age (girls younger than 10 years, boys younger than 12 years) is a very significant predictor for development of a contralateral slip PATELLOFEMORAL PAIN SYNDROME AND CHONDROMALACIA PATELLAE Current Evidence Patellofemoral pain syndrome describes a constellation of symptoms, principally anterior knee pain, arising from the patellofemoral joint Chondromalacia patella is a pathologic diagnosis referring to damage of the articular cartilage of the patella Specific changes include softening, fissures, and erosions Whether the two conditions are actually related is the subject of debate They share a number of symptoms and precipitating factors Patellofemoral pain syndrome may represent the early end of the spectrum of injury, which ultimately may or may not progress to true pathologic changes within the cartilage Patellofemoral pain syndrome is first seen in early adolescents, especially in runners The rise in incidence tends to parallel the growth spurt A number of underlying causes or associated factors have been identified Malalignment of the patella and an abnormal tracking of the patella over the femoral condyles appear to be the major contributors to patellofemoral disorders The quadriceps or Q angle is the angle between a line from the center of the tibial tubercle to the center of the patella and a second line from the center of the patella to the anterior superior iliac spine A Q angle greater than 20 degrees has been found in a significant number of affected individuals and results in disproportionate lateral traction applied to the patella during extension The wider pelvic bones in females result in a generally wider Q angle, which may account for the higher proportion of patellofemoral problems in females Relative weakness of the vastus medialis is highly associated with the condition and strengthening of this muscle through rehabilitation is associated with clinical improvement A shallow femoral intracondylar sulcus has also been associated with the disorder Clinical Considerations Clinical Recognition Patellofemoral pain syndrome is often classified as an overuse syndrome because individuals exposed to repetitive trauma are at higher risk for this disorder Runners are particularly predisposed to develop this condition especially those running hills or stadium stairs Poor training regimens, rapid increases in duration