Atypical Fracture Cohort Study

Atypical Femur Fracture Ontario Cohort Registry

Osteoporosis is a disease characterized by increased bone fragility and deteriorating bone micro-architecture. The main consequence of osteoporosis is low-trauma fractures, most often of the hip, spine and wrist. Recently, another type of low-trauma fracture, atypical femur fractures (AFFs), have received much attention. Little is known of the cause of these debilitating fractures; however, they have been associated with long term bisphosphonate use. What we currently know about AFFs is based on case reports or small case series, or studies using administrative databases or secondary analyses of bisphosphonate trials. While these reports provide some preliminary information on the relationship between long term bisphosphonate exposure and AFFs, detailed clinical data are absent. As we have established a network of specialists across southern Ontario our group is in a position to collect meaningful information on a larger group of patients who have experienced these debilitating fractures into a centralized AFF registry.

Study Overview

• Status: Recruiting
• Conditions: Atypical Femur Fracture; Atypical Subtrochanteric Fracture; Osteoporosis With AFf

• Study Type: Observational
• Enrollment (Estimated): 300

Contacts and Locations

• Study Contact: Name: Judite Scher, MSc; Phone Number: 416-340-4841; Email: jscher@uhnresearch.ca

Study Locations

• Canada
  • Ontario
    • Hamilton, Ontario, Canada
      • Enrolling by invitation
      • McMaster University
    • Toronto, Ontario, Canada, M5G 2C4
      • Recruiting
      • University Health Network
      • Contact: Phone Number: 416-340-4843; Email: Osteoporosis@uhn.ca
      • Principal Investigator: Angela M Cheung, MD PhD
      • Sub-Investigator: Lianne E Tile, MD Med
      • Sub-Investigator: Rowena Ridout, MD
      • Sub-Investigator: Savannah Cardew, MD
      • Sub-Investigator: Robert Bleakney, MD
      • Sub-Investigator: Christian Veillette, MD
      • Sub-Investigator: Moira Kapral, MD
    • Toronto, Ontario, Canada
      • Enrolling by invitation
      • St Michael's Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 100 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

primary or tertiary care clinic patients who have experienced an atypical fracture at any point in the past will be eligible for this observational study. Low trauma fractures are defined as fractures sustained with minimal force, such as a fall from standing height.

Description

Inclusion Criteria:

• Patients over the age of 20;
• Patients who have experienced an incomplete AFF that satisfies the diagnostic criteria as set forth by the American Society of Bone and mineral Research (ASBMR) International Task Force on AFFs or a low (or no) trauma fracture that mimics the features described above at other sites.

Exclusion Criteria:

• Peri-prosthetic fractures;
• High trauma fractures;
• Pathological fractures secondary to metastases or metabolic bone diseases other than osteoporosis.

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
Atypical femur fracture cohort

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Prospectively identify and diagnose atypical fracture patients in Ontario	The objective of this exploratory study is to identify and diagnose AFF patients	baseline

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Examine risk factors and predictors for AFFs	This exploratory study will examine risk factors and predictors for AFFs	baseline

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Examine how AFFs affect quality of life, functional recovery and health outcomes.	This exploratory study will examine how AFFs affect quality of life, functional recovery and health outcomes over time.	baseline and every 6-12 months

Collaborators and Investigators

• Sponsor: University Health Network, Toronto
• Investigators: Principal Investigator: Angela m Cheung, MD, PhD, University Health Network, Toronto

Study record dates

Study Major Dates

• Study Start: June 1, 2009
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): December 1, 2028

Study Registration Dates

• First Submitted: December 7, 2012
• First Submitted That Met QC Criteria: December 7, 2012
• First Posted (Estimated): December 11, 2012

Study Record Updates

• Last Update Posted (Actual): May 11, 2026
• Last Update Submitted That Met QC Criteria: May 6, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Metabolic Diseases; Wounds and Injuries; Leg Injuries; Musculoskeletal Diseases; Bone Diseases; Hip Injuries; Bone Diseases, Metabolic; Femoral Fractures; Fractures, Bone; Hip Fractures; Osteoporosis
• Other Study ID Numbers: 09-0532

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No