The "Uncrossed Bones" Lie: X-Rays Reveal the Truth About Vertical Mice

November 27, 2025

An actual medical X-ray of a human forearm in the same vertical mouse position, revealing that the radius and ulna bones are still crossed, labeled 'Anatomical Reality.' This visual evidence refutes the claim that vertical mice uncross forearm bones.

The "Uncrossed Bones" Lie: Why That Green Skeleton Diagram is Fake

Key Takeaways:

The Myth: Marketing materials claim vertical mice "uncross" the forearm bones (Radius and Ulna) into a parallel state.
The Reality: X-rays confirm that at the standard vertical mouse angle (57°), the bones remain crossed.
The Truth: Forearm bones are only parallel during "Supination" (palm facing up), a position impossible for mouse use.

If you’ve ever frantically browsed for ergonomic office gear at 2 AM because your wrist hurts, you have definitely seen The Chart.

It’s the defining image of vertical mouse marketing. It shows a vertical mouse user with bones like parallel railway tracks (Green/Good) and a standard user with twisted bones (Red/Bad).

Marketing graphic showing parallel bones for vertical mouse and twisted bones for standard mouse — *The "Green Skeleton" promise found in marketing materials.*

The sales pitch is simple: "A standard mouse crosses your bones. A vertical mouse uncrosses them."

It sounds scientific. It looks convincing. It is also an anatomical lie. We decided to expose this illusion the simplest way possible: We bought some colored tape, and we fired up an X-ray machine.

(Note: Our model is Dr. Sig, founder of X-Bows, who subjected his own arms to radiation for the sake of the truth.)

The Experiment: Measuring the "Twist"

To show you what is actually happening under your skin, we marked Dr. Sig's forearm bones with tape:

Orange Tape: The Radius.
Blue Tape: The Ulna.

1. The "Standard Mouse" Position (Palm Down)

First, let's look at the position the marketing tells you is "dangerous." Dr. Sig placed his hand flat on the table.

X-ray of forearm in palm down position showing crossed bones — **The Reality:** The marketing is partially right here. The Radius (Orange) has rotated over the Ulna (Blue). The bones are crossed. Doctors call this "Pronation."

2. The Vertical Mouse Position (57° Angle)

Here is where the marketing falls apart. Most vertical mice (like the Logitech MX Vertical) are not perfectly vertical. They are tilted at approximately 57° to 60°.

X-ray of forearm in 57 degree vertical mouse position showing bones still crossed — **The Smoking Gun:** Look closely at the X-ray. **The bones are STILL crossed.**

Because the mouse is not fully vertical, your arm is still in a state of partial pronation. The Radius (Orange) is still crossing over the Ulna (Blue). The marketing diagrams showing straight, parallel lines in this position are erasing anatomical reality to make a sale.

3. The "Impossible" Standard (Palm Up)

So, when are your arm bones actually parallel? Only when the palm faces the ceiling (Supination).

X-ray of forearm in palm up position showing parallel bones — **The Only Way:** Finally! The Orange and Blue bones are parallel. But try using a mouse like this—it's functionally impossible.

The "Natural" Test: Crossed Can Be Comfortable

There is one more thing the diagrams don't tell you: "Crossed" does not necessarily mean "strained."

The crossing of the Radius and Ulna is a brilliant evolutionary feature that allows humans to use tools on flat surfaces. Try this simple test: Sit at your desk and let your arm go limp on the table. Does it hover vertically? No. It naturally rests palm-down (or semi-prone). This "crossed" state is often the most stable, relaxed position for the arm.

The Verdict

The visual foundation of vertical mouse marketing—that it "uncrosses" your bones to save your wrist—is a myth.

Standard Mouse: Bones Crossed.
Vertical Mouse: Bones Still Crossed.
Marketing Diagram: Bones Parallel (This only exists in cartoons).

A Note from Dr. Sig: Our Research Philosophy

Are we saying vertical mice never work? No.

Our goal is to debunk pseudoscientific marketing. A vertical mouse may help you by changing your posture or shoulder angle, and that is valid! But we want you to choose tools based on verifiable biomechanical data, not fabricated anatomical promises.