Today's technology has brought us new temperature measuring systems. These tools allow scientists to measure and graph temperatures inside the knee joint. This is helpful because keeping a cool joint can help prevent painful swelling after surgery.
A recent study from Spain measured the temperature inside the knee joint. Measurements were taken during and after arthroscopic surgery. A temperature probe in the joint fluid took the joint temperature every 30 seconds during the operation.
They found the temperature inside the joint was lowered by four degrees after using a saline solution to flush the joint out. The saline solution was kept at room temperature. Other studies also show that the normal temperature inside the knee joint is lower than normal body temperature.
Normal core body temperature is between 97 and 99 degrees F for most people. Internal knee temperature is between 90 and 95 degrees. The difference is most likely due to a fact lack of blood supply to the cartilage in the normal knee.