Diagnosis | Shelf Syndrome

Diagnosis

In order to diagnose a shelf syndrome, one first tries to localize the pain exactly or to determine an occurred thickening in the area of the patella.Often you can also feel the rubbing of the plica in the knee joint during movement. The soles sign is positive. In the zohlen sign, the thumb and index finger grasp the upper edge of the patella and push the patella downwards (caudalized).

If the four-headed front thigh muscle (M. quadriceps) is now tensed, the kneecap is pressed onto the lower parts of the thigh bone (femoral condyles), which is felt as painful if the cartilage is damaged. 50% of all patients generally find it very unpleasant to perform this test on them. Overall, the Shelf Syndrome is not easy to diagnose because the overlapping of other pathological lesions (rupture of the cruciate ligament, meniscus damage, etc) makes the diagnosis more difficult.

A magnetic resonance examination (imaging procedure) can also be helpful in making the diagnosis. However, it does not always have to provide a clear result. In some patients, shelf syndrome is only definitively confirmed by a knee joint endoscopy (arthroscopy). As a result, the exact clarification is almost only possible through arthroscopy. On the other hand, the diagnosis of shelf syndrome is often a diagnosis of embarrassment, if no other pathological changes in the knee joint that explain the symptoms can be detected in the case of recurring complaints in the knee joint.

Therapy

Once a shelf syndrome has been diagnosed, the severity of the disease is first assessed and then the treatment strategy is determined. In general, a distinction is made between conservative and surgical therapy. The shelf syndrome is initially treated conservatively.

It is performed with local and oral anti-inflammatory drugs (anti-inflammatory drugs). Conservative therapy also includes rest, physiotherapy with connective tissue massages and training of the often strength-reduced medial part of the four-headed front thigh muscle (Musculus vastus medialis). Cooling with ice is also helpful and relieves pain and swelling.

The local administration of anti-inflammatory injections (steroid injection) is questionable with regard to its effect in the treatment of shelf syndrome. The problem with shelf syndrome, however, when it occurs in athletic patients, is that the symptoms usually do not improve because the inflammatory altered and hardened edge of the plica continues to rub against the cartilage, destroying it. For this reason, knee endoscopy (arthroscopy) should be considered at an early stage in sports patients.

Otherwise, arthroscopy is indicated if the symptoms do not disappear with conservative therapy. In arthroscopy, the plica is removed (resected). All therapeutic instruments that are not surgical are used in this procedure.

It is important to protect the affected knee first. Overloading during sports should be avoided completely. Stress on the knee, such as jogging or hiking in the mountains, should also be avoided if possible.

Swimming and other joint-gentle measures are highly recommended. However, the leg should by no means be held in a resting position, as this is not good for the joint and also increases the risk of deep vein thrombosis. In addition to reducing the overloading, pain-relieving measures should be taken.

Physical pain treatment should be mentioned here. This includes regular treatment with ice packs, which should be placed on the knee. Physiotherapeutic measures can also be taken to relieve the knee joint as much as possible by means of appropriate exercises to build up the muscles around the knee.

Physiotherapy should be carried out regularly and care should be taken to avoid overloading the muscles. It can also be helpful to stabilize the knee during everyday movements (such as running, bending and stretching). The use of a bandage can be useful and helpful for this.

However, the knee should still be freely movable and not be too compressed. If the bandage increases the pain, the bandage should be loosened or omitted completely. The conservative treatment of shelf syndrome also includes pain management with medication.

It makes sense to combine a drug that has both pain-relieving and anti-inflammatory effects. Ibuprofen and Diclofenac are always popular in orthopedics and exert these 2 effects. Ibuprofen can be used up to a maximum of 800 mg three times a day, while diclofenac reaches its upper limit of action at 75 mg twice a day.

Note the relatively new contraindications for diclofenac.For example, patients with coronary heart disease may not receive this drug because the cardiovascular risks increase with regular use of the drug. Ibuprofen should also be used in this case only after careful consideration. If no cardiovascular risk factors have been prescribed, care should be taken to ensure that patients do not suffer from reflux or chronic gastritis as well as ulcers, as the use of diclofenac or ibuprofen inhibits the build-up of the stomach lining.

In this case the use of both drugs should only be used in combination with a gastric protection preparation. The most common proton pump inhibitors used here are pantoprazole or omeprazole. If there is no improvement in symptoms under conservative treatment, it must be considered whether surgery will lead to the desired success.

Today, the operation is performed minimally invasively and is also known as arthroscopic surgery. It can be performed under general anesthesia or by blocking the nerves of the corresponding leg. The patient is first informed about the risks of the operation.

These include bleeding that is difficult to stop, infection of the joint, wound healing disorders, allergic reactions to the anesthetic or the need to operate on the knee open due to anatomical conditions. After the patient has given consent for the operation and an appropriate anesthesia has been administered, the knee is washed with a sterile liquid. Two small skin incisions around the knee joint serve as entry points for 2 rod-shaped instruments, which are inserted into the knee joint.

One is a camera with a bright light, the other is an inlet for liquid. In addition, it can also be used to insert instruments into the knee joint, which are necessary for smoothing cartilage and for cutting and suturing. After the instruments have been inserted, a diagnostic view of the knee joint begins.

The camera delivers images in real time, which can also be recorded for documentation purposes. During the procedure, the knee is regularly bent and stretched to see whether parts of the knee become trapped during movement and thus cause pain. Once the examiner has located the plica, he or she begins the ablation.

In addition, an inserted smoothing instrument can be used to remove excess and disturbing cartilage. Sterile fluid is then pumped into the knee joint through the water inlet and immediately sucked out again. This also rinses the crushed parts of the plica out of the knee joint.

Shortly before the end of the procedure, small sutures are inserted and the joint skin is closed. Since this area is well supplied with blood vessels, it may often be necessary to stop bleeding by means of electrocoagulation. After removing the instruments, the skin incisions are sutured and sterilely connected.

The sutures can then be removed about 10-12 days after the procedure. The treatment of shelf syndrome (also known as plica syndrome, plica-shelf syndrome) is often performed conservatively. Anti-inflammatory measures are used to try to reduce the painful conditions of a shelf syndrome.

Furthermore, a treatment approach through physiotherapy is often attempted. If there is no improvement of the symptoms, a surgical procedure should be considered. The surgical procedure can either be performed under general anesthesia or through a nerve block where the patient is conscious but does not feel pain during the procedure on the knee.

In the past, such operations were performed exclusively on the open knee. Today, the minimally invasive procedure is mainly chosen, which is also called arthroscopy or arthroscopy. The knee endoscopy is seen as a diagnostic measure as well as a therapeutic measure.

If imaging procedures such as magnetic resonance imaging of the knee can provide a fairly reliable diagnosis in cases where shelf syndrome is suspected, then a knee joint endoscopy can provide the final proof. During arthroscopy, two small skin incisions are made on the previously disinfected knee joint, through which an instrument with a camera is then inserted. Through the other skin incision, another instrument is pushed, which has an irrigation device, but also an inlet that allows other instruments, such as sutures and forceps, to be introduced into the knee joint.

The knee is brought to a 90 degree angle before the operation on a lying patient. The two instruments are then inserted into the joint gap through the skin incisions made.With the help of the camera and the bright light source attached to it, the knee can then be inspected and the position of the ligaments and cartilage as well as the space available can be assessed. Sterile fluid can be pumped into the knee joint with the help of the irrigation device and then sucked out again.

Cartilage that protrudes into the joint space can be smoothed and removed with an additionally inserted instrument. During the examination it is important not to keep the knee in a static position but to move it back and forth on the lying patient by bending and stretching it. This is the only way to ensure that the examination can also see the corresponding space conditions during normal knee movement.

During this maneuver, in the case of a shelf syndrome, it is also possible to determine whether a plica is located in the area of the knee joint in an extended manner. During the entire procedure, the camera can be used to take pictures and video recordings for documentation purposes. Once a shelf syndrome has been reliably diagnosed by this procedure, the diagnostic procedure is complete and the therapeutic procedure begins.

The plica is then removed piece by piece. For this purpose, a so-called burr is now inserted through a skin incision into the knee joint. This removes the inner skin of the knee in the area that is fibrosed and inflammatory processes become visible.

The ablation is performed in this area down to the capsule. The ablated material can be removed from the knee using small forceps and suction devices. In contrast to the menisci, the joint skin is well interspersed with blood vessels.

For this reason, moderate to heavy bleeding may occur during the procedure, which must then be stopped by so-called electrocoagulation or injection. For this reason, it is important to clarify in advance whether the patient is taking blood-thinning medication such as ASA or Marcumar. These must then be discontinued accordingly before such an operation.

After the knee has been sutured, the instruments are removed from the knee and the open wound at the knee joint is closed with a skin suture. After the skin wounds have been sterilely dressed, the patient is transferred from the operating room to the normal ward. The procedure takes between 20 minutes and one hour.

In very rare cases, it may be necessary to continue the operation, which was initially started arthroscopically, open. This is particularly necessary if anatomical conditions in the knee joint do not allow an adequate view through an arthroscopy or if severe bleeding that occurs during surgery cannot be stopped arthroscopically. The operation is a routine procedure in orthopedics.

However, complications can also occur here. In addition to unstoppable bleeding during the operation, wound healing disorders and infections in the area of the wound can also occur after skin closure. In rare cases, infections of the knee joint can also occur despite very sterile work.

This very dreaded complication must be treated immediately with antibiotics. If no corresponding effect can be achieved, the knee may have to be reopened surgically. In this case, local antibiotic measures (e.g. insertion of antibiotic-coated chains) would be possible in addition to sterile irrigations.