Multilevel congenital lumbar facet joint aplasia presenting with L5–S1 spondylolisthesis in a patient with connective tissue disease

Background: Congenital facet joint agenesis or hypoplasia is rare, with most reported cases limited to unilateral L5–S1 defects. Case Description: A 40-year-old male with features suggestive of skeletal dysplasia (i.e., short stature, congenital coxa vara, and multiple cardiac and orthopedic anomalies) presented with worsening low back pain and right L5 radiculopathy. The magnetic resonance imaging demonstrated L5–S1 spondylolisthesis with right foraminal stenosis. The 3D computed tomography confirmed multiple absent or hypoplastic facet joints from T12 to S1. He underwent a L5–S1 laminectomy, discectomy, with a transforaminal lumbar interbody fusion (TLIF). Postoperatively, back and leg pain symptoms resolved, and there were no instrument-related complications. Conclusion: This case highlights the congenital absence/hypoplasia of multiple T12-S1 lumbar facet joints, including at the L5S1 level in a patient with likely undiagnosed skeletal dysplasia, successfully managed with a TLIF.