The etiology of patellofemoral pain in young, active patients: a prospective study.

In a prospective clinical examination of 78 knees in 60 young patients with patellofemoral pain, pain occurred frequently in the lateral peripatellar retinaculum, sometimes in association with milder, less well defined medial patellar discomfort. Patellofemoral pain in the young person is frequently a soft tissue problem initially, but aberrant mechanics (particularly lateral tracking) that cause this retinacular overuse and pain may eventually lead to synovial irritation and chondromalacia. Chondromalacia, however, may not be the primary cause of patellofemoral pain in many young people.