Analysis of Biomechanical Properties of the Lumbar Extensor Myofascia in Elderly Patients with Chronic Low Back Pain and That in Healthy People

Abstract

There is limited research on the changes of biomechanical characteristics of the lumbar extensor myofascia in elderly patients with chronic low back pain. This study aimed to compare the biomechanical properties of the lumbar extensor myofascia in elderly patients with chronic low back pain and healthy people when resting and to analyze the relationship between the Japanese Orthopedic Association (JOA) score, visual analog scale (VAS) score, Cobb angle, and disease course and the biomechanical characteristics of the lumbar extensor myofascia. This case-control study included 40 elderly patients with chronic low back pain and 40 healthy volunteers. MyotonPRO was used to measure the biomechanical properties of the bilateral lumbar extensor myofascia (at L3/L4 level) in all participants, and the reliability of the MyotonPRO test was measured. Cobb angle was measured from lumbar computed tomography or magnetic resonance imaging data. JOA and VAS scores were used to evaluate lumbar function and pain. We found that muscle tone, stiffness, and elasticity of the left and right lumbar extensor myofascia in patients with chronic low back pain were very reliable among different operators. The average lumbar extensor muscle tone and stiffness were significantly higher in patients with chronic low back pain than those in healthy controls. The average elasticity of the lumbar extensor myofascia of patients with chronic low back pain was significantly lower than that of the healthy controls. The JOA score was negatively correlated, while the VAS score was positively correlated with the mean values of tone, stiffness, and elasticity of the bilateral lumbar extensor myofascia (logarithmic decrement). Disease course had no significant correlation with muscle tone, stiffness, and elasticity of the lumbar extensor myofascia. No significant correlation was found between Cobb angle and muscle tone, stiffness, and elasticity of the lumbar extensor myofascia in either group.

Paravertebral Muscle Mechanical Properties and Spinal Range of Motion in Patients with Acute Neck or Low Back Pain: A Case-Control Study

“…Therefore, cervical decrement, that is inverse to the elasticity, seems to be the main mechanical property that discriminates groups. Recently, it has been reported that elasticity is lower in elderly patients with chronic LBP [ 44 ] and in patients with ankylosing spondylitis [ 45 ], although always when assessed in lumbar region, which is consistent with the current results.…”

“…The mean values of lumbar musculature stiffness of young control subjects [ 28 ] and elder control subjects [ 44 ] were similar to those values obtained in the current study for all groups. Furthermore, current values of tone and stiffness were lower than those reported for other pathological populations, such as young [ 28 , 71 ] and elderly [ 44 ] individuals with chronic spinal pain, and even inflammatory pain [ 29 ]. In fact, the differences among the three groups, which did not show statistical significance, were lower than the minimum detectable change established for these variables in the lumbar muscles [ 29 ], and may be explained by the acute state of patients in our study, and the rest assessment position.…”

“…This response is measured by an accelerometer [ 43 ]. The MMPs recorded in this study included: frequency , measured in Hz, representing the muscle tone at rest (the higher frequency, the higher muscle tone); stiffness , measured in N/m, reflecting the capacity of the muscle to resist contraction or external pressure to deform (the greater stiffness, the greater muscle toughness); logarithmic decrement of oscillation amplitude, that has no unit, and is a measure of muscle elasticity (the higher decrement, the lower elasticity [ 44 ]); creep , that has also no unit, the material property in which progressive deformation occurs with time while a constant stress is applied; and, relaxation , measured in ms., describing the phenomenon of stress decrease with time, while the applied strain is constant, being the stress relaxation time the recovery time for the material to return to its normal state after deformation [ 45 ].…”

“…The probe was first loaded by pushing against the skin surface to the required depth (indicated by a change in light from red to green), and the device applied impulses to induce damped oscillations within the muscle belly. During the test, the coefficient of variation (CV) of each test result was observed, and if the CV was more than 3%, the test was repeated again [ 44 ]. Lumbar measurements were carried out by placing the probe of the device perpendicular to the muscular belly of the erector spinal column, 2.5 cm from the midline of the spinous process of L5 [ 46 ] ( Figure 1 a).…”

A Comparison of Clinical Spinal Mobility Measures to Experimentally Derived Lumbar Spine Passive Stiffness

“…38,39 A myotonometer measures the resistance of a tissue to an impulse force applied to the overlying skin and quantifies stiffness based on the damped natural oscillation response of the tissue. 40,41 This technique is reliable in measuring stiffness of the lumbar erector spinae in back-healthy controls 38 and has identified greater lumbar erector spinae stiffness in females with LBP compared with controls 41 and older patients with LBP, 42 as well as greater lumbar myofascial stiffness in patients with ankylosing spondylitis compared with age-comparable controls. 43 Myotonometry is unable to determine joint stiffness; however, when used in conjunction with the previously described passive jig, it may provide powerful insight into how tissues of the low back contribute to the lumped mechanical stiffness measure.…”