We examined the one-year risk of symptomatic venous thromboembolism (VTE) following primary total hip replacement (THR) among Danish patients and a comparison cohort from the general population. From the Danish Hip Arthroplasty Registry we identified all primary THRs performed in Denmark between 1995 and 2010 (n = 85 965). In all, 97% of patients undergoing THR received low-molecular-weight heparin products during hospitalisation. Through the Danish Civil Registration System we sampled a comparison cohort who had not undergone THR from the general population (n = 257 895). Among the patients undergoing THR, the risk of symptomatic VTE was 0.79% between 0 and 90 days after surgery and 0.29% between 91 and 365 days after surgery. In the comparison cohort the corresponding risks were 0.05% and 0.12%, respectively. The adjusted relative risks of symptomatic VTE among patients undergoing THR were 15.84 (95% confidence interval (CI) 13.12 to 19.12) during the first 90 days after surgery and 2.41 (95% CI 2.04 to 2.85) during 91 to 365 days after surgery, compared with the comparison cohort. The relative risk of VTE was elevated irrespective of the gender, age and level of comorbidity at the time of THR.

We concluded that THR was associated with an increased risk of symptomatic VTE up to one year after surgery compared with the general population, although the absolute risk is small.

We compared 5341 patients with an initial fracture of the hip with 633 patients who sustained a second fracture of the contralateral hip. Patients presenting with a second fracture were more likely to be institutionalised, female, older, and have lower mobility and mental test scores. There was no significant difference between the two groups with regards to the change in the level of mobility or return to their original residence at one year follow-up. However, the mortality rate in the second fracture group was significantly higher at one year (31.6% vs 27.3%, p = 0.024). In two thirds of patients, the second fracture was in the same anatomical location as the first. In an analysis of 293 patients, approximately 70% of second fractures occurred within three years of the first.

This is the largest study to investigate the outcome of patients who sustain a second contralateral hip fracture. Despite the higher mortality rate at one year, the outcome for surviving patients is not significantly different from those after initial hip fractures.