The Timed Up & Go Test for assessing patients‘ functional mobility

The Timed Up and Go (TUG) Test is a simple and widely used clinical assessment tool designed to evaluate a patient’s mobility, balance, and risk of falls. It is often used in geriatric, neurological, and rehabilitation settings (1).

Although the TUG Test involves several basic mobility tasks, such as standing up from a chair, walking, and turning around, the total time is often the only outcome parameter used.

In contrast, several recent publications show that instrumenting the TUG, for example, with inertial sensors, provides an accessible alternative for obtaining additional parameters, such as gait-related metrics, that can enhance patient assessment and improve the test’s predictive value (2-4).

The Timed Up & Go Test

The video illustrates how sensor insoles can be used to instrument the TUG test for mobility and balance assessments.

Outcomes of the Timed Up & Go Test

Instrumenting the TUG test with sensor insoles offers a range of detailed outcome parameters related to gait mechanics and timing. These insights provide valuable information for assessing mobility, identifying gait impairments, and recognizing potential underlying conditions.

Timed Up and Go Time & Stand Up Response Time

The Timed Up & Go Time represents the total time required to complete the test and is the most commonly analyzed outcome parameter of the TUG test. In addition, the Stand Up Response Time measures the time elapsed from the start signal to the moment the patient begins rising from the chair, providing an indicator of reaction speed and responsiveness. Fig-1 shows Timed Up & Go Time and Stand Up & Go time as measured outcomes of two different test executions. A normal performance (left) and poor performance (right) can be compared to reference data marked as grey zones. Reference zones represent 50% of datasets of a group of normal individuals (1st – 3rd quartile). For the dataset shown on Fig-1 right, the total time needed as well as the time needed for standing up from the chair exceed the normal reference zone significantly, which indicates poor mobility.

Schritte

Another critical outcome parameter is the number of full left and right steps, which can aid in identifying specific gait patterns associated with certain conditions (5). Fig-2 shows steps as measured outcomes of two different test executions. A normal performance (left) and poor performance (right) can again be compared to reference data marked as grey zones. For the dataset shown on Fig-2 right, more steps indicate a tippling walking style of many small steps, as often seen in Parkinsons‘ patients.

Stride Length

Stride Length refers to the distance traveled during one subsequent step of the left and right foot each and is essential for evaluating overall gait efficiency. This represents an additional outcome of a sensor insole-based assessment, offering insights into the patient’s ability to execute strides of normal length. Traditional assessment methods such as stop watch or visual observation do not include spatial gait metrics. Fig-3 shows stride lengths as measured outcomes of two different test executions. A normal performance (left) and poor performance (right) highlights that smaller, tippling steps can be identified by shorter stride length.

Stance Time, Double Support Time, Swing Time

These parameters offer insights into the temporal dynamics of the gait cycle. They are expressed as proportions of the average gait cycle time and averaged across all complete steps.

• Stance Time: The duration for which a foot remains in contact with the ground during the stance phase.
• Double Support Time: The time during which both feet are simultaneously in contact with the ground.
• Swing Time: The duration for which the foot is in the air, spanning from its final ground contact in the previous step to the next initial ground contact of the same foot.

By equipping the TUG test with sensor insoles, researchers can obtain detailed gait-related outcome parameters, enhancing their ability to assess mobility. In Fig-4, differences can be observed for the poor performance (right column) as represented by a lower cadence and longer stance and double support times.

Sensor insoles for mobility and balance testing in clinical research

Mobility assessments in research often rely on functional tests, such as the TUG test, to evaluate gait and overall movement ability.

The integration of sensor insoles into the TUG test introduces a new approach to mobility testing, offering significant advancements for clinical research. Moticon’s Sensor Insoles provide an affordable, valid, and reliable (6) tool for obtaining in-depth insights into the biomechanics of gait and mobility.

By combining precise force measurements with detailed pressure distribution, the sensor insoles enable researchers to capture a variety of gait and mobility parameters, allowing for a detailed analysis of a patient’s functional mobility and gait patterns.

The wireless, fully integrated design of Moticon’s Sensor Insoles allows the TUG test to be conducted seamlessly in clinical settings without requiring complex lab equipment. Their non-intrusive nature ensures that patients can perform the test naturally and without bias, providing reliable data for research.

Literature

1. Mancini M, Horak FB. The relevance of clinical balance assessment tools to differentiate balance deficits. Eur J Phys Rehabil Med. 2010 Jun;46(2):239-48. PMID: 20485226; PMCID: PMC3033730.
2. Ortega-Bastidas P, Gómez B, Aqueveque P, Luarte-Martínez S, Cano-de-la-Cuerda R. Instrumented Timed Up and Go Test (iTUG)-More Than Assessing Time to Predict Falls: A Systematic Review. Sensors (Basel). 2023 Mar 24;23(7):3426. doi: 10.3390/s23073426. PMID: 37050485; PMCID: PMC10098780.
3. Ponciano V, Pires IM, Ribeiro FR, Villasana MV, Crisóstomo R, Canavarro Teixeira M, Zdravevski E. Mobile Computing Technologies for Health and Mobility Assessment: Research Design and Results of the Timed Up and Go Test in Older Adults. Sensors (Basel). 2020 Jun 19;20(12):3481. doi: 10.3390/s20123481. PMID: 32575650; PMCID: PMC7349529.
4. Reinfelder S, Hauer R, Barth J, Klucken J, Eskofier BM. Timed Up-and-Go phase segmentation in Parkinson’s disease patients using unobtrusive inertial sensors. Annu Int Conf IEEE Eng Med Biol Soc. 2015;2015:5171-4. doi: 10.1109/EMBC.2015.7319556. PMID: 26737456.
5. Ponciano V, Pires IM, Ribeiro FR, Spinsante S. Sensors are Capable to Help in the Measurement of the Results of the Timed-Up and Go Test? A Systematic Review. J Med Syst. 2020 Oct 17;44(12):199. doi: 10.1007/s10916-020-01666-8. PMID: 33070247.
6. Cramer LA, Wimmer MA, Malloy P, O’Keefe JA, Knowlton CB, Ferrigno C. Validity and Reliability of the Insole3 Instrumented Shoe Insole for Ground Reaction Force Measurement during Walking and Running. Sensors (Basel). 2022 Mar 11;22(6):2203. doi: 10.3390/s22062203. PMID: 35336374; PMCID: PMC8951440.