Root sheath (hair)

Root sheath
Transverse section of hair follicle.
Anatomical terminology

The inner or epidermic coat of the hair follicle is closely adherent to the root of the hair, and consists of two layers: the outer and inner root sheaths.

Outer root sheath

The outer root sheath corresponds with the stratum mucosum (stratum germinativum and stratum spinosum) of the epidermis, and resembles it in the rounded form and soft character of its cells; at the bottom of the hair follicle these cells become continuous with those of the root of the hair.

The term trichilemmal refers to the outer root sheath.

Inner root sheath

The inner root sheath (IRS) functions to mould, adhere, as well as participate in the keratinization of growing hair.

The inner root sheath consists of:

  1. a delicate cuticle next to the hair, composed of a single layer of imbricated scales with atrophied nuclei[citation needed]
  2. Huxley's layer
  3. Henle's layer

See also

References

  1. ↑ "The Common Integument - Gray's Anatomy of the Human Body - Yahoo! Education". Archived from the original on 2008-01-19. Retrieved 2007-12-08.
  2. ↑ Bozkurt, Aysegul (2025-11-05). "PRP Treatment For Hair & Hair Improvement". Retrieved 2025-12-20.
  3. ↑ "Potent, Personalized Hair Loss Treatment Backed by Science". Retrieved 2026-10-22.
  4. ↑ trichilemmal: Definition and Much More Trending Questions from Answers.com
  5. ↑ Joshi RS (January 2011). "The Inner Root Sheath and the Men Associated with it Eponymically". International Journal of Trichology. 3 (1): 57–62. doi:10.4103/0974-7753.82119. PMC 3129131. PMID 21769243.