The processes linking long-term bisphosphonate treatment to atypical fracture remain elusive. To establish a means of exploring this link, we have examined how long-term bisphosphonate treatment with prior ovariectomy modifies femur fracture behaviour and tibia mass and shape in murine bones. Three groups (seven per group) of 12-week-old mice were: 1) ovariectomized and 20 weeks thereafter treated weekly for 24 weeks with 100 μm/kg subcutaneous ibandronate (OVX+IBN); 2) ovariectomized (OVX); or 3) sham-operated (SHAM). Quantitative fracture analysis generated biomechanical properties for the femoral neck. Tibiae were microCT scanned and trabecular (proximal metaphysis) and cortical parameters along almost its whole length measured.Aims
Methods
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: