Brief fear of movement scale for osteoarthritis

Fear of movement, or kinesiophobia, is described as a debilitating fear of physical movement and activity that an individual believes will cause pain, injury, or re-injury1. Fear of movement has been studied in diverse patient populations (e.g., chronic low back pain, chronic fatigue syndrome) and has been associated with increased pain, physical disability, and psychological disability2. Recent experimental data suggest that pain-related fear of movement and avoidance can be acquired through associative learning3. In patients with osteoarthritis (OA), maintaining a sufficient level of daily activity is critical to managing pain and disability associated with the disease4, but individuals who experience fear of movement may be hesitant to initiate or engage in daily activity. Fear of movement has important clinical implications for individuals with OA5–9 and is increasingly a target of interventions aimed at reducing OA-related disability10,11. Several studies have demonstrated the negative impact of fear of movement on individuals with OA5–9. In a recent study6 in knee OA, fear of movement was significantly associated with greater psychological disability and slower gait speed after accounting for demographic and medical variables. Another study7 in OA indicated that fear of movement explained a significant proportion of variance in physical disability after controlling for pain and radiographic findings. The lack of a validated fear of movement scale for OA, measurement problems, and the length of existing scales limit the widespread assessment of fear of movement in OA. Because the validity of a measure is dependent on the specific population being examined12, determining the appropriate structure and content of a fear of movement scale for OA is necessary. Findings from other samples of patients with persistent pain may not apply to OA. Beliefs about pain and movement may differ across populations and healthcare providers’ recommendations regarding physical activity could vary based on medical diagnosis13. Fear of movement scales designed for other populations (e.g., chronic pain, accident-related injury) may not be appropriate for use in OA. Disease-related pain due to OA usually occurs gradually over time, does not necessarily occur in response to a specific event or accident, and may worsen over time due to disease progression. The present study was conducted to establish a brief fear of movement scale for use in OA. Items from the most widely used measure of fear of movement, the Tampa Scale for Kinesiophobia (TSK)14, were examined. The measurement properties of the TSK have been evaluated in patients with chronic and acute back pain15–23, fibromyalgia16,17,24, and musculoskeletal pain13,19. Two relatively small studies have examined the properties of the TSK in OA7,25, but these studies reported conflicting findings. Heuts and colleagues7 used confirmatory factor analysis to compare various structures of the TSK in individuals with OA and found a two factor structure. However, several TSK items did not perform well and exhibited low factor loadings. In another OA sample, Mielenz et al.25 found a one factor solution for the TSK. Item response theory analyses showed that one item (item 13) that was retained in the Heuts et al.7 study performed poorly and the authors recommended dropping it from the scale. Given conflicting findings across these two studies, the TSK dimensions and items appropriate for use in OA remain unclear. The present study included a large (N=1,136) community-based sample of African American and White men and women with OA of the hip or knee. This study examined the number and content of the dimensions of the TSK in an OA sample, identified a brief fear of movement scale for use in OA, and tested the convergent validity of the identified fear of movement scale.