Characteristics of short-term walking ability and cognitive function in patients with postoperative hip fractures classified by age group.

[Purpose] We aimed to clarify the relationship between walking ability and cognitive function two weeks post-surgery in patients with hip fractures classified by age group. [Participants and Methods] In this single-center retrospective observational study, a total of 473 patients with hip fractures aged 75 years and older were included. The patients were classified into "old" (270 patients) and "super-old" (203 patients) groups. Multiple logistic regression analysis and receiver operating characteristic analysis were employed for data analysis. [Results] In the old group, the surgery type, Barthel index, Mini-Mental State Examination scores, and the three-day cumulative ambulation score were associated with the ability to walk independently at two weeks post-surgery. In the super-old group, Barthel index, Mini-Mental State Examination scores, and the three-day cumulative ambulation score were associated with the ability to walk independently at two weeks post-surgery. The Mini-Mental State Examination cutoff values (area under the curve) required for independent walking at two weeks post-surgery were ≥20 (0.80) for the old group and ≥24 (0.84) for the super-old group. [Conclusion] The findings suggest that maintaining cognitive function within the normal range may be important for super-old patients aged 90 years and older to be able to walk independently two weeks post-surgery.