“My son was pitching and elbow became sore.”
Where on the Elbow? By the sounds of it the pain should emanate at the back of the Elbow where the triceps anchors to the Elbow?
He now has pain near the elbow and pinkie and index finger are numb.
The Ulnar nerve controls one half of the middle finger towards the ring finger, ring finger and little finger
The radial nerve controls the half the middle finger towards the index finger, index finger and thumb.
Normally the Ulnar nerve is involved at the back of the elbow from throwing, it gets irritated from ballistic Hyper extension form forearm supinated pitch types.
Fortunately this is easily fixed with outpatient surgery to trans locate the nerve out of it’s groove and to the side of the Elbow with a very short recovery.
“We tried the chiropractor with no success. Pain is 8/9 with no relief.”
You need a sport specialist Orthopedic Dr. Go to ASMI and ask for a recommendation for your area, this is what they do best.
“MRI on Tuesday. Does the numb feeling occur with a tear or only nervevisdues”
A tear in the MCL (UCL) will have no signal accept laxity in the Elbow. Ligaments do not have pain receptors and micro tear daily with poor force application. Forearm flexor Tendons are what barks at that location.
When he gets his Dr’s release to go again, you might want him to change his arm arrival timing to mitigate this problem and most importantly he needs to learn how to forearm pronate his ball drives to eliminate the ballistic bone crunch he produces.