Aplasia of the lumbar pedicle is a rare condition, frequently associated with low back pain. Its recognition is fundamental in the definition of the correct treatment. We performed a literature review in order to clarify how to best diagnose and treat this rare anatomical condition. A comprehensive literature search for studies published through October 2020 was performed, using the following algorithm: "aplasia" OR "aplastic" OR "hypoplasia" OR "hypoplastic" OR "absent" OR absence" AND "pedicle" AND "lumbar" OR "sacral" OR "lumbosacral". References from reviewed papers were further evaluated for the inclusion of other relevant studies. Eighteen studies were included in the systematic review for a total of 24 adult patients. Another case of left L5 pedicle aplasia treated at our hospital has been described and included in the present review. This anatomical condition may be suspected in plain x-Ray, but CT scan 3D reconstructions may help to confirm the diagnosis in equivocal cases. Low-back pain and radiculopathy are the main signs and symptoms. The treatment was described in 14 cases. Eight patients underwent surgical intervention. In cases with spondylolisthesis, fusion surgery was performed with different techniques, obtaining an excellent clinical outcome. Pedicular aplasia is a rare condition that must be recognized in patients with a low back. When it is associated with spondylolisthesis, fusion surgery should be the preferred option.
Keywords: Pedicular agenesis; low back pain; lumbar interbody fusion; spondylolisthesis.