Isolated greater trochanter fracture may impose a comparable risk on older patients' survival as a conventional hip fracture: a population-wide cohort study.

Background: Isolated greater trochanter fracture (IGT) and conventional hip fracture (HF) affect the same anatomical area but are usually researched separately. HF is associated with high mortality, and its management is well established. In contrast, IGT's effect on mortality is unknown, and its best management strategies are unclear. This study aims to compare these patient populations, their acute- and post-acute care, physical and occupational therapy use, and up to three-year mortality.

Methods: This retrospective cohort study is based on population-wide data of Estonia, where routine IGT management is non-operative and includes immediate weight-bearing as tolerated. The study included patients aged ≥ 50 years with a validated index HF or IGT diagnosis between 2009-2017. The fracture populations' acute- and post-acute care, one-year physical and occupational therapy use and three-year mortality were compared.

Results: A total of 0.4% (50/11,541) of included patients had an IGT. The baseline characteristics of the fracture cohorts showed a close resemblance, but the IGT patients received substantially less care. Adjusted analyses showed that the IGT patients' acute care was 4.5 days [3.4; 5.3] shorter they had 39.2 percentage points [25.5; 52.8] lower probability for receiving post-acute care, and they had 50 percentage points [5.5: 36]] lower probability for receiving physical and occupational therapy. The IGT and HF patients' mortality rates were comparable, being 4% and 9% for one month, 28% and 31% for one year, and 46% and 49% for three years, respectively. Crude and adjusted analyses could not find significant differences in their three-year mortality, showing a p-value of 0.6 and a hazard ratio of 0.9 [0.6; 1.3] for the IGT patients, retrospectively.

Conclusions: Despite IGT being a relatively minor injury, the evidence from this study suggests that it may impose a comparable risk on older patients' survival, as does HF due to the close resemblance of the two fracture populations. Therefore, IGT in older patients may signify an underlying need for broad-based medical attention, ensuring need-based, ongoing, coordinated care.

Trial Registration: Retrospectively registered.