Factors

Decoding

Predisposing factors

“Internal pressure” factors

Onychomycosis, onychogryphosis, mycosis of the feet, psoriatic lesion of the nail plate of first toe

no

yes

Pathological (flattened, hourly, etc.) shape of the nail and first toe

no

yes

Post-traumatic nail deformity

no

yes

“External Pressure” factors

Hyperkeratosis of the periungual ridges of 1 toe

no

yes

Wearing uncomfortable (tight, high-heeled) shoes

no

yes

Deformity of 1 toe a of the foot (hallux valgus, hallux varus, hallux rigidus)

no

yes

Deformity of the foot (flat feet, clubfoot)

no

yes

Adiposis

no

1-2 degrees

3-4 degrees

Contributing factors

Poor feet hygiene

no

yes

Hyperhidrosis of the feet

no

yes

Diabetes mellitus

no

yes

presence with local trophic disorders

The presence of obliterating vascular diseases of the lower extremities

no

yes

presence with local trophic disorders

Producing factors

Injury of the periungual roller of the first toe with the nail plate

no

yes, due to mechanical injury

yes, due to improper nail clipping