Association of comorbidities with postoperative walking independence in patients with hip fractures: a single-center, retrospective, observational study

Hip fractures (HFs) are common in the elderly and lead to decreased walking independence. Although comorbidities may be associated with gaining walking independence, few studies have comprehensively examined baseline and preoperative clinical factors. We aimed to evaluate the effects of comorbidities on the postoperative walking independence of patients with HFs. This single-center, retrospective, observational study included patients with HFs admitted to an acute care hospital between 1 May 2022 and 1 March 2023, who before the incident were able to walk independently [functional independence measure (FIM) walk score ≥6 points]. Postoperative walking independence was evaluated using the walk item of the FIM. The Charlson comorbidity index (CCI) was used to evaluate comorbidities at admission, and the patients were divided into two categories with CCI scores of 0 points and ≥1 point. The effect of comorbidities, assessed using the CCI, on postoperative walking independence was evaluated using Cox proportional hazards analysis. Ninety-four participants were included in the analysis. The Cox proportional hazards model adjusted for potential confounders (age, operative delay and nutritional status) revealed that the CCI was significantly associated with postoperative walking independence (P < 0.05). The hazard ratio and 95% confidence interval (CI) for the CCI for postoperative walking independence were 0.40 (95% CI, 0.189–0.865). Preoperative assessment of comorbidities using the CCI may aid in predicting the postoperative walking independence of patients with HFs.