Great images, so it makes my job really easy,
This is a typical volar plate avulsion injury which has taken a small piece of the base of the Px with it.
This is a common injury (netball is the most common).
The RCL is also torn.
The volar plate and the RCL are simply parts of the joint capsule and the vector of force here has damaged these two components.
Time for some buddy strapping to the ring finger.
I love that you call it the “pinky”
but now we are supposed to call them : Thumb, Index, Middle, Ring and Little. This removes all confusion.
Not 1, 2 , 3 , 4, and 5
and NOT : Hitch-hiker, pointer, rude finger, useless finger and Pinky !!!
Great case Diane, beautiful images.
Steve