What do different nail shapes indicate about my health?

Nail Shapes and Their Health Implications

Different nail shapes can indicate various health conditions, with vertical ridges often being a normal part of aging, while other changes may signal underlying diseases requiring medical attention. 1

Common Nail Shapes and Their Meanings

Vertical Ridges

• Vertical ridges running from cuticle to nail tip are often a normal sign of aging as the nail matrix's ability to produce smooth nails diminishes 1
• Can also be associated with inflammatory conditions like lichen planus or psoriasis, causing nail thinning and longitudinal ridging 1
• May indicate Darier disease (a rare genetic disorder) that causes nail dystrophy including ridging 1
• Can result from repetitive trauma or excessive moisture exposure, particularly in occupations requiring frequent hand washing 1, 2

Brittle Nails (Onychorrhexis)

• Characterized by longitudinal ridging with splitting or brittleness of the nail plate 2
• May indicate systemic conditions, medication side effects, or nail matrix damage 2
• Often accompanied by thinning of the nail plate and increased fragility 2
• Can be prevented with daily use of topical emollients on periungual folds and protective nail lacquers 2

Clubbing

• Characterized by enlarged fingertips and curved nails that wrap around fingertips 3
• Often suggests underlying pulmonary disease or inflammatory bowel disease 3
• Represents a critical finding during physical examination, especially in smokers 4

Spoon-Shaped Nails (Koilonychia)

• Nails with a concave shape that may hold a drop of water 3
• Should prompt investigation for hemochromatosis or anemia 3
• May also be associated with connective tissue disorders 3

Onycholysis (Nail Separation)

• Separation of nail from nail bed, often starting at the tip 5, 3
• In the absence of trauma or psoriasis, should prompt evaluation for hyperthyroidism 3
• Can also be seen in fungal infections (onychomycosis) 5

Beau's Lines

• Horizontal depressions across the nails 3
• May indicate previous severe illness, trauma, or exposure to cold temperatures in patients with Raynaud's disease 3
• Represent temporary disruption of nail growth during illness 6

Nail Discoloration Patterns

Green Nail Syndrome

• Characterized by green discoloration, typically due to Pseudomonas infection 7
• Treatment includes keeping the affected area dry and applying topical povidone iodine 2% twice daily 7
• Prevention involves proper nail care, avoiding cutting nails too short, and wearing gloves during wet work 7

Half and Half Nails (Lindsay's Nails)

• White coloration of proximal half with red-brown distal half 8
• Commonly associated with chronic kidney disease (seen in 20-50% of patients) 8
• Can also occur in Crohn's disease, Behçet's disease, cirrhosis, and even healthy individuals 8

Fungal Nail Infections (Onychomycosis)

• Presents with thickening, discoloration, and friable texture of nails 5, 1
• More commonly affects toenails than fingernails 1
• Different patterns include distal lateral subungual onychomycosis, superficial white onychomycosis, and proximal subungual onychomycosis 5

When to Seek Medical Attention

• Medical evaluation is recommended if nail changes appear suddenly, change rapidly, or are associated with pain, inflammation, or nail separation 1
• Longitudinal melanonychia (dark streaks in the nail) warrants investigation to rule out subungual melanoma 6
• Splinter hemorrhages in patients with heart murmur and unexplained fever may indicate endocarditis 3
• Nail changes that interfere with daily activities require prompt evaluation 6

Preventive Nail Care

• Apply daily topical emollients to cuticles and periungual tissues 2, 7
• Avoid excessive moisture exposure and wear gloves while cleaning or working with chemicals 1, 7
• Prevent trauma to nails and avoid cutting nails too short 7
• Maintain proper nail hygiene to prevent infections 7