Quantitative Measurement of Rigidity in Parkinson’s Disease: A Systematic Review

Abstract

Rigidity is one of the cardinal symptoms of Parkinson’s disease (PD). Present in up 89% of cases, it is typically assessed with clinical scales. However, these instruments show limitations due to their subjectivity and poor intra- and inter-rater reliability. To compile all of the objective quantitative methods used to assess rigidity in PD and to study their validity and reliability, a systematic review was conducted using the Web of Science, PubMed, and Scopus databases. Studies from January 1975 to June 2019 were included, all of which were written in English. The Strengthening the Reporting of observational studies in Epidemiology Statement (STROBE) checklist for observational studies was used to assess the methodological rigor of the included studies. Thirty-six studies were included. Rigidity was quantitatively assessed in three ways, using servomotors, inertial sensors, and biomechanical and neurophysiological study of muscles. All methods showed good validity and reliability, good correlation with clinical scales, and were useful for detecting rigidity and studying its evolution. People with PD exhibit higher values in terms of objective muscle stiffness than healthy controls. Rigidity depends on the angular velocity and articular amplitude of the mobilization applied. There are objective, valid, and reliable methods that can be used to quantitatively assess rigidity in people with PD.

Trunk Range of Motion Is Related to Axial Rigidity, Functional Mobility and Quality of Life in Parkinson’s Disease: An Exploratory Study

“…In previous studies, several authors have used technological evaluations with isokinetic dynamometers to examine trunk rigidity in PD subjects, thanks to the mobilization of the trunk at desired speeds throughout the available ROM, recording the information relative to the offered resistance as an objective measure of rigidity [15,18,23,24]. Other technologies like inertial sensors and biomechanical and neurophysiological muscle measurements have been described [25], but all these evaluations techniques are rarely available in daily clinical practice since equipment is expensive, and its use is time consuming and requires complex data analysis.…”

Neuromechanical Assessment of Activated vs. Resting Leg Rigidity Using the Pendulum Test Is Associated With a Fall History in People With Parkinson’s Disease

“…Other instrumented clinical tests allow the evaluation of objective continuous parameters overcoming the limitations of the UPDRS rating scale (i.e., low resolution, inter-and intra- rater unreliability, ceiling effect), which include surface electromyography (Eisen, 1987 ; Andreeva and Khutorskaya, 1996 ), myometry (Marusiak et al, 2010 ), and/or torque measuring devices (Kirollos et al, 1996 ; Patrick et al, 2001 ; Endo et al, 2009 ; Xia et al, 2011 ; Powell et al, 2012 ; Zetterberg et al, 2015 ). However, to the best of our knowledge, all the methods previously proposed in the literature focused on the objective quantification of upper limb rigidity (Ferreira-Sánchez et al, 2020 ). The biomechanical outcomes of the pendulum test can be easily evaluated through simple observation of the leg swing or by using affordable devices equipped with gyroscope (Yeh et al, 2016 ) or simple video source (i.e., markerless motion capture, Mathis et al, 2018 ), making it feasible for standard clinical practice and telemedicine.…”

“…The biomechanical outcomes of the pendulum test can be easily evaluated through simple observation of the leg swing or by using affordable devices equipped with gyroscope (Yeh et al, 2016 ) or simple video source (i.e., markerless motion capture, Mathis et al, 2018 ), making it feasible for standard clinical practice and telemedicine. For example, automated analysis of the pendulum test could be implemented into smartphones (Prince et al, 2018 ) whereas prior methods require expensive additional devices, data processing, and technical assistance (Ferreira-Sánchez et al, 2020 ).…”

Biomechanical outcomes of the pendulum test characterize individual differences in activated versus resting leg rigidity in people with Parkinson’s disease

“…Other instrumented clinical tests allow the evaluation of objective continuous parameters overcoming the limitations of the UPDRS rating scale, which include surface electromyography (Eisen, 1987; Andreeva and Khutorskaya, 1996), myometry (Marusiak et al, 2010), and/or torque measuring devices (Kirollos et al, 1996; Patrick et al, 2001; Endo et al, 2009; Xia et al, 2011; Powell et al, 2012; Zetterberg et al, 2015). However, to the best of our knowledge, all the methods previously proposed in literature focused on the objective quantification of upper limbs rigidity (Ferreira-Sánchez et al, 2020). The biomechanical outcomes of the pendulum test can be easily evaluated through simple observation of the leg swing or by using affordable devices equipped with gyroscope (Yeh et al, 2016) or simple video source (i.e.…”

“…markerless motion capture, Mathis et al, 2018), making it feasible for standard clinical practice and telemedicine. For example, automated analysis of the pendulum test could be implemented into smartphones (Prince et al, 2018) whereas prior methods require expensive additional devices, data processing and technical assistance (Ferreira-Sánchez et al, 2020).…”