Elbow problems are common among amateur and professional golfers. And there's a wide range of causes for the same symptoms. An orthopedic surgeon will have to sort out your symptoms before a diagnosis can be made.
Examination of your pain, motion, and strength is important. Special movement tests will help point to nerve, tendon, ligament, or joint problems. Many times golfers are told the problem is lateral epicondylitis also known as "tennis elbow."
According to a recent study half of the patients with lateral elbow pain were given this diagnosis when it wasn't the problem at all. Further testing with MRI and arthroscopy showed an extra piece of synovium called plica was the real cause of the symptoms.
Plica forms in the knee or elbow at the point where several pieces of synovium come together. The synovium is the thin layer of tissue that lines the joints and keeps the lubricating (synovial) fluid inside the joint.
The plica is an extra fold of synovium that gets caught in or pinched by the joint during motion. This may be what's keeping your elbow from extending all the way. Seek professional help if the problem doesn't go away. You may be able to get control of your symptoms with medications and exercise.