Mieke Dolphens

Increased intramuscular fatty infiltration without differences in lumbar muscle cross-sectional area during remission of unilateral recurrent low back pain

Lumbar muscle degeneration is a common feature in non-specific low back pain (LBP). It is hypothesized that degenerated muscles might compromise spinal stability and lead to further injury/pain. However, little is known about lumbar muscle morphometry after resolution of LBP. Therefore, this study investigated the extent of lumbar muscle atrophy and fatty infiltration in individuals who are at risk for a recurrence of LBP. Thirteen participants in remission of unilateral recurrent LBP were compared to 13 healthy controls, comparable for age, weight, length and level of physical activity. Total, lean muscle and fat cross-sectional area (CSA) of lumbar multifidus (MF), erector spinae (ES) and psoas (PS) were investigated on T1-weighted Magnetic Resonance Imaging (MRI), bilaterally and at 3 lumbar levels (L3 upper, L4 upper and L4 lower endplate). In addition, a muscle-fat-index (MFI) was calculated reflecting the amount of fatty infiltration in lean muscle tissue. No significant differences for total, lean muscle and fat CSA were found between people in remission of recurrent LBP and the control group. Conversely, MFI was increased bilaterally at the 2 lowest lumbar levels. There were no differences between the previously painful and non-painful side of the LBP group for any of the parameters. These results show a generalized increase in intramuscular fatty infiltration in lean muscle tissue in the absence of macroscopical signs of muscle degeneration after resolution of LBP. These findings reflect a decreased muscle quality, but not quantity, and might indicate a pathophysiological mechanism contributing to recurrence of LBP.

A Modern Neuroscience Approach to Chronic Spinal Pain: Combining Pain Neuroscience Education With Cognition-Targeted Motor Control Training

Chronic spinal pain (CSP) is a severely disabling disorder, including nontraumatic chronic low back and neck pain, failed back surgery, and chronic whiplash-associated disorders. Much of the current therapy is focused on input mechanisms (treating peripheral elements such as muscles and joints) and output mechanisms (addressing motor control), while there is less attention to processing (central) mechanisms. In addition to the compelling evidence for impaired motor control of spinal muscles in patients with CSP, there is increasing evidence that central mechanisms (ie, hyperexcitability of the central nervous system and brain abnormalities) play a role in CSP. Hence, treatments for CSP should address not only peripheral dysfunctions but also the brain. Therefore, a modern neuroscience approach, comprising therapeutic pain neuroscience education followed by cognition-targeted motor control training, is proposed. This perspective article explains why and how such an approach to CSP can be applied in physical therapist practice.

Structural and functional brain abnormalities in chronic low back pain: A systematic review ☆

OBJECTIVES The purpose of this systematic review is to analyze the available literature on structural and functional brain abnormalities in chronic low back pain (CLBP) using several brain magnetic resonance imaging (MRI) techniques. METHODS PubMed and Web of Science were systematically screened for relevant literature using different combinations of keywords regarding structural and functional brain imaging techniques in patients with CLBP. Reference lists of included articles were hand-searched for additional literature. Eligible articles were assessed on risk of bias and reviewed by two independent researchers. RESULTS The search query returned 27 articles meeting the inclusion criteria. Methodological quality varied from poor to good. A total of 10 studies evaluated structural gray matter changes. There is conflicting evidence in global gray matter changes, with both increases and decreases shown in different studies. Gray matter changes were demonstrated in specific brain regions. Structural white matter changes were reported in five studies. There is conflicting evidence in total white matter volume due to both increases and unchanged white matter. Several regional differences were identified in which white matter changes were shown. Functional organization during rest was evaluated in 10 studies. CLBP patients showed increased activation in specific regions, together with a disrupted default mode network. A total of six studies evaluated brain activity in response to a nociceptive stimulus. Findings suggest that patients demonstrated increased activity in pain-related regions, and decreased activity in analgesic regions. CONCLUSIONS Overall, there is moderate evidence for regional changes in gray and white matter, together with an altered functional connectivity during rest and increased activity in pain-related areas following painful stimulation, evidencing an upregulated pain matrix. More longitudinal research is needed to clarify the temporal relationship regarding pain and neuroplastic changes, and integration of different brain imaging techniques is warranted.

Use of Muscle Functional Magnetic Resonance Imaging to Compare Cervical Flexor Activity Between Patients With Whiplash-Associated Disorders and People Who Are Healthy

Background Chronic whiplash-associated disorders (WAD) have been shown to be associated with motor dysfunction. Increased electromyographic (EMG) activity in neck and shoulder girdle muscles has been demonstrated during different tasks in participants with persistent WAD. Muscle functional magnetic resonance imaging (mfMRI) is an innovative technique to evaluate muscle activity and differential recruitment of deep and superficial muscles following exercise. Objective The purpose of this study was to compare the recruitment pattern of deep and superficial neck flexors between patients with WAD and controls using mfMRI. Design A cross-sectional design was used. Method The study was conducted in a physical and rehabilitation medicine department. The participants were 19 controls who were healthy (10 men, 9 women; mean [±SD] age=22.2±0.6 years) and 16 patients with WAD (5 men, 11 women; mean [±SD] age=32.9±12.7 years). The T2 values were calculated for the longus colli (Lco), longus capitis (Lca), and sternocleidomastoid (SCM) muscles at rest and following cranio-cervical flexion (CCF). Results In the overall statistical model for T2 shift, there was a significant main effect for muscle (F=3.906, P=.033) but not for group (F=2.855, P=.101). The muscle × group interaction effect was significant (F=3.618, P=.041). Although not significant, there was a strong trend for lesser Lco (P=.061) and Lca (P=.060) activity for the WAD group compared with the control group. Although the SCM showed higher T2 shifts, this difference was not significant (P=.291). Limitations Although mfMRI is an innovative and useful technique for the evaluation of deep cervical muscles, consideration is required, as this method encompasses a postexercise evaluation and is limited to resistance types of exercises. Conclusions Muscle functional magnetic resonance imaging demonstrated a difference in muscle recruitment between the Lco, Lca, and SCM during CCF in the control group, but failed to demonstrate a changed activity pattern in the WAD group compared with the control group. The mild symptoms in the WAD group and the wide variability in T2 values may explain the lack of significance.

Classification system of the normal variation in sagittal standing plane alignment: a study among young adolescent boys

Study Design. Cohort study. Objective. To construct a sagittal standing alignment classification system in which the clinical significance of identified subgroups was considered with spinal pain measures. Summary of Background Data. Numerous grading systems for the categorization of sagittal standing alignment have been devised. However, no common consensus exists about which typology should be adopted. Furthermore, the clinical significance of proposed classification schemes has rarely been assessed in terms of their relationship with spinal pain. Given the importance of the adolescent period for musculoskeletal development, research within a young adolescent population is required. Methods. The study population consisted of 639 prepeak height velocity boys (mean age, 12.6 yr [standard deviation, 0.54 yr]). Sagittal posture was quantified during habitual standing; data were used to develop a classification system according to 3 gross postural and 5 lumbopelvic characteristics. Prevalence rates of spinal pain measures (pain and seeking care) were compared between postural subgroups. Results. Cluster analysis indicated 3 types of characteristic overall sagittal profiles: neutral global alignment (n = 266 [41.6%]), sway-back (n = 199 [31.1%]), and leaning-forward (n = 174 [27.2%]). Within each of these categories, postural subgroups could be established according to specific lumbopelvic features. Logistic regression revealed that prevalence (lifetime and month) of low back pain and neck pain was significantly higher in boys classified as having sway-back posture than in those classified as having neutral global alignment. Spinal pain measures did not differ between groups of the lumbopelvic subclassification. Conclusion. Meaningful classifications exist for sagittal plane posture in young adolescent boys, both on gross body segment and lumbopelvic level. In terms of clinical importance, that is, low back pain and neck pain prevalence, postural subgrouping strategies based on the orientation of gross body segments are suggested to be superior when compared with lumbopelvic grading.

Brain changes associated with cognitive and emotional factors in chronic pain: A systematic review

An emerging technique in chronic pain research is MRI, which has led to the understanding that chronic pain patients display brain structure and function alterations. Many of these altered brain regions and networks are not just involved in pain processing, but also in other sensory and particularly cognitive tasks. Therefore, the next step is to investigate the relation between brain alterations and pain related cognitive and emotional factors. This review aims at providing an overview of the existing literature on this subject. Pubmed, Web of Science and Embase were searched for original research reports. Twenty eight eligible papers were included, with information on the association of brain alterations with pain catastrophizing, fear‐avoidance, anxiety and depressive symptoms. Methodological quality of eligible papers was checked by two independent researchers. Evidence on the direction of these associations is inconclusive. Pain catastrophizing is related to brain areas involved in pain processing, attention to pain, emotion and motor activity, and to reduced top‐down pain inhibition. In contrast to pain catastrophizing, evidence on anxiety and depressive symptoms shows no clear association with brain characteristics. However, all included cognitive or emotional factors showed significant associations with resting state fMRI data, providing that even at rest the brain reserves a certain activity for these pain‐related factors. Brain changes associated with illness perceptions, pain attention, attitudes and beliefs seem to receive less attention in literature.

A clinical postural model of sagittal alignment in young adolescents before age at peak height velocity

IntroductionFrom a clinical point of view, knowledge of customary standing positions among healthy young adolescents is of primary importance. The purpose of this study was to document the correlations between sagittal standing posture parameters in a pre-peak height velocity (pre-PHV) cohort.Materials and methodsThis cohort study included 639 pre-PHV boys (age 12.6 [SD, 0.54] years) and 557 pre-PHV girls (age 10.6 [SD, 0.47] years). Gross body segment orientations and spinopelvic orientation/shape indexes were quantified using a clinical screening protocol. Pearson’s correlation coefficients were determined for all sagittal standing plane alignment parameters, and a postural model was used to analyze the correlations between parameters.ResultsBoth at the gross body segment and spinopelvic level, an interdependence was found between postural parameters. No correlations were observed between ‘global’ parameters related to the pelvis, trunk or body anteroposterior translation postures and ‘local’ spinopelvic geometries. A similar pattern and strength of correlations was obtained in pre-PHV boys and girls, except for the reciprocal relationships between the craniovertebral angle and adjacent anatomic segment characteristics and between thoraco-lumbar geometries.ConclusionsAlthough the correlation schemes do not imply a causal relationship, the proposed postural model allows conjecture about standing posture to be organized slightly differently in pre-PHV boys and girls. Whereas the standing posture in pre-PHV boys might be organized predominantly according to an ascending mode, bottom-up and top-down organizations appear to coexist in pre-PHV girls.

Hip Strength as an Intrinsic Risk Factor for Lateral Ankle Sprains in Youth Soccer Players A 3-Season Prospective Study

Background: Numerous epidemiological studies have emphasized the burden of lateral ankle sprains in youth soccer players. However, no prospective study has identified intrinsic physical and modifiable risk factors for these injuries in this particular population. Although injury prevention programs in soccer incorporate proximal hip and core stability exercises, it is striking that the relationship between impaired proximal hip function and ankle sprains has not yet been prospectively investigated in youth soccer players. Hypothesis: This prospective study aimed to examine whether hip muscle strength is a risk factor for sustaining a lateral ankle sprain in youth soccer players. We hypothesized that decreased hip muscle strength would predispose youth soccer players to an increased risk of lateral ankle sprains. Study Design: Case-control study; Level of evidence, 3. Methods: This study included a total of 133 male youth soccer players (age divisions U11-U17) for analysis. At the beginning of the season, anthropometric characteristics were collected and hip muscle strength was assessed using a handheld dynamometer. Injury registration was performed by the team medical staff during 3 consecutive seasons. A principal-component, multivariate Cox regression analysis was performed to identify potential risk factors for sustaining a lateral ankle sprain. Results: Twelve participants (18% of all reported injuries) sustained a lateral ankle sprain (0.36 per 1000 athletic-exposure hours). After adjustment for body size dependencies and other hip muscle forces, an increase in hip muscle extension force was associated with a significant decrease in the hazard of the injury (hazard ratio, 0.3; 95% confidence interval, 0.1-0.9; P = .028). No other study variable could be identified as a risk factor for lateral ankle sprains. Conclusion: Reduced hip extension muscle strength is an independent risk factor for lateral ankle sprains in male youth soccer players. Other hip muscle strength outcomes were not identified as risk factors. Replication in larger samples with more injured cases is warranted to further ascertain the importance of this risk factor.

Influence of different stool types on muscle activity and lumbar posture among dentists during a simulated dental screening task

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 posture during dental screening, the Ghopec is considered the most suitable design for the tasks undertaken.

Blended-Learning Pain Neuroscience Education for People With Chronic Spinal Pain: Randomized Controlled Multicenter Trial

Background. Available evidence favors the use of pain neuroscience education (PNE) in patients with chronic pain. However, PNE trials are often limited to small sample sizes and, despite the current digital era, the effects of blended‐learning PNE (ie, the combination of online digital media with traditional educational methods) have not yet been investigated. Objective. The study objective was to examine whether blended‐learning PNE is able to improve disability, catastrophizing, kinesiophobia, and illness perceptions. Design. This study was a 2‐center, triple‐blind randomized controlled trial (participants, statistician, and outcome assessor were masked). Setting. The study took place at university hospitals in Ghent and Brussels, Belgium. Participants. Participants were 120 people with nonspecific chronic spinal pain (ie, chronic neck pain and low back pain). Intervention. The intervention was 3 sessions of PNE or biomedically focused back/neck school education (addressing spinal anatomy and physiology). Measurements. Measurements were self‐report questionnaires (Pain Disability Index, Pain Catastrophizing Scale, Tampa Scale for Kinesiophobia, Illness Perception Questionnaire, and Pain Vigilance and Awareness Questionnaire). Results. None of the treatment groups showed a significant change in the perceived disability (Pain Disability Index) due to pain (mean group difference posteducation: 1.84; 95% CI = −2.80 to 6.47). Significant interaction effects were seen for kinesiophobia and several subscales of the Illness Perception Questionnaire, including negative consequences, cyclical time line, and acute/chronic time line. In‐depth analysis revealed that only in the PNE group were these outcomes significantly improved (9% to 17% improvement; 0.37 ≤ Cohen d ≥ 0.86). Limitations. Effect sizes are small to moderate, which might raise the concern of limited clinical utility; however, changes in kinesiophobia exceed the minimal detectable difference. PNE should not be used as the sole treatment modality but should be combined with other treatment strategies. Conclusions. Blended‐learning PNE was able to improve kinesiophobia and illness perceptions in participants with chronic spinal pain. As effect sizes remained small to medium, PNE should not be used as a sole treatment but rather should be used as a key element within a comprehensive active rehabilitation program. Future studies should compare the effects of blended‐learning PNE with offline PNE and should consider cost‐effectiveness.