Umbilical Dermatome Location
Yes, the belly button (umbilicus) is typically located at the T10 dermatome level. This is a well-established anatomical landmark used clinically for sensory assessment and regional anesthesia planning.
Clinical Evidence for T10 Dermatome
- The umbilicus consistently corresponds to the T10 dermatome, serving as a reliable anatomical landmark for sensory nerve distribution assessment 1
- Research confirms that dermatomes T10-T12 are reliably blocked after subcostal transversus abdominis plane (TAP) block procedures, with T10 representing the umbilical level 1
Anatomical Basis
- The umbilicus develops from the primitive umbilical ring during the fourth week of fetal life and becomes a fixed anatomical structure on the ventral abdominal wall 2
- In young adults of normal body habitus, the umbilicus is positioned at approximately 0.7 cm above the iliac crest level, with consistent positioning across different populations 3
- The umbilical region receives abundant sensory innervation including genital end-bulb-like structures, Merkel cells, Meissner and Ruffini corpuscles, and multiple free nerve endings 4
Clinical Applications
- Regional anesthesia planning: The T10 landmark guides subcostal TAP blocks, which reliably anesthetize dermatomes T10-T12 bilaterally 1
- Sensory examination: Testing sensation at the umbilicus assesses T10 nerve root function, distinct from other levels (T4 at nipple line, L1 at inguinal ligament) 1
- Surgical planning: Understanding the T10 dermatome location is essential for abdominal procedures including abdominoplasty and umbilical hernia repairs 4, 3
Common Clinical Pitfall
- Do not confuse the umbilicus location with adjacent dermatomes: T9 lies above the umbilicus at the epigastric region, while T11 extends below toward the suprapubic area 1