Ultrasound Evaluation of the Combined Effects of Thoracolumbar Fascia Injury and Movement Restriction in a Porcine Model

Ultrasound Imaging of Thoracolumbar Fascia: A Systematic Review

Over the past decade, there has been a notable increase in research focused on ultrasound imaging of thoracolumbar fascia (TLF). Nevertheless, published papers' results about the application of US imaging in TLF examination are still sparse. Background and Objevtives: Hence, this systematic review was performed aiming to firstly investigate the use and the methodology of ultrasound imaging to assess pathologic and healthy TLF. Secondarily, we aim to assess intra- and inter-observer reproducibility of US imaging in TLF assessment. Materials and Methods: The search was done on PubMed and Web of Science database from inception to April 2024. Furthermore, the references of included papers were thoroughly checked to find eligible publications. The MeSH keywords used were: "Thoracolumbar fascia", "Ultrasound Imaging", "Ultrasound", "Ultrasonography", and "Ultrasound examination". Results: Studies were aimed primarily at TLF diagnosis, treatment monitoring, or evaluating movement-related changes, underscoring the diverse clinical applications. The US parameters assessed included TLF thickness, echogenicity, stiffness, deformation, shear strain, and displacement, providing comprehensive insights into TLF features. Conclusions: Advanced US imaging holds promise as a reliable tool in musculoskeletal assessment, offering insights into TLF pathology/disfunction, treatment outcomes, and movement dynamics.

Injecting hyaluronan in the thoracolumbar fascia: A model study

Hyaluronan (HA) has been recently identified as a key component of the densification of thoracolumbar fascia (TLF), a potential contributor to non-specific lower back pain (LBP) currently treated with manual therapy and systemic or local delivery of anti-inflammatory drugs. The aim of this study was to establish a novel animal model suitable for studying ultrasound-guided intrafascial injection prepared from HA with low and high Mw. Effects of these preparations on the profibrotic switch and mechanical properties of TLF were measured by qPCR and rheology, respectively, while their lubricating properties were evaluated by tribology. Rabbit proved to be a suitable model of TLF physiology due to its manageable size enabling both TLF extraction and in situ intrafascial injection. Surprisingly, the tribology showed that low Mw HA was a better lubricant than the high Mw HA. It was also better suited for intrafascial injection due to its lower injection force and ability to freely spread between TLF layers. No profibrotic effects of either HA preparation in the TLF were observed. The intrafascial application of HA with lower MW into the TLF appears to be a promising way how to increase the gliding of the fascial layers and target the myofascial LBP.

The relationship between clinical examination measures and ultrasound measures of fascia thickness surrounding trunk muscles or lumbar multifidus fatty infiltrations: An exploratory study

Patients with chronic low back pain (CLBP) exhibit remodelling of the lumbar soft tissues such as muscle fatty infiltrations (MFI) and fibrosis of the lumbar multifidus (LuM) muscles, thickness changes of the thoracolumbar fascia (TLF) and perimuscular connective tissues (PMCT) surrounding the abdominal lateral wall muscles. Rehabilitative ultrasound imaging (RUSI) parameters such as thickness and echogenicity are sensitive to this remodelling. This experimental laboratory study aimed to explore whether these RUSI parameters (LuM echogenicity and fascia thicknesses), hereafter called dependent variables (DV) were linked to independent variables (IV) such as (1) other RUSI parameters (trunk muscle thickness and activation) and (2) physical and psychological measures. RUSI measures, as well as a clinical examination comprising physical tests and psychological questionnaires, were collected from 70 participants with LBP. The following RUSI dependent variables (RUSI-DV), measures of passive tissues were performed bilaterally: (1) LuM echogenicity (MFI/fibrosis) at three vertebral levels (L3/L4, L4/L5 and L5/S1); (2) TLF posterior layer thickness, and (3) PMCT thickness of the fasciae between subcutaneous tissue thickness (STT) and external oblique (PMCT_STT/EO ), between external and internal oblique (PMCT_EO/IO ), between IO and transversus abdominis (PMCT_IO/TrA ) and between TrA and intra-abdominal content (PMCT_TrA/IA ). RUSI measures of trunk muscle's function (thickness and activation), also called measures of active muscle tissues, were considered as independent variables (RUSI-IV), along with physical tests related to lumbar stability (n = 6), motor control deficits (n = 7), trunk muscle endurance (n = 4), physical performance (n = 4), lumbar posture (n = 2), and range of motion (ROM) tests (n = 6). Psychosocial measures included pain catastrophizing, fear-avoidance beliefs, psychological distress, illness perceptions and concepts related to adherence to a home-based exercise programme (physical activity level, self-efficacy, social support, outcome expectations). Six multivariate regression models (forward stepwise selection) were generated, using RUSI-DV measures as dependent variables and RUSI-IV/physical/psychosocial measures as independent variables (predictors). The six multivariate models included three to five predictors, explaining 63% of total LuM echogenicity variance, between 41% and 46% of trunk superficial fasciae variance (TLF, PMCT_STT/EO ) and between 28% and 37% of deeper abdominal wall fasciae variance (PMCT_EO/IO , PMCT_IO/TrA and PMCT_TrA/IA ). These variables were from RUSI-IV (LuM thickness at rest, activation of IO and TrA), body composition (percent fat) and clinical physical examination (lumbar and pelvis flexion ROM, aberrant movements, passive and active straight-leg raise, loaded-reach test) from the biological domain, as well as from the lifestyle (physical activity level during sports), psychological (psychological distress-cognitive subscale, fear-avoidance beliefs during physical activities, self-efficacy to exercise) and social (family support to exercise) domains. Biological, psychological, social and lifestyle factors each accounted for substantial variance in RUSI-passive parameters. These findings are in keeping with a conceptual link between tissue remodelling and factors such as local and systemic inflammation. Possible explanations are discussed, in keeping with the hypothesis-generating nature of this study (exploratory). However, to impact clinical practice, further research is needed to determine if the most plausible predictors of trunk fasciae thickness and LuM fatty infiltrations have an effect on these parameters.

Effects of a Myofascial Technique on the Stiffness and Thickness of the Thoracolumbar Fascia and Lumbar Erector Spinae Muscles in Adults with Chronic Low Back Pain: A Randomized before-and-after Experimental Study

The thoracolumbar fascia (TLF) may be a pain generator, given its rich innervation. Structural and biomechanical changes have also been documented in adults with chronic non-specific low back pain (LBP). Myofascial techniques (MFTs) are commonly used in manual therapy and are hypothesized to reduce tissue stiffness and pain. However, evidence for these effects is limited. The objective of this study was to evaluate the immediate effects of a standardized MFT compared to a simulated MFT on: (1) the stiffness of the TLF and erector spinae muscles (shear-wave sonoelastography), (2) the thickness of the TLF (B-mode ultrasound), and (3) pain intensity (numerical rating scale). Forty-nine participants with chronic non-specific LBP were included in a randomized before-and-after experimental study. Outcome measures were collected before (T0) and immediately after the intervention (T1). Pain intensity was also assessed on day two (T2) and seven (T7). The MFT group showed a significant decrease in left erector spinae muscle stiffness and left TLF thickness compared to the simulated group. In addition, there was a significant reduction in pain intensity in the MFT group compared to the simulated group at T1 and T2. The results of this study suggest that MFT results in immediate tissue changes and transient pain reduction in patients with LBP.

Immediate Effects of Myofascial Release Treatment on Lumbar Microcirculation: A Randomized, Placebo-Controlled Trial

(1) Background: Inflammatory processes in the thoracolumbar fascia (TLF) lead to thickening, compaction, and fibrosis and are thought to contribute to the development of nonspecific low back pain (nLBP). The blood flow (BF) of fascial tissue may play a critical role in this process, as it may promote hypoxia-induced inflammation. The primary objective of the study was to examine the immediate effects of a set of myofascial release (MFR) techniques on the BF of lumbar myofascial tissue. The secondary objectives were to evaluate the influence of TLF morphology (TLFM), physical activity (PA), and body mass index (BMI) on these parameters and their correlations with each other. (2) Methods: This study was a single-blind, randomized, placebo-controlled trial. Thirty pain-free subjects (40.5 ± 14.1 years) were randomly assigned to two groups treated with MFR or a placebo intervention. Correlations between PA, BMI, and TLFM were calculated at baseline. The effects of MFR and TLFM on BF (measured with white light and laser Doppler spectroscopy) were determined. (3) Results: The MFR group had a significant increase in BF after treatment (31.6%) and at follow-up (48.7%) compared with the placebo group. BF was significantly different between disorganized and organized TLFM (p < 0.0001). There were strong correlations between PA (r = -0.648), PA (d = 0.681), BMI (r = -0.798), and TLFM. (4) Conclusions: Impaired blood flow could lead to hypoxia-induced inflammation, possibly resulting in pain and impaired proprioceptive function, thereby likely contributing to the development of nLBP. Fascial restrictions of blood vessels and free nerve endings, which are likely associated with TLFM, could be positively affected by the intervention in this study.

Biomechanical considerations of the posterior surgical approach to the lumbar spine

BACKGROUND CONTEXT

The effect of the posterior midline approach to the lumbar spine, relevance of inter- and supraspinous ligament (ISL&SSL) sparing, and potential of different wound closure techniques are largely unknown despite their common use.

PURPOSE

The aim of this study was to quantify the effect of the posterior approach, ISL&SSL resection, and different suture techniques.

STUDY DESIGN

Biomechanical cadaveric study.

METHODS

Five fresh frozen human torsi were stabilized at the pelvis in the erect position. The torsi were passively loaded into the forward bending position and the sagittal angulation of the sacrum, L4 and T12 were measured after a level-wise posterior surgical approach from L5/S1 to T12/L1 and after a level-wise ISL&SSL dissection of the same sequence. The measurements were repeated after the surgical closure of the thoracolumbar fascia with and without suturing the fascia to the spinous processes.

RESULTS

Passive spinal flexion was increased by 0.8±0.3° with every spinal level accessed by the posterior approach. With each additional ISL&SSL resection, a total increase of 1.6±0.4° was recorded. Suturing of the thoracolumbar fascia reduced this loss of resistance against lumbar flexion by 70%. If the ISL&SSL were resected, fascial closure reduced the lumbar flexion by 40% only. In both settings, suturing the fascia to the spinous processes did not result in a significantly different result (p=.523 and p=.730 respectively).

CONCLUSION

Each level accessed by a posterior midline approach is directly related to a loss of resistance against passive spinal flexion. Additional resection of ISL&SSL multiplies it by a factor of two.

CLINICAL SIGNIFICANCE

The surgical closure of the thoracolumbar fascia can reduce the above mentioned loss of resistance partially. Suturing the fascia to the spinal processes does not result in improved passive stability.

The Deep Fascia and its Role in Chronic Pain & Pathological Conditions: A Review

INTRODUCTION

The deep fascia is a three-dimensional continuum of connective tissue surrounding the bones, muscles, nerves and blood vessels throughout our body. Its importance in chronically debilitating conditions has recently been brought to light. This work investigates changes in these tissues in pathological settings.

MATERIALS AND METHODS

A state-of-the-art review was conducted in PubMed and Google Scholar following a two-stage process. A first search was performed to identify main types of deep fasciae. A second search was performed to identify studies considering a deep fascia, common pathologies of this deep fascia and the associated alterations in tissue anatomy.

RESULTS

We find that five main deep fasciae pathologies are chronic low back pain, chronic neck pain, Dupuytren's disease, plantar fasciitis and iliotibial band syndrome. The corresponding fasciae are respectively the thoracolumbar fascia, the cervical fascia, the palmar fascia, the plantar fascia and the iliotibial tract. Pathological fascia is characterized by increased tissue stiffness along with alterations in myofibroblast activity and the extra-cellular matrix, both in terms of collagen and Matrix Metalloproteases (MMP) levels. Innervation changes such as increased density and sensitization of nociceptive nerve fibers are observed. Additionally, markers of inflammation such as pro-inflammatory cytokines and immune cells are documented. Pain originating from the deep fascia likely results from a combination of increased nerve density, sensitization and chronic nociceptive stimulation, whether physical or chemical.

CONCLUSIONS

The pathological fascia is characterized by changes in innervation, immunology and tissue contracture. Further investigation is required to best benefit both research opportunities and patient care.

Intermittent pain in patients with chronic low back pain is associated with abnormalities in muscles and fascia

We investigated the relationship between paravertebral muscles and perimuscular connective tissues of the thoracolumbar fascia region and the four types of pain in patients suffering from chronic low back pain. A total of 17 patients with chronic low back pain participated in this study. Ultrasound imaging method was used to measure the thickness and echogenicity of the paravertebral muscles and perimuscular connective tissues. The measurement site considered in this study was located lateral to the midpoint between L2-3 and L4-5 spines. In addition, age, gender, BMI, numerical rating scale and the short-form McGill pain questionnaire 2 (includes questions with respect to continuous pain, intermittent pain, neuropathic pain and affective descriptors) were used for assessment. Statistical analysis was performed using correlation analysis and multiple regression analysis. A significant association was observed between paravertebral muscle echogenicity at L2-3 and the numerical rating scale (r = 0.499), between paravertebral muscle echogenicity at L4-5 with numerical rating scale (r = 0.538) and intermittent pain (r = 0.594), and between perimuscular connective tissue thickness at L2-3 and numerical rating scale (r = 0.762). We observed that the factor influencing perimuscular connective tissue thickness at L2-3 and L4-5 was intermittent pain (β = 0.513, β = 0.597, respectively). It was also observed that some of the imaging findings were associated with age and BMI. In conclusion, we observed that paravertebral muscle echogenicity and perimuscular connective tissue thickness in patients with chronic low back pain were associated with pain, especially intermittent pain.

A systematic review of in vivo stretching regimens on inflammation and its relevance to translational yoga research

OBJECTIVE

To conduct a systematic review evaluating the impact of stretching on inflammation and its resolution using in vivo rodent models. Findings are evaluated for their potential to inform the design of clinical yoga studies to assess the impact of yogic stretching on inflammation and health.

METHODS

Studies were identified using four databases. Eligible publications included English original peer-reviewed articles between 1900-May 2020. Studies included those investigating the effect of different stretching techniques administered to a whole rodent model and evaluating at least one inflammatory outcome. Studies stretching the musculoskeletal and integumentary systems were considered. Two reviewers removed duplicates, screened abstracts, conducted full-text reviews, and assessed methodological quality.

RESULTS

Of 766 studies identified, 25 were included for synthesis. Seven (28%) studies had a high risk of bias in 3 out of 10 criteria. Experimental stretching protocols resulted in a continuum of inflammatory responses with therapeutic and injurious effects, which varied with a combination of three stretching parameters--duration, frequency, and intensity. Relative to injurious stretching, therapeutic stretching featured longer-term stretching protocols. Evidence of pro- and mixed-inflammatory effects of stretching was found in 16 muscle studies. Evidence of pro-, anti-, and mixed-inflammatory effects was found in nine longer-term stretching studies of the integumentary system.

CONCLUSION

Despite the overall high quality of these summarized studies, evaluation of stretching protocols paralleling yogic stretching is limited. Both injurious and therapeutic stretching induce aspects of inflammatory responses that varied among the different stretching protocols. Inflammatory markers, such as cytokines, are potential outcomes to consider in clinical yoga studies. Future translational research evaluating therapeutic benefits should consider in vitro studies, active vs. passive stretching, shorter-term vs. longer-term interventions, systemic vs. local effects of stretching, animal models resembling human anatomy, control and estimation of non-specific stresses, development of in vivo self-stretching paradigms targeting myofascial tissues, and in vivo models accounting for gross musculoskeletal posture.

Development of a common peroneal nerve injury model in domestic swine for the study of translational neuropathic pain treatments

OBJECTIVE

To date, muscular and bone pain have been studied in domestic swine models, but the only neuropathic pain model described in swine is a mixed neuritis model. Common peroneal nerve injury (CPNI) neuropathic pain models have been utilized in both mice and rats.

METHODS

The authors developed a swine surgical CPNI model of neuropathic pain. Behavioral outcomes were validated with von Frey filament testing, thermal sensitivity assessments, and social and motor scoring. Demyelination of the nerve was confirmed through standard histological assessment. The contralateral nerve served as the control.

RESULTS

CPNI induced mechanical and thermal allodynia (p < 0.001 [n = 10] and p < 0.05 [n = 4], respectively) and increased pain behavior, i.e., guarding of the painful leg (n = 12). Myelin protein zero (P0) staining revealed demyelination of the ligated nerve upstream of the ligation site.

CONCLUSIONS

In a neuropathic pain model in domestic swine, the authors demonstrated that CPNI induces demyelination of the common peroneal nerve, which the authors hypothesize is responsible for the resulting allodynic pain behavior. As the anatomical features of domestic swine resemble those of humans more closely than previously used rat and mouse models, utilizing this swine model, which is to the authors' knowledge the first of its kind, will aid in the translation of experimental treatments to clinical trials.

A Role for Superficial Heat Therapy in the Management of Non-Specific, Mild-to-Moderate Low Back Pain in Current Clinical Practice: A Narrative Review

Low back pain (LBP) is a leading cause of disability. It significantly impacts the patient's quality of life, limits their daily living activities, and reduces their work productivity. To reduce the burden of LBP, several pharmacological and non-pharmacological treatment options are available. This review summarizes the role of superficial heat therapy in the management of non-specific mild-to-moderate LBP. First, we outline the common causes of LBP, then discuss the general mechanisms of heat therapy on (LBP), and finally review the published evidence regarding the impact of superficial heat therapy in patients with acute or chronic non-specific LBP. This review demonstrates that continuous, low-level heat therapy provides pain relief, improves muscular strength, and increases flexibility. Therefore, this effective, safe, easy-to-use, and cost-effective non-pharmacological pain relief option is relevant for the management of non-specific mild or moderate low back pain in current clinical practice.

Fascia Mobility, Proprioception, and Myofascial Pain

The network of fasciae is an important part of the musculoskeletal system that is often overlooked. Fascia mobility, especially along shear planes separating muscles, is critical for musculoskeletal function and may play an important, but little studied, role in proprioception. Fasciae, especially the deep epimysium and aponeuroses, have recently been recognized as highly innervated with small diameter fibers that can transmit nociceptive signals, especially in the presence of inflammation. Patients with connective tissue hyper- and hypo-mobility disorders suffer in large number from musculoskeletal pain, and many have abnormal proprioception. The relationships among fascia mobility, proprioception, and myofascial pain are largely unstudied, but a better understanding of these areas could result in improved care for many patients with musculoskeletal pain.

Fear-avoidance beliefs are associated with reduced lumbar spine flexion during object lifting in pain-free adults

ABSTRACT

There is a long-held belief that physical activities such as lifting with a flexed spine is generally harmful for the back and can cause low back pain (LBP), potentially reinforcing fear-avoidance beliefs underlying pain-related fear. In patients with chronic LBP, pain-related fear has been shown to be associated with reduced lumbar range of motion during lifting, suggesting a protective response to pain. However, despite short-term beneficial effects for tissue health, recent evidence suggests that maintaining a protective trunk movement strategy may also pose a risk for (persistent) LBP due to possible pronociceptive consequences of altered spinal motion, potentially leading to increased loading on lumbar tissues. Yet, it is unknown if similar protective movement strategies already exist in pain-free individuals, which would yield potential insights into the role of fear-avoidance beliefs in motor behavior in the absence of pain. Therefore, the aim of this study is to test whether fear-avoidance beliefs influence spinal motion during lifting in a healthy cohort of pain-free adults without a history of chronic pain. The study subjects (N = 57) filled out several pain-related fear questionnaires and were asked to perform a lifting task (5kg-box). High-resolution spinal kinematics were assessed using an optical motion capturing system. Time-sensitive analyses were performed based on statistical parametric mapping. The results demonstrated time-specific and negative relationships between self-report measures of pain-related fear and lumbar spine flexion angles during lifting, indicating potential unfavorable interactions between psychological factors and spinal motion during lifting in pain-free subjects.

Structural remodeling of the lumbar multifidus, thoracolumbar fascia and lateral abdominal wall perimuscular connective tissues: A search for its potential determinants

Recently remodeling of lumbar soft tissues has received increased research attention. However, the major determinants that influence remodeling need to be elucidated in order to understand the impact of different rehabilitation modalities on tissue remodeling. The main aim of this study was to explore the between-subject variance of different measures of lumbar soft tissues quantified with rehabilitative ultrasound imaging (RUSI). RUSI measures (n = 8) were collected from 30 subjects without and 34 patients with LBP: (1) lumbar multifidus (LM) echogenicity (fatty infiltration/fibrosis) at three vertebral levels (L3/L4, L4/L5 and L5/S1) (n = 3); (2) posterior layer thickness of the thoracolumbar fascia (n = 1); and (3) thickness of the fasciae surrounding the external oblique (EO), internal oblique (IO), and transversus abdominis (TrA) (n = 4). Forward stepwise multivariate regression modeling was conducted with these RUSI measures as dependent variables, using the following independent variables as potential determinants: age, sex, the presence of LBP, body size/composition characteristics (height, weight, trunk length, subcutaneous tissue thickness over the abdominal, and LM muscles), trunk muscle function (or activation) as determined with the percent thickness change of LM, EO, IO, and TrA muscles during a standardized effort (RUSI measures), and physical activity level during sport and leisure activities as estimated with a self-report questionnaire. Two or three statistically significant predictors (or determinants) were selected in the regression model of each RUSI measure (n = 8 models), accounting for 26-64% of their total variance. The subcutaneous tissue thickness on the back accounted for 15-30% variance of LM echogenicity measures and thoracolumbar fascia thickness while the subcutaneous tissue thickness over the abdominals accounted for up to 42% variance of the fascia separating the subcutaneous adipose tissues and the EO muscle. The thickness of IO at rest accounted for 13-21% variance of all investigated abdominal fasciae except the fascia separating the subcutaneous adipose tissue and EO. Pain status accounted for 13-18% variance of the anterior and posterior fasciae of the TrA. Age accounted for 11-14% variance of LM echogenicity at all investigated vertebral levels while sex accounted for 15-21% variance of LM echogenicity at L3/L4 and fascia separating subcutaneous adipose tissue and EO muscle. The function (or activation) of EO and LM at L3/L4 accounted for 8-11% variance of the thoracolumbar fascia and fascia separating TrA and intra-abdominal content (TrA posterior fascia), respectively. Finally, the physical activity level during sport activities accounted for 7% variance of the fascia separating the subcutaneous adipose tissues and the EO muscle. These findings suggest that determinants other than body size characteristics may impact the remodeling of lumbar soft tissues, more importantly the subcutaneous adipose tissue deposits (thickness RUSI measures), which are associated with ectopic fat deposition in the LM and in the fasciae that are more closely positioned to the surface. While age, sex, and pain status explain some variability, modifiable factors such as physical activity level as well as trunk muscle thickness and function were involved. Overall, these results suggest that rehabilitation can potentially impact tissue remodeling, particularly in terms of intramuscular and perimuscular adipose tissues.

The morphological and microscopical characteristics of posterior layer of human thoracolumbar fascia; A potential source of low back pain

BACKGROUND

Posterior layer of thoracolumbar fascia (PTLF) is the deep fascia of back of the trunk, which connects the trunk, upper limb and lower limb muscles. Very few cadaveric studies of posterior layer of thoracolumbar fascia (PTLF) are found in the literature, which mention the presence of nerve receptors in it but, quantification of the nerve receptors where not found. Providing the morphological and morphometrical data of PTLF may help the exercise physiologists, sports physicians, occupational health assistants and, physiotherapists to modify or invent new protocol of treatment to help the society.

METHODS

In this study, twenty formalin embalmed human cadavers were used and we have documented the orientation of the PTLF and quantified the number of peripheral nerve endings at the different vertebral levels.

RESULTS

Mean distance of PTLF from vertebral spines to the musculofascial junction was at thoracic region 3.38cm and 3.34cm; at lumbar region, it was 7.4cm and 7.36cm and at sacral region it was 2.98cm and 2.96cm on right and left side, respectively. The angulation of PTLF varies from 18-110 degrees at different vertebral levels. The microscopic data shows the thickness of PTLF and number of nerve endings in the sacral level is increased compared to that of thoracic vertebral levels.

CONCLUSIONS

We have contributed the novel morphological and microscopical details to the limited existing data on PTLF. We also have provided the quantitative data of nerve fibers, which are possible nociceptors of PTLF.

Elasticity standard values of the thoracolumbar fascia assessed with acoustic radiation force impulse elastography on healthy volunteers: A cross section study

INTRODUCTION

Determining the normal values for acoustic radiation force impulse (ARFI) shear wave elastography of the thoracolumbar fascia (TLF) and define possible factors of influence.

METHODS

We measured the shear wave velocity (SWV) in m/s and the diameter (anterior-posterior) in mm of the TLF bilateral in 267 healthy participants with the Acuson S3000™ (Siemens) using the virtual touch image quantification mode (VTIQ). The parameters were tested for correlations with the anthropometric data of the participants, between different age groups and the genders, as well as information obtained from the history, such as smoking and sporting activities.

RESULTS

We determined a mean SWV of 3.28 ± 0.55 m/s for the left thoracolumbar fascia and 3.44 ± 0.55 m/s for the right. The diameter on the right was 2.7 ± 0.8 mm. On the left, it was 2.7 ± 0.9 mm. Neither body mass index (BMI) nor gender had a significant effect on either of the measured parameters (p > 0.05). The same goes for regular medication, sporting activity or the consumption of alcohol (p > 0.05). The results concerning the effect of smoking and age were inconclusive as they only had a significant influence to either the right or the left side of the TLF but not on the other side.

CONCLUSIONS

We collected the normal value for ARFI shear wave elastography of the TLF in 267 healthy participants. Furthermore, neither gender, BMI, sports activity nor the consumption of alcohol affected the elasticity or the diameter of the thoracolumbar fascia.

Quantitative Ultrasound Imaging Differences in Multifidus and Thoracolumbar Fasciae between Athletes with and without Chronic Lumbopelvic Pain: A Case-Control Study

New trends in ultrasound imaging are focused on exploration of morphology and muscle quality. The main goal of the study was to evaluate the first-order descriptor and echostructure of lumbar multifidus at the L4 vertebral level in athletes with and without chronic lumbopelvic pain (CLPP). A case-control study was performed in 15 semiprofessional athletes with CLPP and 15 without (healthy athletes). Lumbar multifidus echointensity and echovariation were measured for muscle quality assessment. Echostructure was used to evaluate lumbar multifidus cross-sectional area (CSA) at resting and during muscle contraction, respective differences during both phases (CSA^Dif.), activation patterns, and thoracolumbar fasciae morphology and thickness. Significant differences with a large effect size were observed in quantitative data from CLPP and healthy athletes for left lumbar multifidus CSA^Dif. and thoracolumbar fasciae morphology. Categorical data showed statistically significant differences with a small-to-moderate effect size for lumbar multifidus activation pattern and thoracolumbar fasciae morphology. Athletes with CLPP showed a reduced CSA difference between lumbar multifidus contraction and at resting and higher disorganization of thoracolumbar fasciae morphology compared to healthy athletes. These findings suggest the importance of dynamic exploration of the lumbar region and connective tissue in sports performance and injury prevention.

Reconnecting the Brain With the Rest of the Body in Musculoskeletal Pain Research

A challenge in understanding chronic musculoskeletal pain is that research is often siloed between neuroscience, physical therapy/rehabilitation, orthopedics, and rheumatology which focus respectively on 1) neurally mediated effects on pain processes, 2) behavior and muscle activity, 3) tissue structure, and 4) inflammatory processes. Although these disciplines individually study important aspects of pain, there is a need for more cross-disciplinary research that can bridge between them. Identifying the gaps in knowledge is important to understand the whole body, especially at the interfaces between the silos-between brain function and behavior, between behavior and tissue structure, between musculoskeletal and immune systems, and between peripheral tissues and the nervous system. Research on "mind and body" practices can bridge across these silos and encourage a "whole person" approach to better understand musculoskeletal pain by bringing together the brain and the rest of the body. PERSPECTIVE: Research on chronic musculoskeletal pain is limited by significant knowledge gaps. To be fully integrated, musculoskeletal pain research will need to bridge across tissues, anatomical areas, and body systems. Research on mind and body approaches encourages a "whole person" approach to better understand musculoskeletal pain.

Establishment of a Novel Porcine Model to Study the Impact of Active Stretching on a Local Carrageenan-Induced Inflammation

OBJECTIVE

Active stretching of the body is integral to complementary mind-body therapies such as yoga, as well as physical therapy, yet the biologic mechanisms underlying its therapeutic effects remain largely unknown. A previous study showed the impact of active stretching on inflammatory processes in rats. The present study tested the feasibility of using a porcine model, with a closer resemblance to human anatomy, to study the effects of active stretching in the resolution of localized inflammation.

DESIGN

A total of 12 pigs were trained to stretch before subcutaneous bilateral Carrageenan injection in the back at the L3 vertebrae, 2 cm from the midline. Animals were randomized to no-stretch or stretch, twice a day for 5 mins over 48 hrs. Animals were euthanized for tissue collection 48 hrs postinjection.

RESULTS

The procedure was well tolerated by the pigs. On average, lesion area was significantly smaller by 36% in the stretch group compared with the no-stretch group (P = 0.03).

CONCLUSION

This porcine model shows promise for studying the impact of active stretching on inflammation-resolution mechanisms. These results are relevant to understanding the stretching-related therapeutic mechanisms of mind-body therapies. Future studies with larger samples are warranted.

Short-Term Effects of Kinesio Taping® on Electromyographic Characteristics of Paraspinal Muscles, Pain, and Disability in Patients With Lumbar Disk Herniation

Context: Kinesio taping® (KT) is a therapeutic modality frequently used in the clinical practice for the treatment of various musculoskeletal disorders. It is often applied in patients with chronic low back pain to decrease pain and improve functional capacity. However, it is not known, whether thoracolumbar fascia KT technique can decrease back pain, restore normal activity of paraspinal muscles, and improve functional capacity in patients with lumbar disk herniation (LDH). Objective: To evaluate the impact of 7-day new KT stabilizing application on lumbar paraspinal muscles function, pain perception, and disability in patients with LDH. Design: A randomized controlled trial. Setting: Human Performance Laboratory. Patients: A number of 38 patients with LDH were randomized into KT (n = 19) and placebo taping (n = 19) groups. Interventions: Both groups received the same "x" type application running over the back along fibers of superficial lamina of the posterior layer of thoracolumbar fascia. Main Outcome Measures: The primary outcome measures were flexion-relaxation and extension-relaxation ratios calculated from electromyographic activity of lumbar multifidus and longissimus thoracic muscles. Pain intensity rating (Quadruple Visual Analogue Scale), pressure pain thresholds of the lower back, Roland-Morris Disability Questionnaire score, back extension force, and flexion range of motion (ROM) were among secondary outcomes. Results: KT application did not affect the lumbar multifidus and longissimus thoracic muscles flexion-relaxation and extension-relaxation ratios, lower back pressure pain thresholds, back flexion ROM, and back extension force (no group × time interaction [GTI]). KT and placebo taping comparably decreased disability level (time effect: F1,36 = 22.817, P < .001; GTI: F1,36 = 0.189, P = .67), average pain (time effect: F1,36 =39.648, P < .001; GTI: F1,36 = 2.553, P = .12), and the worst pain (time effect: F1,36 = 36.039, P < .001; GTI: F1,36 = 0.003, P = .96) intensity. Conclusion: Seven-day KT does not normalize lumbar paraspinal muscle function and is not superior to placebo in reducing disability and pain intensity in patients with LDH.

The indeterminable resilience of the fascial system

The most recent information on fascial tissue indicates that there are not fascial layers, but polyhedral microvacuoles of connective tissue, which connect the body systems and, by hosting specialized cells, permit several functions, such as motor, nervous, vascular and visceral. These microvacuoles (a repetition of polyhedral units of connective fibrils) under internal or external tension change shape and can manage the movement variations, regulating different body functions and ensuring the maintenance of efficiency of the body systems. Their plasticity is based on perfect functional chaos: it is not possible to determine the motion vectors of the different fibrils, which differ in behavior and orientation; this strategy confers to the fascial continuum the maximum level of adaptability in response to the changing internal and external conditions of the cell. The present commentary deals with this concept, providing clinical examples of different disease patterns, providing contrary examples in which this adaptability does not occur, and lastly suggesting considerations for the approach to manipulative therapy of the fascial tissue. The fascial continuum is like a flock of birds flying together without a predetermined logic and maintaining their individuality at the same time.

Acute Surgical Injury Alters the Tensile Properties of Thoracolumbar Fascia in a Porcine Model

Recent work utilizing ultrasound imaging demonstrated that individuals with low back pain (LBP) have increased thickness and decreased mobility of the thoracolumbar fascia (TLF), an indication that the TLF may play a role in LBP. This study used a porcine injury model (microsurgically induced local injury)-shown to produce similar results to those observed in humans with LBP-to test the hypothesis that TLF mechanical properties may also be altered in patients with LBP. Perimuscular TLF tissue was harvested from the noninjured side of vertebral level L3-4 in pigs randomized into either control (n = 5) or injured (n = 5) groups. All samples were tested with a displacement-controlled biaxial testing system using the following protocol: cyclic loading/unloading and stress relaxation tests at 25%, 35%, and then 45% of their resting length. Tissue anisotropy was also explored by comparing responses to loading in longitudinal and transverse orientations. Tissues from injured pigs were found to have greater stretch-stretch ratio moduli (measure of tissue stiffness), less energy dissipation, and less stress decay compared to tissues from control pigs. Responses across these variables also depended on loading orientation.

CLINICAL SIGNIFICANCE

these findings suggest that a focal TLF injury can produce impairments in tissue mechanical properties away from the injured area itself. This could contribute to some of the functional abnormalities observed in human LBP.

Frontiers in fascia research

Basic sciences are the backbone of every clear understanding of how the body is composed and how different structures and functions are connected with each other. It is obvious that there is a huge variability in human beings - not only in terms of the outer appearance such as measurements of height, weight, muscle mass and other physical properties, but also with respect to metabolic and functional parameters. This article highlights recent developments of research activities in the field of fascia sciences with a special emphasis on assessment strategies as the basis of further studies. Anatomical and histological studies show that fascial tissue is highly variable in terms of density, stiffness, and other parameters such as metabolic and humoral activity. Moreover, it encompasses nerves and harbours a system of micro-channels, also known as the primo vascular system. As ultrasound is a widely available method, its use is appealing not only for imaging of fascial structures, but also for thorough scientific analysis. Unlike most other imaging technologies, US has the advantage of real-time analysis of active or passive movements. In addition, other assessment methods for fascial tissue are discussed. In conclusion, fascial tissue plays an important role not only in functional anatomy, but also in evolutionary and molecular biology, sport, and exercise science as well as in numerous therapeutic approaches. A high density of nerves is found in fascial tissue. Knowledge of individual characteristics, especially by visualizing with ultrasound, leads to personalized therapeutic approaches, such as in pain therapy.

Measuring the morphological characteristics of thoracolumbar fascia in ultrasound images: an inter-rater reliability study

Background

Chronic lower back pain is still regarded as a poorly understood multifactorial condition. Recently, the thoracolumbar fascia complex has been found to be a contributing factor. Ultrasound imaging has shown that people with chronic lower back pain demonstrate both a significant decrease in shear strain, and a 25% increase in thickness of the thoracolumbar fascia. There is sparse data on whether medical practitioners agree on the level of disorganisation in ultrasound images of thoracolumbar fascia. The purpose of this study was to establish inter-rater reliability of the ranking of architectural disorganisation of thoracolumbar fascia on a scale from ‘very disorganised’ to ‘very organised’.

Methods

An exploratory analysis was performed using a fully crossed design of inter-rater reliability. Thirty observers were recruited, consisting of 21 medical doctors, 7 physiotherapists and 2 radiologists, with an average of 13.03 ± 9.6 years of clinical experience. All 30 observers independently rated the architectural disorganisation of the thoracolumbar fascia in 30 ultrasound scans, on a Likert-type scale with rankings from 1 = very disorganised to 10 = very organised. Internal consistency was assessed using Cronbach’s alpha. Krippendorff’s alpha was used to calculate the overall inter-rater reliability.

Results

The Krippendorf’s alpha was .61, indicating a modest degree of agreement between observers on the different morphologies of thoracolumbar fascia.The Cronbach’s alpha (0.98), indicated that there was a high degree of consistency between observers. Experience in ultrasound image analysis did not affect constancy between observers (Cronbach’s range between experienced and inexperienced raters: 0.95 and 0.96 respectively).

Conclusions

Medical practitioners agree on morphological features such as levels of organisation and disorganisation in ultrasound images of thoracolumbar fascia, regardless of experience. Further analysis by an expert panel is required to develop specific classification criteria for thoracolumbar fascia.

Investigation of the passive mechanical properties of spine muscles following disruption of the thoracolumbar fascia and erector spinae aponeurosis, as well as facet injury in a rat

BACKGROUND CONTEXT

Muscle tissue is known to remodel in response to changes to its mechanical environment. Alterations in passive mechanical properties of muscles can influence spine stiffness and stability.

PURPOSE

This study aimed to determine whether passive muscle elastic moduli and passive muscle stresses increased 28 days following mechanical disruption of the thoracolumbar fascia and erector spinae aponeurosis, and injury induced by facet joint compression.

STUDY DESIGN

Male Sprague Dawley rats were randomly assigned to three groups (Incision n=8; Injury n=8; and Control n=6).

METHODS

The thoracolumbar fascia and erector spinae aponeurosis were incised in the Incision and Injury groups to expose the left L5-L6 facet joint. In the Injury group, this facet was additionally compressed for three minutes to induce facet injury and cartilage degeneration. Twenty-eight days after surgery, rats were sacrificed and muscle samples were harvested from lumbar and thoracic erector spinae and multifidus for mechanical testing.

RESULTS

Histologic staining revealed mild cartilage degeneration and boney remodeling in the Injury group. However, the hypotheses that either (1) disruption of the thoracolumbar fascia and erector spinae aponeurosis (Incision group) or (2) the addition of facet compression (Injury group) would increase the passive elastic modulus and stress of surrounding muscles were rejected. There was no effect of surgery (Incision or Injury) on the passive elastic modulus (p=.6597). Passive muscle stresses were also not different at any sarcomere length between surgical groups (p>.7043).

CONCLUSION

Disruption of the thoracolumbar fascia and erector spinae aponeurosis and mild facet damage do not lead to measurable changes in passive muscle mechanical properties within 28 days. These findings contribute to our understanding of how spine muscles are affected by injury and fundamental aspects of the initial stages of spine surgery.

Effect of Stretching on Thoracolumbar Fascia Injury and Movement Restriction in a Porcine Model

OBJECTIVE

Stretching of fascia is an important component of manual and movement therapies. We previously showed that in pigs, a unilateral thoracolumbar fascia injury combined with movement restriction (hobble) produced contralateral loss of fascia mobility (shear strain during passive trunk flexion measured with ultrasound) similar to findings in human subjects with chronic low back pain. We now tested whether such abnormalities could be reversed by removing the hobble with or without daily stretching for 1 mo.

DESIGN

Thirty pigs were randomized to control, injury, or injury + hobble for 8 wks. The hobble restricted hip extension ipsilateral to the injury. At week 8, the injury + hobble group was subdivided into continued hobble, removed hobble, and removed hobble + stretching (passively extending the hip for 10 min daily).

RESULTS

Removing hobbles restored normal gait speed but did not restore fascia mobility. Daily passive stretching was not superior to removing hobbles, as there was no significant improvement in fascia mobility with either treatment group (removed hobble or stretching).

CONCLUSIONS

Reduced fascia mobility in response to injury and movement restriction worsens over time and persists even when movement is restored. Reversing fascia abnormalities may require either longer than 1 mo or a different treatment "dose" or modality.

Stretching Reduces Skin Thickness and Improves Subcutaneous Tissue Mobility in a Murine Model of Systemic Sclerosis

Objective

Although physical therapy can help preserve mobility in patients with systemic sclerosis (SSc), stretching has not been used systematically as a treatment to prevent or reverse the disease process. We previously showed in rodent models that stretching promotes the resolution of connective tissue inflammation and reduces new collagen formation after injury. Here, we tested the hypothesis that stretching would impact scleroderma development using a mouse sclerodermatous graft-versus-host disease (sclGvHD) model.

Methods

The model consists in the adoptive transfer (allogeneic) of splenocytes from B10.D2 mice (graft) into Rag2^−/− BALB/c hosts (sclGvHD), resulting in skin inflammation followed by fibrosis over 4 weeks. SclGvHD mice and controls were randomized to stretching in vivo for 10 min daily versus no stretching.

Results

Weekly ultrasound measurements of skin thickness and subcutaneous tissue mobility in the back (relative tissue displacement during passive trunk motion) successfully captured the different phases of the sclGvHD model. Stretching reduced skin thickness and increased subcutaneous tissue mobility compared to no stretching at week 3. Stretching also reduced the expression of CCL2 and ADAM8 in the skin at week 4, which are two genes known to be upregulated in both murine sclGvHD and the inflammatory subset of human SSc. However, there was no evidence that stretching attenuated inflammation at week 2.

Conclusion

Daily stretching for 10 min can improve skin thickness and mobility in the absence of any other treatment in the sclGvHD murine model. These pre-clinical results suggest that a systematic investigation of stretching as a therapeutic modality is warranted in patients with SSc.