Related Experiment Video
Updated: Aug 12, 2026

13:58
Flat Mount Imaging of Mouse Skin and Its Application to the Analysis of Hair Follicle Patterning and Sensory Axon Morphology
Published on: June 25, 2014
[Structural abnormalities of the hair shaft]
1Hudavdelingen, Ullevål sykehus, Oslo.
Summary
Diagnosing hair shaft abnormalities is clinically important as they can signal metabolic disorders or other diseases. These conditions often cause alopecia due to increased hair fragility.
Area of Science:
- Dermatology
- Genetics
- Biochemistry
Background:
- Structural hair shaft abnormalities are clinically significant.
- These conditions can be indicators of underlying metabolic disorders or associated diseases.
- Many hair shaft abnormalities manifest as alopecia due to increased hair fragility.
Observation:
- Common hair shaft abnormalities include trichorrhexis nodosa, pili torti, and "uncombable hair" syndrome.
- These conditions are observed in patients presenting with hair fragility and hair loss.
- Specific examples like pili torti et canaliculi are also noted.
Findings:
- Identification of specific structural defects in the hair shaft.
- Correlation between hair shaft abnormalities and underlying systemic conditions.
- Understanding the pathomechanisms leading to increased hair fragility and alopecia.
Implications:
- Improved diagnostic approaches for alopecia and related conditions.
- Potential for early detection of metabolic disorders through hair examination.
- Enhanced understanding of hair biology and its clinical manifestations.
Related Concept Videos
Multipotency and Niche of Bulge Stem Cell
A hair follicle or HF is a small part of the skin that produces the hair shaft. Paul Gerson Unna was the first to observe a bulge in the human hair follicle's outer root sheath (ORS). The bulge is present between the sebaceous gland and the arrector pili muscle and is the niche for hair follicle stem cells (HFSCs). The bulge is also a niche for melanocyte stem cells, and their loss results in graying of hair. The HFSCs express Sox9 and Lhx2, which help them maintain stemness and prevent...
Accessory Structures of the Skin: Hair and Hair Follicles
Hair and hair follicles are integral components of the integumentary system. Hair is a filamentous structure composed mainly of a protein called keratin. It is found on the surface of the skin throughout the body, except for areas such as the palms of the hands and soles of the feet.
Hair is a keratinous filament growing out of the epidermis. It is primarily made of dead, keratinized cells. Hair strands originate at the epidermal penetration called the hair follicle. The hair shaft is the part...
Hair is a keratinous filament growing out of the epidermis. It is primarily made of dead, keratinized cells. Hair strands originate at the epidermal penetration called the hair follicle. The hair shaft is the part...
Accessory Structures of the Skin: Hair Growth and Types
Hair growth begins with the production of keratinocytes by the basal cells of the hair bulb. As new cells are deposited at the hair bulb, the hair shaft is pushed through the follicle toward the surface. Keratinization is completed as the cells are pushed to the skin surface to form the shaft of hair that is externally visible. The external hair is completely dead and composed entirely of keratin. Hair can be cut or shaven without damaging the hair structure because the cut is superficial. Most...
Accessory Structures of the Skin: Nails
Nails are one of the important accessory structures of the skin. They are hard, protective structures that cover the dorsal surface of the distal phalanges of fingers and toes. Nails are composed of specialized keratinized cells and serve various functions, including protection, sensation, and manual dexterity.
The main components of a nail include the following.
Nail Plate: The nail plate is the visible portion of the nail that extends beyond the fingertips or toes. It is a hard, translucent...
The main components of a nail include the following.
Nail Plate: The nail plate is the visible portion of the nail that extends beyond the fingertips or toes. It is a hard, translucent...
Classification of Bones
The bones of the human skeletal system are of varied shapes, sizes, and functions. They can be classified based on their shape and function into four major classes: long bones, short bones, flat bones, and irregular bones. Some classifications include a fifth type, the sesamoid bones, as a separate class, whereas others categorize them under short bones.
Long and Short Bones
The appendicular skeleton, particularly the upper and lower limbs, is primarily made of long and short bones. The long...
Long and Short Bones
The appendicular skeleton, particularly the upper and lower limbs, is primarily made of long and short bones. The long...
Gross Anatomy of Bone
The two main features of a long bone are the diaphysis and the epiphysis.
The diaphysis is the tubular shaft that runs between the proximal and distal ends of the bone. The walls of the diaphysis are composed of dense and hard compact bone made of numerous osteons — the functional unit of the compact bone. The hollow region in the diaphysis is called the medullary cavity, which harbors the bone marrow. In infants and children, this marrow cavity is filled with red marrow, whereas in adults, it...
The diaphysis is the tubular shaft that runs between the proximal and distal ends of the bone. The walls of the diaphysis are composed of dense and hard compact bone made of numerous osteons — the functional unit of the compact bone. The hollow region in the diaphysis is called the medullary cavity, which harbors the bone marrow. In infants and children, this marrow cavity is filled with red marrow, whereas in adults, it...

