Discriminant analysis of neuromuscular variables in chronic low back pain
Denise Martineli Rossi1, Mary Hellen Morcelli1, Adalgiso Coscrato Cardozo2
1Department of Physical Therapy and Occupational Therapy, São Paulo State University, Marília, Brazil.
Background:
Investigation and discrimination of neuromuscular variables related to the complex aetiology of low back pain could contribute to clarifying the factors associated with symptoms.
Objective:
Analysing the discriminative power of neuromuscular variables in low back pain.
Methods:
This study compared muscle endurance, proprioception and isometric trunk assessments between women with low back pain (LBP, n=14) and a control group (CG, n=14). Multivariate analysis of variance and discriminant analysis of the data were performed.
Results:
The muscle endurance time (s) was shorter in the LBP group than in the CG (p=0.004) with values of 85.81 (37.79) and 134.25 (43.88), respectively. The peak torque (Nm/kg) for trunk extension was 2.48 (0.69) in the LBP group and 3.56 (0.88) in the GG (p=0.001); for trunk flexion, the mean torque was 1.49 (0.40) in the LBP group and 1.85 (0.39) in the CG (p=0.023). The repositioning error (degrees) before the endurance test was 2.66 (1.36) in the LBP group and 2.41 (1.46) in the CG (p=0.664), and after the endurance test, it was 2.95 (1.94) in the LBP group and 2.00 (1.16) in the CG (p=0.06). Furthermore, the variables showed discrimination between the groups (p=0.007), with 78.6% of the individuals with low back pain correctly classified in the LBP group. In turn, variables related to muscle activation showed no difference in discrimination between the groups (p=0.369).
Conclusion:
Based on these findings, the clinical management of low back pain should consist of both resistance and strength training, particularly in the extensor muscles.
