Inflammation of the Bags or membranes.

Within traumatic pathology, knee joint is probably the most studied, the pioneer in the field of arthroscopy, as mentioned before, it is a very important joint since it is in constant burden there are no bones that limit it; all boundaries are of soft tissue.

It is wholly surrounded by a joint capsule, forming a closed space. The inner cover of the capsule is the synovial membrane, whose primary mission is the secretion of fluid by the same name, which is fundamental to joint physiology with the purpose of lubrication and defense.

The excess secretion results in synovial accumulation causes increased inter-articular pressure and generates the disturbing and known spill (Figure. 32).

Figure. 32. a cross section of the knee. Note the presence of synovial fluid and an irritated of inflamed membrane.

There are several underlying causes of this excess

The main villonodular, abnormal growth of the lining of the jacket cover, therefore disproportionately thickened can be filled within the joint (between the surfaces of the tibia and femur) impeding the movement between the two surfaces.

Especially affects young people., These problems are of unknown origin. Other causes of inflammation of the membranes are bags or inflammatory diseases, non-specific synovitis and rare diseases but are existing as chondromatosis, the osteochondromatosis, hemangioesclerosis and desmoid tumors.

If you have a knee that increases in volume, and severe pain you may have a synovial problem, an MRI must be done before consultation (Figure. 33).

Figure. 33. MRI shows knee. The white mass indicated corresponds to inflammation of the synovial.

Laser Surgery

Treatment without open surgery, has shown its benefits, in general, greater recovery is obtained, ability to walk the same day of surgery, within 3 days ability to drive a car, about a week after to work and a little over two weeks physical activity.

Baker's cyst or popliteal cyst

Baker's cyst is a fluid-filled formation which is located in the back of the knee or popliteal fossa. Also known as popliteal cyst. In the back of the knee (popliteal) there are many bags that serve to facilitate the sliding of the tendons that pass through the area. These bags are frequently irritated, inflamed and enlarged producing Baker's popliteal cyst. As shown in Figure 34

Figure 34 Magnetic Resonance in blue indicating a popliteal cyst.

Its origin

What causes excessive production of synovial fluid is a problem caused by intra-articular and meniscal injury, a problem of osteoarthritis or rheumatoid arthritis. Knees and all joints have a lubricant called synovial fluid. This fluid acts as hinge oil, reducing friction. When there is a problem in the joint, it reacts by producing more liquid, this is called effusion. The excess fluid builds up in the back of the knee, causing the cyst as in Figure 35.

Figure 35 Accumulation of lubricant (synovial fluid) producing joint effusion.

What are the symptoms Baker's cyst?

If it is small, it may not cause any symptoms. When the cyst is large it causes pain and discomfort to the patient when extending the knee. It is important to emphasize that you have to differentiate whether the pain is due to Baker's cyst, or if due to a torn meniscus, arthritis or complications associated with the cyst, as shown in Figure 36.

Figure 36. shows pain and discomfort to extend the knee.

How is Baker's cyst treated?

If the cyst is not painful, requiring only observation and reassurance through an accurate diagnosis. If a sensation of weight is felt, a syringe placing a small dose of steroid, although it may reproduce. If it is caused by an intra-articular pathology such as meniscal injury, there should be knee arthroscopy. Do not operate only the cyst, because if more intra-articular problems are manifested, and are left untreated, the cyst reoccurs.

We recommend the removal of it with Holmiun Yag laser without open surgery. Although in some cases a small scar may be required, as shown in Figure 37.

Figure. 37. Noninvasive treatment of popliteal cyst.

Post surgery

After the intervention you will support your foot immediately beginning post-operative recovery. Range of motion can be done when the wound is stable, weight bearing is allowed in the knee as soon as the patient can tolerate it.