Lumbar axial rotation kinematics in men with non-specific chronic low back pain

Background: Lumbar flexion, coupled with rotation, is a dominant factor in the etiology and exacerbation of low back pain. Yet, no study has examined its kinematics in patients with non-specific chronic low back pain (NSCLBP). The aim of the study was to evaluate the lumbar rotation kinematics in neutral standing and with full flexion in men with NSCLBP. Methods: ROM, average velocity, maximum velocity and maximal acceleration of lumbar rotation in neutral standing and with full flexion were measured using an industrial lumbar motion monitor in 50 men (25 with NSCLBP and 25 controls). VAS and Rolland Morris questionnaire were also included. Findings: All examined kinematical parameters were significantly lower in men with NSCLBP compared with controls (↓ROM = 29%–45%; ↓AV = 40%–68%; ↓MV = 25%–50%; ↓MA = 20%–37%). Left rotation manifested smaller kinematic values (except for MA) than right rotation (Δ ROM = 35%; Δ AV = 66%; Δ MV = 19%) in NSCLBP. Most kinematical parameters significantly decreased from neutral standing to standing with flexion (right rotation: ↓ROM = 43%–45%, ↓AV = 38%–45%, ↓MV = 24%–27%, ↓MA for the NSCLBP group = 21%; left rotation: ↓ROM = 25%–38%, ↓AV in the control group: =34%, ↓MV in the control group: =23%, ↓MA in the control group = 25%). No correlations were found between all measured kinematical parameters, VAS and RMQ total score in the NSCLBP group. Interpretation: The kinematic parameters of lumbar rotation were reduced in men with NSCLBP compared with controls both in neutral standing and with fully forward bending. Most lumbar rotation kinematics decreased from neutral standing to standing with flexion.