Naoki Akazawa, Naomi Okawa, Kimiyuki Tamura, Hideki Moriyama
Department of Physical Therapy, Faculty of Health and Welfare, Tokushima Bunri University, 770-8514 Tokushima, Japan. E-mail: akazawa@tks.bunri-u.ac.jp
DOI: 10.2340/16501977-2279

Objective: To determine the cut-off values for knee extensor strength on the paretic and non-paretic sides and both sides combined for identifying independence in gait in chronic stroke survivors.
Design: Cross-sectional study.
Patients: Sixty chronic stroke survivors.
Methods: Functional Independence Measure (FIM) gait scores were measured, and the participants were allocated to the independent group (FIM gait score 6 or 7) or the dependent group (FIM gait score 1–5). Knee extensor strength on the paretic and non-paretic sides was measured using a handheld dynamometer.
Results: Eighteen stroke survivors were allocated to the independent group and 42 to the dependent group. The receiver operating characteristic curve analyses revealed that the cut-off values for knee extensor strength were 0. 46 Nm/kg (sensitivity 83% and specificity 67%; area under the curve (AUC) 0. 816) on the paretic side, 0. 65 Nm/kg (sensitivity 89% and specificity 55%; AUC 0. 738) on the non-paretic side and 1. 31 Nm/kg (sensitivity 83% and specificity 74%; AUC 0. 811) for both sides combined.
Conclusion: These cut-off values could help to identify stroke survivors who are no longer independent in gait because of decreasing knee extensor strength on the paretic and non-paretic sides.

Identifying independence in gait is important to prevent the decreased muscle strength and inactivity that often occur after stroke. We determined the cutoff values for knee extensor strength on the paretic and non-paretic sides and both sides combined for identifying independence in gait in chronic stroke survivors. Results of this study revealed that the cutoff values for knee extensor strength on the paretic and non-paretic sides and combined were 0.46, 0.65 and 1.31 Nm/kg, respectively. These cutoff values could help to identify stroke survivors whose dependence in gait might be caused by decreased knee extensor strength on the paretic and non-paretic sides.