Robotic assessment of proprioception in individuals with patellar tendinopathy: A feasibility and pilot study

BACKGROUND: Individuals with patellar tendinopathy often exhibit impaired proprioception, which may contribute to symptom persistence and injury recurrence. A parallel robotic system based on a musculoskeletal knee model has shown valid and reliable performance for assessing joint position sense (JPS). This study aims to evaluate the feasibility of a protocol for the robotic assessment of knee proprioception in individuals with patellar tendinopathy and to compare their proprioceptive performance with that of healthy controls. METHODS: Twenty-one participants with patellar tendinopathy (PTG) and fifteen healthy individuals (CG) (mean age: 32.36 (9.53) years) completed a single session of knee proprioception evaluation. JPS was assessed at 30° and 50° using passive (PJPS) and active (AJPS) repositioning tasks. FINDINGS: The PTG exhibited greater absolute angular error than the CG during PJPS at 30° (p = 0.04) and 50° (p = 0.04), and during AJPS at 30° (p = 0.01), with no differences detected in the 50° AJPS task (p > 0.05). The feasibility analysis showed that perceived effort, difficulty, and pain were generally low, whereas comfort and satisfaction were rated highly. INTERPRETATION: This study supports the use of a parallel robotic system as a viable instrument for assessing knee proprioception in people with patellar tendinopathy. Significant proprioceptive deficits were identified in this population compared to healthy controls, particularly in passive JPS at 30° and 50°, and in active JPS at 30°.