If you're scratching your head as to why these two are being compared, keep reading! It'll be very clear in a few short paragraphs. And just to make sure you are on the right page; Yes, these 2 problems both apply to the average golfer. I'm pretty sure if you're experiencing elbow pain you're nodding your head in agreement. So let's get to it, shall we!
I'll first explain the difference between the two problems. Tennis Elbow, or lateral epicondylitis, is inflammation of the extensor muscles of the forearm. There can be a number of explanations but when treating a golfer or tennis player its usually due to excessive forces created when the wrist is held in extension too often under load. Over time these excessive forces irritate the bone on the lateral side, outside, of the elbow. What does this mean? It means your extending the wrist during your swing when you shouldn't be. Most times its occurring in the lead hand, it can happen on the trail hand as well but is much more frequent in the lead hand.
Golfer's elbow is caused the exact same way but with excessive flexion of the wrist during load. Meaning, for a golfer, during the swing your wrist is cocked far too much, resulting in excessive load into the medial epicondylitis or inside of the elbow.
Both of these scenarios can be very painful, even debilitating, if not given the proper medical attention and rest. If by chance you find yourself struggling with this frequently, you may need to seek out professional swing help. The most common symptom for Tennis elbow in golfer's is "chicken winging". If not familiar with this term you DEFINITELY need to seek help with your swing. The reason being is that in the scenario in which you are suffering from Tennis elbow, seek proper medical treatment and don't identify the faulty swing mechanics causing the problem you will be back to the medical physician regularly for the same thing over and over again!
So now the good stuff! So how do I keep this from happening? Easy...... Kinda!! It's easy if you go to the right folks but it's gonna be hard work fixing it once you have a proper diagnosis. With a proper diagnosis of physical limitations, both painful and nonpainful, the medical physician can identify areas for improvement in the physical screen as well as areas that may be constants (things like anatomical anomalies that can't be changed no matter the amount of treatment, scoliosis is a good example) that have to be worked around. Once these variables and constants have been identified communication occurs with the fellow golf pro that now takes this information and uses it to find the most efficient swing for you, as a golfer. This is important because it's important you understand its not about turning you into Tiger Woods or Dustin Johnson but rather finding the swing that is most efficient for your body and body movement.