Background/Purpose: Approximately 14 million people in the United States have been clinically diagnosed with symptomatic knee OA. Rising from a chair, negotiating stairs and walking can be compromised. Exercise, a widely recommended first line treatment to improve pain and daily function among adults with OA is underutilized. Thus, identifying factors that restrict movement and exercise among adults with knee OA is critical. Kinesiophobia, or fear of movement due to pain and potential physical harm, has been proposed to be an important factor restricting movement and willingness to perform exercise among adults with chronic pain, however it’s relationship with painful knee OA is not well understood. This study examined the relationship of kinesiophobia with commonly used knee osteoarthritis performance-based measures before and after an evidence-based exercise class.

Methods: We used secondary data analysis from a randomized controlled trial before and after a 6-week group strength training class that met twice weekly for 1 hour. Participants were ≥50 years with knee pain and self-reported doctor diagnosed knee OA. Kinesiophobia was measured using the 17-item Tampa Scale of Kinesiophobia (TSK).  Performance measures included timed-up-and-go (TUG), sit-to-stand 5 and 10 repetitions, and negotiation of 10 steps. We measured quadriceps strength with isokinetic testing, and pain and function with the WOMAC. For data analysis we used simple linear regression with TSK, or change in the TSK, being the independent and performance measures, or their changes, as the dependent variable, and paired T-tests.         

Results: 68 participants had baseline data of which 55 had after exercise class data. Higher TSK was associated with slower stair climb (p=0.02) and time in the 5 sit-to-stand (p=0.03) at baseline. TSK decreased after the exercise class (mean change -0.58) but did not attain statistical significance (p=0.47). Change in TSK was associated with change in self-reported physical function (p=0.02), but not with pain or physical performance measures.

Conclusion:  Among this cohort of adults with knee osteoarthritis, kinesiophobia was associated with negotiating stairs and rising from a chair, two critically important functional activities commonly restricted by osteoarthritis. Future research addressing the impact of kinesiophobia and efficacy of interventions to modify said impact is warranted.

Table 1. Simple linear regression baseline variables

*adjusted for age, sex and pain

Table 2. Simple linear regression of change scores before and after exercise class