Peter O'Sullivan

Altered motor control strategies in subjects with sacroiliac joint pain during the active straight-leg-raise test.

Study Design. An experimental study of respiratory function and kinematics of the diaphragm and pelvic floor in subjects with a clinical diagnosis of sacroiliac joint pain and in a comparable pain-free subject group was conducted. Objective. To gain insight into the motor control strategies of subjects with sacroiliac joint pain and the resultant effect on breathing pattern. Summary of Background Data. The active straight-leg-raise test has been proposed as a clinical test for the assessment of load transfer through the pelvis. Clinical observations show that patients with sacroiliac joint pain have suboptimal motor control strategies and alterations in respiratory function when performing low-load tasks such as an active straight leg raise. Methods. In this study, 13 participants with a clinical diagnosis of sacroiliac joint pain and 13 matched control subjects in the supine resting position were tested with the active straight leg raise and the active straight leg raise with manual compression through the ilia. Respiratory patterns were recorded using spirometry, and minute ventilation was calculated. Diaphragmatic excursion and pelvic floor descent were measured using ultrasonography. Results. The participants with sacroiliac joint pain exhibited increased minute ventilation, decreased diaphragmatic excursion, and increased pelvic floor descent, as compared with pain-free subjects. Considerable variation was observed in respiratory patterns. Enhancement of pelvis stability via manual compression through the ilia reversed these differences. Conclusions. The study findings formally identified altered motor control strategies and alterations of respiratory function in subjects with sacroiliac joint pain. The changes observed appear to represent a compensatory strategy of the neuromuscular system to enhance force closure of the pelvis where stability has been compromised by injury.

Differences in Sitting Postures are Associated With Nonspecific Chronic Low Back Pain Disorders When Patients Are Subclassified

Study Design. A comparative study. Objectives. To investigate sitting postures of asymptomatic individuals and nonspecific chronic low back pain (NS-CLBP) patients (pooled and subclassified) and evaluate the importance of subclassification. Summary of Background. Currently, little evidence exists to support the hypothesis that CLBP patients sit differently from pain-free controls. Although classifying NS-CLBP patients into homogeneous subgroups has been previously emphasized, no attempts have been made to consider such groupings when examining seated posture. Methods. Three angles (sacral tilt, lower lumbar, and upper lumbar) were measured during “usual” and “slumped” sitting in 33 NS-CLBP patients and 34 asymptomatic subjects using an electromagnetic measurement device. Before testing, NS-CLBP patients were subclassified by two blinded clinicians. Twenty patients were classified with a flexion motor control impairment and 13 with an active extension motor control impairment. Results. No differences were found between control and NS-CLBP (pooled) patients during usual sitting. In contrast, analyses based on subclassification revealed that patients classified with an active extension pattern sat more lordotic at the symptomatic lower lumbar spine, whereas patients with a flexion pattern sat more kyphotic, when compared with healthy controls (F = 19.7; df1 = 2, df2 = 63, P < 0.001). Further, NS-CLBP patients had less ability to change their posture when asked to slump from usual sitting (t = 4.2, df = 65; P < 0.001). Conclusions. Differences in usual sitting posture were only revealed when NS-CLBP patients were subclassified. This highlights the importance of subclassifying NS-CLBP patients.

Effect of different upright sitting postures on spinal-pelvic curvature and trunk muscle activation in a pain-free population

Study Design. A normative within-subjects single-group study. Objective. To compare spinal-pelvic curvature and trunk muscle activation in 2 upright sitting postures (“thoracic” and “lumbo-pelvic”) and slump sitting in a pain-free population. Summary of Background Data. Clinical observations suggest that both upright and slump sitting postures can exacerbate low back pain. Little research has investigated the effects of different upright sitting postures on trunk muscle activation. Methods. Spinal-pelvic curvature and surface electromyography of 6 trunk muscles were measured bilaterally in 2 upright (thoracic and lumbo-pelvic) sitting postures and slump sitting in 22 subjects. Results. Thoracic, compared to lumbo-pelvic, upright sitting showed significantly greater thoracic extension (P < 0.001), with significantly less lumbar extension (P < 0.001) and anterior pelvic tilt (P = 0.03). Furthermore, there was significantly less superficial lumbar multifidus (P < 0.001) and internal oblique (P = 0.03) activity, with significantly higher thoracic erector spinae (P < 0.001) and external oblique (P = 0.04) activity in thoracic upright sitting. There was no significant difference in superficial lumbar multifidus activity between thoracic upright and slump sitting. Conclusions. Different upright sitting postures resulted in altered trunk muscle activation. Thoracic when compared to lumbo-pelvic upright sitting involved less coactivation of the local spinal muscles, with greater coactivation of the global muscles. These results highlight the importance of postural training specificity when the aim is to activate the lumbo-pelvic stabilizing muscles in subjects with back pain.

Efficacy of classification-based cognitive functional therapy in patients with non-specific chronic low back pain: A randomized controlled trial

Non‐specific chronic low back pain disorders have been proven resistant to change, and there is still a lack of clear evidence for one specific treatment intervention being superior to another.

Altered patterns of abdominal muscle activation in patients with chronic low back pain

This study investigated patterns of abdominal muscle recruitment during the abdominal drawing in manoeuvre in subjects with chronic low back pain (CLBP) and radiological diagnosis of spondylolysis or spondylolisthesis. Data were collected using surface electromyography from 12 physically active subjects with CLBP and 10 controls. The control subjects displayed an ability to preferentially activate internal oblique with minimal activation of upper rectus abdominis during the action of drawing in the abdominal wall. The group with CLBP were unable to achieve this. This finding may reflect the presence of neuromuscular dysfunction in this group. Further study is required to investigate if these findings are linked to the ability of patients with CLBP to provide dynamic stability of their lumbar spine.

Classification of sagittal thoraco-lumbo-pelvic alignment of the adolescent spine in standing and its relationship to low back pain.

Study Design. A prospective study of the sagittal standing posture of 766 adolescents. Objective. To determine whether posture subgroups based on photographic assessment are similar to those used clinically and to previous, radiographically determined subgroups of sagittal standing posture, and whether identified subgroups are associated with measures of spinal pain. Summary of Background Data. Relatively little research has been performed toward a classification of subjects according to sagittal spinal alignment. Clinical descriptions of different standing posture classifications have been reported, and recently confirmed in a radiographic study. There is limited epidemiological data available to support the belief that specific standing postures are associated with back pain, despite plausible mechanisms. As posture assessment using radiographic methods are limited in large population studies, successful characterization of posture using 2-dimensional photographic images will enable epidemiological research of the association between posture types and spinal pain. Methods. Three angular measures of thoraco-lumbo-pelvic alignment were calculated from lateral standing photographs of subjects with retro-reflective markers placed on bony landmarks. Subgroups of sagittal thoracolumbar posture were determined by cluster analysis of these 3 angular measures. Back pain experience was assessed by questionnaire. The associations between posture subgroups and spinal pain variables were evaluated using logistic regression. Results. Postural subtypes identified by cluster analysis closely corresponded to those subtypes identified previously by analysis of radiographic spinal images in adults and to those described clinically. Significant associations between posture subgroups and weight, height, body mass index, and gender were identified. Those adolescents classified as having non-neutral postures when compared with those classified as having a neutral posture demonstrated higher odds for all measures of back pain, with 7 of 15 analyses being statistically significant. Conclusion. Meaningful classifications exist for adolescent sagittal thoraco-lumbo-pelvic alignment, and these can be determined successfully from sagittal photographs.More neutral thoraco-lumbo-pelvic postures are associated with less back pain.

The influence of different sitting postures on head/neck posture and muscle activity

To date the influence that specific sitting posture has on the head/neck posture and cervico-thoracic muscle activity has been insufficiently investigated. Therefore the aim of this study was to investigate whether three different thoraco-lumbar sitting postures affect head/neck posture and cervico-thoracic muscle activity. Twenty (10 men, 10 women) asymptomatic subjects were placed in 3 standardized thoraco-lumbar sitting postures (lumbo-pelvic, thoracic upright and slump) to investigate their influence on cervico-thoracic muscle activity and head/neck posture. There were significant differences in lumbar and thoracic curvatures in the 3 different sitting postures (P<0.002). Slump sitting was associated with greater head/neck flexion, anterior translation of the head (P<0.001) and increased muscle activity of cervical erector spinae (CES) compared to thoracic and lumbo-pelvic sitting (P=0.001). Thoracic upright sitting showed increased muscle activity of thoracic erector spinae (TES) compared to slump and lumbo-pelvic postures (P=0.015). Upper trapezius (UT) demonstrated no significant difference in muscle activation in the 3 sitting postures (P<0.991). This study demonstrates that different sitting postures affect head/neck posture and cervico-thoracic muscle activity. It highlights the potential importance of thoraco-lumbar spine postural adjustment when training head/neck posture.

It's time for change with the management of non-specific chronic low back pain

Low back pain (LBP) is the second greatest cause of disability in the USA.1 USA data supports that in spite of an enormous increase in the health resources spent on LBP disorders, the disability relating to them continues to increase.2 The management of LBP is underpinned by the exponential increase in the use of physical therapies, opiod medications, spinal injections as well as disc replacement and fusion surgery.2 This is maintained by the underlying belief that LBP is fundamentally a patho-anatomical disorder and should be treated within a biomedical model.1 This is in spite of calls over a number of years to adopt a bio-psycho-social approach, and evidence that only 8–15% of patients with LBP have an identified patho-anatomical diagnosis, resulting in the majority being diagnosed as having non-specific LBP.3 Of this population, a small but significant group becomes chronic and disabled, labelled non-specific chronic low back pain (NSCLBP), consuming a disproportionate amount of healthcare resources.4 1. Over the past decade, the traditional biomedical view of LBP has been greatly challenged. This is a result of: the failure of simplistic single-dimensional therapies to show large effects in patients with NSCLBP5–8; 2. the results of clinical trials testing commonly prescribed interventions demonstrating that no management approaches are clearly superior5–7 9; 3. the stories of NSCLBP patients relating their own ongoing pain experiences of multiple failed treatments, conflicting diagnoses, lost hope and ongoing suffering10; 4. the indisputable evidence supporting the multidimensional nature of NSCLBP as a disorder, where disability levels are more closely associated with cognitive and behavioural aspects of pain rather than sensory and biomedical ones11 12; 5. positive outcomes in randomised controlled trials (RCTs) are best predicted by changes in psychological distress, fear avoidance beliefs, self-efficacy in …

Discriminating healthy controls and two clinical subgroups of nonspecific chronic low back pain patients using trunk muscle activation and lumbosacral kinematics of postures and movements: a statistical classification model.

Study Design. Statistical Classification Model for nonspecific chronic low back pain (NS-CLBP) patients and controls based on parameters of motor control. Objective. Develop a Statistical Classification Model to discriminate between 2 subgroups of NS-CLBP (Flexion Pattern [FP] and Active Extension Pattern [AEP]) and a control group using biomechanical variables quantifying parameters of motor control. Summary of Background Data. It has been well documented that many CLBP patients have motor control impairments of their lumbar spine. O’Sullivan proposed a mechanism-based classification system for NS-CLBP with motor control impairments based on a comprehensive subjective and physical examination to establish the relationship between pain provocation and spinal motor control. For the FP and AEP s, 2 groups defined by O’Sullivan and under investigation is this study, the motor control impairment is considered to be the mechanism maintaining their CLBP. No previous studies have used a Statistical Model with measurements of motor control impairment to subclassify NS-CLBP patients. Methods. Thirty-three NS-CLBP patients (20 FP and 13 AEP) and 34 asymptomatic subjects had synchronized lumbosacral kinematics and trunk muscle activation recorded during commonly reported aggravating postures and movements. Biomechanical variables were quantified and a Statistical Classification Model was developed. Results. The Statistical Model used 5 kinematic and 2 electromyography variables. The model correctly classified 96.4% of cases. Conclusion. Selected biomechanical variables were predictors for subgroup membership and were able to discriminate the 3 subgroups. This study adds further support toward the validation of the proposed classification system.

HEALTH LITERACY AND BELIEFS AMONG A COMMUNITY COHORT WITH AND WITHOUT CHRONIC LOW BACK PAIN

&NA; Health literacy, the ability to seek, understand and utilise health information, is important for good health. Suboptimal health literacy has been associated with poorer health outcomes in many chronic conditions although this has not been studied in chronic low back pain (CLBP). We examined the health literacy of individuals with CLBP using a mixed methods approach. One‐hundred and seventeen adults, comprising 61 with no history of CLBP and 56 with CLBP (28 with low and high disability, respectively, as determined by a median split in Oswestry scores) participated. Data regarding severity of pain, LBP‐related disability, fear avoidance, beliefs about LBP and pain catastrophizing were collected using questionnaires. Health literacy was measured using the Short‐form Test of Functional Health Literacy in Adults (S‐TOFHLA). A sub‐sample of 36 participants with CLBP also participated in in‐depth interviews to qualitatively explore their beliefs about LBP and experiences in seeking, understanding and using information related to LBP. LBP‐related beliefs and behaviours, rather than pain intensity and health literacy skills, were found to be important correlates of disability related to LBP. Individuals with CLBP‐high disability had poorer back pain beliefs and increased fear avoidance behaviours relating to physical activity. Health literacy (S‐TOFHLA) was not related to LBP beliefs and attitudes. Qualitatively, individuals with CLBP‐high disability adopted a more passive coping style and had a pathoanatomic view of their disorder compared to individuals with CLBP‐low disability. While all participants with CLBP had adequate health literacy scores (S‐TOFHLA), qualitative data highlighted difficulties in seeking, understanding and utilising LBP information.