Correlation of Chronic Low-Back Pain Behavior and Muscle Function Examination of the Flexion–Relaxation Response

The Biomechanical and Clinical Significance of the Lumbar Erector Spinae Flexion-Relaxation Phenomenon: A Review of Literature

“…40 In this work, Ahern et al 41 noted that pain behavior, more specifically, guarded movements, was significantly correlated to the FRP. Adding to this line of investigation of assessing the FRP, Mannion et al 5 investigated 148 patients with CLBP and found that 55% showed no relaxation of the erector spinae muscles at L5 in the fully flexed position.…”

The relationship between pelvis–trunk coordination and low back pain in individuals with transfemoral amputations

“…However, the lower frontal plane CRP values in the TFA groups indicate rigidity between the pelvis and trunk during walking by protective ''guarding'' or splinting of the segments [14,26,27] or a compensatory mechanism to enhance stability. While walking on level ground individuals with TFA may increase rigidity along some planes to allow attention to be diverted to stabilizing the center of mass, hiking the hip to lift the residual limb and prosthesis, and clearing the toe during swing.…”

Lumbar magnetic resonance imaging hypolordosis in symptomatic patients: association with paraspinal muscle spasms

“…A study of the behavior and muscle function of patients with low back pain showed that this muscle guarding (ie, absence of flexion-relaxation response) should receive more attention by clinicians as part of routine physical examinations because this muscle dysfunction can restrict range of motion and possibly lead to the development of maladaptive postures and movements secondary to persistent pain. 25 In fact, kyphotic angulation and straightening or reversal of cervical lordosis are commonly seen after trauma. Although these may indeed be normal variants, muscle spasms are widely used to explain these variations between patients with pain.…”