Manual Forces Applied During Posterior-to-Anterior Spinal Mobilization: A Review of the Evidence

Defining and measuring objective and subjective spinal stiffness: a scoping review

PURPOSE

Examine and identify the breadth of definitions and measures of objective and subjective spinal stiffness in the literature, with a focus on clinical implications.

METHODS

A scoping review was conducted to determine what is known about definitions and measures of the specific term of spinal stiffness. Following the framework by Arksey and O'Malley, eligible peer-reviewed studies identified using PubMed, Ebsco health, and Scopus were included if they reported definitions or measures of spinal stiffness. Using a data abstraction form, the studies were classified into four themes: biomechanical, surgical, pathophysiological, and segmental spinal assessment. To identify similarities and differences between studies, sixteen categories were generated.

RESULTS

In total, 2426 records were identified, and 410 met the eligibility criteria. There were 350 measures (132 subjective; 218 objective measures) and 93 indicators of spinal stiffness. The majority of studies (n = 69%) did not define stiffness.

CONCLUSION

This review highlights the breadth of objective and subjective measures that are both clinically and methodologically diverse. There is no consensus regarding a standardised definition of stiffness in the reviewed literature.

Spinal mobilization force-time characteristics: A scoping literature review

BACKGROUND

Spinal mobilization (SMob) is often included in the conservative management of spinal pain conditions as a recommended and effective treatment. While some studies quantify the biomechanical (kinetic) parameters of SMob, interpretation of findings is difficult due to poor reporting of methodological details. The aim of this study was to synthesise the literature describing force-time characteristics of manually applied SMob.

METHODS

This study is reported in accordance with the Preferred Reporting Items for Scoping Reviews (PRISMA-ScR) statement. Databases were searched from inception to October 2022: MEDLINE (Ovid), Embase, CINAHL, ICL, PEDro and Cochrane Library. Data were extracted and reported descriptively for the following domains: general study characteristics, number of and characteristics of individuals who delivered/received SMob, region treated, equipment used and force-time characteristics of SMob.

RESULTS

There were 7,607 records identified and of these, 36 (0.5%) were included in the analysis. SMob was delivered to the cervical spine in 13 (36.1%), the thoracic spine in 3 (8.3%) and the lumbopelvic spine in 18 (50.0%) studies. In 2 (5.6%) studies, spinal region was not specified. For SMob applied to all spinal regions, force-time characteristics were: peak force (0-128N); duration (10-120s); frequency (0.1-4.5Hz); and force amplitude (1-102N).

CONCLUSIONS

This study reports considerable variability of the force-time characteristics of SMob. In studies reporting force-time characteristics, SMob was most frequently delivered to the lumbar and cervical spine of humans and most commonly peak force was reported. Future studies should focus on the detailed reporting of force-time characteristics to facilitate the investigation of clinical dose-response effects.

Harnessing joint distraction for the treatment of osteoarthritis: a bibliometric and visualized analysis

Osteoarthritis (OA) stands as a prevalent degenerative joint ailment, demanding immediate attention towards the development of efficacious therapeutic interventions. Presently, a definitive cure for OA remains elusive, and when conservative treatment modalities prove ineffective, resorting to a joint prosthesis becomes imperative. Temporary distraction emerges as a pivotal joint-preserving intervention in human OA patients, conferring both clinical amelioration and structural enhancements. Although extant clinical investigations exist, they are characterized by relatively modest sample sizes. Nonetheless, these studies furnish compelling evidence affirming that joint distraction engenders sustained clinical amelioration and structural refinement. Despite substantial strides in the last decade, a bibliometric analysis of joint distraction within the realm of osteoarthritis treatment research has been conspicuously absent. In this context, we have undertaken a comparative investigation utilizing bibliometric methodologies to scrutinize the landscape of joint distraction within osteoarthritis treatment. Our comprehensive analysis encompassed 469 scholarly articles. Our findings evince a consistent escalation in global research interest and publication output pertaining to this subject. The United States emerged as the frontrunner in international collaboration, publication count, and citation frequency, underscoring its preeminence in this domain. The journal "Osteoarthritis and Cartilage" emerged as the principal platform for disseminating research output on this subject. Notably, Mastbergen SC emerged as the most prolific contributor in terms of authorship. The identified keywords predominantly revolved around non-surgical interventions and joint arthroscopy procedures. This bibliometric analysis, augmented by visual representations, furnishes invaluable insights into the evolutionary trajectory of joint distraction as an osteoarthritis treatment modality spanning from 2003 to 2023. These insights will serve as a compass for the scientific community, facilitating further exploration in this promising domain.

The immediate effect of unilaterally applied lumbar mobilisations on the passive straight leg raise and ninety-ninety test in asymptomatic adults: A randomised crossover trial

OBJECTIVES

This study assessed the immediate effect of unilateral posterior-anterior lumbar mobilisations on trunk and lower limb flexibility in asymptomatic individuals.

STUDY DESIGN

Randomised cross-over trial.

PARTICIPANTS

Twenty-seven participants (age = 26.0 years ±6.4) with no current or recent history of lower back or leg pain/surgery completed the study.

MAIN OUTCOME MEASURES

Participants attended two sessions, receiving either grade 3 ('treatment') or grade 1 ('sham') unilateral spinal mobilisations. Outcome measures (modified-modified Schober's test [MMST], ninety-ninety test [NNT], and passive straight-leg raise [PSLR]) were assessed immediately before and after (post-1 and post-2) the intervention. An instrumented hand-held dynamometer was used to measure the change in NNT and PSLR joint angle (deg) and passive stiffness (Nm/deg) pre- and post-intervention.

RESULTS

The mean change in PSLR angle at the first (P1) and maximal (P2) point of discomfort following the treatment was 4.8° and 5.5°, and 5.6° and 5.7°, larger than the sham at post-1 and post-2, respectively. There was no effect of the treatment on the PSLR at P1 or P2 for the contralateral limb at either timepoint. There was no effect of the treatment on MMST distance, NNT angle or passive stiffness, or PSLR passive stiffness, for either limb.

CONCLUSIONS

Immediate effects of unilateral posterior-anterior lumbar mobilisations in asymptomatic individuals are isolated to treatment side and limited to a small increase in PSLR range, with no change in lumbar motion or the NNT test.

Effectiveness of manual therapy, computerised mobilisation plus home exercise, and home exercise only in treating work-related neck pain: study protocol for a randomised controlled trial

BACKGROUND

Work-related neck pain (WRNP) is a leading cause of disability and absenteeism. Patients with neck pain often have neck muscle tenderness and decreased cervical mobility, which are sometimes combined with psychosocial issues, such as pain catastrophising, thereby reducing their work ability. Whilst multidisciplinary treatments, including pharmacological interventions, manual therapy and specific neck exercises, have produced positive outcomes, effective personalised treatment modalities are still needed. Furthermore, manual therapies using the hands can bring fatigue to therapist. Occiflex is a computerised device that can provide personalised segmental joint mobilisation based on symptoms and injury of the patient and then provide a medium range of joint activities to improve range of cervical motion. This study aims to compare the effect of computerised mobilisation performed with Occiflex with that of traditional manual therapy on WRNP.

METHODS

We will conduct a prospective randomised controlled trial including 150 patients with WRNP. These patients will be randomly assigned to one of three groups: (i) home exercise (TE), (ii) home exercise plus Occiflex therapy and (iii) home exercise plus manual therapy delivered by a physical therapist. Ten treatment sessions will be performed in four weeks. During the trial, these patients will receive only the assigned treatment and the standard patient education and will be asked not to use any analgesics unless strictly necessary. Assessments by trained evaluators will occur at baseline, week 4 and week 12. The primary outcome measures will include visual analogue scale (VAS) for pain and neck disability index (NDI) at each time point. Secondary outcome measures will include cervical range of motion (CROM), pressure pain threshold (PPT), global perceived effect (GPE) and sick leave. Group by time differences will be analysed using linear mixed models with repeated measures.

DISCUSSION

This protocol describes the methods for a randomised controlled trial to compare the effectiveness of computerised versus manual mobilisation techniques in treating WRNP. The results will provide an alternative method (Occiflex) that is possibly effective for treating neck pain whilst minimising the manual work done by therapists.

TRIAL REGISTRATION

The study protocol was retrospectively registered at http://www.chictr.org.cn (registration number: ChiCTR2100053076) on November 10, 2021.

Neuromechanical Responses to Spinal Manipulation and Mobilization: A Crossover Randomized Clinical Trial

OBJECTIVE

The purpose of this study was to compare the immediate effect of spinal manipulation (SMa) and spinal mobilization (SMo) on muscular responses, spinal stiffness, and segmental spinal pressure evoked pain in a population of participants with chronic middle back pain (MBP).

METHODS

In a crossover randomized trial, 2 experienced chiropractors assessed whether volunteers were eligible for the protocol according to a list of specific inclusion and exclusion criteria. Individuals with MBP participated in 2 experimental sessions within 72 hours. During the first session, participants randomly received a SMa or SMo delivered by an apparatus using a servolinear motor. During the second session, the other modality was delivered. Spinal stiffness and pressure-provoked pain intensity outcomes were assessed before and after each therapy, and muscular responses were recorded during the treatment using surface electromyographic sensors. Signed-rank Wilcoxon tests for muscular responses and generalized model for repeated measure for spinal stiffness and pressure-provoked pain were used for statistical analyses.

RESULTS

Among the 32 potential participants, 26 (mean age 29.9 [±9.14], 15 women) completed both sessions. Between-group differences were observed for the muscular response amplitude (P < .001), and indeed the normalized RMS muscular response was found to be higher during SMa than SMo. Similar results were observed for pressure-provoked pain intensity at the level of therapeutic modality application (P = .002) as a higher decrease in pain was found after SMa (47.9 [±22.8] to 36.6 [±23.7]) compared with SMo (47.2 [±23.2] to 45.5 [±24.3]). No between-group differences were found for spinal stiffness change, nor for terminal (P = .08) and global spinal stiffness (P = .06).

CONCLUSION

In a controlled environment, spinal manipulation and mobilization generated different muscle responses and had different immediate effects on pressure-provoked pain intensity for subjects with MBP.

Dosage of joint mobilisation for the management of rotator cuff-related shoulder pain: protocol for a scoping review

INTRODUCTION

Rotator cuff-related shoulder pain is the most common diagnosis of shoulder pain, which ranks as the third most common musculoskeletal disorder. The first-line treatment for patients with rotator cuff-related shoulder pain is physiotherapy, and joint mobilisation is widely used in conjunction with other modalities. The type and dosage of joint mobilisations could influence treatment outcomes for patients with rotator cuff-related shoulder pain, although research evidence is inconclusive.

OBJECTIVES

To (1) systematically search, identify and map the reported type and dosage of joint mobilisations used in previous studies for the management of patients with rotator cuff-related shoulder pain; and (2) summarise the rationale for adopting a specific joint mobilisation dosage.

METHODS AND ANALYSIS

We will follow the methodological framework outlined by Arksey and O'Malley and report the results as per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guideline. Two authors will independently screen and extract data from the six databases: PubMed, Scopus, Web of Science, CINAHL, Cochrane Library and SPORTDiscus, with publication date from their inceptions to 25 August 2021. A third author will be consulted if the two authors disagree about the inclusion of any study in the review. We will summarise the results using descriptive statistics and qualitative thematic analysis.

ETHICS AND DISSEMINATION

Ethical approval is not required for this protocol. Mapping and summarising the reported type and dosage of joint mobilisations for patients with rotator cuff-related shoulder pain from previous studies will provide a foundation for further optimal selection of type and dosage of joint mobilisations for treating patients with rotator cuff-related shoulder pain. The review is part of an ongoing research that focuses on joint mobilisation for patients with rotator cuff-related shoulder pain. The results will be disseminated through presentations at academic conferences and a peer-reviewed publication.

The Immediate Effect of Adding Lumbar Mobilization to A Static Stretching Program on Hamstrings Range of Motion: An Exploratory Study

A contributing risk factor and a byproduct of a hamstrings strain is limited hamstrings range of motion (ROM). Some evidence supports static stretching (SS) and lumbar spinal mobilization therapy (LSMT) as an effective means for increasing hamstrings ROM. However, the efficacy of combining LSMT and SS for increasing hamstrings ROM is unknown. The objective of the study is to quantify the immediate effects of the combination of LSMT and SS compared to LSMT and SS on hamstrings ROM in a healthy population. Thirty participants were randomized by block allocation into one of three intervention groups: (1) LSMT (unilateral lumbar PA mobilization at L-4); (2) SS; or (3) combination of LSMT and SS. Hamstrings ROM was measured pre- and post-intervention by the active knee extension test (AKET). There was no group-by-time interaction effect (p = 0.871). Within group analysis revealed a significant statistical change and a large effect size: LSMT (p = .037, RCI = 3.36, d = 0.771); SS (p = 0.035, RCI = 2.94, d = 0.781); combination (p = .005, RCI = 4.21, d = 1.186. The findings suggest that the combination of LSMT and SS does not have a further effect on hamstrings ROM compared to the individual results of LSMT or SS.

Devices Used to Measure Force-Time Characteristics of Spinal Manipulations and Mobilizations: A Mixed-Methods Scoping Review on Metrologic Properties and Factors Influencing Use

Background: Spinal manipulations (SMT) and mobilizations (MOB) are interventions commonly performed by many health care providers to manage musculoskeletal conditions. The clinical effects of these interventions are believed to be, at least in part, associated with their force-time characteristics. Numerous devices have been developed to measure the force-time characteristics of these modalities. The use of a device may be facilitated or limited by different factors such as its metrologic properties.

Objectives: This mixed-method scoping review aimed to characterize the metrologic properties of devices used to measure SMT/MOB force-time characteristics and to determine which factors may facilitate or limit the use of such devices within the context of research, education and clinical practice.

Methods: This study followed the Joanna Briggs Institute's framework. The literature search strategy included four concepts: (1) devices, (2) measurement of SMT or MOB force-time characteristics on humans, (3) factors facilitating or limiting the use of devices, and (4) metrologic properties. Two reviewers independently reviewed titles, abstracts and full articles to determine inclusion. To be included, studies had to report on a device metrologic property (e.g., reliability, accuracy) and/or discuss factors that may facilitate or limit the use of the device within the context of research, education or clinical practice. Metrologic properties were extracted per device. Limiting and facilitating factors were extracted and themes were identified.

Results: From the 8,998 studies initially retrieved, 46 studies were finally included. Ten devices measuring SMT/MOB force-time characteristics at the clinician-patient interface and six measuring them at patient-table interfaces were identified. Between zero and eight metrologic properties were reported per device: measurement error (defined as validity, accuracy, fidelity, or calibration), reliability/repeatability, coupling/crosstalk effect, linearity/correlation, sensitivity, variability, drift, and calibration. From the results, five themes related to the facilitating and limiting factors were developed: user-friendliness and versatility, metrologic/intrinsic properties, cost and durability, technique application, and feedback.

Conclusion: Various devices are available to measure SMT/MOB force-time characteristics. Metrologic properties were reported for most devices, but terminology standardization is lacking. The usefulness of a device in a particular context should be determined considering the metrologic properties as well as other potential facilitating and limiting factors.

Objective measurement of Inferior-Directed stiffness in glenohumeral joint using a specially designed robotic device in healthy shoulders; Within- and Between-Session reliability

Clinical assessment of capsuloligamentous structures of the glenohumeral joint has been qualitative and subjective in nature, as demonstrated by limited intra- and inter-rater reliability. Robotic devices were utilized to develop a clinically objective measurement technique for glenohumeral joint stiffness. The purpose of this study was to quantify the amount of inferior-direction stiffness of the glenohumeral joint using a safe clinical device in the asymptomatic individuals, and to determine between trial and between session reliability of the robotic device. Twenty healthy subjects were recruited via convenience sampling. Inferior-directed translation and applying force were measured using displacement and force sensors of a robotic device. The stiffness values were calculated as the mean of the slopes of the linear portions of the force-displacement curves for the cycles obtained after familiarization and preconditioning. Four trials for each measurement occasion were averaged to determine the stiffness value for each subject in one session. Repeatability of glenohumeral joint stiffness measurements for between trials and between two sessions was determined using intraclass correlation values and standard error of the measurements. The mean stiffness value was 1.50 N/mm (±0.40) and 1.52 N/mm (±0.40), respectively. The robotic device for stiffness assessment was reliable for repeated measures of stiffness in one session, and between sessions with ICC equal 0.96 (95% CI 0.93-0.98), and 0.97 (95% CI 0.95-0.99), respectively. The SEM between the trials was in each session 0.08 N/mm. The results of this study provide that our robotic technique for quantifying glenohumeral joint stiffness is precise and reproducible.

Characterization of thoracic spinal manipulation and mobilization forces in older adults

BACKGROUND

Spinal mobilization and spinal manipulation are common interventions used by manual therapists to treat musculoskeletal conditions in older adults. Their force-time characteristics applied to older adults' thoracic spine are important considerations for effectiveness and safety but remain unknown. This study aimed to describe the force-time characteristics of posterior-to-anterior spinal mobilization and manipulation delivered to older adults' thoracic spine.

METHODS

Twenty-one older adults (≥65 years) with no thoracic pain received posterior-to-anterior thoracic spinal mobilization and/or manipulation with the force characteristics a chiropractor deemed appropriate. Six-degree-of-freedom load cells and an instrumented treatment table recorded the force characteristics of both interventions at the clinician-participant and participant-table interfaces, respectively. Preload force, total peak force, time to peak and loading rate were analyzed descriptively.

FINDINGS

Based on data from 18 adults (56% female; average: 70 years old), mean resultant spinal mobilization forces at the clinician-participant interface were: 220 ± 51 N during preload, 323 ± 67 N total peak force, and 312 ± 38 ms time to peak. At the participant-table interface, mobilization forces were 201 ± 50 N during preload, 296 ± 63 N total peak force, and 308 ± 44 ms time to peak. Mean resultant spinal manipulation forces at the clinician-participant interface were: 260 ± 41 N during preload, 470 ± 46 N total peak force, and 165 ± 28 ms time to peak. At the participant table interface, spinal manipulation forces were 236 ± 47 N during preload, 463 ± 57 N total peak force, and 169 ± 28 ms time to peak.

INTERPRETATION

Results suggest older adults experience unique, but comparable force-time characteristics during spinal mobilization and manipulation delivered to their thoracic spine compared to the ones delivered to younger adults described in the literature.

Posterior to anterior spinal stiffness measured in a sample of 127 secondary care low back pain patients

BACKGROUND

The sensation of spinal stiffness is a commonly reported symptom among back pain patients, with the clinical assessment of spinal stiffness usually being part of the decision-making process when deciding on providing manual treatment of low back pain. While any relationship between spinal stiffness and low back pain is likely to be multifactorial, prior exploration of this relationship has been overly simplistic (e.g., univariate regression analyses). The purpose of this study was to address this gap by taking a broader approach to compare instrumented measures of spinal stiffness to demographic characteristics, pain phenotypes, psychometrics, and spine-related disability in a sample of secondary care low back pain patients using multivariate regression analysis.

METHODS

Instrumented spinal stiffness measures from 127 patients in secondary care were used to calculate terminal and global spinal stiffness scores. A best subset analysis was used to find the subsets of 14 independent variables that most accurately predicted stiffness based on the evaluation of the adjusted R-square, Akaike Information Criteria, and the Bayesian Information Criteria.

FINDINGS

In the resulting multivariate models, sex (p < 0.001) and age (p < 0.001) were the primary determinants of terminal stiffness, while global stiffness was primarily determined by age (p = 0.003) and disability (p = 0.024).

INTERPRETATION

Instrumented measures of spinal stiffness are multifactorial in nature, and future research into this area should make use of multivariate analyses.

The profile of older adults seeking chiropractic care: a secondary analysis

BACKGROUND

Musculoskeletal conditions are the primary reason older adults seek general medical care, resulting in older adults as the highest consumers of health care services. While there is high use of chiropractic care by older adults, there is no recent, specific data on why older adults seek chiropractic care and how chiropractors manage conditions. Therefore, the purpose of this study was to describe the demographic characteristics of older adults seeking chiropractic care, and to report problems diagnosed by chiropractors and the treatment provided to older adults who seek chiropractic care.

METHODS

A secondary data analysis from two, large cross-sectional observational studies conducted in Australia (COAST) and Canada (O-COAST). Patient encounter and diagnoses were classified using the International Classification of Primary Care, 2nd edition (ICPC-2), using the Australian ICPC-2 PLUS general practice terminology and the ICPC-2 PLUS Chiro terminology. Descriptive statistics were used to summarize chiropractor, patient and encounter characteristics. Encounter and patient characteristics were compared between younger (< 65 years old) and older (≥65 years old) adults using χ² tests or t-tests, accounting for the clustering of patients and encounters within chiropractors.

RESULTS

A total of 6781 chiropractor-adult patient encounters were recorded. Of these, 1067 encounters were for persons aged > 65 years (16%), from 897 unique older patients. The most common diagnosis within older adult encounters was a back problem (56%), followed by neck problems (10%). Soft tissue techniques were most frequently used for older patients (85 in every 100 encounters) and in 29 of every 100 encounters, chiropractors recommended exercise to older patients as a part of their treatment.

CONCLUSIONS

From 6781 chiropractor-adult patient encounters across two countries, one in seven adult chiropractic patients were > 65 years. Of these, nearly 60% presented with a back problem, with neck pain and lower limb problems the next most common presentation to chiropractors. Musculoskeletal conditions have a significant burden in terms of disability in older adults and are the most commonly treated conditions in chiropractic practice. Future research should explore the clinical course of back pain in older patients seeking chiropractic care and compare the provision of care to older adults across healthcare professions.

New real-time force monitoring device with enhanced accuracy for evaluation of applied force during the joint mobilization technique

BACKGROUND

Force Monitoring Devices (FMDs) reported in the literature to monitor applied force during Joint Mobilization Technique (JMT) possess complex design/bulky which alters the execution of treatment, has poor accuracy and is unable to feel the resistance provided by soft tissues limits its usage in the clinical settings.

OBJECTIVES

This study aims to develop a highly accurate, portable FMD and to demonstrate real-time monitoring of force applied by health professionals during JMT without altering its execution.

METHODS

The FMD was constructed using the FlexiForce sensor, potential divider, ATmega 328 microcontroller, custom-written software, and liquid crystal display. The calibration, accuracy, and cyclic repeatability of the FMD were tested from 0 to 90 N applied load with a gold standard universal testing machine. For practical demonstration, the FMD was tested for monitoring applied force by a physiotherapist while performing Maitland's grade I to IV over the 6th cervical vertebra among 30 healthy subjects.

RESULTS

The obtained Bland-Altman plot limits agreement for accuracy, and cyclic repeatability was -1.57 N to 1.22 N, and -1.26 N to 1.26 N, respectively with standard deviation and standard error of the mean values of 3.77% and 0.73% and 2.15% and 0.23%, respectively. The test-retest reliability of the FMD tested by the same researcher at an interval of one week showed an excellent intra-class correlation coefficient of r= 1.00. The obtained force readings for grade I to IV among 30 subjects ranged from 10.33 N to 45.24 N.

CONCLUSIONS

Appreciable performance of the developed FMD suggested that it may be useful to monitor force applied by clinicians during JMT among neck pain subjects and is a useful educational tool for academicians to teach mobilization skills.

Reliability and accuracy of an expert physical therapist as a reference standard for a manual therapy joint mobilization trial

Objective: Previous studies on learning joint mobilization techniques have used expert practitioners as the reference standard as there is no current evidence on what ideal forces would be for effective mobilizations. However, none of these trials have documented the reliability or accuracy of the reference standard. Therefore, the purpose of this study was to report both the reliability and accuracy of an expert physical therapist (PT) acting as a reference standard for a manual therapy joint mobilization trial.Methods: A secondary analysis was performed using data from a published randomized, controlled, crossover study. The mobilization technique studied was the central posterior to anterior (PA) joint mobilization of the L3 vertebra. Reliability and accuracy data for the reference standard were collected over four time periods spanning 16 weeks.Results: Intrarater reliability of the expert PT for R1 and R2 joint forces was excellent (R1 Force ICC_3,3 0.95, 95%CI 0.76-0.99 and R2 Force ICC_3,3 0.90, 95%CI 0.49-0.99). Additionally, the expert PT was 92.3% accurate (mean % error±SD, 7.7 ± 5.5) when finding Grade III mean peak mobilization force and 85.1% accurate (mean % error±SD, 14.9 ± 8.3) when finding Grade IV mean peak mobilization force. Finally, correlations between actual applied forces and computed ideal forces were excellent (Pearson r 0.79-0.92, n = 24, P < 0.01 for all correlations).Discussion: The expert PT in this manual therapy joint mobilization trial showed excellent reliability and accuracy as the reference standard. The study supports the use of implementing quantitative feedback devices into the teaching of joint mobilization when a reliable and accurate reference standard has been identified.Level of Evidence: 2b.

Assessing forces during spinal manipulation and mobilization: factors influencing the difference between forces at the patient-table and clinician-patient interfaces

Background

Spinal manipulative therapy (SMT) and mobilization (MOB) effects are believed to be related to their force characteristics. Most previous studies have either measured the force at the patient-table interface or at the clinician-patient interface. The objectives of this study were to determine 1) the difference between the force measured at the patient-table interface and the force applied at the clinician-patient interface during thoracic SMT and MOB, and 2) the influence of the SMT/MOB characteristics, participants’ anthropometry and muscle activity (sEMG) on this difference.

Methods

An apparatus using a servo-linear motor executed 8 SMT/MOB at the T7 vertebrae in 34 healthy adults between May and June 2019. SMT and MOB were characterized by a 20 N preload, total peak forces of 100 N or 200 N, and thrust durations of 100 ms, 250 ms, 1 s or 2 s. During each trial, thoracic sEMG, apparatus displacement as well as forces at the patient-table interface and the clinician-patient interface were recorded. The difference between the force at both interfaces was calculated. The effect of SMT/MOB characteristics on the difference between forces at both interfaces and correlations between this difference and potential influencing factors were evaluated.

Results

Force magnitudes at the patient-table interface were, in most trials, greater than the force at the clinician-patient interface (up to 135 N). SMT/MOB characteristics (total peak force, thrust duration and rate of force application) affected the difference between forces at both interfaces (all p-values< 0.05). No factor showed significant correlations with the difference between forces at both interfaces for the 8 SMT/MOB.

Conclusions

The results revealed that the force measured at the patient-table interface is greater than the applied force at the clinician-patient interface during thoracic SMT and MOB. By which mechanism the force is amplified is not yet fully understood.

Investigation of reaction force magnitude and orientation during supine thoracic thrust manipulation applied to intervertebral and costovertebral regions

BACKGROUND

Spinal manipulative techniques are commonly used in manual therapies but quantified descriptive and reliability data are lacking considering supine thoracic thrust manipulation.

OBJECTIVES

The purpose of this study is to explore and compare kinetic parameters during supine thoracic thrust manipulation performed at two different thoracic regions. Intra-rater task repeatability and influence of practitioners were estimated.

DESIGN

Exploratory and agreement study.

METHODS

Kinetic parameters were assessed by examining reaction force magnitude and orientation (on the basis of the zenithal angle) using force platforms. Manipulative procedure (consisting in the application of 3 preloads followed by one thrust adjustment) at both intervertebral and costovertebral region was performed by different practitioners at three sessions. Application of thrust was allowed for experienced practitioners only. Preload force, peak force magnitude and vector force orientation were compared between anatomical sites, sessions and practitioners, and bias with limit of agreement were estimated.

RESULTS

Repeatability analysis showed that practitioners achieved similar preload and peak force independent of the session, with comparable force orientation. Differences between practitioners were observed for preload and peak force but not regarding the zenithal angle during the thrust phase.

CONCLUSIONS

The present study is the first that explores kinetic parameters for supine thoracic thrust manipulation applied on two different regions of the thorax. Results confirm consistency of performance among practitioners for supine manipulative techniques at intervertebral and costovertebral region. While task repeatability was confirmed, several differences were observed between practitioners. Further investigations would examine velocity, acceleration and potential neurophysiological effect of such manipulative technique.

The Biomechanical Analysis of Magnitude and Direction of Force by Different Techniques of Thoracic Spinal Manipulation

BACKGROUND

Spinal manipulation (SM) has been widely recognized and used with success in health care fields for spinal joint dysfunction and pain. SM is a procedure that involves small amplitude manipulative thrusts performed with speed. These forces are complex three-dimensional (3-D) forces delivered to create forces and moments at the joint of interest to cause joint movements. The aim of this study was to conduct a 3-dimensional analysis of the magnitude and direction of the forces transmitted in 2 techniques of thoracic spinal manipulation (TSM). Materials/Methods. Thirty-two healthy participants were recruited from the university community. The physical therapist performed TSM using anterior (A) to posterior (P) and P to A techniques once at each of T3, T7, and T12 spinal levels. The magnitude and direction of the forces transmitted during TSM were sensed by the force plates, and the camera system monitored vertebral motion by tracking motion markers.

RESULTS

There were no significant differences on the x-axis while there were significant differences on the y-axis between the measured spinal levels in the P to A technique. There were significant differences found at preload force maximum, preload force minimum, and peak force between T3 and T12 and between T7 and T12 and at peak base force between T7 and T12 on the z-axis. In the A to P technique, there were significant differences in the change of force in measured spinal levels at different axes.

CONCLUSION

These study findings can help therapists better understand the mechanism of TSM and enhance the clinical usefulness of TSM.

Reaction Force Magnitude and Orientation During Supine Thoracic Spine Thrust Manipulation: An Exploratory Analysis and Reliability of Preload and Impulse Phase

OBJECTIVE

The main purpose of this study was to explore specific kinetic parameters during supine thoracic thrust manipulation and to analyze task reliability and differences between various practitioners METHODS: Kinetic parameters were assessed by examining ground reaction force magnitude and orientation (on the basis of the zenithal angle) using force platforms. The manipulative procedure (consisting of the application of 3 preloads followed by 1 single thrust adjustment) was performed by different practitioners at 3 sessions. Application of thrust was allowed for trained practitioners only. Preload force, peak force, and vector force orientation were compared between sessions and practitioners.

RESULTS

Reliability analysis showed that practitioners achieved similar preload and peak force independent of the session, with comparable force orientation data. Differences between practitioners were observed for preload and peak force but not regarding the zenithal angle during the thrust phase.

CONCLUSION

This study is the first that explores kinetic parameters for supine thoracic thrust manipulation. Task repeatability was confirmed and several differences were observed between practitioners. Certainly, there is a need for further investigation examining both dynamic parameters (ie, velocity and accelerations) and the potential neurologic effect of such manipulative technique.

Quantifying Lumbar Mobilization With Inertial Measurement Unit

OBJECTIVE

Lumbar mobilization is a standard intervention for the management of low back pain, yet ways to quantify lumbar mobilization are limited. An inertial measurement unit (IMU) is a small and inexpensive device that can be used to quantify lumbar mobilization. The objective of this study was to determine the validity and reliability of an IMU in measuring the amplitude of displacement of a clinician's hand movement during oscillatory lumbar mobilization.

METHODS

An IMU was secured on a clinician's hand during application of mobilization forces at the L4 segment of 16 healthy participants. The validity of the IMU was tested against common laboratory methods of measurements (force plate and motion capture system). The reliability of the IMU measurements was determined between 2 clinicians (inter-rater reliability) and between 2 sessions (intra-rater reliability) by calculating percent error of measurement (%e) and limits of agreement (LOA). The reliability was considered high when |%e| ≤ 10% and |LOA| ≤ 20%; moderate when |%e| 10% to 20% and |LOA| 21% to 40%; and non-acceptable when |%e| > 20% and |LOA| > 40%.

RESULTS

The IMU measurements had high correlation with the force plate measurements (r_s = 0.94) and high agreement with the motion capture system measurements (%e = 4%, LOA = -11% and 20%). Both the inter-rater reliability (%e = 6%, LOA = -25% and 37%) and the intrarater reliability (%e = -1%, LOA = -29% and 27%) of IMU measurements were moderate.

CONCLUSION

The IMU seems to be a valid device to measure the amplitude of a clinician's hand movement. The moderate reliability found in this study may not reflect poor reliability of the IMU as much as inconsistency in reapplication of lumbar mobilization.

Completeness of the description of manipulation and mobilisation techniques in randomized controlled trials in neck pain; A review using the TiDieR checklist

STUDY DESIGN

A secondary analysis of a systematic review.

BACKGROUND

Manipulations or mobilizations are commonly used interventions in patients with mechanical neck pain. The treatment effects have often been studied in randomized controlled trials (RCT) which are generally considered the gold standard in evaluating the treatment effects, mainly due to its high internal validity. External validity is defined as the extent to which the effects can be generalised to clinical practice. An important prerequisite for this is that interventions used in clinical trials can be replicated in clinical practice. It can be questioned if interventions utilized in randomized controlled trials can be translated into clinical practice.

OBJECTIVES

The overall aim of this study is to examine whether the quality of the description of manipulation and mobilization interventions is sufficient for to replication of these interventions in clinical practice.

METHODS

A comprehensive literature search was performed. Two independent researchers used the Template for Intervention Description and Replication (TIDieR) which is a 12-item checklist for describing the completeness of the interventions.

RESULTS

Sixty-seven articles were included that used manipulation and/or mobilization interventions for patients with mechanical neck pain. None of the articles describe the intervention e.g. all the items on the TIDieR list. Considering item 8 (a-f) of the TIDieR checklist only one article described the used techniques completely.

CONCLUSION

Manipulation or a mobilization interventions are poorly reported in RCTs, which jeopardize the external validity of RCTs, making it difficult for clinicians and researchers to replicate these interventions.

Development of an Objective Portable Measurement Device for Spinal Joint Accessory Motion Testing

Joint accessory motion testing (JAMT) is a standard procedure used by manual therapists to assess and treat musculoskeletal disorders. Joint accessory motion (JAM) is movement that occurs between joint surfaces, and can be induced by applying force. The motion amount, end feel, symptoms, and resistance perceived by therapists during test procedures are recorded as evidence for the diagnosis, prognosis, treatment decision making, and intervention outcome. However, previous studies have shown that accessory motion tests have insufficient reliability. Recently, many instruments have been developed to increase test reliability, but these instruments quantify the test results with a single probe and utilize the external environment as a reference. Therefore, the measured displacement amount may be affected by other spinal segments. This study proposes an objective portable measurement device with two indenter probes for spinal JAMT, wherein the JAM was quantified by displacement and force measurements between two bones. The instrument was verified with a homemade spinal simulator and computer simulation. The results showed that the force-displacement curves measured by the JAMT device (JAMTD) and those simulated by the computer model exhibited similar characteristics. Moreover, a two-probe measurement could distinguish the differences in stiffness better than a one-probe measurement.

Vertebral Displacements and Muscle Activity During Manual Therapy: Distinct Behaviors Between Spinal Manipulation and Mobilization

OBJECTIVE

The purpose of this study was to compare vertebral displacements (absolute and relative) and muscle responses induced by spinal manipulative therapy of short (spinal manipulation) and long (spinal mobilization) impulse duration.

METHODS

Twenty-five healthy adults (without thoracic pain) were recruited for this crossover study. Six spinal manipulative therapies (255 N peak force) of different impulse durations (100, 125, 200, 500, 1000, and 1500 ms) were delivered to each participant's T7 transverse process using a mechanical device. Impulse duration effect on the vertebral displacement (absolute displacement of T6, T7, and T8 and relative displacement between T7 and T6 and between T7 and T8) and the thoracic muscle response (surface electromyography) were assessed using mixed-model analyses of variance and predefined linear trend analyses.

RESULTS

Results showed a linear increase in the absolute vertebral displacement for T8 (P = .002) and a linear decrease in the T7/T6 and T7/T8 relative displacement (P < .0001) when impulse duration was increased. The data of 24 participants were available for electromyography analysis. A significant main effect of impulse duration on surface electromyography response was observed (P < .0001, ƞ_p²=0.43). Planned comparisons for a linear trend between these variables revealed a negative relationship (P < .0001). Only 13 of the 24 participants with available data presented a muscle response at every impulse duration.

CONCLUSION

These results support the assumption that spinal manipulation and spinal mobilization might operate under distinct mechanisms.

The effect of real-time feedback on learning lumbar spine joint mobilization by entry-level doctor of physical therapy students: a randomized, controlled, crossover trial

OBJECTIVE

To examine the effects of real-time, objective feedback on learning lumbar spine joint mobilization techniques by entry-level Doctor of Physical Therapy (DPT) students.

METHODS

A randomized, controlled, crossover design was used. Twenty-four 1st Year DPT students were randomized into two groups. Group 1 (n = 12) practiced with the real-time feedback device first and then without it, while Group 2 (n = 12) practiced without the device first and then with it. Both practice periods with and without the device were 4 weeks long. Data were collected at Baseline, 5 weeks, 11 weeks, and 16 weeks. The crossover period was 5 weeks long, during which neither group practiced with or without the device. Eight force parameters were measured: R1 force; R2 force; Grade III and Grade IV mean peak force, frequency, and amplitude.

RESULTS

When students practiced with the real-time feedback device, they more closely matched the reference standard for two outcomes: 1) the mean difference in R2 force between student and reference standard was better with device (38.0 ± 26.7 N) than without it (51.0 ± 38.5 N); P = .013; and 2) the mean difference in Grade III peak to peak amplitude force was also better with device (8.9 ± 9.3 N) than without it (11.8 ± 11.0); P = .026. All other force parameters improved when students practiced with the real-time feedback device, however, the differences between when they practiced without the device were not statistically significant.

DISCUSSION

Real-time, objective feedback using a direct force measurement device improved learning for some aspects of lumbar spine joint mobilization by entry-level physical therapy students.

LEVEL OF EVIDENCE

2b.

A pilot study of the effect of force feedback training on students learning flexion-distraction chiropractic technique

OBJECTIVE

We compared traditional training alone and with the addition of force feedback training for learning flexion-distraction chiropractic technique.

METHODS

Participants were randomly allocated to two groups (traditional or traditional plus force feedback training). Students' forces were measured before training and after force feedback training. Students rated the helpfulness of the training and the comfort of the force transducer.

RESULTS

Thirty-one students were enrolled. Both groups delivered similar forces at baseline. Group 1 students' subsequent force measurements were higher after force feedback training. Group 2 students' forces were unchanged. Group 2 students were trained with force feedback for week 2 of the class, and forces were higher after feedback and similar to those in group 1. Students rated the training as very or somewhat helpful. Students also experienced discomfort as a patient and a student-doctor due to the force transducer that was used. Students who received force feedback training learned to deliver higher forces, which were closer to the forces delivered by experienced doctors of chiropractic. Students who did not receive force feedback continued to deliver lower forces.

CONCLUSION

Force feedback helped students deliver forces closer to the desired force level and to learn this delivery faster than students who were not trained with force feedback.

An empirical, pragmatic approach applying reflection in interaction approach to manual therapy treatments

Background: Most literature on decision processes within physiotherapy relates to "reasoning that results in action" - decisions based on information including assessments that are gathered prior to treatment decisions. A process of "reasoning in interaction" that is often used, particularly by expert clinicians, has received less attention. Objective:  To provide a theoretical and practical approach to applying reasoning in interaction in a musculoskeletal setting. Methods: The theory is: If an impairment that can be directly targeted by treatment (i.e. pain or limitation of passive movement) is related to patient's active impairments and functional limitations, then moment-to-moment changes in the targeted impairment can be used as feedback to guide real-time treatment modification before formal reassessment of functional limitations and other impairments. Results: Applying the theory to manual therapy results in parameters of techniques such as force, speed, direction and duration no longer being pre-determined, but rather being continually adjusted in real-time according to feedback from the patient through both therapist perception (changes in movement quantity or quality) and patient verbal responses. Conclusion: A process of continuous decision-making is described that the authors believe is used by many experienced clinicians but has not previously been adequately described in the literature. .

Short-Term Effects of Different Rates of Thoracic Mobilization on Pressure Pain Thresholds in Asymptomatic Individuals: A Randomized Crossover Trial

Objective

The primary aim of this study was to determine the effects of different rates of thoracic spine passive accessory intervertebral mobilization (PAIVM) on pressure pain threshold (PPT) at T4. The secondary aim was to investigate the widespread effects of different rates of thoracic PAIVM.

Methods

Twenty asymptomatic participants were randomly assigned to 3 experimental conditions: posteroanterior rotatory thoracic PAIVM at 2 Hz, 0.5 Hz, and placebo. Each participant received all 3 experimental conditions in a random order with a washout period of at least 48 hours between each procedure. The PPT was measured in 3 different points: pre-treatment, immediately after, and 15 minutes after the treatment at C7 and T4 spinous process, first interossei dorsal on the right and left hands and tibial tuberosity bilaterally. A repeated-measures analysis of covariance adjusted by baseline values was used to assess between-group differences at each point. Pairwise comparisons were adjusted for multiple tests with a Bonferroni correction. A P value < .05 was considered significant.

Results

There was no between-group differences on PPT at T4 when comparing 0.5 Hz (mean difference -0.29; 95% CI -0.99 to 0.42; P = .999) or 2 Hz (mean difference -0.37; 95% CI -1.1 to 0.33; P = .528) to placebo.

Conclusion

None of the mobilization techniques in this study (0.5 Hz, 2 Hz, and placebo) showed a significant change of PPT both locally and at distant sites at any point in asymptomatic participants.

Effect of Blocked Versus Random Practice on Physical Therapy Students' Manual Force Modulation

This study examined (a) the effect of practice organization on learning to modulate manual force, and (b) the effect of force magnitude on ability to accurately reproduce force. I randomly assigned 52 novice physical therapy students to either blocked or random practice schedules as they learned to apply different manual forces. I tested students immediately after training and one week later, using a three-way mixed design analysis of variance to assess the effects of practice organization (random vs. blocked), test (immediate posttest vs. retention test), and force (high vs. low) on ability to modulate manual forces. I found that blocked versus random practice, led to more accurate force application at the posttest and retention test, F(1, 50) = 5.57, p < .05; both practice groups performed more accurately at the posttest than at the retention test, F(1, 50) = 5.6, p < .05, and both performed more accurately at the lower, compared with the higher, force level, F(1, 50) = 60.9, p < .05. These findings support use of a blocked' practice schedule for this motor training, though relevant contextual interference moderators may include such variables as nature of the task, learners' skill levels, and practice time. In addition, higher forces resulted in greater errors and must be considered in preparing for and engaging in clinical practice.

Comparison of high, medium and low mobilization forces for increasing range of motion in patients with hip osteoarthritis: A randomized controlled trial

BACKGROUND

Manual therapy has been shown to increase range of motion (ROM) in hip osteoarthritis (OA). However, the optimal intensity of force during joint mobilization is not known.

OBJECTIVE

To compare the effectiveness of high, medium and low mobilization forces for increasing range of motion (ROM) in patients with hip OA and to analyze the effect size of the mobilization.

DESIGN

Randomized controlled trial.

METHODS

Sixty patients with unilateral hip OA were randomized to three groups: low, medium or high force mobilization group. Participants received three treatment sessions of long-axis distraction mobilization (LADM) in open packed position and distraction forces were measured at each treatment. Primary outcomes: passive hip ROM assessed before and after each session.

SECONDARY OUTCOMES

pain recorded with Western Ontario and McMaster Universities (WOMAC) pain subscale before and after the three treatment sessions.

RESULTS

Hip ROM increased significantly (p < 0.05) in the high-force mobilization group (flexion: 10.6°, extension: 8.0°, abduction:6.4°, adduction: 3.3°, external rotation: 5.6°, internal rotation: 7.6°). These improvements in hip ROM were statistically significant (p < 0.05) compared to the low-force group. There were no significant changes in the low-force and medium-force groups for hip ROM. No significant differences in hip pain were found between treatment groups.

CONCLUSION

A high force LADM in open packed position significantly increased hip ROM in all planes of motion compared to a medium or low force mobilization in patients with hip OA. A specific intensity of force mobilization appears to be necessary for increasing ROM in hip OA.

Development of a disposable force-sensing glove for clinicians and demonstration of its force measurements on patients during rehabilitation following anterior cruciate ligament reconstruction surgery

For many clinicians, their effectiveness is dependent on the magnitude of forces they manually apply to their patients. However, current state-of-the-art care strategies lack quantitative feedback, making it difficult to provide consistent care over time and among multiple clinicians. To provide real-time quantitative feedback to clinicians, we have developed a disposable glove with a force sensor embedded in the fingertips or palm. The sensor is based on the fiber-optic bendloss effect whereby light intensity from an infrared source is attenuated as the fiber is bent between a series of corrugated teeth. The sensor fabricated has a very low profile (10×7×1  mm) and has demonstrated high sensitivity, accuracy, range, and durability. Force feedback up to 90 N with an average force threshold at 0.19 N and average sensor resolution at 0.05 N has been demonstrated. A preliminary clinical study has also been conducted with anterior cruciate ligament reconstruction patients who show significant range of motion improvement when treated with the force-sensing glove.

Different mechanosensory stimulations of the lower back elicit specific changes in hemodynamics and oxygenation in cortical sensorimotor areas-A fNIRS study

BACKGROUND AND OBJECTIVES

This study aimed at investigating the feasibility of functional near-infrared spectroscopy (fNIRS) to measure changes in cerebral hemodynamics and oxygenation evoked by painful and nonpainful mechanosensory stimulation on the lower back. The main objectives were to investigate whether cortical activity can be (1) detected using functional fNIRS, and (2) if it is possible to distinguish between painful and nonpainful pressure as well as a tactile brushing stimulus based on relative changes in oxy- and deoxyhemoglobin ([O2Hb] and [HHb]).

METHODS

Twenty right-handed subjects (33.5 ± 10.7 years; range 20-61 years; 8 women) participated in the study. Painful and nonpainful pressure stimulation was exerted with a thumb grip perpendicularly to the spinous process of the lumbar spine. Tactile stimulation was realized by a one-finger brushing. The supplementary motor area (SMA) and primary somatosensory cortex (S1) were measured bilaterally using a multichannel continuous-wave fNIRS imaging system.

RESULTS

Characteristic relative changes in [O2Hb] in the SMA and S1 after both pressure stimulations (corrected for multiple comparison) were observed. [HHb] showed only much weaker changes (uncorrected). The brushing stimulus did not reveal any significant changes in [O2Hb] or [HHb].

CONCLUSION

The results indicate that fNIRS is sensitive enough to detect varying hemodynamic responses to different types of mechanosensory stimulation. The acquired data will serve as a foundation for further investigations in patients with chronic lower back pain. The future aim is to disentangle possible maladaptive neuroplastic changes in sensorimotor areas during painful and nonpainful lower back stimulations based on fNIRS neuroimaging.

Cortical Sensorimotor Processing of Painful Pressure in Patients with Chronic Lower Back Pain-An Optical Neuroimaging Study using fNIRS

In this study we investigated sensorimotor processing of painful pressure stimulation on the lower back of patients with chronic lower back pain (CLBP) by using functional near-infrared spectroscopy (fNIRS) to measure changes in cerebral hemodynamics and oxygenation. The main objectives were whether patients with CLBP show different relative changes in oxy- and deoxyhemoglobin ([O2Hb] and [HHb]) in the supplementary motor area (SMA) and primary somatosensory cortex (S1) compared to healthy controls (HC). Twelve patients with CLBP (32 ± 6.1 years; range: 24-44 years; nine women) and 20 HCs (33.5 ± 10.7 years; range 22-61 years; eight women) participated in the study. Painful and non-painful pressure stimulation was exerted with a thumb grip perpendicularly to the spinous process of the lumbar spine. A force sensor was attached at the spinous process in order to control pressure forces. Tactile stimulation was realized by a one-finger brushing. Hemodynamic changes in the SMA and S1 were measured bilaterally using a multi-channel continuous wave fNIRS imaging system and a multi-distant probe array. Patients with CLBP showed significant stimulus-evoked hemodynamic responses in [O2Hb] only in the right S1, while the HC exhibited significant [O2Hb] changes bilaterally in both, SMA and S1. However, the group comparisons revealed no significant different hemodynamic responses in [O2Hb] and [HHb] in the SMA and S1 after both pressure stimulations. This non-significant result might be driven by the high inter-subject variability of hemodynamic responses that has been observed within the patients group. In conclusion, we could not find different stimulus-evoked hemodynamic responses in patients with CLBP compared to HCs. This indicates that neither S1 nor the SMA show a specificity for CLBP during pressure stimulation on the lower back. However, the results point to a potential subgrouping regarding task-related cortical activity within the CLBP group; a finding worth further research.

Reorganization in Secondary Somatosensory Cortex in Chronic Low Back Pain Patients

STUDY DESIGN

A cross-sectional comparative study between chronic low back pain (CLBP) patients and healthy control subjects.

OBJECTIVE

The aim of this study was to investigate reorganization in the sensory cortex by comparing cortical activity due to mechanosensory stimulation of the lumbar spine in CLBP patients versus a control group by using functional magnetic resonance imaging (fMRI).

SUMMARY OF BACKGROUND DATA

LBP is now the number 1 condition across the world in terms of years living with a disability. There is growing evidence that maladaptive changes in the processing of sensory input by the central nervous system are central to understanding chronic (back) pain.

METHODS

Nonpainful, posterior-anterior (PA) movement pressure was applied manually to lumbar vertebrae at L1, L3, and L5 in 13 healthy subjects and 13 CLBP patients. The manual pressure (30 N) was monitored and controlled using sensors. A randomized stimulation protocol was used consisting of 51 pressure stimuli of 5 seconds duration. fMRI data analysis was performed for the group activation within the primary and secondary sensory cortices (S1 and S2, respectively) and the representation of the individual vertebrae was extracted and statistically analyzed.

RESULTS

Nonpainful PA pressure revealed no cortical reorganization in S1. In contrast, the extent of S2 activation in the CLBP group was significantly reduced in both hemispheres. In the control group, a somatotopy was identified for the lumbar vertebrae between L1 and L3, respectively, and L5 in S2 of the right hemisphere. Most importantly, a blurring of the somatotopic representation of the lumbar spine in S2 was observed in the patient group.

CONCLUSION

Together, these maladaptive changes suggest a reorganization of higher-order processing for sensory information in CLBP patients that might have implications for a decreased sensory acuity, also related to body perception and subsequent altered functioning of the lumbar spine.

LEVEL OF EVIDENCE

2.

Manual and Instrument Applied Cervical Manipulation for Mechanical Neck Pain: A Randomized Controlled Trial

OBJECTIVE

The purpose of this study was to compare the effects of 2 different cervical manipulation techniques for mechanical neck pain (MNP).

METHODS

Participants with MNP of at least 1 month's duration (n = 65) were randomly allocated to 3 groups: (1) stretching (control), (2) stretching plus manually applied manipulation (MAM), and (3) stretching plus instrument-applied manipulation (IAM). MAM consisted of a single high-velocity, low-amplitude cervical chiropractic manipulation, whereas IAM involved the application of a single cervical manipulation using an (Activator IV) adjusting instrument. Preintervention and postintervention measurements were taken of all outcomes measures. Pain was the primary outcome and was measured using visual analogue scale and pressure pain thresholds. Secondary outcomes included cervical range of motion, hand grip-strength, and wrist blood pressure. Follow-up subjective pain scores were obtained via telephone text message 7 days postintervention.

RESULTS

Subjective pain scores decreased at 7-day follow-up in the MAM group compared with control (P = .015). Cervical rotation bilaterally (ipsilateral: P = .002; contralateral: P = .015) and lateral flexion on the contralateral side to manipulation (P = .001) increased following MAM. Hand grip-strength on the contralateral side to manipulation (P = .013) increased following IAM. No moderate or severe adverse events were reported. Mild adverse events were reported on 6 occasions (control, 4; MAM, 1; IAM, 1).

CONCLUSION

This study demonstrates that a single cervical manipulation is capable of producing immediate and short-term benefits for MNP. The study also demonstrates that not all manipulative techniques have the same effect and that the differences may be mediated by neurological or biomechanical factors inherent to each technique.

Using the template for intervention description and replication (TIDieR) as a tool for improving the design and reporting of manual therapy interventions

The detailed reporting of any research intervention is crucial to evaluate its applicability into a routinely practice-based context. However, it has been estimated that, especially in non-pharmacological interventions, the published literature typically includes incomplete intervention details. In the field of manual medicine, where interventions are delivered with a high degree of individualization and variability, poorly reported studies could compromise internal and external validity of the results. Among the various initiatives that have been undertaken to improve the intervention description, the Template for Intervention Description and Replication (TIDieR) has to be highlighted as the most promising. TIDieR offers both to researchers and clinicians a helpful and comprehensive guidance on how manual therapy interventions have to be designed and reported, taking into account the clinical complexity of manual therapy and the need to satisfy research gold standards.

An investigation into the effects of applying a lumbar Maitland mobilisation at different frequencies on sympathetic nervous system activity levels in the lower limb

BACKGROUND

Oscillatory Maitland mobilisations are commonly used in the management of lower back pain with research suggesting that mobilisations at 2 Hz may excite the sympathetic nervous system (SNS) more than sustained pressure glides or 0.5 Hz oscillatory mobilisations.

OBJECTIVES

Investigate the effects of increasing the oscillation frequency greater than 2 Hz.

DESIGN

A double-blind, placebo-controlled, independent group experimental design.

METHOD

Sixty healthy male volunteers were randomly allocated to one of four groups; a control group (no contact), placebo group (sustained static pressure to L4 vertebra), and two intervention groups receiving a centrally applied postero-anterior mobilisation applied at either 2 Hz or 3 Hz for three 1-min periods. SNS activity was recorded by a blinded data collector by continuous skin conductance (SC) activity levels in the feet using a Biopac MP35 electrodermal amplifier. Participants were blinded to their group allocation which was further validated by a post-experiment questionnaire (p > 0.05).

RESULTS

The magnitude of sympathoexcitatory response was greatest for the 3 Hz mobilisation (20%) compared with the 2 Hz mobilisation (12%), placebo (-1%) and control conditions (3%). Only the 3 Hz group demonstrated statistical significance when compared to placebo intervention (p = 0.002), and the control group (p = 0.02).

CONCLUSION

SC changes reflect those of previous studies using lumbar mobilisations at 2 Hz, however the 3 Hz group was found to have a greater magnitude of effect worthy of consideration within research and clinical settings. These findings provide preliminary evidence to support the use of 3 Hz oscillatory mobilisations to affect a greater magnitude of SNS activity than those previously reported (0.5, 1.5 and 2 Hz).

Do experienced physiotherapists and final year physiotherapy trainees apply similar force during posterior-to-anterior lumbar mobilization techniques?

This study aims to quantify the force applied during posterior-to-anterior lumbar vertebrae mobilizations of different grades (I to IV) and compare that force between experienced physiotherapists and final year physiotherapy students. Four experienced physiotherapists and four final year physiotherapy students participated in this study along with five healthy asymptomatic individuals. A manual therapy table positioned over three force plates allowed for measurements of the force oscillation frequency and intensity applied during grade I, II, III and IV posterior-to-anterior (PA) mobilizations at two lumbar vertebral levels (L2 and L4). Mixed model ANOVAs were used to compare the force applied between the experienced physiotherapists and students, and between the various grades. The results showed that the mean oscillation frequency was similar between the groups for all grades. Grade I and grade IV PA mobilizations showed similar mean oscillation frequency as did grade II and III PA mobilizations. The minimum and maximum force applied was higher for the physiotherapists than for the students for all mobilization grades (p values < 0.05). Similar mean maximum force values were recorded for PA mobilizations between grade I and II and between grade III and grade IV. Grade III and IV PA mobilizations yielded higher mean maximum force values than those recorded during grade I and grade II PA mobilizations. The method used in this study allowed for quantification of the force applied during lumbar PA mobilizations. Experienced physiotherapists apply greater force than physiotherapy students across all grades, despite similar oscillation frequency.

Dose optimization for spinal treatment effectiveness: a randomized controlled trial investigating the effects of high and low mobilization forces in patients with neck pain

STUDY DESIGN

Randomized controlled trial. Objective To determine if force magnitude during posterior-to-anterior mobilization affects immediate and short-term outcomes in patients with chronic, nonspecific neck pain.

BACKGROUND

The optimal dose of mobilization to effectively treat patients with neck pain is not known.

METHODS

Patients with neck pain of at least 3 months in duration (n = 64) were randomized to receive a single treatment of posterior-to-anterior mobilization applied with 30 N or 90 N of mean peak force (3 sets of 30 seconds) or a placebo (detuned laser) on the spinous process at the painful spinal level. Pressure pain threshold, pain measured with a visual analog scale (range, 0-100 mm), cervical range of motion, and spinal stiffness at the painful spinal level (measured with a custom device and normalized as a percentage of C7 stiffness) were assessed before, immediately after, and at a mean ± SD follow-up of 4.0 ± 1.8 days following treatment. Repeated-measures analysis of covariance and Bonferroni-adjusted post hoc tests determined group differences for each outcome measure after treatment and at follow-up.

RESULTS

At follow-up, the 90-N group had less pain than the 30-N group (mean difference, 11.3 mm; 95% confidence interval: 0.1, 22.6 mm; P = .048) and lower stiffness than the placebo group (mean difference, 17.5%; 95% confidence interval: 4.2%, 30.9%; P = .006). These differences were not present immediately after treatment. There were no significant between-group differences in pressure pain threshold or range of motion after treatment or at follow-up.

CONCLUSION

A specific dose of mobilization, in terms of applied force, appears necessary for reducing stiffness and potentially pain in patients with chronic neck pain. Changes were not observed immediately after mobilization, suggesting that its effects are not directly mechanical.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry ( http://www.anzctr.org.au/): ACTRN12611000374965.

LEVEL OF EVIDENCE

Therapy, level 1b-.

The cortical and cerebellar representation of the lumbar spine

Eight decades after Penfield's discovery of the homunculus only sparse evidence exists on the cortical representation of the lumbar spine. The aim of our investigation was the description of the lumbar spine's cortical representation in healthy subjects during the application of measured manual pressure. Twenty participants in the prone position were investigated during functional magnetic resonance imaging (fMRI). An experienced manual therapist applied non-painful, posterior-to-anterior (PA) pressure on three lumbar spinous processes (L1, L3, and L5). The pressure (30 N) was monitored and controlled by sensors. The randomized stimulation protocol consisted of 68 pressure stimuli of 5 s duration. Blood oxygenation level dependent (BOLD) responses were analyzed in relation to the lumbar stimulations. The results demonstrate that controlled PA pressure on the lumbar spine induced significant activation patterns. The major new finding was a strong and consistent activation bilaterally in the somatosensory cortices (S1 and S2). In addition, bilateral activation was located medially in the anterior cerebellum. The activation pattern also included other cortical areas probably related to anticipatory postural adjustments. These revealed stable somatosensory maps of the lumbar spine in healthy subjects can subsequently be used as a baseline to investigate cortical and subcortical reorganization in low back pain patients.

A simulated passive intervertebral motion task: observations of performance in a cross-sectional study

INTRODUCTION

Passive motion palpation is an integral component in examination, diagnosis or classification, and treatment of persons with mechanical disorders of the cervical spine. If the magnitude of force application during passive movement assessment is associated with greater palpatory accuracy has not been established.

METHODS

This investigation used a novel mechanical model as a basis for assessing the palpatory force of students and clinicians. The model included multiple palpable resistance and displacement levels similar to that observed in humans. The ability of the subjects to discriminate the various levels of resistance and displacement offered by the model was concurrently measured.

RESULTS

Large variability occurred in the amount of force applied by the subjects in completing the palpatory examination. The data indicated no major differences in palpatory accuracy across the student and clinician groups with different training and experience levels beyond basic competency. Those subjects applying less force in the palpatory exam demonstrated greater accuracy of palpatory assessment with one measure.

DISCUSSION

The data indicate training and experience had minimal relationship to palpatory interpretation precision beyond the basic level and individual natural discriminatory ability may be a factor in accuracy of palpatory skill. The results demonstrate remarkable inconsistency in palpatory force among examiners and suggest that palpatory accuracy may be related to less force application.

Biomechanical measures of knee joint mobilization

BACKGROUND AND PURPOSE

The purpose of this study was to quantify the biomechanical properties of specific manual therapy techniques in patients with symptomatic knee osteoarthritis.

METHODS

Twenty subjects (7 female/13 male, age 54±8 years, ht 1·7±0·1 m, wt 94·2±21·8 kg) participated in this study. One physical therapist delivered joint mobilizations (tibiofemoral extension and flexion; patellofemoral medial-lateral and inferior glide) at two grades (Maitland's grade III and grade IV). A capacitance-based pressure mat was used to capture biomechanical characteristics of force and frequency during 2 trials of 15 second mobilizations. Statistical analysis included intraclass correlation coefficient (ICC(3,1)) for intrarater reliability and 2×4 repeated measures analyses of variance and post-hoc comparison tests.

RESULTS

Force (Newtons) measurements (mean, max.) for grade III were: extension 45, 74; flexion 39, 61; medial-lateral glide 20, 34; inferior glide 16, 27. Force (Newtons) measurements (mean, max.) for grade IV were: extension 57, 76; flexion 47, 68; medial-lateral glide 23, 36; inferior glide 18, 35. Frequency (Hz) measurements were between 0·9 and 1·2 for grade III, and between 2·1 and 2·4 for grade IV. ICCs were above 0·90 for almost all measures.

DISCUSSION AND CONCLUSION

Maximum force measures were between the ranges reported for cervical and lumbar mobilization at similar grades. Mean force measures were greater at grade IV than III. Oscillation frequency and peak-to-peak amplitude measures were consistent with the grade performed (i.e. greater frequency at grade IV, greater peak-to-peak amplitude at grade III). Intrarater reliability for force, peak-to-peak amplitude and oscillation frequency for knee joint mobilizations was excellent.

A structured review of spinal stiffness as a kinesiological outcome of manipulation: its measurement and utility in diagnosis, prognosis and treatment decision-making

PURPOSE

To review and discuss the methods used for measuring spinal stiffness and factors associated with stiffness, how stiffness is used in diagnosis, prognosis, and treatment decision-making and the effects of manipulative techniques on stiffness.

METHODS

A systematic search of MEDLINE, EMBASE, CINAHL, AMED and ICL databases was conducted. Included studies addressed one of four constructs related to stiffness: measurement, diagnosis, prognosis and/or treatment decision-making, and the effects of manipulation on stiffness. Spinal stiffness was defined as the relationship between force and displacement.

RESULTS

One hundred and four studies are discussed in this review, with the majority of studies focused on the measurement of stiffness, most often in asymptomatic persons. Eight studies investigated spinal stiffness in diagnosis, providing limited evidence that practitioner-judged stiffness is associated with radiographic findings of sagittal rotational mobility. Fifteen studies investigated spinal stiffness in prognosis or treatment decision-making, providing limited evidence that spinal stiffness is unlikely to independently predict patient outcomes, though stiffness may influence a practitioner's application of non-thrust manipulative techniques. Nine studies investigating the effects of manipulative techniques on spinal stiffness provide very limited evidence that there is no change in spinal stiffness following thrust or non-thrust manipulation in asymptomatic individuals and non-thrust techniques in symptomatic persons, with only one study supporting an immediate, but not sustained, stiffness decrease following thrust manipulation in symptomatic individuals.

CONCLUSIONS

The existing limited evidence does not support an association between spinal stiffness and manipulative treatment outcomes. There is a need for additional research investigating the effects of manipulation on spinal stiffness in persons with spinal pain.