According to WebMD, water on the elbow, or bursitis, is caused by pressure on the bursa, a blow to the elbow or an infection. Of these causes, pressure is the most prevalent. In fact, it is called student's elbow because students lean on their elbows while studying, which puts pressure on the bursa and causes inflammation, according to John Hopkins Medicine.
WebMD describes water on the elbow as a condition in which the bursa, which are sacs of fluid located on the elbow that lubricate the joint, swell up. Besides swelling, other symptoms include pain, tenderness, redness and fever. Once bursitis sets in, the sac needs to be drained of fluid and anti-inflammatory medicine must be injected into it. John Hopkins Medicine points out that icing and compressing the affected area also help to relieve the swelling. In the cases of infection, antibiotics need to be administered and the condition needs to be evaluated by a doctor immediately. In cases of chronic bursitis, the joint needs to be immobilized to decrease the friction and pressure on the bursa.
There are a few ways to prevent bursitis. WebMD emphasizes the need for elbow protection, such as elbow pads, particularly in sports that potentially cause a hard impact to the elbow that can cause this condition. Another prevention measure is to avoid leaning on the elbows.