Plica syndrome is a condition that occurs when a ''plica'' (a vestigial extension of the protective synovial capsule of usually the

knee In humans and other primates, the knee joins the thigh with the leg and consists of two joints: one between the femur and tibia (tibiofemoral joint), and one between the femur and patella (patellofemoral joint). It is the largest joint in the hu ...

) becomes irritated, enlarged, or inflamed.

Cause

This inflammation is typically caused by the plica being caught on the

femur The femur (; ), or thigh bone, is the proximal bone of the hindlimb in tetrapod vertebrates. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates with ...

, or pinched between the femur and the

patella The patella, also known as the kneecap, is a flat, rounded triangular bone which articulates with the femur (thigh bone) and covers and protects the anterior articular surface of the knee joint. The patella is found in many tetrapods, such as m ...

. The most common location of plica tissue is along the medial (inside) side of the

. The plica can tether the patella to the femur, be located between the femur and patella, or be located along the

femoral condyle The lower extremity of femur (or distal extremity) is the lower end of the femur (thigh bone) in human and other animals, closer to the knee. It is larger than the upper extremity of femur, is somewhat cuboid in form, but its transverse diameter is ...

. If the plica tethers the patella to the femoral condyle, the symptoms may cause it to be mistaken for

chondromalacia Chondromalacia patellae (also known as CMP) is an inflammation of the underside of the patella and softening of the cartilage. The cartilage under the kneecap is a natural shock absorber, and overuse, injury, and many other factors can cause in ...

. The plica themselves are remnants of the fetal stage of development where the knee is divided into three compartments. The plica normally diminish in size during the second trimester of fetal development, as the three compartments develop into the synovial capsule. In adults, they normally exist as sleeves of tissue called synovial folds. The plica are usually harmless and unobtrusive; plica syndrome only occurs when the synovial capsule becomes irritated, which thickens the plica themselves (making them prone to irritation/inflammation, or being caught on the femur).

Diagnosis

If the plica tethers the patella to the femoral condyle, the symptoms may cause it to be mistaken for chondromalacia patellae. Diagnosis is often complicated by the thin structures of plicae, fenestrated septum or unfenestrated septum all being too fine to resolve well even in MRI.

Treatment

Plica syndrome treatment focuses on decreasing inflammation of the synovial capsule. A

nonsteroidal anti-inflammatory drug Non-steroidal anti-inflammatory drugs (NSAID) are members of a therapeutic drug class which reduces pain, decreases inflammation, decreases fever, and prevents blood clots. Side effects depend on the specific drug, its dose and duration of ...

(NSAID) is often used in conjunction with therapeutic exercise and modalities.

Iontophoresis Iontophoresis is a process of transdermal drug delivery by use of a voltage gradient on the skin. Molecules are transported across the stratum corneum by electrophoresis and electroosmosis and the electric field can also increase the permeability ...

and phonophoresis have been utilized successfully against inflammation of the plica and synovial capsule. Failing these, surgical removal of the plica of the affected knee may be necessary.

References

External links

{{Soft tissue disorders Knee injuries and disorders Syndromes Rheumatology

Cause

Diagnosis

Treatment

See also

References

External links