How deep can we insert acupoints in the lower back

An interesting study on the depth from the skin to the transverse processes and facet joints of the lumbar vertebrae, using MRI was recently reported by a research team from Chung-Yeon Central Institute, Korea. The retrospective study screened 158 subjects from 55,129 scanning films. The outcome suggested that the depth from skin to the transverse processes or facet joints be unaffected by age, sex, or side. The mean depths (cm) were as follows: (transverse processes) L1 = 4.5, L2 = 4.9, L3 = 5.3, L4 = 5.7, L5 = 5.9; (facet joints) L12 = 3.8, L23 = 4.0, L34 = 4.4, L45 = 4.6, L5S1 = 4.6. Depth was highly correlated with BMI at each location.

Reference

Yoon SH, Kim SA, Lee GY et al. Using magnetic resonance imaging to measure the depth of acupotomy points in the lumbar spine: a retrospective study. Integrative Medicine Research, 2020. https://doi.org/10.1016/j.imr.2020.100679