Black eye: Why bruising under the eye, where there was no impact?

After I gave myself a small bruise under the right eye by falling on my face yesterday I wonder why the bruise is at a different place from the actual impact.

Photograph, about 28 hours aftewards. My face hit the floor where the minor cut on the cheekbone is, in the lower left quadrant. (The very shallow cut is from the edge of my eyeglasses - unbreakable sports glasses, fortunately.) - but there is no noticeable bruise where the face hit the floor, just under the eye - an area that is noticeable recessed and was wholly covered by my large glasses, so it cannot have been hit). The darker colour overall in the eye socket is due to ordinary lack of sleep. (BTW no neurological or vision symptoms at all - it was a pretty light fall.)

So what caused the bruise under the eye? I seem to recollect that shape of bruise is pretty common with minor cases of black eye I have seen on others.

Bruising is bleeding under the skin, the blood drains down from gravity.

You might find this article of interest:

Also the skin around the eye is very elastic while the skin elsewhere on the face is more tioghtly adherant - blood is squeezed out of the tight spots to where the subQ space can more easily expand.

I had a friend who had to have surgery on her eyelids. During her recovery period, she looked like she’d been in a really nasty bar fight. Yes, her eyelids were puffy, but she had huge black bruises underneath her eyes. All the fluid and blood from the surgery had drained down to the circles under her eyes.

One of her neighbors thought she’d been beaten up.

Subcutaneous blood tracks along fascial planes.
The infraorbital region is a common place for fluid and blood to accumulate, particularly after a period of recumbency such as sleeping.

Another common example is a shin bruise or lower leg. Blood there often drains subcutaneously all the way down to the foot and collects there on each side of the foot below the medial and lateral ankle.

Yep! Speaking from personal experience (several sprained ankles), I’ve had some spectacular bruising (seriously - the colors and range were impressive) on my feet, nowhere near the actual sprain location. The bruise seems to migrate a bit forward over a period of several days.