Influence of the Generation of Motor Mental Images on Physiotherapy Treatment in Patients with Chronic Low Back Pain.

BACKGROUND: Patients with nonspecific chronic low back pain (NCLBP) have greater difficulty generating kinesthetic and visual motor imagery. OBJECTIVES: The main aim of this study was to determine whether the ability to generate mental motor imagery (MIab) influences psychological, motor, and disability variables in patients with NCLBP. The secondary aim was to determine whether an approach based on therapeutic exercise (TE) and therapeutic education (TEd) could improve the MIab in those patients with less ability to perform it. STUDY DESIGN: Cross-sectional and quasiexperimental study. SETTING: Physical Therapy Unit of primary health care center in Madrid, Spain. METHODS: A total of 68 patients were divided into 2 groups according to a greater (n = 34) or lesser (n = 34) MIab. Treatment was based on TEd and TE for the group with less ability to generate kinesthetic and visual motor imagery. The outcome measures were imagery requested time, self-efficacy, disability, pain intensity, lumbar strength, psychological variables, and MIab. RESULTS: The group with lesser MIab showed lower levels of self-efficacy (P = 0.04; d, -0.47) and lower levels of lumbar strength and extension strength (P = 0.04; d, -0.46 and P = 0.02; d, -0.52, respectively). After the intervention with TE and TEd, MIab (both kinesthetic and visual) improved significantly, with a moderate to large effect size (P <= 0.01; d, -0.80 and P <= 0.01; d, -0.76, respectively), as did pain intensity, lumbar strength, disability, and psychological variables (P < 0.05), but not levels of self-efficacy (P > 0.05). Based on the results, the patients with NCLBP with lesser MIab achieved lower levels of self-efficacy and lower strength levels. LIMITATIONS: The results of this study should be interpreted with caution because of its quasiexperimental design and a bias selection. CONCLUSIONS: A clinical TE approach, coupled with a TEd program, resulted in significant improvement in MIab (both kinesthetic and visual), reduced pain intensity, increased lumbar strength, reduced disability, and improved psychological variables, but it did not significantly improve self-efficacy levels in the patients with NCLBP. KEY WORDS: Chronic low back pain, motor imagery, disability, lumbar strength.