Effect of bariatric surgery on postoperative outcomes of total hip replacement in patients with hip osteoarthritis

Introduction Bariatric surgery is the most effective treatment of morbid obesity, which is common in patients with hip osteoarthritis. However, the extent to which weight loss after bariatric surgery affects the outcomes and complication rates of total hip arthroplasty (THA) has not been adequately explored. The aim of the study was to determine the impact of bariatric surgery on the results of THA and functional restoration of the lower limbs facilitating a lower risk of postoperative complications. Material and methods A retrospective-prospective cohort, single-center, controlled study included patients with hip osteoarthritis grades 3–4 as described by I. Kellgren and I. Lawrence in 1957. Patients were referred for THA, had a history of morbid obesity (body mass index > 40 kg/m2) and underwent bariatric surgery. The parameters assessed included body mass index, pain, functional status of patients measured with the Harris hip score and complication rate. Results The findings suggested a significant statistical difference (p < 0.001) in pain intensity on the first day after surgery measured in patients of the study group and the comparison group with (6.3 ± 2.3) and (7.4 ± 2.3) scores, respectively. The modified Harris Hip Score measured at 12 months of surgery reached the maximum with (90.2 ± 10.3) scores in the study group and (86.5 ± 11.6) scores in the comparison group, with a statistically significant difference in the measurements, p = 0.021. The Kaplan – Meier estimator showed a five-year survival rate of THA being 94.6 % (5.4 % complications) in the study group and 77.2 % (22.8 % complications) in the comparison group. Conclusion The bariatric surgery used in patients with morbid obesity and grade 3–4 hip osteoarthritis prior to THA facilitated a statistically significant risk of postoperative complications reduced to 17.4 % and the five-year survival rate of THA increased to 94.6 %.