HappyHappyJoyJoy,
Usually, the main symptom of a loose body (also called a "joint mouse") within a joint is locking of the joint. Just as if someone had put a chock in there. Most loose bodies are the result of trauma to the joint. Loose bodies can be made of bone, cartilage, or a combination of both.
If the patient tries to move the joint past the stopping point, there will usually be quite a bit of pain, then the joint will pop or snap as it goes over the loose body.
Loose bodies that are free floating within the joint will move around. Thus, making the episodes of when the locking occurs very sporadic. The patient never really knows when it is going to happen. This also makes it hard to find the loose body on x-ray (if it is a bony loose body), because it can be anywhere in the joint, and never in the same place twice. Nowadays, with CT scan and MRI, it is a lot easier to find loose bodies. Sometimes, an MR arthrogram has to be done, so that the loose body can be outlined by the Gadolinium contrast material.
However, there are some loose bodies which are actually attached to the synovium (joint lining). These loose bodies stay in one spot, so their symptoms are more predictable and they are usually easier to find.
There is a condition in which the patient makes many loose bodies within a joint. This is called synovial osteochondromatosis. This is a different condition from that of having just one loose body in a joint.
However, a bipartate patella is not the same as a loose body, nor a contained loose body within the synovium. Usually, a bipartate patella is congenital; the patient is born with the condition. Most of the time, a bipartate patella causes the patient no problems throughout life. If the cartilage bridge between the two pieces is disrupted and does not heal, then the patient may develop some discomfort around the patella.
A bipartate patella is not the same as a patellar fracture. Patients with a patellar fracture have a break through bone, and this injury usually heals bone to bone. Though, some patellar fractures can go on to a nonunion, where the two fragments are connected with fibrous tissue. These nonunions are sometimes mistaken for bipartate patellae.
Treatment of a bipartate patella depends upon the symptoms the patient is having. If the small piece of the patella is quite small, and its movement is what is causing the patient’s symptoms, then excision of the small piece may help. If the bipartate patella has two pieces that are basically the same size, then treatment of a symptomatic one is much more difficult. The take out half of the patella would cause quite a few problems. So, sometimes, trying to get the two halves to unite is tried. But, this has its own set of problems.
But, back to loose bodies: if a patient has a symptomatic loose body, the first thing is trying to find it; making sure that it is a loose body that is causing the “locking” and not something else (such as a meniscal tear in the knee).
Once a loose body has been identified, then it is usually recommended that it be removed, to try to reduce the chances of causing damage to the articular surfaces in the joint. Continued locking and snapping over the body can cause wear and tear damage to the cartilage, just like a pebble within a mechanical joint.
The usual way to remove a loose body in the knee is through the use of arthroscopy instruments. But, it is not as easy as it sounds. It can sometimes be quite a chore chasing the little thing down. Then, just as you go to grab the little thing, it moves out of your camera view or away from your grabber. You usually have to try to skewer the thing with a long meniscal needle, then grab it. It can be quite a game of “hide and seek” sometimes.
So, again, the first thing is to make sure that it is a loose body that is causing the problem. If you have had an MRI or CT scan done on the knee within the recent past, it can be reviewed to see if a loose body is present on the study. It usually takes a while for a loose body to reach a size sufficient to cause locking, unless you have had trauma since the study, in which a piece of bone or cartilage could have been knocked off.
If a loose body is identified, and it is causing symptoms of locking, it is usually recommended that it be taken out.
You should discuss this with your surgeon. Good luck.
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