Nail Anatomy

Description

Anatomy of the nail apparatus

Illustration of the nail

Nail bed anatomy

Name

• Fingernail Anatomy
• Nailbed Anatomy
• Nail Apparatus

Function

• Specialized structure of the epidermis that is found at the tips of our fingers and toes
• Protects the tips of our fingers and toes as they are the farthest extremities
• Forms a back-support for picking up small objects with the fingers

Gross Anatomy

• Nail body is composed of densely packed dead keratinocytes
• Nail body forms at the nail root, which has a matrix of proliferating cells from the stratum basale that enables the nail to grow continuously
• Lateral nail fold overlaps the nail on the sides, helping to anchor the nail body
• Eponychium: nail fold that meets the proximal end of the nail body forms the nail cuticle
• Nailbed has a rich vascular matrix
  • Germinal matrix: proximal, gives rise to the new nail
  • Sterile matrix: distal, adds volume and strength
• Lanula: thick layer of epithelium over the nail matrix
• Hyponychium: area beneath the free edge of the nail, furthest from the cuticle
• Paronychium: soft tissue lateral to the nail bed
• Perionychium: paronychium plus the nail bed
• Proximal nail fold (PNF): anatomic transition between the nail bed and the paronychium
• Nail vest: thin veil of tissue forms at the junction of PNF and eponychium

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Clinical Significance

• Nail Bed Lacerations
• Nail Bed Avulsions
• Subungual Hematoma
• Paronychia
• Felon

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See Also

• Hand and Wrist Anatomy (Main)
• Finger Pain (Main)
• Physical Examination Hand

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