Error in describing the location of the space. The space is between the 3rd and 4th *digits*, or the 2nd and 3rd *fingers*. The thumb is not a finger!
I changed the wording to match Amboss’ description which avoids numbers altogether, and is therefore a bit clearer in my opinion.
The text in the Extra image will need to be corrected also.
Skeletal dysplasias > Achondroplasia > Clinical features
“Trident hand: a deformity of the hand that is characterized by short stubby fingers of equal size and increased separation between the middle finger and ring finger, which gives the hand the three-pronged appearance of a trident”
https://next.amboss.com/us/article/wH0hsh?q=trident%20hand#Z51bc7c6fc6aa192b53297a6a2128acf7