Why does the patella dislocate laterally?
Patellar dislocations tend to occur in a lateral direction, partly because the direction of pull of the quadriceps muscle is slightly lateral to the mechanical axis of the limb. Medial instability is rare and more likely to result from congenital conditions, quadriceps atrophy, or iatrogenically.
What is a transient lateral patellar dislocation?
The patella becomes unstable and undergoes a transient, violent lateral displacement. During this dislocation phase of injury, shearing forces can damage the articular surfaces of either the patella or the lateral femoral condyle.
What is lateral patellar instability?
Subluxation or lateral translation will involve a transient lateral movement of the patella. In general, it is early in knee flexion such that the patient will experience a feeling of pain or instability. This form of patellar subluxation is rather a recurrent dislocation of the patella.
What is a laterally tilted patella?
In the painful knee there is a tendency for the patella to tilt toward the outside of the knee. This occurs because of the chronic pull of the knee cap to the outside by the thigh muscles, creating a strain on the medical or inside tissues (the retinaculum).
What prevents the patella from dislocating laterally?
The articular cartilage on the medial facet is thicker than on the lateral facet, with the lateral facet bigger than the medial. It has an anterior projection on the lateral femoral condyle, lateral to the patellar groove. This prevents lateral dislocation of the patella.
What are signs of a dislocated knee?
Symptoms of a dislocated kneecap
- a “popping” sensation.
- severe knee pain.
- being unable to straighten the knee.
- sudden swelling of the knee.
- being unable to walk.
Where is the lateral patellar facet?
Lateral articular facet (facies articularis lateralis) is the larger of two shallow depressions on the posterior surface of the patella, which articulates with the lateral condyle of femur.
What prevents lateral dislocation of patella?
How is patellar subluxation diagnosed?
To diagnose a patellar subluxation, your doctor will bend and straighten the injured knee and feel the area around the kneecap. X-rays may be used to see how the kneecap fits into the groove at the bottom of the patella and to identify any other possible bone injuries.
How do you test for patella dislocation?
Starts here2:11Patellar Apprehension Test | Patella Dislocation – YouTubeYouTube
What structure causes the patella to track laterally?
The VMO more oblique pull on the patella stabilizes the patella against excessive lateral pull. Lateral tracking is guided by both the vastus lateralis and the iliotibial band. Patellar motion is further constrained by the patellofemoral ligament, the patellotibial ligament, and the retinaculum.
How do you assess patellar tilt?
Starts here0:46Patellar Tilt Test – YouTubeYouTube
What is the recovery time for a patellar tendon rupture?
Full recovery can take from 6 months to a year. It depends on how healthy you were before and how much effort you put into the process. You should plan for at least a week off work if you have a desk job and 4 to 6 months if you do manual labor.
How long does a dislocated patella take to heal?
A dislocated kneecap is a common injury that normally takes about 6 weeks to heal. It’s often caused by a blow or a sudden change in direction when the leg is planted on the ground, such as during sports or dancing. The kneecap (patella) normally sits over the front of the knee.
What is patellar displacement?
A patellar dislocation is a knee injury in which the patella (kneecap) slips out of its normal position. Often the knee is partly bent, painful and swollen. The patella is also often felt and seen out of place.
What is Patellar subluxation?
The patella, or kneecap, is a small bone on the front of the knee joint. Patellar subluxation occurs when the tendons that stabilize the kneecap abnormally slip out of place. This condition, which is also referred to as a partial patellar dislocation, typically occurs following traumatic injury to the knee joint.