title: Correlation between Ahlbäck radiographic classification and anterior cruciate ligament status in primary knee arthrosis.
abstract: OBJECTIVE
  To correlate the Ahlbäck radiographic classification with the anterior cruciate ligament (ACL) status in knee arthritis patients.
  
  
  METHODS
  The study evaluated 89 knees of patients who underwent total knee arthroplasty due to primary osteoarthritis: 16 male and 69 females, with mean age 69.79 years (53-87 years). Osteoarthritis was classified radiographically by the Ahlbäck radiographic classification into five grades. The ACL was classified in the surgery as present or absent. The correlation of ACL status and Ahlbäck classification was assessed, as well as those of ACL status and the parameters age, gender, and tibiofemoral angulation (varus-valgus).
  
  
  RESULTS
  In cases of varus knees, there was a correlation between grades I to III and ACL presence in 41/47 (86.7%) cases and between grades IV and V and ACL absence in 15/17 (88.2%) cases (p< 0.0001). In valgus knees, no statistically significant correlation was observed between the ACL status and the Ahlbäck classification. In the present study, absence of the ACL was more common in men (9/17; 52%) than in women (19/72; 26%).
  
  
  CONCLUSIONS
  In cases of medial osteoarthritis, the Ahlbäck radiographic classification is a useful parameter to predict ACL status (presence or absence). In gonarthritis in genu valgum, ACL status was not predicted by Ahlbäck's classification.
authors.affiliation: Hospital Federal de Ipanema, Serviço de Ortopedia e Traumatologia, Rio de Janeiro, RJ, Brazil.
authors.forename: Glaucus Cajaty
authors.initials: GC
authors.lastname: Martins
authors.affiliation: Universidade de São Paulo, Faculdade de Medicina, Departamento de Ortopedia e Traumatologia, São Paulo, SP, Brazil.
authors.forename: Gilberto Luis
authors.initials: GL
authors.lastname: Camanho
authors.affiliation: Hospital Federal de Ipanema, Serviço de Ortopedia e Traumatologia, Rio de Janeiro, RJ, Brazil.
authors.forename: Leonardo Marcolino
authors.initials: LM
authors.lastname: Ayres
authors.affiliation: Hospital Federal de Ipanema, Serviço de Ortopedia e Traumatologia, Rio de Janeiro, RJ, Brazil.
authors.forename: Eduardo Soares de
authors.initials: ES
authors.lastname: Oliveiras
keywords: Anterior cruciate ligament; Arthroplasty, knee; Knee arthrosis