Buckling in the Iranian Patients with Knee Osteoarthritis: Its Frequency and Correlation with Physical Activities and Falling

Document Type: Original Article


1 Associate Professor, Sports Medicine Department, Iran University of Medical Sciences, Tehran, Iran

2 M.D. Iran University of Medical Sciences, Tehran, Iran

3 Assistant of Sports Medicine, Sports Medicine Department, Iran University of Medical Sciences, Tehran, Iran


Introduction:Knee osteoarthritis (KOA), one of the most common articular diseases, sometimes leads to severe disability. This study aimed to estimate the prevalence of knee-buckling in patients with KOA during the past three months and to investigate its relation with the physical function.
Methods:A cross-sectional study was performed on 190 patients with KOA. Two checklists and WOMAC questionnaire were completed by the participants. The patients’ function was evaluated by timed up and go (TUG) and six-minute walk tests (6MWT). Comparison between the two groups of patients with and without buckling was done using independent t-test and the correlations were analyzed between the variables using K square and Pearson correlation tests.
Results:Eighty three patients (43.68%) had a history of buckling in the past 3 months. Knee-buckling frequency was 40.87% and 48% in women and men, respectively. Statistical analysis showed significant differences between pain (p = 0.007), TUG (p =0.0001), 6MWT (p = 0.0001), WOMAC pain (p= 0.005), WOMAC stiffness (p = 0.006) and total WOMAC scores (p=0.03) concerning the two groups with and without buckling. There was a significant correlation between buckling with gender (ρ= 0.72, p=0.025), KOA history (p=0.67, p= 0.033) and the rate of fall (ρ=0.87, p=0 .012). Moreover, there were reverse significant correlations between the history of buckling with WOMAC score (r= - 0.51, p=0.02) and the functional tests results including TUG (r= - 0.57, p=0.0001) and 6MWT
(r= - 0.67, p=0.0001).
Conclusion:The results indicated a prevalence of 43.68% buckling among the patients which was associated with their functional impairment.


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