Loss of anterior cruciate ligament integrity and the development of radiographic knee osteoarthritis: a sub-study of the osteoarthritis initiative.
INTRODUCTION
The aim of this study was to determine whether loss of ACL integrity in an older cohort precedes the onset of radiographic OA (ROA).


METHODS
Participants in this nested case-control study were selected from the Osteoarthritis Initiative (OAI) study who had risk factors for OA development but did not have ROA (Kellgren-Lawrence grading (KLG) of 0 or 1) in both knees at baseline. The MRIs were assessed for the presence of ACL tears. Case knees were defined by the development of ROA on knee radiographs between the 12 and 48 month visits. Their radiographs were assessed at P0 (time of onset of radiographic knee OA), 1 year prior to P0 (P-1) and at baseline. Controls were selected from amongst those who did not develop incident ROA and were matched to cases.


RESULTS
355 persons who developed ROA were matched to 355 controls. No relationship between loss of ACL integrity and incident ROA was found at any assessment time point. Odds ratios (OR) for baseline, 1 year prior to incident ROA (P1) and at point of occurrence of incident ROA (P0) were 2.00 (0.66-6.06), 2.5 (0.76-8.24) and 2.75 (0.85-8.88) respectively. A significant risk of incident ROA was found in participants who had a history of knee injury with an OR of 1.51 (1.05-2.16).


CONCLUSION
Loss of ACL integrity does not confer a significantly increased risk of incident ROA in an older adult cohort. In contrast, a history of knee injury was associated with an increased risk of incident ROA.
['Johnson|V L|VL|', 'Kwoh|C K|CK|', 'Guermazi|A|A|', 'Roemer|F|F|', 'Boudreau|R M|RM|', 'Fujii|T|T|', 'Hannon|M J|MJ|', 'Hunter|D J|DJ|']
D000368:Aged D000070598:Anterior Cruciate Ligament Injuries D016022:Case-Control Studies D005260:Female D006801:Humans D007718:Knee Injuries D008137:Longitudinal Studies D008279:Magnetic Resonance Imaging D008297:Male D008875:Middle Aged D020370:Osteoarthritis, Knee D011859:Radiography D012307:Risk Factors D012720:Severity of Illness Index
Incidence Anterior cruciate ligament (ACL) Magnetic resonance imaging (MRI) Osteoarthritis (OA)