How do we stand? Variations during repeated standing phases of asymptomatic subjects and low back pain patients

Marked differences between continuous long-term and clinical snapshot examinations: is the current standard of back pain diagnostics outdated?

Current clinical examination of low back pain (LBP) patients primarily relies on static clinical examinations, which rarely represent the dynamic postures patients adopt during daily activities. To gain an overview on the dynamic kinematics-kinetics changes over a day, the lumbar back kinematics of asymptomatic individuals and LBP patients were measured over 24 h, and the passively resisted bending and torsional moments were estimated. 208 asymptomatic subjects (115 females) and 116 LBP patients (71 females) were analysed. Compared to static upright standing, the mean lumbar lordosis of asymptomatic subjects drops significantly by 21° during everyday life (p < 0.01). Maximum bending moments of 44.0-50.6 Nm were estimated at the L2-L3. LBP patients showed significantly lower (p < 0.01) lumbar flattening during daily life of about 16°. Maximum bending moments of 27-52 Nm were found at the L3-L4. The initial static upright lumbar lordosis was significantly lower in LBP population (by 6°) resulting in almost similar average lumbar shapes during daily activities in both groups. The torsional movements were with 2.2° greatest in L1-L2 independent of sex (p = 0.19) and LBP (p = 0.54) with moments of 6-16 Nm. The lumbar profile and associated internal moments during daily life differ substantially from those recorded during clinical examinations. LBP patients demonstrates significantly lower lordosis at the snapshot assessment and significantly lower movement variations and internal moments during daily life. Only the dynamic long-term assessments unravelled a less flexed posture in LBP population. Apparently, such a reduced dynamic flexed posture indicates a compensatory habit for pain relief.

Effect of personalized spinal profile on its biomechanical response in an EMG-assisted optimization musculoskeletal model of the trunk

Recent developments in musculoskeletal (MS) modeling have been geared towards model customization. Personalization of the spine profile could affect estimates of spinal loading and stability, particularly in the upright standing posture where large inter-subject variations in the lumbar lordosis have been reported. This study investigates the biomechanical consequences of changes in the spinal profile. In 31 participants (healthy and with back pain), (1) the spine external profile was measured, (2) submaximal contractions were recorded in a dynamometer to calibrate the EMG-driven MS model and finally (3) static lifting in the upright standing challenging spine stability while altering load position and magnitude were considered. EMG signals of 12 trunk muscles and angular kinematics of 17 segments were recorded. For each participant, the MS model was constructed using either a generic or a personalized spinal profile and 17 biomechanical outcomes were computed, including individual muscle forces, ratios of muscle group forces, spinal loading and stability parameters. According to the ANOVA results and corresponding effect sizes, personalizing the spine profile induced medium and large effects on about half MS model outcomes related to the trunk muscle forces and negligible to small effects on spinal loading and stability as more aggregate outcomes. These effects are explained by personalized spine profiles that were a little more in extension as well as more pronounced spine curvatures (lordosis and kyphosis). These findings suggest that spine profile personalization should be considered in MS spine modeling as it may impact muscle force prediction and spinal loading.

Validity of evaluating spinal kinetics without participant-specific kinematics

Musculoskeletal models are commonly used to estimate in vivo spinal loads under various loading conditions. Typically, participant-specific measured kinematics (PSMK) are coupled with participant-specific models, but obtaining PSMK data can be costly and infeasible in large studies or clinical practice. Thus, we evaluated two alternative methods to estimate spinal loads without PSMK: 1) ensemble average kinematics (EAK) based on kinematics from all participants; and 2) using separately measured individual kinematics (SMIK) from multiple other participants as inputs, then averaging the resulting loads. This study compares the dynamic spine loading patterns and peak loads in older adults performing five lifting tasks using PSMK, EAK and SMIK. Median root mean square errors of EAK and SMIK methods versus PSMK ranged from 18 to 72% body weight for compressive loads and from 2 to 25% body weight for shear loads, with median cross-correlations ranging from 0.931 to 0.991. The root mean square errors and cross-correlations between repeated PSMK trials fell within similar ranges. Compressive peak loads evaluated by EAK and SMIK were not different than PSMK in 12 of 15 cases, while by comparison repeated PSMK trials were not different in 13 of 15 cases. Overall, the resulting spine loading magnitudes and profiles using EAK or SMIK were not notably different than using a PSMK approach, and differences were not greater than between two PSMK trials. Thus, these findings indicate that these approaches may be used to make reasonable estimates of dynamic spinal loading without direct measurement of participant kinematics.

Differences in lumbar spine intradiscal pressure between standing and sitting postures: a comprehensive literature review

Background

Musculoskeletal disorders (MSDs), especially in the lumbar spine, are a leading concern in occupational health. Work activities associated with excessive exposure are a source of risk for MSDs. The optimal design of workplaces requires changes in both sitting and standing postures. In order to secure such a design scientifically proved quantitative data are needed that would allow for the assessment of differences in spine load due to body posture and/or exerted force. Intradiscal pressure (IP) measurement in the lumbar spine is the most direct method of estimating spinal loads. Hence, this study aims at the quantitative evaluation of differences in lumbar spine load due to body posture and exerted forces, based on IP reported in publications obtained from a comprehensive review of the available literature.

Methodology

In order to collect data from studies measuring IP in the lumbar spine, three databases were searched. Studies with IP for living adults, measured in various sitting and standing postures, where one of these was standing upright, were included in the analysis. For data to be comparable between studies, the IP for each position was referenced to upright standing. Where different studies presented IP for the same postures, those relative IPs (rIP) were merged. Then, an analysis of the respective outcomes was conducted to find the possible relationship of IPs dependent on a specific posture.

Results

A preliminary analysis of the reviewed papers returned nine items fulfilling the inclusion and exclusion criteria. After merging relative IPs from different studies, rIP for 27 sitting and 26 standing postures was yielded. Some of the data were useful for deriving mathematical equations expressing rIP as a function of back flexion angle and exerted force in the form of a second degree polynomial equation for the standing and sitting positions. The equations showed that for the standing posture, the increase in IP with increasing back flexion angle is steeper when applying an external force than when maintaining body position only. In a sitting position with the back flexed at 20°, adding 10 kg to each hand increases the IP by about 50%. According to the equations developed, for back flexion angles less than 20°, the IP is greater in sitting than in standing. When the angle is greater than 20°, the IP in the sitting position is less than in the standing position at the same angle of back flexion.

Conclusions

Analysis of the data from the reviewed papers showed that: sitting without support increases IP by about 30% in relation to upright standing; a polynomial of the second degree defines changes in IP as a function of back flexion for for both postures. There are differences in the pattern of changes in IP with a back flexion angle between sitting and standing postures, as back flexion in standing increases IP more than in sitting.

A noninvasive method to quantify the impairment of spinal motion ability in Parkinson's disease

PURPOSE

There is a high demand on spinal surgery in patients with Parkinson's disease (PD) but the results are sobering. Although detailed clinical and radiological diagnostics were carried out with great effort and expense, the biodynamic properties of the spine of PD patients have never been considered. We propose a noninvasive method to quantify the impairment of motion abilities in patients with PD.

METHODS

We present an analytical cross-sectional study of 21 patients with severe PD. All patients underwent a biodynamic assessment during a standardized movement-choreography. Thus, individual spinal motion profiles of each patient were objectively assessed and compared with a large comparative cohort of individuals without PD. Moreover, clinical scores to quantify motor function and lumbar back pain were collected and X-ray scans of the spine in standing position were taken and analysed.

RESULTS

Biodynamic measurement showed that 36.9% of the assessed motions of all PD patients were severely impaired. Men were generally more functionally impaired than women, in 52% of all motion parameters. The neurological and radiological diagnostics recorded pathological values, of which UPDRS-III ON correlated with findings of the biodynamics assessment (R = 0.52, p = 0.02).

CONCLUSIONS

The decision to operate on a PD patient's spine is far-reaching and requires careful consideration. Neurological and radiological scores did not correlate with the biodynamics of the spine. The resulting motion profile could be used as individual predictive factor to estimate whether patients are eligible for spinal surgery or alternative therapies.

Does Total Hip Arthroplasty Affect Spinopelvic and Spinal Alignment?: A Prospective Observational Investigation

STUDY DESIGN

A prospective observational study, level of evidence 3.

OBJECTIVES

The study with patients undergoing unilateral total hip arthroplasty (THA) aimed to evaluate the following hypotheses: (1) the spinal sagittal and coronal alignment alters due to THA, (2) the spinopelvic parameter changes after THA, (3) the spinopelvic alignment differs between sagittal balanced and imbalanced patients.

SUMMARY OF BACKGROUND DATA

Surgical correction of spinal sagittal misalignment affects the spinopelvic alignment and pelvic tilt. It is not yet known to what extent THA affects spinopelvic, spinal sagittal, and coronal alignment.

MATERIALS AND METHODS

A total of 153 patients undergoing THA were assessed with biplanar stereoradiography in standing position preoperatively and postoperatively. Two independent investigators examined C7-sagittal vertical axis (C7-SVA), pelvic incidence-lumbar lordosis (PI-LL) mismatch, lumbar lordosis (LL), C7-central sacral vertical line, pelvic oblique angle lumbosacral, intra-pelvic oblique angle, pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), anterior plane pelvic tilt (APPT), and pelvic femoral angle (PFA). An analysis of the sagittal misaligned subgroups of C7-SVA and PI-LL on the influence of the spinopelvic alignment was performed.

RESULTS

A significant difference in spinopelvic parameters was detected in the preoperative to postoperative comparison (SS, PT, APPT, and PFA; P <0.000) ( d =-0.394; d =0.609; d =-0.481; d =0.431). The coronal alignment and pelvic obliquity revealed no significant differences. The misaligned groups (C7-SVA; PI-LL) demonstrated significant increases in PI and PT and decreased in LL compared with the groups with normal sagittal alignment. Preoperatively, 66/153 (C7-SVA) and 46/153 (PI-LL) of the THA patients presented sagittal misalignment, respectively.

CONCLUSIONS

The results suggest an effect of THA on sagittal spinal and spinopelvic alignment, with a significant reduction of PT postoperatively and no effect on coronal alignment. Particularly striking are the significant differences in the misaligned groups, which may be classified as risk population and potentially can contribute biomechanically to a higher risk of posterior impingement and anterior THA dislocation. The substantial proportion of sagittal misaligned patients in the THA collective illustrates the crucial need for interdisciplinary collaboration.

Identifying relations between posture and pain in lower back pain patients: a narrative review

Posture is a “body’s attitude or the positioning of the limbs when standing or sitting.” There are many examples of different postures which include lordotic posture, swayback posture, flat back, and anterior pelvic tilt. Everyone in some of the other parts of their life considers pain as an unpleasant feeling or sensation that is experienced. Specifically, low back pain can be relentless and daunting to many people who often recovered without the need of a health care professional or any treatment by changing their posture or performing the movement. Various factors are leading to low back pain other than the postural fault, for instance, age, sedentary lifestyle, anxiety, and sleep. However, for back pain, posture has become deep-rooted in people’s thoughts. Health care professionals have instructed people to correct their posture to fight back pain. As people become older, the posture becomes worse, but this does not appear to cause pain. If any person cannot move his/her body, that does not mean that they are having a problem involving posture; that is actually because of a problem relating to movement. A study proved that there is no difference in the lordotic angle of the populace having an issue with LBP. There is a decrease in the range and speed of the movement performed. What matters is the movement rather than the appearance of standing or sitting. The primary aim of this paper is to improve knowledge and understanding of the association between posture and LBP, as, speaking about recent researches, they have observed no association between posture and LBP. There are many studies published to support this evidence. People call the importance of posture and alignment for while performing a heavy deadlift, land a jump, or any strenuous activity. Therefore, an urge to write a paper on this topic is to change the mindset of many people worrying out there about their postural faults or their appearances by providing information about varying their static posture to conform to some ideal and keep moving to improve their function.

Successful evaluation of spinal mobility measurements with the Epionics SPINE device in patients with axial spondyloarthritis compared to controls

OBJECTIVE

To evaluate ES for quantification of spinal mobility in patients with axSpA.

METHODS

A total of 153 individuals, 39 females and 114 males, were examined:134 axSpA patients, 40 non-(nr-) and 94 radiographic (r)-axSpA, and 19 healthy controls (HC), respectively. The results were compared using mean ES scores and modeling was performed using multivariable logistic regression models resulting in good validity and high discriminative power.

RESULTS

ES measurements showed meaningful differences between axSpA patients and HC (all p<0.001) as well as between r- and nr-axSpA (p<0.01). In axSpA patients a negative correlation between ES and BASMI values was found: -0.76≤r≤-0.52 (p<0.05). BASFI scores showed a similar trend (r > -0.39). Patients with r-axSpA had a more limited and slower spinal mobility than those with nr-axSpA. Other patient reported outcomes did almost not correlate.

CONCLUSION

This study shows that the ES is an objective performance measure and a valid tool to assess spinal mobility in axSpA, also based on OMERACT criteria. RoK and RoM scores provide additional information on physical function of axSpA patients.

Environmental physiotherapy and the case for multispecies justice in planetary health

Background:Global environmental change is fundamentally altering the composition and functioning of our planetary ecosystem. Effectively presenting the largest threat to the health of present and future generations, these changes and their health impacts are forcing us to think and practice healthcare in much broader terms than ever before. Objective:In this article, we provide an early outline for a radically otherwise, yet strangely familiar, environmental physiotherapy developed through a succession of carefully developed arguments. Discussion:We show how an underpinning belief in human exceptionalism has engendered an exploitative relationship with our natural planetary environment that has both shaped Western science and healthcare and led to our current environmental health crisis. Building on the dependence of human health on our planetary ecosystem, approaches like planetary health hold great promise for a corresponding, paradigmatic turn in healthcare. They fall short of this however, where they perpetuate anthropocentric interests and interventionist practices that have underpinned healthcare to date. Drawing on ethical and post-human philosophies we argue against human exceptionalism and for a solidarity that includes other-than-humans as the primary characteristic of planetary existence. Conclusion:Building on this foundation, we provide an early outline for a radically otherwise, yet strangely familiar, environmental physiotherapy, grounded in ecological awareness, multispecies justice, and a range of consonant practices of passivity and accompaniment, conceived as an alternative to the commonplace interventionism of healthcare.

Changes in physiotherapy students' beliefs and attitudes about low back pain through pre-registration training

BACKGROUND

Implementation of best-practice care for patients with low back pain (LBP) is an important issue. Physiotherapists' who hold unhelpful beliefs are less likely to adhere to guidelines and may negatively influence their patients' beliefs. Pre-registration education is critical in moving towards a biopsychosocial model of care. This study aimed to investigate the changes in 2nd year physiotherapy students' beliefs about LBP after a module on spinal pain management and determine whether these changes were maintained at the end of academic training.

METHODS

During three consecutive calendar years, this longitudinal cohort study assessed physiotherapy students' beliefs with the Back Pain Attitudes Questionnaires (Back-PAQ) in their 1st year, before and after their 2nd year spinal management learning module, and at the end of academic training (3rd year). Unpaired t-tests were conducted to explore changes in Back-PAQ score.

RESULTS

The mean response rate after the spinal management module was 90% (128/143 students). The mean (± SD) Back-PAQ score was 87.73 (± 14.21) before and 60.79 (± 11.44) after the module, representing a mean difference of - 26.95 (95%CI - 30.09 to - 23.80, p < 0.001). Beliefs were further improved at the end of 3rd year (- 7.16, 95%CI - 10.50 to - 3.81, p < 0.001).

CONCLUSIONS

A spinal management learning module considerably improved physiotherapy students' beliefs about back pain. Specifically, unhelpful beliefs about the back being vulnerable and in need of protection were substantially decreased after the module. Improvements were maintained at the end of academic training one-year later. Future research should investigate whether modifying students' beliefs leads to improved clinical practice in their first years of practice.

Measuring lumbar back motion during functional activities using a portable strain gauge sensor-based system: A comparative evaluation and reliability study

Quantifying lumbar back motion during functional activities in real-life environments may contribute to a better understanding of common pathologies such as spinal disorders. The current study therefore aimed at the comparative evaluation of the Epionics SPINE system, a portable device for measuring sagittal lumbar back motion during functional activities. Twenty healthy participants were therefore evaluated with the Epionics SPINE and a Vicon motion capture system in two identical separate research visits. They performed the following activities: standing, sitting, chair rising, box lifting, walking, running and a counter movement jump (CMJ). Lumbar lordosis angles were extracted as continuous values as well as average and range of motion (ROM) parameters. Agreement between the systems was evaluated using Bland-Altman analyses, whereas within- and between-session reliability were assessed using intraclass correlation coefficients (ICC) and minimal detectable changes (MDC). The analysis showed excellent agreement between the systems for chair rising, box lifting and CMJ with a systematic underestimation of lumbar lordosis angles during walking and running. Reliability was moderate to high for all continuous and discrete parameters (ICC ≥ 0.62), except for ROM during running (ICC = 0.29). MDC values were generally below 15°, except for CMJ (peak values up to 20° within and 25° between the sessions). The Epionics SPINE system performed similarly to a Vicon motion capture system for measuring lumbar lordosis angles during functional activities and showed high consistency within and between measurement sessions. These findings can serve researchers and clinicians as a bench mark for future investigations using the system in populations with spinal pathologies.

How reproducible do we stand and sit? Indications for a reliable sagittal spinal assessment

BACKGROUND

Currently, an upright standing posture is normally adopted for evaluations of spinal alignment, which is however sensitive to posture variations. Thus, finding a reproducible reference is essential. This study aimed to evaluate the reproducibility of standing and sitting postures at different arm positions in five consecutive repetitions.

METHODS

22 asymptomatic subjects (11 males; 11 females) aged 20-35 years were included. Subjects were repeatedly asked to adopt different arm positions in standing and sitting. The absolute reposition errors of lumbar lordosis and sacral orientation between two consecutive repetitions were assessed with a non-radiological back measurement system.

FINDINGS

During standing at the relaxed arm position, the median absolute reposition errors of lumbar lordosis and sacral orientation were 1.14° (range 0.23°-3.80°) and 0.92° (range 0.17°-3.27°), respectively, which increased to 1.75° (range 0.21-4.97°) and 1.36° (range 0.35°-4.08°) during sitting (P < 0.01). The absolute reposition error of lumbar lordosis was non-significantly lower at the relaxed and clasped arm positions than at other arm positions. Between the first two repetitions, the absolute reposition errors of both, lumbar lordosis and sacral orientation, were greater than between the remaining two consecutive repetitions (P < 0.01). Both during standing and sitting, lumbar lordosis was smallest when hands holding two bars (P < 0.05).

INTERPRETATION

Sitting showed a worse reproducibility than standing. When assessing sagittal spinal balance, the clasped arm position during standing is recommended and an initial trial can help to reduce inception irreproducibility.

[Epionics SPINE-use of an objective method to examine spinal mobility in patients with axial spondyloarthritis]

Axial spondylarthritis (axSpA) is a chronic inflammatory disease of the spine that can be associated with loss of physical function, mobility and upright postural impairment. Established tools for the assessment of function that are largely based on subjective perception are semiquantitatively recorded by standardized questionnaires (Bath ankylosing spondylitis functional index, BASFI), while measurement of spinal mobility of patients with axSpA is based on physical examination of various movement regions particularly the axial skeleton (Bath ankylosing spondylitis metrology index, BASMI). Recently, a performance test has been added to assess the range of motion and speed of certain tasks (AS performance-based improved test, ASPI); however, since these tests have limited reliability and reproducibility, more objective tests would be desirable. In this study the spinal mobility of patients with axSpA was quantified using the Epionics SPINE device (ES) and data were evaluated using the outcome measures in rheumatology (OMERACT) criteria. The ES automatically measures various patterns of spinal movements using electronic sensors, which also assess the range and speed of carrying out movements. Patients with back pain from other causes and persons without back pain served as controls. The measurement results obtained with ES differed between the groups and correlated with BASMI values (r = 0.53-0.82, all p = <0.03). Patients with radiographically detectable axSpA had more limited and slower mobility than those with non-radiographically detectable axSpA. Overall, the results presented here suggest that ES measurements represent a valid and objective measurement procedure of spinal mobility for axSpA patients.

Spinal Deformity Surgery: A Critical Review of Alignment and Balance

Correction of the overall coronal and/or sagittal plane deformities is one of the main predictors of successful spinal surgery. In routine clinical practice, spinal alignment is assessed using several spinal and pelvic parameters, such as pelvic incidence and tilt, sacral slope, lumbar lordosis, thoracic kyphosis, and sagittal vertical axis. Standard values have been defined for all these parameters, and the formulas of correction have been set for determining the surgical strategy. However, several factors can potentially bias these formulas. First, all standard values are measured using conventional plain radiographs and are, therefore, prone to bias. The radiologist, measuring surgeon, and patient are possible confounding influencing factors. Second, spino-pelvic compensatory effects and biomechanically relevant structures for the patient’s posture, including ligaments, tendons, and muscles, have received minimal consideration in the literature. Therefore, even in cases of appropriately planned deformity correction surgeries, complications, revision rates, and surgical outcomes significantly vary. This study aimed to illustrate the current clinical weaknesses of the assessment of spinal alignment and the importance of holistically approaching the musculoskeletal system for any spinal deformity surgery. We believe that our detailed insights regarding spinal, sagittal, and coronal alignments as well as the considerations of an individual’s spinal balance will contribute toward improvement in routine patient care.