What is the difference between broken skin and a wound?

The same: Anytime the skin is penetrated or opened a wound is created. This can vary from a puncture wound to a large deep opening. "broken skin" can occur from dry skin that cracks open from minor repeated trauma. Your physician can advise you how to care for your wound.

Nothing: When there is a break in the skin then by definition you have a wound.

Definitions: A wound is when there is a break int he skin from an external cause such as a stab wound, a shotgun wound, a traumatic wound. An ulcer is when there is a break in the skin (or lining of an organ) from an internal cause such as a venous insufficiency ulcer, a decubitus ulcer, diabetic neuropathic ulcer or stomach ulcer.

A break in: The integrity of any 'organ', skin included is the definition of a wound no matter what the degree.

Semantics: "broken skin"is a much more generic term. The term "wound" usually but not always has other terms along with it to give a more specific diagnosis. If given either diagnosis you need to ask more questions to find out exactly what's going on.