Lumbar Multifidus and Erector Spinae Muscle Synergies in Patients with Nonspecific Low Back Pain During Prone Hip Extension: A Cross‐sectional Study

Abstract

Background Prone hip extension is used to clinically assess movement control in patients with nonspecific low back pain (LBP). Excessive lumbopelvic movements and altered muscle activation patterns are common in patients with nonspecific LBP. However, no evidence exists regarding lumbar multifidus and lumbar erector spinae muscle synergy patterns in patients with nonspecific LBP during this clinical test. Objective To determine the difference in lumbopelvic motion and change in muscle synergy between patients with nonspecific LBP and healthy individuals. Design A cross‐sectional study design. Setting University physical therapy clinic and laboratory. Participants Seven patients with nonspecific LBP (age [mean ± SD] 29 ± 5 years, 43% female, body mass index [BMI] of 25 ± 2 kg/m2, Numeric Pain Rating Scale 6 ± 2; Oswestry Disability Index 20% ± 8%) and seven age‐, sex‐, and BMI‐matched healthy individuals (mean age 28 ± 5 years, 43% female, BMI of 22 ± 2 kg/m2) were recruited. Methods Each participant performed six repetitions of prone hip extension on each side; kinematic and electromyographic data were collected simultaneously. Main Outcome Measurements Kinematic data were used to represent lumbopelvic motion, whereas electromyography (EMG) data were used to represent muscle activity. A paired t‐test was used to determine the difference in lumbopelvic motion. Principal component analysis and two‐way repeated‐measures analysis of variance were used to extract muscle synergies and identify differences in muscle synergy patterns between and within groups. Results Results demonstrated no significant group difference (P > .05) in amount of lumbopelvic motion. However, healthy individuals synergistically activate lumbar multifidus and lumbar erector spinae with 81.0% variance accounted for (VAF). Patients with nonspecific LBP had an altered synergy with independent activation of lumbar multifidus on the painful side with 32.0% VAF and the lumbar multifidus on the nonpainful side, and both lumbar erector spinae with 52.2% VAF synergistically activated. Conclusions These findings suggest that clinicians should focus on muscle activation patterns rather than the amount of lumbopelvic motion during clinical observation of prone hip extension. Level of Evidence Level III.

Effectiveness of Combined Stretching and Strengthening Exercise Using Rehabilitation Exercise System with a Linear Actuator and MR Damper on Static and Dynamic Sitting Postural Balance: A Feasibility Study

“…Previous research reported that improper muscle activation pattern of the erector spinae and multifidus muscles during anterior and posterior pelvic tilting may be associated with sagittal misalignment. Because these muscles are involved in controlling the movement in the sagittal plane [36]. Similar to the results in LPT, the asymmetrical muscle activities were also displayed in patients with spinal deformity when conducting the lateral bending motions [34].…”

Lumbar muscles biomechanical characteristics in young people with chronic spinal pain

“…The study conducted by Lothe et al, [43] reported no significant difference in muscle activity between people with low back pain when compared to pain free participants. Other study provided evidence to support that people with low back pain have different muscle activation pattern among the synergy muscles groups [44]. It is therefore unlikely that muscle properties might not be associated with pain level at rest but more related to pain elicited during movement.…”

Differences in Lumbar Multifidus Activity and its Association with Lumbar Range of Motion among patients With Unilateral Chronic Low Back Pain

“…16,17 The results of previous studies with the comparison of symptomatic and symptomatic individuals with CLBP and with the comparison of painful and nonpainful sides are the same as current study elaborating the higher muscle contraction in CLBP than control. 17,18 However, contrary to this another study found no significant difference between non-painful and painful individuals with CLBP 19 . These differences in results may be due to differences in movement during the measurement of %MVC.…”

“…Studies have concluded that clinicians should focus on muscle activation patterns in clinical observation of a lumbar range of motion 5,18 . In the current study, the increase in %MVC of painful side LM correlated with the decrease in lumbar flexion.…”