title: Acute patellar dislocation in children: incidence and associated osteochondral fractures.
abstract: In a prospective two-year study on urban (city of Helsinki) Finnish children, 72 acute patellar dislocations were observed. The calculated annual incidence rate was 43/100,000 in children under 16 years. A total of 28 knees (39%) had associated osteochondral fractures. These fractures comprised 15 capsular avulsions of the medial patellar margin and 15 loose intra-articular fragments detached from the patella and/or lateral femoral condyle. The intra-articular fragments were found only after spontaneous relocation of the patella. The femoral fracture constantly involved the edge of the articular surface in the middle third of the condylar arc.
authors.affiliation: Department of Surgery, Aurora Hospital, Helsinki, Finland.
authors.forename: Y
authors.initials: Y
authors.lastname: Nietosvaara
authors.forename: K
authors.initials: K
authors.lastname: Aalto
authors.forename: P E
authors.initials: PE
authors.lastname: Kallio
mesh_terms: D000293:Adolescent; D002648:Child; D005260:Female; D005387:Finland / Q000453:epidemiology; D050723:Fractures, Bone / Q000150:complications; D006801:Humans; D015994:Incidence; D004204:Joint Dislocations / Q000150:complications / Q000453:epidemiology*; D007718:Knee Injuries / Q000453:epidemiology*; D008297:Male; D010329:Patella / Q000293:injuries*; D011446:Prospective Studies