What kind of image is this?
It’s an x-ray.
What is it an image of?
It’s an x-ray of a person’s hand.
What are the brighter white things in the image?
They are bones.
About how old is this person?
The person is very young, under three years old.
Why are there such big spaces between the bones?
The bones do not look like they are touch each other because the ends of the bones have no calcium in them and therefore do not show up on the x-ray. The bones are longer than they appear and they do touch.
What are the names of the bones that show up on the x-ray?
The finger bones are called phalanges. Each finger has a proximal, middle and distal phalanx. The thumb has only a proximal and distal phalanx. The bones in the hand are called metacarpals. The bones in the forearm are the radius and ulna. The radius flairs at its distal end (which is seen in the x-ray). The ulnar is larger at its proximal end (which cannot be seen).
What bones appear to be missing?
The bones of the wrist, called the carpal bones, calcify later in life and therefore do not show up on this x-ray.
Which side is it on?
It’s the left hand, as indicated by the “L” in the lower right-hand corner.
What other clue indicates the side?
The only thing that indicates that this is an x-ray of a left hand taken palm down instead of an x-ray of a right hand taken palm up is that the radius and ulna are crossed. This is the typical way a hand x-ray is taken, with the palm of the hand lying on top of the x-ray detector and the x-rays penetrating from the back of the hand through the palm to the detector.
What is the black rectangle to the left of the L for?
This is likely where the patient’s identifying information, including his or her name, date of birth, medical record number and the date of the exam, were on the original x-ray. These have been blacked out for patient confidentiality. The corner of the black rectangle that cuts into the hand is an indication that this rectangle was not present on the original x-ray.
Bonus: Give two reasons why this x-ray might have been taken?
Obviously, there might have been concern for an injury, however, no injury is found on this x-ray.
It is also customary to take an x-ray of the left hand to determine “bone age” to see if a child’s bones are developing at an appropriate rate compared to the child’s true age. There are several diseases that can cause a child’s bones to mature at a different rate than expected. There are standard references that radiologists use to compare what is considered normal. These references all have pictures of left hands.
What three types of injuries might be seen on an x-ray?
The three major injuries that can be seen on an x-ray are fractures, joint dislocations and embedded metallic objects.
CoMo Science 
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