Download Date: Dear Dr. Your patient was seen as part of our Fracture Liaison

Date:____________________
Dear Dr. __________________________
Your patient was seen as part of our Fracture Liaison Service Program, having presented with a femoral
fracture due to a simple fall or low impact trauma. Upon further assessment, this fracture was
determined to be a subtrochanteric/femoral shaft fracture which falls outside the scope of our Program.
As the assessment of such fractures is complicated, we have referred your patient to Dr. _________
(local osteoporosis specialist).
The information below is derived from the American Society of Bone and Mineral Research Task Force
on Atypical Femoral Fractures and is provided to you for your information.
There are two types of subtrochanteric/femoral shaft fragility fractures: true osteoporotic fractures and
atypical femoral fractures. The following characteristics may help differentiate between the two.
Frequency
Cause
Prodromal
symptoms
Mechanism of
injury
X-ray findings
True osteoporotic fracture
Atypical femoral fracture
Infrequent: 10% of all femoral
fractures
In 70-90% of these cases, this is due
to undiagnosed/untreated
osteoporosis. A minority of patients
will have been on osteoporosis
medication (in which case, this may
represent failure or relative failure of
treatment).
There is no prodromal leg/groin pain.
Common arthritic complaints may be
a confounder.
A fall occurred that lead to the
fracture (the bone breaks once it hits
the ground).
Comminuted or spiral.
Rare: less than 1% of all femoral fractures. Only 25% of
subtrochanteric/femoral shaft fractures are atypical.
90% will have had exposure to osteoporosis
medications. Atypical femoral fractures have been
reported with all bisphosphonates and with
denosumab, usually after prolonged exposure (greater
than 5 years).
Patients with typical osteoporotic
Osteoporosis
fractures are at HIGH RISK for
management
considerations repeat fractures and should be
continued on an appropriate
osteoporosis medication (although a
review/consideration of changing
the agent may be warranted).
70% will have experienced prodromal pain in the thigh
or groin (for weeks/months prior to fracture).
Minimal or no trauma. The patient may describe that
the leg let go or bone snapped/cracked BEFORE the fall
occurred
Non-comminuted. It has transverse or short oblique
configuration, with a medial spike. There may also be
cortical thickening of the lateral cortex at the site of the
fracture.
The medical management of atypical femoral fractures
is complicated as there is a need to balance the risks of
continuing treatment (risk of developing a
contralateral atypical femoral fracture) vs. the risks of
discontinuing treatment (risk of suffering any of the
many other types of classic osteoporotic fractures).
Such patients would benefit from referral to an
osteoporosis specialist to help determine the best
course of treatment.
We hope this information will prove useful in guiding the management of your patient.
Sincerely,
Nurse Smith, NP
FLS Coordinator
Dr. White, MD FRCPC/FRCSC
FLS Medical Director, Orthopaedic Surgeon or Local opinion leader