Introduction. Intrathecal morphine (ITM) is routinely used in many surgical specialties as an adjunct to postoperative analgesia. There have been multiple reports of the benefits of ITM in lumbar spine surgery where it has been shown to significantly reduce the need for intravenous opioid analgesia, improve time to mobilization, and shorten length of hospital stay.
Anterior lumbar spine surgery (ALSS) includes anterior lumbar interbody fusion (ALIF) and lumbar total disc replacement (TDR). Lateral lumbar spine surgery (LLSS) includes transpsoas lateral lumbar interbody fusion (LLIF), anteromedial to psoas (AMP), or anterior to the psoas oblique lumbar interbody fusion (OLIF). ALSS and LLSS have become mainstay surgical techniques, broadly indicated for the restoration of structural and biomechanical integrity in a variety of degenerative lumbar pathologies. In recent times ALSS and LLSS have increased in popularity with potential benefits of efficient access and direct visualization of the anterior column and disc space, shorter operative times and reduced iatrogenic trauma to paraspinal neurovasculature and musculature.
The widely known method of administering ITM intraoperatively during Lumbar Spine Surgery is via a posterior approach. Although Posterior lumbar spine surgery provides an opportunity for intrathecal injection, a theoretical concern of this is the risk of an iatrogenic cerebrospinal fluid (CSF) leak with dural puncture.
Large numbers of standalone anterior spinal surgeries are performed in our institution. The patient is positioned supine with no access during surgery to the posterior spine and therefore we developed a method of administering ITM through the anterior or lateral approach.
Herein we describe a technique for injection into the dural sac via the Anterior and Lateral approaches to the Lumbar Spine. This technique can be performed easily and quickly with standard surgical equipment. Through use of this technique, patients undergoing spine surgery may benefit from ITM with no risk of iatrogenic CSF leak.