Efficacy of Bioelectrical Impedance Analysis for the Evaluation of Physical Impairment in Chronic Low Back Pain. Results from a Cohort Study

Introduction: Determining the effect of body composition on chronic low back pain seems to have the potential to improve our understanding of its mechanism and to develop novel preventive and therapeutic approaches.  Aim: The purpose of the present study was to assess by electrical impedance the composition of lower extremities of individuals with chronic low back pain. Materials and methods: One hundred and twenty-one adult participants with diagnosed chronic low back pain were recruited in this study. The study activities were divided into three phases: phase 1 – self-administered questionnaires, phase 2 – biomedical examination (including anthropometric measurements and physical function performance tests), and phase 3 – bioimpedance analysis. Results: Our results showed that chronic low back pain differentiates the circumference of thigh and calf of the symptomatic leg. Besides, patients experience pain also in hip, thigh, and calf, which act as a barrier to patient’s personal, professional, social, and recreational activities. Furthermore, patients appear with ‘unstable’ walking, reduced balance, and reduced general physical condition that affect all of the neuromuscular structures of the locomotor system. Interestingly, patients seem to be characterized by a tendency to deposit fat and to decrease muscle mass in the symptomatic limb regardless of the gender. Conclusions: In the present study, we determine the profile of a patient with chronic low back pain through a variety of measurements. Chronic low back pain causes several structural changes to the symptomatic leg of the patients leading to ‘unstable’ walking, reduced balance, and reduced general physical condition. It is clear that further studies using bioimpedance analysis are needed to address the concerns raised by investigating a multifactorial condition such as chronic low back pain.