Thoracolumbar fascia in the lumbar region: anatomical description and topographical relationships to the cutaneous nerves: a preliminary study

Background: The study aims to determine principal topographical relations between thoracolumbar fascia (TLF) and lateral branches derived from the dorsal (posterior) rami of lumbar spinal nerves and elucidate their potential link to lumbar region pain. The research protocol involves basic TLF morphological description, evaluating its relation to the nerves, and examining general histology. Materials and methods: The research was conducted on four male cadavers fixed in 10% neutral buffered formalin. Results: The dorsal rami of the spinal nerves branched into medial and lateral divisions. The lateral divisions were about 1 mm thick and mainly visible in the subcutaneous tissue during stratigraphic dissection. They pierced the TLF superficial layer. They descended sidewards and downwards within the superficial fascia (laterally to the erector spinae muscle) to provide sensory innervation to the skin. Conclusions: Anatomical relationships between TLF, deep (intrinsic or true) back muscles, and dorsal rami of the spinal nerves are complex and may be clinically involved in low back pain etiopathogenesis. (Folia Morphol 2024; 83, 2: 417-425)