, Volume 89, Issue 6, pp 427-433,
Open Access This content is freely available online to anyone, anywhere at any time.
Date: 30 Oct 2011

Subtrochanteric Fractures in Bisphosphonate-Naive Patients: Results from the HORIZON-Recurrent Fracture Trial

Abstract

Our purpose was to characterize the risks of osteoporosis-related subtrochanteric fractures in bisphosphonate-naive individuals. Baseline characteristics of patients enrolled in the HORIZON-Recurrent Fracture Trial with a study-qualifying hip fracture were examined, comparing those who sustained incident subtrochanteric fractures with those sustaining other hip fractures. Subjects were bisphosphonate-naive or had a bisphosphonate washout period of 6–24 months and subsequently received an annual infusion of zoledronic acid 5 mg or placebo after low-trauma hip-fracture repair. In total, 2,127 men and women were included. Of the qualifying hip fractures, 5.2% were subtrochanteric, 54.8% femoral neck, 33.0% intertrochanteric, and 7.1% other (generally complex fractures of mixed type). Significant baseline (pre-hip fracture) differences were seen between index hip-fracture types, with the percentage of patients with extreme mobility problems being twofold higher in patients with index subtrochanteric fracture (9.9%) compared to other patients. The distribution of hip-fracture types was similar between the treatment groups at baseline. No patients with index subtrochanteric fractures and six patients with other qualifying hip fractures reported prior bisphosphonate use. Only one further subtrochanteric fracture occurred in each treatment group over an average 2-year patient follow-up. Subtrochanteric fractures are not uncommon in bisphosphonate-naive patients. Extreme difficulties with mobility may be a unique risk factor predisposing to development of incident subtrochanteric fractures rather than other types of hip fracture. In patients with recent hip fracture who received zoledronic acid therapy, the incidence of new subtrochanteric fractures was too small to draw any meaningful conclusions.

This study is conducted on behalf of the HORIZON-Recurrent Fracture Trial.
Adachi has received research funding and consulting fees from Amgen, Bristol-Myers Squibb, Eli Lilly, GSK, Merck, Novartis, Nycomed, Pfizer, Procter & Gamble, Roche, sanofi-aventis, Servier, Wyeth, and Warner Chilcott. Lyles has received research funding from Amgen, Novartis and Alliance for Better Bone Health, and consulting fees from Amgen, Novartis, Procter & Gamble, Merck, Kirin Pharmaceutical, GTx, Lilly, GSK, Bone Medical Ltd., Wyeth, and Osteologix. He is inventor of US Patent Application: ‘Medication kits and formulations for preventing, treating or reducing secondary fractures after previous fracture’, Number 12532285. He is co-inventor of US Patent Application: ‘Methods for preventing or reducing secondary fractures after hip fracture’, Number 20050272707, and of US Provisional Patent Application: ‘Bisphosphonates and heart disease’. Boonen has received research funding and consulting fees from Novartis. Colón-Emeric has received research funding from Pfizer and Novartis, and consulting fees from Amgen and Novartis. Hyldstrup has received research funding from Eli Lilly, Nycomed, Pfizer and Novo Nordisk and consulting fees from Novartis, Amgen, Eli Lilly, Nycomed, Roche and GSK. Nordsletten has received research funding and consulting fees from Amgen, Novartis, DePuy, Stryker, and Biomet. Pieper has received consulting fees from Novartis. Recknor has received consulting fees from Eli Lilly, Dramatic Health, Novartis, Takeda and Zelos, and lecture fees from Amgen, Novartis and Publicis Meetings. Su is an employee of Novartis. Bucci-Rechtweg is an employee of Novartis and owns stock in the company. Magaziner has received research funding from Eli Lilly, Merck, and Novartis. He has consulted with or served on an advisory board for Amgen, Eli Lilly, GSK, Novartis, and sanofi-aventis.