Impaired Knee Joint Position Sense in Chronic Patellar Tendinopathy Is Associated with Kinesiophobia but Not Central Sensitization

Background: Patellar tendinopathy is a common musculoskeletal condition that may impair functional performance and limit physical activity. While structural and mechanical factors have been widely investigated, the role of proprioceptive function and its interaction with behavioral and central pain-related mechanisms remain unclear. This study aimed to investigate the relationship between knee joint position sense, kinesiophobia, and central sensitization in individuals with chronic patellar tendinopathy. Methods: A total of 42 recreational athletes with clinically diagnosed chronic patellar tendinopathy were included in this cross-sectional study. Knee joint proprioception was assessed using joint position sense testing at multiple knee flexion angles with a continuous passive motion device. Kinesiophobia and central sensitization were evaluated using the Tampa Scale of Kinesiophobia and the Central Sensitization Inventory, respectively. Joint position sense values of the involved and contralateral extremities were compared, and correlation analyses were performed to examine associations between joint position sense and psychosocial variables. Results: The involved extremity demonstrated significantly greater absolute angular error compared to the contralateral side at higher knee flexion angles (≥60°, p < 0.01), whereas no significant differences were observed at lower angles. A moderate positive correlation was found between joint position sense error and kinesiophobia at higher flexion angles (≥30°, p < 0.01). No significant association was identified between joint position sense error and central sensitization across any of the tested angles (p > 0.05). Conclusions: Proprioceptive function is impaired in individuals with chronic patellar tendinopathy, particularly under increased mechanical demand. The association between joint position sense deficits and kinesiophobia, but not central sensitization, suggests a potential relationship between movement-related fear and sensorimotor alterations. These findings highlight the importance of incorporating proprioceptive assessment and addressing kinesiophobia in the clinical management of patellar 36 tendinopathy.