Brief Answer: Most likely trigger finger and requires steroid shot in affected finger. Detailed Answer: Warm Welcome. I appreciate your trust in HCM and assure you are on best portal on the globe for expert online medical services. I have thoroughly reviewed health query you raised, and well realize all of those concerns. Being your physician, I will take care all of them today and will extend my expertise to solve the problems. Based on what you said, your brother is most likely have condition called trigger finger. You also need to mention whether your brother feel painful popping when he straighten the finger. He don’t require any tests to confirm it but finger needs to be examined by orthopedician. I routinely treat patients with trigger finger by a steroid shot in the affected finger and I would recommend it for your brother too. If it doesn’t improve, another trial of steroid shot can be given. If the above strategy fails, then a minor surgery will be required to treat it but most of the time steroid treatment works. Hope I addressed all the concerns you have. Let me know if you have further questions. I will be more than happy to clear any doubts. Keep a follow up to see how you doing. Regards! Dr. Ali Raza