Functional Mobility and Fall Risk Assessment in Lower Limb Amputees: Insights From the Timed Up and Go Test

Lower limb amputation (LLA) significantly affects mobility and increases fall risk, particularly in individuals with higher-level amputations and lower functional capacity. Effective tools to assess fall risk are essential in rehabilitation.

This study was conducted at the Department of Physical Medicine and Rehabilitation, Coimbra University Hospital (HUC), Coimbra, Portugal. This study aimed to evaluate the performance of the Timed Up and Go (TUG) test in individuals with unilateral LLA, compare TUG times by amputation level (transfemoral vs. transtibial) and functional level (K2 vs. K3), and determine the predictive value of TUG for fall risk.

A retrospective observational study was conducted with 99 unilateral LLA patients using prostheses. Participants were assessed using the TUG test, and data on demographics, functional classification, and fall history were collected. Statistical comparisons and ROC curve analysis were performed to identify significant differences and the optimal TUG cutoff for fall risk prediction.

Transfemoral amputees had significantly slower TUG times than transtibial amputees (17 vs. 12 seconds; p < 0.001). Similarly, K2 amputees in both groups had significantly longer TUG times compared to their K3 counterparts (TF: 30 seconds vs. 14 seconds; TT: 27 seconds vs. 12 seconds; p < 0.001). Individuals with a history of falls also had significantly higher TUG times (26 vs. 10 seconds; p < 0.001). A TUG threshold of 18 seconds demonstrated a sensitivity of 100% and specificity of 69% (AUC = 0.81) for fall prediction.

The TUG test is a reliable and practical tool for assessing functional mobility and fall risk in individuals with unilateral LLA. Performance varies significantly with amputation level and functional classification, and a cutoff of 18 seconds effectively identifies individuals at increased risk of falling.