Nail Anatomy and Pathology Flashcards
What is Onychauxis (Hypertrophied Nail)
Uniform thickening of the nail plate from nail base to free edge
Aetiology - Damage to the nail Matrix with one or more causes
1. Fungal infection of the nail
2. Poor peripheral circulation
3. Single major trauma from a heavy blow
4. repeated minor trauma from ill fitting footwear
Pathology
* Changes in the nail fold main cause of hypertrophy
Onychogryphosis
- Thickened nail with a distortion in the direction of growth
- Longitudinal transverse ridges
- Rams Horn
Aetiology:
* same as Onychauxis
* fungal infection
* Single trauma
* poor peripheral circulation
What is Onycholysis
- Seperation of nail from the nail bed often Distal to Proximal
- white apperance from air getting underneath the nail
Aetiology: - Onychomycosis
- Trauma
- Systemic involvement possible ie poor circulation
Pathology: - increased pressure of the nail bed can cause infection and inflamattion
- Hard keratinogenous material gather underneath the nail
Treatment - Cut nail back in stages
- referal to GP if systemic
- Treat any fungal involvement
Whatv is Onychomadesis
Seperationn of nail form nail bed proximal to distal
What is Onychocryptosis
- Ingrowing toe nail - A spike or splinter edge of the nail penetrates the sulcus entring the dermal tissue
- Bi Lateral or unilateral
Aetiology: - cutting nails too short
- Cutting obliquely
- Hyperdydrosis causes surrounding tissue to become macerated/soaked in mositure making the surrounding tissue less resistant to pressure form the nail
- Pressure form ill fitting footwear
What is Involution
Increased transverse curvature of the nail plate unilateral or bi lateral
Aetiology:
* ill fitting footwear
* Trauma
* poor nail cutting
* systemic diseases
Pathoogy:
* Trauma to the nail plate causes increased transverse curvature
* Sysetmic/malnutriton disease of the extremities leads to alteration of the cell division between layer in the nail plate causing distortion in growth
Treatment:
* Cut the nail accordingly to release pressure in the sulci
* Partial or total nail removal may be long term option
What is a Splinter Heamorage
Longitudinal plum coloured linear haemorage under the nail plate
What is Paronychia
Inflamattion of the tissue surrounding the nail
What is Onychomycosis
Fungal Infection of the nail plate caused by Dermatophytes, non dermatophytes and yeasts
What is Chromonychia
Abnormal colouration of the nail tissue
What is Koilonychia
Transverse and longitudinal concave nail dystrophy
Spoon shaped nail
What are Dermatophytes
Pathogenic Fungus that can invade the nail infecting keratinous tissue
List three types of dermaphytes
Trichophyton
Epidermophyton
Microsporum
What are the most common Dermatophytes associated with Onychomycosis
Trichophyton rubrum and T interdigitale
What are the non dermataphytes that cause Onychomycosis
Moulds - Scorpularis Brevicaulis
Yeasts - Candida Albicans
What are the predisposing factors causing Onychmycosis
Old age
Trauma
Diabetes
Immunosupresed patients
Previous history of nail psoriasis and tinea pedis
Pneumonic for classifications of onychomycosis
Endor
Died Last Sunday
Susan Whepped
Propper Suprised
Totally Distraught
List the 5 types/ classifications of Onychomycosis
Endonyx
Distal & Lateral Subungal Onychomycosis
Superficial white Onychomycosis
Proximal Subungal Onychomycosis
Total Dytrophic Onychomycosis
What are the features of Superficial White Onychomycosis
Mainly affects the toe nails
White patches on the superficial part of the toenail
Doesnt respond well to topical treatment
What are the features of Proximal subungal onychomycosis
More common in toenails than fingernails
Area of infection Proximal nail fold and nail plate
White appearance spreading distally
dermaphytes involved commonly T - Rubrum
No thickening of the nail plate
High prevelance in HIV and Aids patients
What are the features of Endonyx Onychomycosis
Caused by T Soudansense
Area of infection = margian of the nail plate
White in apperance no seperation of the nail from the nail bed (onycholysis) or no chalky substance underneath the nail (subungal Hyperkeratosis)
What are the clinical features of Onychmycosis
Thickened Naill
Crumbly Nial
Rough/Irregular appearance
Varying in colour white, yellow, brown black
Can be painful but usually affects patient confidence due to apperance
Give the name of a topical anti fungal treantment used to treat Onychomycosis
Amoroline - Loycerel, Curanail
Define Pathology
Science of the casuses and effects of disease
What is the Perionychium
The tissue surrounding the nail
What is the nail plate
- The nail plate is a hard protective structure made from transluscent keratin
- Contains a rich vascular network
What is the Eponychium
Also reffered to as the cuticle helps to prevent the entry of bacteria to the Ventral Proximal Nail fold
What is the Hyponichium
- Distal to the nail bed underneath the free edge of the nail plate
- It forms a seal that protects the nail bed
What is the lunula
White half moon apperance due to the reflection of the light between the nail and the nail bed
Nail plate is thinner here
What is the Nail Matrix
The nail matrix produces new cells which become the nail plate
It also determines the width and thickness of the nail
What is the germinal matrix
- The germinal matrix is collective term given to the root and sinus of the nail
- The growth of the nail starts here
What is the Nial Bed
- Also reffered to as the sterile matrix
- lies underneath the nail plate has a rich vascular supply
- Extends from the nail matrix to the Hyponichium
- No subcutaneus tissue beneath the nail bed so it attaches directly to the periosteum of the distal phalanx
What is Total Nail Dystrophic Onychomycosis
- Infection of the whole nail plate
- Yellow irregular appearance causing total destruction of the nail
- Usually a cobination of Candida and dermatophytes
- Seen in immunosupressed patients
What are the conservative management treatments for onychmycosis
Conservattive - Topical treatments include:
* Amorolfine
* Terbinafine
* Triconazole
What are the Systemic oral treatments for Onychomycosis
Systemic - Oral treatments
* Grisofulvin - in children
* Terbinafine and Itraconazole
* Fluconazole - for Candida infection
Describe the pathology of Onychocryptosis
Pathology:
* Normal healing is distrupted by the continued penetration of the spike causing hypergranulation
* This excessive growth of tissue results in the nail fold overlapping the nail plate
* Pus is frequentley presnet and can exude for the sulcus or pool in the pocket lying beneath the sulcus
What are the three stages of Onychocryptosis
Stage 1 - minimal injury to sulcus
symptoms of pain, slight swelling oedema (fluid build up)
Stage 2 - Acute Pain, erythema (redness) hyperhydrolosis, granulation tissue with odour
Stage 3 - Consistent with stage 2 plus epidermal overgrowth, hypergranulation
What is Subungal Extosis
Small outgrowth of bone underneath the nail plate distally near the free edge
Symptoms - Include Pain and nail plate deformation
**Aetiology **- Unknown although it is thought that a history of trauma and microtrauma may play a part
Treatment:
* Protective padding and advice on footwear
* Surgical Excision
