Periprosthetic femoral fractures around hip replacements are increasingly
common. When the femoral component is stable, open reduction and
internal fixation is recommended in all but exceptional cases. The
purpose of this study was to evaluate the outcome of treatment of
fractures around stable implants with cortical onlay strut allografts
with or without a plate.
A survey of our four centers identified forty patients with a fracture
around a well-fixed femoral stem treated with cortical onlay strut
allografts without revision of the femoral component. There were
fourteen men and twenty-six women, with an average age of sixty-nine
years. Nineteen patients were treated with cortical onlay strut
allografts alone, and twenty-one were managed with a plate and one
or two cortical struts. All of the patients were followed until
fracture union or until a reoperation was done. The mean duration
of follow-up was twenty-eight months for thirty-nine patients. One
patient, who was noncompliant with treatment recommendations, had
a failure at two months because of a fracture of the plate and graft.
The primary end point of the evaluation was fracture union; secondary
end points included strut-to-host bone union, the amount of final
bone stock, and postoperative function.
Thirty-nine (98%) of the forty fractures united, and strut-to-host
bone union was typically seen within the first year. There were
four malunions, all of which had <10° of malalignment,
and one deep infection. There was no evidence of femoral loosening
in any patient. All but one of the surviving patients returned to
their preoperative functional level within one year.
Cortical onlay strut allografts act as biological bone plates, serving
both a mechanical and a biological function. The use of cortical
struts, either alone or in conjunction with a plate, led to a very
high rate of fracture union, satisfactory alignment, and an increase
in femoral bone stock at the time of short-term follow-up. Although
this study did not address the potential for later allograft remodeling,
our findings suggest that cortical strut grafts should be used routinely
to augment fixation and healing of a periprosthetic femoral fracture.