Movement patterns of the functional reach test do not reflect physical function in healthy young and older participants

Abstract

The relationship of the Functional Reach Test (FRT) value with the Center of Pressure Excursion (COPE) and physical function remains unclear, and would be influenced by different population characteristics and movement patterns used in the FRT. Therefore, we explored the relationship between the FRT value and the COPE and physical function in healthy young and older individuals classified according to movement patterns. In 21 healthy young participants (42 sides) and 20 older participants (40 sides), three-dimensional motion analysis was performed during the FRT and physical function assessments. The participants were assigned to two clusters after performing a motion analysis during the FRT. Kinematic and kinetic parameters during the FRT and physical function assessment results were compared between the clusters for both groups. Correlation analysis was performed to investigate the relationships of the FRT value with COPE and physical function parameters in each cluster, in young and older individuals separately. The results showed that the hip strategies could be divided into two groups according to the degree of use (Small Hip Strategy, SHS Group; Large Hip Strategy, LHS Group). In the older SHS group, the FRT values were significantly correlated with the COPE (r = 0.75), toe grip strength (r = 0.62), and the five-times sit-to-stand test time (r = -0.52). In the older LHS group and in both groups of young individuals, there were no significant correlations of the FRT value with any parameters. The FRT value reflects the COPE and physical function only in older individuals using the SHS. This could explain previous discrepant results. As there is no simple relationship between the FRT value and physical function, it is important to include movement strategy assessment when using the FRT in clinical evaluations.

Sensor-based systems for the measurement of Functional Reach Test results: a systematic review

“… Moriyama et al (2022) examined the relationship between the FRT movement patterns and physical function in healthy young and older adults. The authors used tests that measured lower extremity muscle strength, balance, and gait speed to evaluate physical processes.…”

Differences in lower extremity kinematics during single-leg lateral drop landing of healthy individuals, injured but asymptomatic patients, and patients with chronic ankle instability- a cross-sectional observational study

“…Prior to the measurement, all participants were instructed to be barefoot, shirtless, and to wear spandex shorts in their underclothes. Markers with a diameter of 9 mm were applied to 67 locations on each subject’s entire body, following the Plug-in Gait Full-Body model ( https://www.vicon.com/ ) ( Fig 2 ) for the upper body, thighs and lower legs, and the multi-segment foot model method [ 28 , 29 ] ( Fig 3 ) for the feet. Motion analysis was performed using a three-dimensional motion analysis system (Vicon Nexus, Oxford, London, UK) with twelve infrared cameras with a sampling frequency of 100 Hz.…”

“…The missing parts of the marker trajectory data were completed by the gap-filling function in Vicon. Marker trajectory data and ground reaction force data were smoothed using the Butter worth filter in Vicon, with reference to a previous study [ 29 ].…”

“…The ground reaction force data and three-dimensional data of static standing and SLDL obtained by the above method were imported into the SIMM to create musculoskeletal models of the entire body and foot [ 29 ]. The degrees of freedom for each segment were as follows: hip joint–three, knee joint–one, ankle joint–one, subtalar joint–two, MH joint–three, and TM joint–one.…”

Effect of controlled start position on the reach distance distribution range in the functional reach test among community-dwelling older adults

“…In Japan, the functional reach test (FRT) has been used to evaluate SBA in older adults 5 , 6 , 7 ) . Mitani et al 8 ) reported a positive correlation between the reach distance and the length of movement of the center of pressure (LMCOP), and the FRT is considered a valid tool for evaluating the stability limits 9 ) . Furthermore, the FRT is associated with reach distance and the risk of falling 10 , 11 ) , and a cutoff value of approximately 6 inches (15.2 cm) to identify individuals at high risk of falling in previous studies in Western populations 10 ) .…”