Ballottement is a medical sign that indicates the presence of increased fluid or a solid mass within a body cavity. It is commonly used to diagnose pregnancy, ascites, or joint effusion. Ballottement involves applying a sudden upward or downward pressure on the cavity wall and feeling the return impact of the displaced fluid or mass.

Ballottement can be used to detect pregnancy by feeling the movement of the fetus in the uterus. To perform ballottement in pregnancy, the examiner inserts a finger into the vagina and pushes upward against the uterine wall. If the fetus is present, it will move away from the pressure and then bounce back, hitting the finger. This sign can be detected as early as the fourth or fifth month of pregnancy.

Ascites is a condition where fluid accumulates in the abdominal cavity, often due to liver disease, heart failure, or cancer. Ballottement can be used to identify an organ or a mass in an ascitic abdomen. To perform ballottement in ascites, the examiner places one hand on the abdominal surface and makes a brief jabbing movement directly toward the suspected structure. This quick movement displaces the fluid so that the fingertips can briefly touch the surface of the structure through the abdominal wall.

Joint effusion is a condition where excess fluid accumulates in a joint space, often due to inflammation, infection, or injury. Ballottement can be used to assess the amount of fluid in a joint, especially the knee joint. To perform ballottement in joint effusion, the examiner applies downward pressure towards the foot with one hand, while pushing the patella (kneecap) backwards against the femur (thigh bone) with one finger of the opposite hand. A “milking” motion is used with the downward pressure. If there is fluid in the joint, the patella will move freely and bounce back when released.

1. Bickley, Lynn S. (2003). Bates’ Guide to Physical Examination and History Taking. Philadelphia: Lippincott. p. 347.
2. “Ballottement.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/ballottement.
3. “Ballottement.” Wikipedia, https://en.wikipedia.org/wiki/Ballottement.

Ballottement is a simple and inexpensive technique that can provide useful information about the presence and location of fluid or masses in body cavities. It can help diagnose conditions such as pregnancy, ascites, and joint effusion without the need for invasive procedures or expensive equipment. However, ballottement also has some limitations and drawbacks. For example:

• Ballottement may not be reliable or accurate in some cases, such as when the fluid or mass is too small, too large, too deep, or too adherent to the cavity wall.
• Ballottement may not be feasible or comfortable for some patients, such as those who are obese, have abdominal pain, have vaginal bleeding, or have a history of pelvic inflammatory disease.
• Ballottement may not be specific or conclusive for some conditions, such as when the fluid or mass is due to multiple causes, has an uncertain origin, or requires further confirmation by other tests.

Ballottement is a physical sign that involves applying pressure on a body cavity wall and feeling the return impact of the displaced fluid or mass. It can be used to detect pregnancy, ascites, or joint effusion in various body cavities. Ballottement is a simple and inexpensive technique that can provide useful information without the need for invasive procedures or expensive equipment. However, ballottement also has some limitations and drawbacks that may affect its reliability, accuracy, feasibility, comfort, specificity, and conclusiveness. Therefore, ballottement should be used with caution and in conjunction with other clinical findings and tests.