Three-Dimensional Functional Capacity of Normals and Low Back Pain Patients

Abstract

Most current functional capacity evaluations focus on sagittal range of motion, strength testing as well as simulation of daily activities and job tasks as measures of wellness. The goal of this study was to evaluate the dynamic functional motion capacity of normals and low back pain patients in the three cardinal planes of the body. The hypothesis was that injury would not only affect sagittal motion but also lateral and twisting motions that would load the spine in a different manner. Trunk motion parameters of range of motion (ROM), velocity and acceleration were measured in all three planes of the body as subjects performed three separate experimental tasks, eliciting motion in each plane of the body. The MANOVA results showed a significant difference between the patients and normals. The final discriminant function model predicting membership for the two groups contained ROM, velocity, and acceleration parameters with two measures from each experimental task. The cross-validation error rate for the model was 4%. These results provide insight into new methods for functional capacity evaluation of low back pain patients which may influence return to work decisions.