excessive lateral pressure syndrome
Excessive lateral pressure syndrome (ELPS) or patellar compression syndrome is the abnormal lateral tilt of the patella without lateral translation and considered one of the relatively common causes of anterior knee pain.
Epidemiology
It can affect both adolescents and adults.
Clinical presentation
Patients usually present with insidious onset anterior knee pain aggravated by physical activity.
Pathology
ELPS is due to an imbalance between medial and lateral dynamic stabilizers, either secondary to more common abnormally tight lateral retinaculum/vastus lateralis or lax medial retinaculum/vastus medialis. This results in a lateral tilt of the patella without obvious subluxation or dislocation. In fact, in some cases, even slight medial translation can be present. Over time, chronic impaction of the lateral patellar facet to the lateral femoral trochlea ensues chondral damage and osteoarthritis.
Radiographic features
Abnormal tilt can be measured by the patellofemoral angle with a medial opening of the angle or an angle <8° is diagnostic of ELPS in an appropriate clinical setting.
Siehe auch:
