What Causes Shoulder Pain After The Car Accident?

i wa in a car accident nearly 3 years ago i hve beensuffering with pain and lack of movement in the right shoulder arm i have had 5 lots of osio with different physios seen a orthopidic surgeon saw a shoulder specialist had a operation this year for impingement of the shoulder which i got 85-90% movement back in the arm but the pain has not gone away i an now waiting an appointment to see another ortopedic surgeon but nobody nows why i am still in pain any help