Ipsilateral Erector Spinae Muscle Research Articles

Motor recruitment pattern during the prone hip extension test: is hip extension initiated by the hip or the lumbar extensor muscles?

Background/Aims Prone hip extension motion pattern derives from the motor muscle firing pattern, and functional deficits are determined by comparing this pattern with a normal prone hip extension motion muscle recruitment pattern, defined more than 30 years ago by scientifically insufficient methods. The aim of this study was to examine the differences between electromyography recruitment onsets and orders of muscles participating in prone hip extension motion, and to determine whether there is a consistent and dominant motor pattern. Methods The sample consisted of 106 healthy participants. Onset times of semitendinosus, ipsilateral and contralateral erector spinae muscles were determined as 10% of the peak rectified amplitude of the electromyography signal for each of the 18 prone hip extension bilateral repetitions. These values were used to determine the recruitment order for each repetition, as well as to calculate the average ipsilateral and contralatral normalised onset times (ie relative times to firing of the semitendinosus muscle). The main analysis was performed using a one-way analysis of variance. The level of statistical significance was set at P<0.05. Results One-way analysis of variance revealed a significantly delayed onset of prone hip extension of the contralateral erector spinae muscles compared to the other muscles (F=7.02; P<0.001; Cohen's f=0.209). Muscle activation initiated by the semitendinosus and ipsilateral erector spinae muscles was the most common. Conclusions The ipsilateral erector spinae muscle contracts simultaneously with the semitendinosus muscle as a proximal stabiliser, enabling distal hip mobility. The use of the prone hip extension test in recognising dysfunction is limited to when the contralateral erector spinae muscle is initiated first during prone hip extension.

Effect of the Abdominal Hollowing and Bracing Maneuvers on Activity Pattern of the Lumbopelvic Muscles During Prone Hip Extension in Subjects With or Without Chronic Low Back Pain: A Preliminary Study

ObjectiveThe purpose of this study was to compare the effect of abdominal hollowing (AH) and abdominal bracing (AB) maneuvers on the activity pattern of lumbopelvic muscles during prone hip extension (PHE) in participants with or without nonspecific chronic low back pain (CLBP). MethodsTwenty women with or without CLBP participated in this cross-sectional observational study. The electromyographic activity (amplitude and onset time) of the contralateral erector spinae (CES), ipsilateral erector spinae (IES), gluteus maximus, and biceps femoris muscles was measured during PHE with and without abdominal maneuvers. A 3-way mixed model analysis of variance and post hoc tests were used for statistical analysis. ResultsBetween-group comparisons showed that the CES onset delay during PHE alone was greater (P = .03) and the activity level of IES, CES, and biceps femoris in all maneuvers (P < .05) was higher in patients with CLBP than in asymptomatic participants. In asymptomatic participants, PHE + AH significantly decreased the signal amplitude (AMP) of IES (P = .01) and CES (P = .02) muscles. In participants with CLBP, IES muscle AMP was lower during PHE + AH compared with PHE + AB and PHE alone. With regard to onset delay, the results also showed no significant difference between maneuvers within either of the 2 groups (P > .05). ConclusionsPerformance of the AH maneuver decreased the erector spinae muscle AMP in both groups, and neither maneuver altered the onset delay of any of the muscles in either group. The low back pain group showed higher levels of activity in all muscles (not statistically significant in gluteus maximus during all maneuvers). The groups were similar according to the onset delay of any of the muscles during either maneuver.

Bilateral experimental neck pain reorganize axioscapular muscle coordination and pain sensitivity.

Neck pain is a large clinical problem where reorganized trunk and axioscapular muscle activities have been hypothesised contributing to pain persistence and pain hypersensitivity. This study investigated the effects of bilateral experimental neck pain on trunk and axioscapular muscle function and pain sensitivity. In 25 healthy volunteers, bilateral experimental neck pain was induced in the splenius capitis muscles by hypertonic saline injections. Isotonic saline was used as control. In sitting, subjects performed slow, fast and slow-resisted unilateral arm movements before, during and after injections. Electromyography (EMG) was recorded from eight shoulder and trunk muscles bilaterally. Pressure pain thresholds (PPTs) were assessed bilaterally at the neck, head and arm. Data were normalized to the before-measures. Compared with control and post measurements, experimental neck pain caused (1) decreased EMG activity of the ipsilateral upper trapezius muscles during all but slow-resisted down movements (p<0.001), and (2) increased EMG activity in the ipsilateral erector spinae muscle during slow and fast movements (p<0.02), and in the contralateral erector spinae muscle during all but fast up and slow-resisted down movements (p<0.007). The PPTs in the painful condition increased at the head and arm compared with post measurements and the control condition (p<0.001). In the post-pain condition, the neck PPT was decreased compared with the control condition (p<0.001). Acute bilateral neck pain reorganized axioscapular and trunk muscle activity together with local hyperalgesia and widespread hypoalgesia indicating that acute neck pain immediately affects trunk and axioscapular function which may affect both assessment and treatment. Bilateral clinical neck pain alters axioscapular muscle coordination but only effects of unilateral experimental neck pain has been investigated. Bilateral experimental neck pain causes task-dependent reorganized axioscapular and trunk muscle activity in addition to widespread decrease in pressure pain sensitivity.

Asymmetrical trunk muscle activities and kinematics during dominant and nondominant leg lifts in subjects with lumbar rotation with flexion syndrome

BACKGROUND: Patients with lower back pain due to lumbar rotation with flexion syndrome (LRFS) have greater asymmetry of rotation in the lumbopelvic region than healthy people. OBJECTIVE: To understand the activities of the trunk muscle and kinematics of the trunk and pelvis in patients with LRFS during the bird-dog (BD) exercise with dominant non-dominant leg lifts, a frequently prescribed stabilization exercise. METHODS: We compared activity and kinematics during the BD exercise with dominant and non-dominant leg lifts in 11 patients (6 male, 5 female) with LRFS who were recruited from a university. RESULTS: Significantly lower activation of the ipsilateral erector spinae muscle was found during the nondominant leg lift than the dominant leg lift in patients performing the BD exercise (t = −3.71, p = 0.04). In addition, the trunk was significantly flexed during the dominant leg lift (t = −6.069, p = 0.00) and bent to the right side (t = 3.131, p = 0.01) during both dominant and nondominant leg lifts. CONCLUSIONS: These results imply the presence of asymmetrical muscle activity and kinematics in the trunks of subjects with LRFS. This information should be considered for prescribing exercises to such subjects.