Effused blood under toenail from trauma.
Acute – usually due to knocking toe or dropping object on it
Chronic – foot hitting end of shoe – usually shoe too short; shoe not deep enough; foot sliding in shoe (eg tennis; running downhill)
Usually very painful due to sensitivity of nail bed and pressure between nail bed and nail from effused blood will be very painful to compression
Acute needs decompression – (1) use paper clip in forceps that has been heated in flame burn hole in nail or (2) use a fine burr with nail drill to debride hole in nail
Chronic – debride as much of nail as possible; tubular foam padding around base of hallux (to keep shoe from pushing on nail)
Prevent by use of appropriate footwear – deep, width and lacing system to prevent shoe sliding forward in shoe. Felt padding under tongue of shoe may further help to keep foot from sliding foot.
Dystrophic nail is a common long term consequence will need constant palliative care or permanent surgical removal.