17 WWW.SPINELINE-DIGITAL.ORG NOVEMBER · DECEMBER 2017 | SPINELINE
Dustin Anderson, MD
Department of Physical Medicine
& Rehabilitation, University of
Aurora, CO, USA
Elizabeth Knight, MD
Alan Best, MD
VA Eastern Colorado Health Care
Denver, CO, USA
A Case Study of Lumbosacral Transitional
Anatomy: Implications of Pain Patterns and
Current Concepts | Case Study & Review
A 42-year-old male with chronic low back pain was referred for an interventional spine
procedure and found to have lumbosacral transitional anatomy. This article reviews the
demographics of lumbosacral transitional vertebrae in the general population based on
radiographic and clinical evidence, the relationship to various etiologies of low back pain,
preprocedure planning and implications in general practice.
Our patient with probable discogenic pain related to a posterior annular tear was scheduled for a left transforaminal epidural steroid injection at the L4-5 interspace. On imaging
review, he was noted to have unilateral “sacralization” with possible pseudoarticulation of
the left L5 transverse process (Figure 1). We took special care to identify the appropriate
level in preprocedure planning and obtained intraoperative fluoroscopic images while
the patient was prone (Figure 2). The procedure was performed without complication
and resulted in resolution of his typical pain.
Fig 1. PA radiograph of lumbar spine showing bilateral hypoplastic ribs at T- 12, five lumbar vertebrae,
and transitional lumbosacral vertebra with pseudoarticulation on the patient’s left (image right).
Fig 2. Intraoperative AP fluoroscopic image shows transforaminal steroid injection at the left L4-5
interspace, with radiopaque contrast dye (second image). Note that left and right are reversed
relative to the prior PA radiograph.