- Dislocation of the patella: a common knee injury
The patella and its functions
The patella, or kneecap - this is the biggest sesamoid (sesamoid - a bone of oval, located in the interior of the tendon and is usually lying on the surface of another bone) human bone, located deep in the quadriceps tendon. When the muscles of the knee performs assignment block, whereby the power of the muscles increases. He also warns of the knee injury.
The patella is well detectable through the skin and a bone, the upper rounded edge is called the base and the lower edge of the few stretches and forms the top of the knee pads.
The front surface of the patella is rough, it covers the periosteum, the back or smooth articular surface, covered with cartilage. Vertically Aligned comb back surface of the patella divides into two parts: the lower inner and outer larger, which in turn are attached to the surface of the femur forming a knee joint.
Top to the patellar tendon attaches the quadriceps muscle, below - the patellar tendon, which then attaches to the tibia. In addition to the patellar tendon hold two vertical and two horizontal supporting ligament. Vertical bundles are a continuation of the quadriceps femoris tendon, patella cover on both sides and are attached to the tibia firmly grow together with the joint capsule. Horizontal ligament firmly connected to the lower leg fascia beams and fascia lata.
Blood supply and innervation of the patella by a network of blood vessels and nerves located under the fascia.
Causes of patellar dislocation and their types
Traumatic dislocation of the patella is divided into acute and habitual. In addition, there are full of dislocations and subluxations. There traumatic patellar dislocation is most often a result of falling on one knee when you hit it with a hard object or change the thrust of muscles - the extensor tibia. Great value for the dislocation has a number of predisposing factors: the deviation of the lower leg outwards, a more developed internal condyle of the femur and the wrong direction quadriceps against the patellar tendon.
When traumatic patellar dislocation occurs laterally offset with rupture of the joint capsule. Lateral displacement of the patella promotes bleeding into the joint cavity, stretching of the capsule and a decrease in muscle tone. When patellar dislocation is outward from the outer convexity (condyle) of femur, if it is located anterior subluxation of this condyle.
Acute traumatic patellar dislocation
In acute patellar dislocation knee bent and extended in the transverse direction on the outer side surface of the patella is felt, quadriceps tendon and patellar tendon tense. Patellar dislocation is accompanied by bleeding into the joint (hemarthrosis) or effusion in the joint fluid, sharp pain and restriction of movement. Leg bent at the knee and lower leg rotated outwards.
The presence of dislocation is confirmed by radiological studies.
Once the diagnosis under local or general anesthesia is performed closed reduction of dislocation. For this leg bent at the hip and then grab the edge of the patella thumbs of both hands and slowly pulled his strong front, slipping to its original place. The liquid is removed from the joint syringe. After this limb is fixed in extension for three weeks. From the first days of the victim must be actively exercise the thigh muscles, periodically reducing them and picking up pace. A week later allowed to walk with crutches, slightly stepping on the foot. After two or three weeks, remove the plaster cast, and the victim can walk completely loading the leg.
With rarely a so-called horizontal sprains knee pads when it is located between the articular surfaces of the femur and tibia, shows early surgical treatment. In such cases, the kneecap is removed from the joint, patellar ligament sutured, postoperative limb fixed plaster cast for three weeks.
Familiar traumatic patellar dislocation
Traumatic dislocation of the patella can be repeated and become familiar, especially if the outer protuberance (condyle) of femur as a result of a congenital deformation has a chamfered surface of the joint.
When habitual dislocation
Habitual dislocation - that kind of attack you pursue?
patella in the early stages may conservatively (without surgery) treatment - fixing plaster cast, physiotherapy and massage. If habitual dislocation does not give in to conservative treatment, surgery is shown. Performed plastic surgery on the joint capsule and the tendons of the extensor muscles, the purpose of which - the weakening of the thrust of the patella on the outside.