Optimal postural control is an essential capacity in daily life and can be highly variable. The purpose of this study was to investigate if young people have the ability to choose the optimal postural control strategy according to the postural condition and to investigate if non-specific low back pain (NSLBP) influences the variability in proprioceptive postural control strategies. Young individuals with NSLBP (n = 106) and healthy controls (n = 50) were tested on a force plate in different postural conditions (i.e., sitting, stable support standing and unstable support standing). The role of proprioception in postural control was directly examined by means of muscle vibration on triceps surae and lumbar multifidus muscles. Root mean square and mean displacements of the center of pressure were recorded during the different trials. To appraise the proprioceptive postural control strategy, the relative proprioceptive weighting (RPW, ratio of ankle muscles proprioceptive inputs vs. back muscles proprioceptive inputs) was calculated. Postural robustness was significantly less in individuals with NSLBP during the more complex postural conditions (p < 0.05). Significantly higher RPW values were observed in the NSLBP group in all postural conditions (p < 0.05), suggesting less ability to rely on back muscle proprioceptive inputs for postural control. Therefore, healthy controls seem to have the ability to choose a more optimal postural control strategy according to the postural condition. In contrast, young people with NSLBP showed a reduced capacity to switch to a more multi-segmental postural control strategy during complex postural conditions, which leads to decreased postural robustness.
Introduction: Illness Perceptions (IPs) may play a role in the management of persistent low back pain. The mediation and/or moderation effect of IPs on primary outcomes in physiotherapy treatment is unknown. Methods: A multiple single-case experimental design, using a matched care physiotherapy intervention, with three phases (phases A-B-A’) was used including a 3 month follow up (phase A’). Primary outcomes: pain intensity, physical functioning and pain interference in daily life. Analyzes: linear mixed models, adjusted for fear of movement, catastrophizing, avoidance, sombreness and sleep. Results: Nine patients were included by six different primary care physiotherapists. Repeated measures on 196 data points showed that IPs Consequences, Personal control, Identity, Concern and Emotional response had a mediation effect on all three primary outcomes. The IP Personal control acted as a moderator for all primary outcomes, with clinically relevant improvements at 3 month follow up. Conclusion: Our study might indicate that some IPs have a mediating or a moderating effect on the outcome of a matched care physiotherapy treatment. Assessing Personal control at baseline, as a relevant moderator for the outcome prognosis of successful physiotherapy management of persistent low back pain, should be further eplored.
Background: Observing and analyzing movement quality (MQ) in patients with non-specific low back pain (NS-LBP) is important in the clinical reasoning of primary care physiotherapists and exercise therapists. However, there is no standardized form of assessment. Research question: which MQ domains are measured with which instruments, and which activities are relevant, appropriate and methodologically sound for assessing MQ in patients with NS-LBP?Methods: The study had three phases. In phase 1 we conducted a systematic review in PubMed, CINAHL and SPORTDiscus of literature published until October 2018. The selected studies measured MQ domains with instruments that enabled us to 1) compare MQ in self-paced dynamic activities of patients with NS-LBP and healthy controls, and/or 2) determine change over time of MQ in patients with NS-LBP. In phase 2 we established relevant dynamic activities to assess in patients with NS-LBP. In phase 3 we determined appropriateness and methodological qualities of the selected instruments.Results: Thirty cross-sectional and three pre-post-test studies were eligible. The instruments consisted of complex (n = 19) and simple (n = 7) instrumented motion analysis systems and standardized observational tests (n = 7). We identified three domains representative for MQ: range of motion (ROM), inter-segmental coordination, and whole-body movements. In these domains, patients with NS-LBP significantly differed from healthy controls, respectively 7/12, 12/13 and 13/20 studies. Moreover, ROM and whole-body movements significantly improved over time in patients with NS-LBP (3/3 studies). Based on phase 3, we concluded that none of the instruments are appropriate to assess MQ in patients with NS-LBP in primary care.Significance: Forward bending, lifting, and walking seem the most relevant activities to evaluate in patients with NS-LBP. However, we found no suitable instruments to measure ROM, inter-segmental coordination, or whole-body movements as determinants of MQ in these activities in daily practice. We therefore recommend such an instrument be developed.
