When a peripheral nerve is bruised, stretched, or cut, the area it serves quickly lets you know.

The first hint is often a lightning pain that shoots along the arm or leg at the moment of injury. Later, a deep burn or constant ache may replace it.

Numbness or tingling sets in next. It can feel like the limb “fell asleep,” except the pins-and-needles stay. Hot pans or sharp objects might go unnoticed, leading to accidental burns or cuts.

Muscle weakness shows up fast. You may drop coffee cups, struggle to lift the foot while walking, or find buttons impossible to pinch. Over weeks, the muscle can shrink, leaving a hollow look.

Sweat and skin change. One hand may stay dry while the other drips, or the skin turns shiny and tight. Hair in the area may grow slower.

Temperature control slips. The injured hand or foot can feel ice-cold in warm weather or flush hot at night.

If the nerve is only bruised, symptoms can fade over weeks. If it is fully severed, the muscles may stay weak and the numb patch permanent.