Subungual haematoma, i.e. bleeding into the nail bed (as well as bruising under the nail). For example, mechanical pressure due to poorly fitting, too tight or too short shoes is one of the most notable causes, especially while hiking or doing sports. However, involuntary blunt force by bumping the toe against objects or the edge of the bed or door frame, constantly damaging the toenail, bruising or pinching can also trigger a haematoma.

Its striking red to dark red discolouration because of torn subungual vessels (located in the nail bed) makes the haematoma very easy to recognise. Intense, throbbing and pulsating pain often accompany these signs. The tight space under the nail may cause the nail to lift, ultimately leading to total or partial nail detachment (onychomadesis or
onycholysis).

From fractures to melanoma

After taking a detailed medical history (anamnesis), an inspection is done. The discolouration of the damaged toe or fingernail is immediately noticeable. A bruise or impact could also have broken the phalanx of the toe or finger, which can be seen in X-rays. For differential diagnostics, foot care professionals should also consider the possibility of malignant melanoma (malignant black skin cancer) underneath the nail. The ABCDE rule provides clues: A – asymmetry, B – unclear border, C – colour (brown to black colour), D – diameter (very fast growth),E – elevation (mostly bumpy surface). Certainty is provided only by extracting a sample of the tissue (biopsy).

The best therapy is prevention.

The highest priority is to eliminate triggering causes. First of all, wear appropriate footwear and avoid trauma. Minor haematomas will usually grow out with the nail without complications. In case of severe bleeding, the doctor uses local anaesthesia and drills into the nail with a cannula (trepanation) to drain the blood. To prevent microorganisms such
as bacteria, viruses or fungi from entering, this is done under sterile conditions. The nail is then covered with a sterile dressing, which must be changed the next day.

For pain relief, doctors will prescribe painkillers (analgesics), cryotherapy as well as temporary relief by elevating the foot. For example, GEHWOL med Nail and Skin Protection Oil are suitable for nail care. For pressure relief, GEHWOL pressure protection products for sensitive toes or for existing toe deformations are also an option.

Wolansky, R. W. (2021). Under the nail. FUSSPFLEGEAKTUELLThe Magazine for the Practice Issue 2 / 2021, 24–25.