This study aimed to determine if macrophages can attach and directly affect the oxide layers of 316L stainless steel, titanium alloy (Ti6Al4V), and cobalt-chromium-molybdenum alloy (CoCrMo) by releasing components of these alloys. Murine peritoneal macrophages were cultured and placed on stainless steel, CoCrMo, and Ti6Al4V discs into a 96-well plate. Cells were activated with interferon gamma and lipopolysaccharide. Macrophages on stainless steel discs produced significantly more nitric oxide (NO) compared to their control counterparts after eight to ten days and remained elevated for the duration of the experiment.Aims
Methods
We aimed to determine whether cemented hemiarthroplasty
is associated with a higher post-operative mortality and rate of
re-operation when compared with uncemented hemiarthroplasty. Data
on 19 669 patients, who were treated with a hemiarthroplasty following
a fracture of the hip in a nine-year period from 2002 to 2011, were extracted
from NHS Scotland’s acute admission database (Scottish Morbidity
Record, SMR01). We investigated the rate of mortality at day 0,
1, 7, 30, 120 and one-year post-operatively using 12 case-mix variables
to determine the independent effect of the method of fixation. At
day 0, those with a cemented hemiarthroplasty had a higher rate
of mortality (p <
0.001) compared with those with an uncemented
hemiarthroplasty, equivalent to one extra death per 424 procedures.
By day one this had become one extra death per 338 procedures. Increasing
age and the five-year co-morbidity score were noted as independent
risk factors. By day seven, the cumulative rate of mortality was
less for cemented hemiarthroplasty though this did not reach significance
until day 120. The rate of re-operation was significantly higher
for uncemented hemiarthroplasty. Despite adjusting for 12 confounding
variables, these only accounted for 15% of the observed variability. The debate about the choice of the method of fixation for a hemiarthroplasty
with respect to the rate of mortality or the risk of re-operation
may be largely superfluous. Our results suggest that uncemented
hemiarthroplasties may have a role to play in elderly patients with
significant co-morbid disease. Cite this article:
