The Correlation of Supra Patella Effusion With Pain and Disability in Patients With Knee Osteoarthritis

Objectives: The present research aimed to evaluate the relationship of supra patella effusion with pain and disability in patients with knee osteoarthritis by Ultrasonography (US). Methods: In a cross-sectional study, 60 patients with knee OA (Mean±SD score of body mass index: 29.81±5.64 kg/m2 and age: 50.48±7.57 years) were selected by nonprobability sampling method. Supra patella effusion was evaluated using an US. All study subjects completed the Visual Analogue Scale (VAS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) for pain and disability outcomes, respectively. To evaluate the relationship between effusion, disability, and pain, the Pearson’s correlation coefficient was employed.  Results: There was a poor but significant relationship between the area of effusion (r=0.27, P=0.03), the thickness of effusion (r=0.32, P=0.01), with pain. No correlation was found between the trace of effusion (r=-0.08, P=0.5) and pain. The area of effusion (r=0.1, P=0.17), the thickness of effusion (r=0.08, P=0.51), and the trace of effusion (r=0.0, P=0.9) were not correlated with disability.  Discussion: The effusion of supra patella was slightly correlated with pain. In contrast, the effusion of supra patella demonstrated no correlation with disability.