Knee joint repositioning error in different trunk positions among females with chronic nonspecific low back pain: A cross-sectional study

Purpose: Proprioception is a self-perceived sense of position and movement of one's body and its deficits can lead to motor control problems such as delayed muscle reflexes. Previous studies have confirmed lumbar proprioception impairments among individuals with Low Back Pain (LBP), which can afflict the normal central sensorymotor control and hence increases the risk of abnormal loading on the lumbar spine. Although the local investigation of proprioception is important, its influence on other joints in a kinetic chain particularly between extremities and spine should not be ignored. Therefore, the aim of this study was to compare the proprioception of knee joint in different trunk positions among females with chronic nonspecific low back pain (CNSLBP) and healthy females. Design: The study included 24 healthy subjects and 25 patients with CNSLBP participated in this study. Repositioning error of knee joint in four different lumbar positions including flexion, neutral position, 50% ROM of left rotation and 50% ROM right rotation was evaluated using an inclinometer. Absolute error and constant error were obtained and analyzed. Results: Absolute error in flexion and neutral positions in the individuals with CNSLBP were significantly higher than in healthy individuals; whereas, there was no significant difference in absolute and constant error between the two groups in 50% rotation to either side. Conclusion: This study showed that knee joint repositioning accuracy was reduced in patients with CNSLBP compared to healthy ones.