Quite a few golfers develop a painful condition, the golfer’s elbow, caused by overuse of two muscles called pronator teres and pronator quadratus in the elbow.
This root cause of this is a common poor golf swing technique of rotating the arm before the hip, which increases the chance of an open club face on impact, hitting the ball at the side rather than the back and causing a slice.
If you have a recurrent pain in the part of the elbow during your golf swing, there is a good chance you may have injured one of these muscles. The pain is usually described as a dull ache during the downswing and upswing. The pronator teres and pronator quadratus are important muscles, they help to stabilize the arm in position during the golf swing. However, they are not to be used excessively to align the club head, the alignment of the club head should come from the hip turning to the left. Then after the hips are properly turned to the left, the muscles are then engaged to finish up the alignment and produce a closed club face
If the hips are not adequately rotated to the left, the club face is open at impact leading to a slice.
The golfer then tries to prevent the slice by over pronating the forearm, excessively stressing both muscles, leading to possible injury
You can prevent this by ensuring the hips are moved first, before the arms and ensure your starting grip is strong to avoid over pronating. You will have a better chance to hit the ball at the back, have a straight shot down the fairway
This injury typically lasts a few months, I recommend visiting a family medicine physician, getting evaluated and fitted with an appropriate durable medical equipment and then you may need to start physical therapy for some weeks