Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Background and purpose — In total hip replacements, stem design may affect the occurrence of periprosthetic femoral fracture. We studied risk factors for fractures around and distal to the 2 most used cemented femoral stems in Sweden. Patients and methods — This is a register study including all standard primary Lubinus SPII and Exeter Polished stems operated in Sweden between 2001 and 2009. The outcome was any kind of reoperation due to fracture around (Vancouver type B) or distal to the stem (Vancouver type C), with use of age, sex, diagnosis at primary THR, and year of index operation as covariates in a Cox regression analysis. A separate analysis of the primary osteoarthritis patient group was done in order to evaluate eventual influence of the surgical approach (lateral versus posterior) on the risk for Vancouver type B fractures. Results — The Exeter stem had a 10-times (95% CI 7–13) higher risk for type B fractures, compared with the Lubinus, while no statistically significant difference was noticed for type C fractures. The elderly, and patients with hip fracture or idiopathic femoral head necrosis, had a higher risk for both fracture types. Inflammatory arthritis was a risk factor only for type C fractures. Type B fractures were more common in men, and type C in women. A lateral approach was associated with decreased risk for Type B fracture. Interpretation — Stem design influenced the risk for type B, but not for type C fracture. The influence of surgical approach on the risk for periprosthetic femoral fracture should be studied further.

The incidence of PPFFs has increased in Sweden during the period 2001 to 2011. The improved reporting of type C fractures, after data-linking, revealed an almost 4 times higher incidence compared to previous register studies in Sweden.

Aims We investigated patient characteristics and outcomes of Vancouver type B periprosthetic fractures treated with femoral component revision and/or osteosynthesis. Patients and Methods The study utilized data from the Swedish Hip Arthroplasty Register (SHAR) and information from patient records. We included all primary total hip arthroplasties (THAs) performed in Sweden since 1979, and undergoing further surgery due to Vancouver type B periprosthetic femoral fracture between 2001 and 2011. The primary outcome measure was any further reoperation between 2001 and 2013. Cross-referencing with the National Patient Register was performed in two stages, in order to identify all surgical procedures not recorded on the SHAR. Results Out of 1381 Vancouver type B fractures that fulfilled the inclusion criteria, 257 underwent further reoperation by the end of 2013. Interprosthetic and Type B1 fractures had a higher risk for reoperation. For B1 fractures, the rate of reoperation did not differ (p = 0.322) after use of conventional (26%) or locking plate osteosynthesis (19%). No significant differences were observed between cemented, cementless monoblock, and cementless modular revision components for the treatment of type B2 and B3 fractures. Conclusion In this country-specific study, the choice of locking or conventional plates for the treatment of type B1, and cemented or cementless femoral components fixation for B2 and B3 fractures, had no significant influence on risk for reoperation. Interprosthetic fractures adversely affected the outcome of treatment of type B fractures. Differences in the patient characteristics of the compared groups were observed. Cite this article: Bone Joint J 2019;101-B:1447–1458.