FEMOROPLASTY USING AN INJECTABLE AND RESORBABLE BI-PHOSPHONATE LOADED BONE SUBSTITUTE TO PREVENT CONTRO-LATERAL HIP FRACTURE IN THE ELDERLY: A CADAVERIC BIOMECHANICAL STUDY

Abstract

Introduction: The incidence of contralateral, second hip fractures after a first hip fracture is as high as 20% in the elderly. Femoroplasty using an injectable and resorbable bi-phosphonate loaded bone substitute to prevent controlateral hip fracture may represent a promising preventive therapy. We aimed to evaluate the biomechanical consequences of the femoroplasty using this bone substitute.

Materials and Methods: Twelve paired human cadaveric femora from donors with a mean age of 86 years (7 women and 6 men) were randomly assigned for femoroplasty and biomechanically tested for fracture load against their native contralateral control. Anterior–posterior and lateral radiographs and DXAscan’s were made before injection. Femoroplasty were performed under fluoroscopic guidance with an injectable and resorbable bi-phosphonate loaded bone substitute. All femurs were fractured by simulating a fall on the greater trochanter by an independent observer.

Results: Mean T-score of the tested femur were −3. Bone density was comparable for each pair of femur. All the observed fractures were Kyle II throchanteric fractures. Mean fracture load was 2786 Newton in the femoroplasty group (group F) versus 2116 Newton in the control group (group C) (p< 0.001). Fracture loads were always higher in the group F: mean 41.6% (mini: 1.2%/maxi:102.1%). Effect of femoroplasty was significantly superior for women and also correlated to initial bone density (p< 0.0001).

Discussion:According to our results, femoroplasty with an injectable and resorbable bi-phosphonate loaded bone substitute can provide significant biomechanical reinforcement of the proximal femur to prevent controlateral fracture.