Correlation of Toe Grip Strength among Individuals with Knee Osteoarthritis with and without Fear of Pain: A Cross-sectional Study

Introduction: Knee Osteoarthritis (OA) is a common degenerative joint disease that affects millions of people worldwide. It is characterised by progressive loss of joint cartilage, resulting in pain, stiffness, and significant disability, leading to a reduced quality of life. Fear of pain is a significant psychosocial factor that affects individuals with knee OA, leading to decreased physical activity. However, the relationship between Toe Grip Strength (TGS) and fear of pain in individuals with knee OA is poorly understood, even though fear of pain has been known to impact strength in both the upper and lower limbs. Aim: To examine the correlation between fear and TGS among individuals with knee OA, both with and without fear of pain. Materials and Methods: This cross-sectional study was conducted at the Department of Physiotherapy, Nitte Institute of Physiotherapy, affiliated with the University of Mangalore, Karnataka, India, from April 2022 to March 2023. The study included 60 individuals, with 30 in each group, diagnosed with knee OA using the Kellgren and Lawrence (KL) grading system (grade 2 and above). The participants, both men and women aged between 45 and 80 years, were informed about the study's purpose. The Fear Avoidance Belief Questionnaire (FABQ) form was completed by the screened patients, who were then divided into fear and non fear groups. Body Mass Index (BMI) was determined by measuring height with a wall-mounted device and weight using a traditional analog scale. TGS was evaluated in both groups using a pinch grip dynamometer. The Pearson correlation coefficient was used for data analysis, with a p-value <0.05 considered statistically significant. Results: The results of the current study indicated that the FABQ showed a negative correlation (p-value >0.05) with TGS (both right and left-side) (r:-0.296 (right) and-0.302 (left)), and a positive correlation (p-value<0.05) with the Numerical Pain Rating Scale (NPRS) (both during activity and at rest). Conclusion: This study revealed a significant association between fear and TGS in individuals with knee OA. Notably, Fear Avoidance Beliefs (FAB) exhibited a negative correlation with TGS while demonstrating a positive correlation with pain levels.