Paraspinal Muscles

The spinal column is rarely affected by hydatid cyst; however, when involved, it has higher rates of recurrence particularly in case of osseous and paravertebral extensions. We report a 36-year-old patient. The patient was operated previously for hydatid cyst through laminectomy 13 years ago. After 13 years of surgery, the patient was admitted to our clinic with progressive paraparesis. Radiological evaluation revealed multicystic lesions affecting T4 and T5 vertebrae as well as the posterior thoracic wall and paravertebral musculature. Serological findings were also compatible with a hydatid cyst. The patient underwent surgical treatment; the cystic lesions were removed, and vertebral stabilization was provided. The treatment of hydatid cyst in the spine is challenging. Particularly in cases with vertebral involvement, spinal instability and recurrence are the main handicap. Preoperative and postoperative antihelminthic treatment as well as close clinical, radiological and serologi...

This narrative review investigated imaging parameters of the paraspinal muscles and their association with spinal degenerative features and low back pain (LBP) found in the literature. Three principal signs of muscle degeneration were detected on imaging: decreased muscle size, decreased radiographic density, and increased fat deposits. Men have a higher density of paraspinal muscles than women, younger individuals have a higher density than older ones, and lean individuals have a higher density than those with an increased body mass index. Fatty infiltration appears to be a late stage of muscular degeneration and can be measured noninvasively by an MRI scan. Fatty infiltration in the lumbar multifidus is common in adults and is strongly associated with LBP, especially in women, independent of body composition. Fatty infiltration develops in areas where most degenerative changes are found. MR spectroscopy studies have corroborated that the lumbar multifidus in LBP subjects has a sig...

Background: Low back pain is often associated with increased spinal stiffness which thought to arise from increased muscle activity. Unfortunately, the association between paraspinal muscle activity and paraspinal stiffness, as well as the spatial distribution of this relation, is unknown. The purpose of this
investigation was to employ new technological developments to determine the relation between spinal muscle contraction and spinal stiffness over a large region of the lumbar spine.
Methods: Thirty-two male subjects performed graded isometric prone right hip extension at four different exertion levels (0%, 10%, 25% and 50% of the maximum voluntary contraction) to induce asymmetric back muscle activity. The corresponding stiffness and muscle activity over bilateral paraspinal lumbar
regions was measured by indentation loading and topography surface electromyography, respectively. Paraspinal stiffness and muscle activity were then plotted and their correlation was determined.

Findings: Data from this study demonstrated the existence of an asymmetrical gradient in muscle activation and paraspinal stiffness in the lumbar spine during isometric prone right hip extension. The magnitude and scale of the gradient increased with the contraction force. A positive correlation between
paraspinal stiffness and paraspinal muscle activity existed irrespective of the hip extension effort (Pearson correlation coefficient, range 0.566–0.782 (P < 0.001)).

Interpretation: Our results demonstrate the creation of an asymmetrical gradient of muscle activity and paraspinal stiffness during right hip extension. Future studies will determine if alterations in this gradient may possess diagnostic or prognostic value for patients with low back pain.

Forward Head Posture (FHP) may be associated with neck pain and poor health-related quality of life. Literature describes only qualitative muscle length changes associated with FHP. To quantify how muscle-tendon unit lengths are altered when human cadaveric specimens are placed in alignments representing different severities of FHP. Biomechanical study using 13 fresh-frozen cadaveric cervical spine specimens (Occiput-T1, 54±15yrs). Specimens&#39; postural changes simulating increasing FHP severity while maintaining horizontal gaze were assessed. Specimen-specific anatomic models derived from CT-based anatomic data were combined with postural data and specimen-specific anatomy of muscle attachment points to estimate the muscle length changes associated with FHP. FHP was associated with flexion of the mid-lower cervical spine and extension of the upper cervical (sub-occipital) spine. Muscles that insert on the cervical spine and function as flexors (termed &quot;cervical flexors&quot;...

The axial musculoskeletal system of quadrupedal mammals is not currently well understood despite its functional importance in terms of facilitating postural stability and locomotion. Here we examined the detailed architecture of the muscles of the vertebral column of two breeds of dog, the Staffordshire bull terrier (SBT) and the racing greyhound, which have been selectively bred for physical combat and high speed sprint performance, respectively. Dissections of the epaxial musculature of nine racing greyhounds and six SBTs were carried out; muscle mass, length, and fascicle lengths were measured and used to calculate muscle physiological cross-sectional area (PCSA), and to estimate maximum muscle potential for force, work and power production. The longissimus dorsi muscle was found to have a high propensity for force production in both breeds of dog; however, when considered in combination with the iliocostalis lumborum muscle it showed enhanced potential for production of power an...

Forward Head Posture (FHP) may be associated with neck pain and poor health-related quality of life. Literature describes only qualitative muscle length changes associated with FHP. To quantify how muscle-tendon unit lengths are altered when human cadaveric specimens are placed in alignments representing different severities of FHP. Biomechanical study using 13 fresh-frozen cadaveric cervical spine specimens (Occiput-T1, 54±15yrs). Specimens&#39; postural changes simulating increasing FHP severity while maintaining horizontal gaze were assessed. Specimen-specific anatomic models derived from CT-based anatomic data were combined with postural data and specimen-specific anatomy of muscle attachment points to estimate the muscle length changes associated with FHP. FHP was associated with flexion of the mid-lower cervical spine and extension of the upper cervical (sub-occipital) spine. Muscles that insert on the cervical spine and function as flexors (termed &quot;cervical flexors&quot;...

This narrative review investigated imaging parameters of the paraspinal muscles and their association with spinal degenerative features and low back pain (LBP) found in the literature. Three principal signs of muscle degeneration were detected on imaging: decreased muscle size, decreased radiographic density, and increased fat deposits. Men have a higher density of paraspinal muscles than women, younger individuals have a higher density than older ones, and lean individuals have a higher density than those with an increased body mass index. Fatty infiltration appears to be a late stage of muscular degeneration and can be measured noninvasively by an MRI scan. Fatty infiltration in the lumbar multifidus is common in adults and is strongly associated with LBP, especially in women, independent of body composition. Fatty infiltration develops in areas where most degenerative changes are found. MR spectroscopy studies have corroborated that the lumbar multifidus in LBP subjects has a sig...

The purposes of this study were to (1) measure the thickness of cervical multifidus muscle (CMM) in different maximal voluntary contraction percentages of isometric contraction of shoulder muscles, (2) evaluate the differences of the CMM thickness in different directions of the shoulder movement, and (3) compare the changes in the CMM thickness of participants with neck pain and also of healthy individuals. Twenty healthy men (age, 27.45 ± 4.37 years; height, 177 ± 4.66 cm; weight, 72.85 ± 6.46 kg) and 20 men with chronic mechanical neck pain (age, 28.90 ± 5.53 years; height, 176 ± 5.98 cm; weight, 73.15 ± 7.82 kg) participated in the study. Both the right and left CMM thicknesses were measured using an ultrasound device while participants performed isometric contraction of shoulder muscles in 6 movement directions. In both groups, an increment of CMM thickness followed as the increase of isometric force (P &lt; .01).The increase of muscle thickness of healthy participants was subst...

STUDY DESIGN: Reliability study
OBJECTIVES: To compare the within- and between-day intra-rater reliability of rehabilitative ultrasound imaging (RUSI) using static images (RUSIs) and video clips (RUSIvc) in quantifying multifidus muscle thickness at rest and while contracted. The secondary objectives were to compare the measurement precision of averaging multiple measures, and the reliability estimates in individuals with and without low back pain (LBP).
BACKGROUND: Although intra-rater reliability of RUSIs in measuring multifidus thickness has been established, using RUSIvc may improve reliability estimates as examiners may select the optimal image from the video clip. Further, multiple measurements, and LBP status may affect RUSI reliability estimates.
METHODS: RUSIs and RUSIvc were used to quantify multifidus muscle thickness at rest and during contraction, and percent thickness change in 27 volunteers (13 without LBP, and 14 with LBP). Three RUSIs and three RUSIvc were collected in each of two sessions 1 to 4 days apart. Reliability and precision were assessed using intraclass correlation coefficients (ICC), standard error of measurement, minimal detectable change, bias and 95% limits of agreement.
RESULTS: Using an average of two measures yielded optimal measurement precision for RUSIs and RUSIvc. Based on the average of two measures obtained under the same circumstance, there was no significant difference in the reliability estimates between RUSIs and RUSIvc across all testing conditions. Reliability point estimates (ICC3,2) of multifidus thickness were 0.99 for within-day comparisons and ranged from 0.93 to 0.98 for between-day comparisons. The within- and between-day ICC3,2 of percent thickness change ranged from 0.97 to 0.99, and 0.80 to 0.90, respectively. The exploratory analysis showed no significant difference in the reliability estimates between asymptomatic and LBP participants across most testing conditions.
CONCLUSION: Both RUSI methods yielded high reliability estimates for multifidus muscle measurements. Using the average of two measures obtained optimal measurement precision. Overall, RUSIvc is a reliable surrogate of RUSIs for multifidus muscle measurements with an additional advantage of shorter duration of data collection.
KEY WORDS: low back pain, LM, reproducibility, RUSI, ultrasonography

Whereas in the past dental stools typically facilitated a 90° hip angle, a number of currently available alternative designs allow for a more extended hip posture. The present study investigated the influence of different stool types on muscle activity and lumbar posture. Twenty five participants completed a simulated dental procedure on a standard stool, a saddle and the Ghopec. The latter stool comprises a seat pan consisting of a horizontal rear part for the pelvis and an inclinable sloping down front part for the upper legs, with a vertically and horizontally adjustable back rest. Lumbar posture was most close to neutral on the Ghopec, whereas sitting on a standard/saddle stool resulted in more flexed/extended postures respectively. Sitting with a 90° angle (standard stool) resulted in higher activation of back muscles while sitting with a 125° angle (saddle and Ghopec) activated abdominal muscles more, although less in the presence of a backrest (Ghopec). To maintain neutral po...

Traumatic brain injury (TBI) is a common disabling condition with limited treatment options. Diffusion tensor imaging (DTI) measures recovery of axonal injury in white matter (WM) tracts after TBI. Growth hormone deficiency (GHD) after TBI may impair axonal and neuropsychological recovery, and serum IGF-I may mediate this effect. We conducted a longitudinal study to determine the effects of baseline serum IGF-I concentrations on WM tract and neuropsychological recovery after TBI. Thirty-nine adults after TBI (84.6% male; age median 30.5y; 87.2% moderate-severe; time since TBI median 16.3 months, n=4 with GHD) were scanned twice, 13.3 months (12.1-14.9) apart, and 35 healthy controls scanned once. Symptom and quality of life questionnaires and cognitive assessments were completed at both visits (n=33). Our main outcome measure was fractional anisotropy (FA), a measure of WM tract integrity, in a priori regions of interest: splenium of corpus callosum (SPCC), and posterior limb of int...

Microgravity-induced lumbar paraspinal muscle deconditioning may contribute to back pain commonly experienced by astronauts, and may increase the risk of postflight injury. We hypothesized that a combined resistance and aerobic exercise countermeasure protocol that included spinal loading would mitigate lumbar paraspinal muscle deconditioning during 60-days of bed rest in women. Sixteen women underwent 60-day, 6° head-down-tilt bed rest and were randomized into control and exercise groups. During bed rest, the control group performed no exercise. The exercise group performed supine treadmill exercise within lower body negative pressure (LBNP) for 3-4 d/wk and flywheel resistive exercise for 2-3 d/wk. Paraspinal muscle cross-sectional area (CSA) was measured using a lumbar spine MRI sequence before and after bed rest (BR). In addition, isokinetic spinal flexion and extension strengths were measured before and after BR. Data are presented as mean ± SD. Total lumbar paraspinal muscle C...

Firefighting is a dangerous occupation with a high incidence of low back pain and injury. Abnormal back muscle function and morphology has been linked to low back pain and poor physical performance. The effect of exercise training on back muscle size and symmetry has not been investigated in firefighters. The purpose of this study was to assess the effect of worksite exercise training for eliciting lumbar multifidus muscle hypertrophy in firefighters. A cluster randomized controlled trial was conducted with healthy, career firefighters (n=64) from a medium-sized fire department. Participants were randomized by fire station to exercise training (n=36) (supervised back and core exercise performed on duty, 2X/week, 24 weeks) or control (n=28). The cross-sectional area (CSA) of the L4 and L5 lumbar multifidus muscle was assessed with ultrasonography at baseline and following the intervention. At 24 weeks, no significant differences were noted between the groups in the adjusted (by basel...

Evidence is lacking on whether fat infiltration in the multifidus muscles affects outcomes after total disc replacement (TDR) surgery and if it develops after surgery. The aims of this study were 1) to investigate whether pre-treatment multifidus muscle fat infiltration predicts outcome 2 years after treatment with TDR surgery or multidisciplinary rehabilitation, and 2) to compare changes in multifidus muscle fat infiltration from pre-treatment to 2-year follow-up between the two treatment groups. The study is secondary analysis of data from a trial with 2-year follow-up of patients with chronic low back pain (LBP) and degenerative disc randomized to TDR surgery or multidisciplinary rehabilitation. We analyzed (aim 1) patients with both magnetic resonance imaging (MRI) at pre-treatment and valid data on outcome measures at 2-year follow-up (predictor analysis), and (aim 2) patients with MRI at both pre-treatment and 2-year follow-up. Outcome measures were visual analogue scale (VAS)...

Dynamic X-rays (DXR) are widely recognized as an effective method to detect lumbar instability (LI). They are usually performed with the patient in standing position (SDXR). In our opinion, standing position inhibits micromovements of the lumbar segment interested by the listhesis, thanks to paravertebral muscles antalgic contraction and augmented tone. We aim to demonstrate that DXR in recumbent position (RDXR), reducing the action of paravertebral muscles, can discover hypermovements not evidenced in SDXR. Between January 2011 and January 2013, we studied 200 consecutive patients with lumbar degenerative disease with MRI, SDXR, and RDXR. We aimed to find a correlation between low back or radicular pain and the presence of a spondylolisthesis not showed by the SDXR, but showed by the RDXR. We analysed 200 patients: of the 133 not pathologic in SDXR, 43 patients (32.3 %) showed an hypermovement in RDXR (p = 0.0001) without any significant correlation between hidden listhesis and age...

To (1) assess the intra- and inter-rater reliability of different ultrasound (US) measures of the lumbar multifidus muscle in subjects with and without chronic low back pain and (2) test 3 different ways to enhance reliability, that is, by testing different tasks, using a template, and averaging trials within or between days. Cross-sectional repeated-measures design. Laboratory setting. Fifteen subjects with chronic low back pain and 15 control subjects. Subjects (n = 30) performed contralateral arm lifting and contralateral leg lifting while in the prone position. Two 7-second videos of the lumbar multifidus (from rest to contraction) were collected with and without a template (transparency) to reposition the transducer on the skin. One of the two raters repeated the testing 7 to 14 days later to assess intrarater reliability in addition to inter-rater reliability. Reliability was assessed with the generalizability theory as a framework. US imaging measures of the lumbar multifidus thickness were obtained in patients at rest and during standardized contractions (hereafter called primary measures) at 2 vertebral levels and on both sides. These primary measures were used to calculate different, potentially useful US parameters (hereafter called derived measures). Intrarater reliability was better than inter-rater reliability, and primary measures were more reliable than derived measures. The tasks investigated showed comparable reliability results, and the use of the transducer position template was not effective to increase reliability. Averaging the measures of 3 images increased reliability substantially. Optimal reliability requires the use of a single rater and the averaging of at least 3 images per visit. In these conditions, primary measures reach acceptable levels of reliability, which was more difficult to achieve for most derived measures. Arm or leg lifting tasks showed similar reliability, and thus the arm-lifting task is recommended for comparisons with previous studies. The use of a transducer position template is not recommended.

Cervical spondylotic myelopathy (CSM) is among the most common spinal cord disorders of the elderly. Muscle fat infiltration (MFI), a potential pathological sign of muscle adiposity, may contribute to or be associated with pain/disability/impairments in patients with CSM. We examined the relationship between MFI and CSM&#39;s clinical manifestations by enrolling nine CSM patients and five aged-matched controls to undergo MRI imaging of the cervical spine with MFI. A blinded investigator calculated MFI for each of the bilateral multifidii muscles from C3 to C7 on the MRI images. Nurick scores, Neck Disability Index, and modified Japanese Orthopedic Association scores were collected for all patients. CSM patients and controls were equivalent with respect to age, height, weight, gender, race, smoking status, and employment status. MFI was higher in patients with CSM than in controls (31.7% v. 24.6%, respectively, p = 0.0178). Higher MFI was associated with increased disability on the N...