The description of your index finger matches mine exactly. I have seen three different hand surgeons all with different opinions. What is a person to do???I will say two felt immbolizing  the finger was the wrong thing to do. It will atrophy and be even worse. The Doctor I saw today whom treats proffessional football players said that I cannot tear my ligament more. I play competetive tennis and eventually I will have to have surgery to repair the torn ligament but I have peace of mind that I can play without causing more damage. Hope this helps.