Morphology of the lumbar multifidus muscle in lumbar disc herniation at different durations and at different ages

Low Back Pain During and After Spaceflight: A Systematic Review with Meta-Analysis

Space flights can produce physiological changes in the spine, leading to the development of acute and chronic pain in passengers. However, there is a lack of comprehensive literature exploring physiological spine changes and acute and chronic pain in space passengers (astronauts and animals). The first aim of this study was to identify the physiological changes experienced by passengers (humans and animals) after space flight. The second aim was to identify the incidence of low back pain during and after space flight. This systematic review was conducted following PRISMA guidelines and was pre-registered in PROSPERO (ID 451144). We included Randomized Controlled Trials or longitudinal studies in humans and animals, and the variables must be assessed either in-flight or post-flight. We conducted a literature search in major databases combining the keywords: Pain; Space; Low Back Pain; Astronauts; Spine Changes; Microgravity; Physiological Changes; Humans; Animals. Risk of bias and quality of studies were analyzed, and the level of evidence was assessed using the GRADE system. After duplicates were removed, 115 abstracts were screened by two reviewers, and finally, 11 articles were included in this review. The evidence indicates that astronauts experience muscle atrophy in the lumbar multifidus with a moderate to large effect, especially in the L4-L5 and L5-S1 segments. Space flights also decrease the range of motion with a moderate effect, along with disc herniations and disc dehydration. 77% of astronauts experience pain during spaceflight, and 47% develop acute pain after spaceflight. Chronic pain was reported by 33% of the astronauts. After space flights, astronauts suffer from lumbar muscle atrophy, reduced range of motion, disc herniations, and disc dehydration, with a high incidence of both acute and chronic pain.

The Correlation between Unilateral Hip Bridge Endurance and Lumbar Multifidi Sonologic Characteristics in Physically Active Allied Healthcare Professionals at St. Luke's Medical Center - Quezon City: A Cross-sectional Study

Background and Objective

Low back pain is one of the most common work-related musculoskeletal disorders. Healthcare workers are prone to low back pain because of the nature of their profession. Low back pain may be related to lumbar multifidi atrophy or instability and poor core stability. Core stability can be assessed using the unilateral hip bridge endurance test. This cross-sectional study aims to determine the correlation between unilateral hip bridge endurance (UHBE) and sonologic characteristics of the bilateral L4-L5 lumbar multifidus muscles of physically active allied healthcare professionals.

Methods

Forty (40) physically active healthcare professionals (mean age = 31.3 ± 6.39 years, mean height = 161.17 ± 8.45 cm, mean weight = 61.88 ± 13.58 kg, mean BMI = 23.61 ± 3.68 kg/m2) were recruited via purposive sampling. The participants answered online versions of the Global Physical Activity Questionnaire (GPAQ) and Oswestry Disability Index. They subsequently underwent the UHBE test and ultrasound assessment of the L4-L5 multifidi. Multiplied anteroposterior (AP) and lateral linear (L) measurements were used to estimate L4-L5 multifidi size. The Pearson test was used to test for correlation between the primary outcomes of the study.

Results

There was no statistically significant correlation between Lumbar Multifidi CSA and UHBE Scores (r = -0.172, p > 0.05), and between Lumbar Multifidi CSA% Difference and UHBE Scores (r = -0.140, p > 0.05). However, results showed a very weak negative correlation between the Lumbar Multifidi CSA% Difference and UHBE Scores.

Conclusion

There is no definite evidence showing a correlation between core stability tests such as the unilateral hip bridge test scores and sonologic characteristics of the lumbar multifidi. However, lumbar multifidi symmetry may have a role with core stability. The correlation between core stability tests and lumbar multifidus morphology should be further investigated.

Magnetic Resonance Imaging Documentation of Approach Trauma With Lumbar Endoscopic Interlaminar, Translaminar, Compared to Open Microsurgical Discectomy

BACKGROUND

Endoscopic spine surgery is associated with less approach trauma than conventional open translaminar surgery. However, objective evidence to corroborate this empiric observation is scarce. Preservation of the anatomic attachment and sensory function of multifidus muscles have been stipulated to be critical to maintaining the normal function of the lumbar spinal motion segment. The authors were interested in comparing the postoperative approach trauma between traditional open translaminar microsurgical and interlaminar endoscopic discectomy.

METHODS

The approach trauma to the paraspinal muscles due to interlaminar or open microsurgical discectomy was evaluated on T2-weighted axial magnetic resonance imaging (MRI) images of 39 consecutive patients who underwent lumbar disc surgery. Postoperative MRI images taken at 4 days and within 1 year after surgery were analyzed. Eleven patients underwent conventional open translaminar microdiscectomy surgery. Endoscopic discectomy was performed on 17 patients via the interlaminar and on another 11 patients via the transforaminal approach. The immediate surgical approach trauma was estimated as the defect zone by measuring the normalized relative cross-sectional area (rCSA) of muscle disruption in the surgical corridor 4 days postoperatively. The long-term effect of surgical approach trauma was assessed by measuring the area of the paraspinal muscles that had been replaced by fatty tissue 1 year postoperatively.

RESULTS

The rCSA data showed diminished approach trauma with a smaller surgical defect zone in the interlaminar endoscopy group (17.6%) was smaller than in the microsurgical group 4 days postoperatively (41.2%). At 1 year postoperatively, the mean fatty replacement of the paraspinal muscles was 23.6% after microsurgery and 2.1% after the interlaminar endoscopy. Muscle recovery was substantially reduced in the interlaminar endoscopic group, with the muscle zone reducing from 20.3% to 2.1% when analyzed 1 year postoperatively. In the microsurgery group, the muscle damage by atrophy increased from 41.2% to 62.9% at 1 year postoperatively (P < 0.001). Fatty replacement of the multifidus muscle was seen on the ipsilateral and contralateral approach side. There was a negligible change in the muscle zone with the transforaminal approach.

CONCLUSIONS

Tissue trauma was significantly reduced with endoscopic surgery techniques compared with the traditional translaminar microdiscectomy approach. There was a minor postoperative tissue trauma and hardly any long-term replacement of the multifidus and paraspinal muscles by fatty tissue 1 year postoperatively with the endoscopic technique. The transforaminal approach has the least effect on the paraspinal muscles of the surgical motion segment. Further study is needed to investigate whether these findings translate into decreased postoperative instability or low back pain following endoscopic discectomy surgery.

CLINICAL RELEVANCE

MRI analysis of multifidus atrophy following various lumbar translaminar and transforaminal decompression techniques.

Does Unilateral Lumbosacral Radiculopathy Affect the Association between Lumbar Spinal Muscle Morphometry and Bone Mineral Density?

Age-related degenerative changes lead to a gradual decrease in bone mineral density (BMD) and muscle mass. We aimed to assess the effects of decreased BMD and lumbar denervation on lumbar spinal muscle morphometry and the relationship between BMD and lumbar spinal muscular morphometry, respectively. Eighty-one patients, aged 50–85 years, diagnosed with unilateral lumbosacral radiculopathy based on electrodiagnostic studies between January 2016 and April 2021 were enrolled. BMD T scores in the lumbar spine and hip were measured using dual-energy X-ray absorptiometry. The cross-sectional area (CSA) of the psoas, multifidus, and erector spinae located in the middle of the lumbar spine, between the L3 and L4 and between the L4 and L5 levels, respectively, was measured using axial MRI. Functional CSA (FCSA) was defined as the CSA of lean muscle mass. Pearson correlation analyses were performed to evaluate the association between BMD T scores and the CSA, FCSA, and the ratio of the FCSA to the CSA (functional ratio) for each side. The CSA of lumbar spinal muscles showed no significant correlation with lumbar BMD. The FCSA and functional ratio of lumbar spinal muscles were significantly correlated with lumbar BMD. There was no correlation between femur BMD and lumbar spinal muscle morphometry.

Is there a correlation between upper lumbar disc herniation and multifidus muscle degeneration? A retrospective study of MRI morphology

Background

The purpose of the study is to investigate the correlation between upper lumbar disc herniation (ULDH) and multifidus muscle degeneration via the comparison of width, the cross-sectional area and degree of fatty infiltration of the lumbar multifidus muscle.

Methods

Using the axial T2-weighted images of magnetic resonance imaging as an assessment tool, we retrospectively investigated 132 patients with ULDH and 132 healthy individuals. The total muscle cross-sectional area (TMCSA) and the pure muscle cross-sectional area (PMCSA) of the multifidus muscle at the L1/2, L2/3, and L3/4 intervertebral disc levels were measured respectively, and in the meantime, the average multifidus muscle width (AMMW) and degree of fatty infiltration of bilateral multifidus muscle were evaluated. The resulting data were analyzed to determine the presence/absence of statistical significance between the study and control groups. Multivariate logistical regression analyses were used to evaluate the correlation between ULDH and multifidus degeneration.

Results

The results of the analysis of the two groups showed that there were statistically significant differences (p < 0.05) between TMCSA, PMCSA, AMMW and degree of fatty infiltration. The multivariate logistic regression analysis indicated that the TMCSA, PMCSA, AMMW and the degree of fatty infiltration of multifidus muscle were correlated with ULDH, and the differences were statistically significant (P < 0.05).

Conclusions

A correlation could exist between multifidus muscles degeneration and ULDH, that may be a process of mutual influence and interaction. Lumbar muscle strengthening training could prevent and improve muscle atrophy and degeneration.

Effects of Volitional Spine Stabilization on Trunk Control During Asymmetric Lifting Task in Patients With Recurrent Low Back Pain

STUDY DESIGN

Prospective, concurrent-cohort study.

OBJECTIVES

To determine the effects of volitional preemptive abdominal contraction (VPAC) on trunk control during an asymmetric lift in patients with recurrent low back pain (rLBP) and compare with matched controls.

METHODS

Thirty-two rLBP patients and 37 healthy controls performed asymmetric lifting with and without VPAC. Trunk, pelvis, and hip biomechanical along with neuromuscular activity parameters were obtained using 3-dimensional motion capture and electromyography system. Hypotheses were tested using analysis of variance.

RESULTS

The VPAC resulted in significantly reduced muscle activity across all trunk extensor muscles in both groups (M ± SD, 6.4% ± 8.2% of maximum contraction; P ≤ .005), and reduced trunk side flexion (1.4° ± 5.1° smaller; P ≤ .005) and hip abduction (8.1° ± 21.1° smaller; P ≤ .003). rLBP patients exhibited reduced muscle activity in external oblique (12.3% ± 5.5% of maximum contraction; P ≤ .012), as well as decreased hip flexion (4.7°, P ≤ .008) and hip abduction (5.2°, P ≤ .001) at the final position of lifting in comparison with healthy controls.

CONCLUSIONS

The results of this study defend the recommendation that the use of a VPAC increase spine stability during an asymmetrical loading task. Our results provide an indication that a VPAC strategy that is achieved during an asymmetric lifting decreases exposure for lumbar spine injury and instability. Spine care providers and ergonomists can use this information when designing neuromuscular control training programs, both for healthy individuals aimed at prevention of injury, as well as those with a history of rLBP, aimed at full functional recovery and protection from future injury.

Muscle Hypertrophy and Architectural Changes in Response to Eight-Week Neuromuscular Electrical Stimulation Training in Healthy Older People

Loss of muscle mass of the lower limbs and of the spine extensors markedly impairs locomotor ability and spine stability in old age. In this study, we investigated whether 8 w of neuromuscular electrical stimulation (NMES) improves size and architecture of the lumbar multifidus (LM) and vastus lateralis (VL) along with locomotor ability in healthy older individuals. Eight volunteers (aged 65 ≥ years) performed NMES 3 times/week. Eight sex- and age-matched individuals served as controls. Functional tests (Timed Up and Go test (TUG) and Five Times Sit-to-Stand Test (FTSST)), VL muscle architecture (muscle thickness (MT), pennation angle (PA), and fiber length (FL)), along with VL cross-sectional area (CSA) and both sides of LM were measured before and after by ultrasound. By the end of the training period, MT and CSA of VL increased by 8.6% and 11.4%, respectively. No significant increases were observed in FL and PA. LM CSA increased by 5.6% (left) and 7.1% (right). Interestingly, all VL architectural parameters significantly decreased in the control group. The combined NMES had a large significant effect on TUG (r = 0.50, p = 0.046). These results extend previous findings on the hypertrophic effects of NMES training, suggesting to be a useful mean for combating age-related sarcopenia.

Inconsistent descriptions of lumbar multifidus morphology: A scoping review

BACKGROUND

Lumbar multifidus (LM) is regarded as the major stabilizing muscle of the spine. The effects of exercise therapy in low back pain (LBP) are attributed to this muscle. A current literature review is warranted, however, given the complexity of LM morphology and the inconsistency of anatomical descriptions in the literature.

METHODS

Scoping review of studies on LM morphology including major anatomy atlases. All relevant studies were searched in PubMed (Medline) and EMBASE until June 2019. Anatomy atlases were retrieved from multiple university libraries and online. All studies and atlases were screened for the following LM parameters: location, imaging methods, spine levels, muscle trajectory, muscle thickness, cross-sectional area, and diameter. The quality of the studies and atlases was also assessed using a five-item evaluation system.

RESULTS

In all, 303 studies and 19 anatomy atlases were included in this review. In most studies, LM morphology was determined by MRI, ultrasound imaging, or drawings - particularly for levels L4-S1. In 153 studies, LM is described as a superficial muscle only, in 72 studies as a deep muscle only, and in 35 studies as both superficial and deep. Anatomy atlases predominantly depict LM as a deep muscle covered by the erector spinae and thoracolumbar fascia. About 42% of the studies had high quality scores, with 39% having moderate scores and 19% having low scores. The quality of figures in anatomy atlases was ranked as high in one atlas, moderate in 15 atlases, and low in 3 atlases.

DISCUSSION

Anatomical studies of LM exhibit inconsistent findings, describing its location as superficial (50%), deep (25%), or both (12%). This is in sharp contrast to anatomy atlases, which depict LM predominantly as deep muscle. Within the limitations of the self-developed quality-assessment tool, high-quality scores were identified in a majority of studies (42%), but in only one anatomy atlas.

CONCLUSIONS

We identified a lack of standardization in the depiction and description of LM morphology. This could affect the precise understanding of its role in background and therapy in LBP patients. Standardization of research methodology on LM morphology is recommended. Anatomy atlases should be updated on LM morphology.