produce comparative treatment outcome as fluoroscopy. Except intravascular and intrathecal injection, ultrasonography could be as effective as fluoroscopy in preventing complications during caudal epidural injection. The relevant anatomy and techniques in performing the caudal epidural block will be briefly reviewed in this article.

A simple approach for ultrasound-guided pararadicular injections in the sacral spine: a pilot computer tomography controlled cadaver study

“…Nikooseresht et al [13] and Kim et al [14] presented in a similar setting that ultrasound can be used as a screening tool for performing caudal epidural injections. Quite recently Kao et al demonstrated in their review article relevant anatomic features and variations of the sacral bone and the development of imaging guided techniques, also including the US-guided approach for performing caudal epidural injections [15], They used a longitudinal transducer position with the sacrococcygeal ligament as the sighted landmark. The presence of unidirectional flow in the color Doppler was defined as a successful caudal epidural injection [16] To the best of our knowledge this is the first study to evaluate the feasibility and accuracy of US-guided pararadicular sacral nerve injections based on CT correlation and anatomic dissection.…”

“…Different approaches have already been described for the cervical [11] and lumbar spine [12], proving the feasibility and effectiveness of US-guided injections in the spine. However, concerning the sacral spine, only a few reports can be found in the literature [13][14][15][16].…”

Pediatric Anesthesia Concerns and Management for Orthopedic Procedures

“…Bordering the sacral hiatus laterally are the sacral cornu, which are bony prominences representing remnants of the inferior articular processes of the fifth sacral vertebra. 24 The sacral cornu are easily palpated in infants and younger children. Once a needle enters the epidural space, local anesthetic can be given as a single injection or a catheter can be threaded up to a desired epidural level to provide continuous analgesia.…”

Kaudal Blok Uygulanan Pediatrik Hastalarda Ultrason İle Konvansiyonel Kör Tekniğin Karşılaştırılması

“…Ultrason rehberliğinde kaudal blok uygulamasında, sakrum, sakral kornular, sakrokoksigeal ligament ve sakral hiatus kolaylıkla ayırt edilebilir. Ayrıca sakral hiatusun ve işlem bölgesinin anatomik varyasyonları da net bir şekilde gözlenebilir [6]. Ultrason rehberliğinde ilerletilen iğnenin istenilen yönde ilerlemesi, lokal anestezik enjeksiyonu ile sakral kanalda genişleme ve renkli Doppler ile sakral kanal içindeki enjeksiyon esnasında türbülans gözlenmesi, enjeksiyonun doğru yapıldığını gösterir.…”