An atypical femoral fracture (AFF), with a transverse
fracture radiologically through the lateral cortex is a rare but serious
condition. In order to improve our ability to identify patients
with this condition, we retrospectively surveyed all subtrochanteric,
peri-implant and diaphyseal femoral fractures in patients aged ≥ 65
years who underwent surgical treatment at our hospital between 2004
and 2011. We describe the incidence of atypical fractures and their characteristics,
with observational data including a review of the hospital and general
practitioner records. Clinical outcomes were evaluated using the
Harris hip score (HHS) and the timed up-and-go (TUG) test. Atypical fractures only occurred in women with an incidence of
9.8 per 100 000 person-years. The incidence in those who were treated
with bisphosphonates was 79.0 per 100 000 person-years; eight of
17 fractures occurred around metal implants. There was a high incidence
of delayed union and revision surgery. A total of nine patients (ten
AFFs) were available for review at a mean follow-up of 36.5 months
(10 to 104). The clinical outcome was poor with a mean HHS of 58.9
(95% CI 47.4 to 70.4) and a mean TUG test of 25.7 s (95% CI 12.7
to 38.8). The delay in diagnosis and treatment of AFF may result from a
lack of knowledge of this condition. Cite this article: