The outcome of post-surgical hip prosthesis rehabilitation: results from a monocentric cohort study

Background: With the increase in life expectancy, more patients are undergoing total hip arthroplasty, primarily due to the rising incidence of osteoarthritis. The outcomes of rehabilitation following these surgical interventions are influenced by various factors. This study aims to explore the impact of age, gender, and body mass index (BMI) on pain and functional and rehabilitative outcomes after surgical hip prosthesis rehabilitation. Methods: We enrolled all patients admitted to a private clinic from January 2021 to December 2023 for rehabilitation after unilateral hip arthroplasty. For each patient, we collected data of Barthel Index, Tinetti Scale, Numeric Rating Scale (NRS), and range of motion (ROM) at the beginning and end of the hospitalization. We assessed whether the evaluated outcomes differed based on gender, age, and BMI using the Mann-Whitney and Kruskal-Wallis tests. Results: A total of 2.167 patients were studied (56% female and 36.5% over 75 years old). Male patients, adults (18-64 years), and those with a BMI < 30 showed higher values of Barthel Index, Tinetti Scale, and ROM at both admission and discharge (p < 0.05), along with significantly lower NRS scores. Each subgroup based on age, gender, and BMI showed an improvement in NRS (difference between admission and discharge) of at least 40%, it was about 50% for men and adults. The improvement in ROM (difference between admission and discharge) was more than 10% in both active and passive flexion, around 20% for passive abduction, and 50% for active abduction, with no significant differences based on age, gender, or BMI. Conclusions: Despite the absence of specific contraindications for arthroplasty procedures, a high BMI, age over 75 years, and female gender are associated with slightly worse functional and rehabilitation outcomes compared to other patients undergoing the same procedures. A preoperative screening for the evaluation of osteopenia, osteoporosis, and BMI could be a valuable tool for studying and improving outcomes in these patients.