Learning lumbar spine mobilization: the effects of frequency and self-control of feedback

A novel model for developing thrust joint manipulation skills: a teaching and learning perspective

Spinal and extremity thrust joint manipulation (TJM) has been shown to be an effective intervention when treating patients with various musculoskeletal conditions. Learning skilled TJM requires the proper execution of many discrete tasks. If any of these are missing, effectiveness and safety may be limited. While it is accepted that practice and feedback are important when physical therapists are learning clinical tasks, the best type of practice has not been identified for learning to perform TJM tasks. In this paper, we propose an educational model for instruction of joint manipulation that: 1) standardizes feedback terminology and 2) describes a core set of four discrete tasks (lift, drop, pull, and combination-rotation) that apply to most TJM tasks. The model includes instructing TJM tasks followed by identifying key errors related to the components of setup and thrust. Once these key errors have been identified, intentional practice activities are provided to address the noted positional and movement errors. Finally, reassessment is performed to determine if errors have diminished. This model is similar to the test-retest approach that is commonly used when treating patients. We hope this educational model will provide a framework for teaching TJM and will also foster future research.

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.

Evidence for the Effectiveness of Feedback from Wearable Inertial Sensors during Work-Related Activities: A Scoping Review

Background: Wearable inertial sensor technology (WIST) systems provide feedback, aiming to modify aberrant postures and movements. The literature on the effects of feedback from WIST during work or work-related activities has not been previously summarised. This review examines the effectiveness of feedback on upper body kinematics during work or work-related activities, along with the wearability and a quantification of the kinematics of the related device. Methods: The Cinahl, Cochrane, Embase, Medline, Scopus, Sportdiscus and Google Scholar databases were searched, including reports from January 2005 to July 2021. The included studies were summarised descriptively and the evidence was assessed. Results: Fourteen included studies demonstrated a 'limited' level of evidence supporting posture and/or movement behaviour improvements using WIST feedback, with no improvements in pain. One study assessed wearability and another two investigated comfort. Studies used tri-axial accelerometers or IMU integration (n = 5 studies). Visual and/or vibrotactile feedback was mostly used. Most studies had a risk of bias, lacked detail for methodological reproducibility and displayed inconsistent reporting of sensor technology, with validation provided only in one study. Thus, we have proposed a minimum 'Technology and Design Checklist' for reporting. Conclusions: Our findings suggest that WIST may improve posture, though not pain; however, the quality of the studies limits the strength of this conclusion. Wearability evaluations are needed for the translation of WIST outcomes. Minimum reporting standards for WIST should be followed to ensure methodological reproducibility.

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.

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.

The development and evaluation of a novel repurposing of a peripheral gaming device for the acquisition of forces applied to a hydraulic treatment plinth

This technical note details the stages taken to create an instrumented hydraulic treatment plinth for the measurement of applied forces in the vertical axis. The modification used a widely available low-cost peripheral gaming device and required only basic construction and computer skills. The instrumented treatment plinth was validated against a laboratory grade force platform across a range of applied masses from 0.5-15 kg, mock Gr I-IV vertebral mobilisations and a dynamic response test. Intraclass correlation coefficients demonstrated poor reliability (0.46) for low masses of 0.5 kg improving to excellent for larger masses up to15 kg respectively; excellent to good reliability (0.97-0.86) for the mock mobilisations and moderate reliability (0.51) for the dynamic response test. The study demonstrates how a cheap peripheral gaming device can be repurposed so that forces applied to a hydraulic treatment plinth can be collected reliably when applied in a clinically reasoned manner.