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:
Cite this article:
The importance for observing the intention-to-treat
approach in clinical studies is explained. Cite this article:
Peri-prosthetic fracture after joint replacement in the lower limb is associated with significant morbidity. The primary aim of this study was to investigate the incidence of peri-prosthetic fracture after total hip replacement (THR) and total knee replacement (TKR) over a ten-year period using a population-based linked dataset. Between 1 April 1997 and 31 March 2008, 52 136 primary THRs, 8726 revision THRs, 44 511 primary TKRs, and 3222 revision TKRs were performed. Five years post-operatively, the rate of fracture was 0.9% after primary THR, 4.2% after revision THR, 0.6% after primary TKR and 1.7% after revision TKR. Comparison of survival analysis for all primary and revision arthroplasties showed peri-prosthetic fractures were more likely in females, patients aged >
70 and after revision arthroplasty. Female patients aged >
70 should be warned of a significantly increased risk of peri-prosthetic fracture after hip or knee replacement. The use of adjuvant medical treatment to reduce the effect of peri-prosthetic osteoporosis may be a direction of research for these patients.
We investigated the excess mortality risk associated with fractures of the hip. Data related to 29 134 patients who underwent surgery following a fracture of the hip were obtained from the Scottish Hip Fracture Audit database. Fractures due to primary or metastatic malignancy were excluded. An independent database (General Register Office (Scotland)) was used to validate dates of death. The observed deaths per 100 000 of the population were then calculated for each group (gender, age and fracture type) at various time intervals up to eight years. A second database (Interim Life Tables for Scotland, Scottish Government) was then used to create standardised mortality ratios. Analysis showed that mortality in patients aged >
85 years with a fracture of the hip tended to return to the level of the background population between two and five years after the fracture. In those patients aged <
85 years excess mortality associated with hip fracture persisted beyond eight years. Extracapsular hip fractures and male gender also conferred increased risk.
We have investigated how medical postponement, the time to surgery and the correction of medical abnormalities, according to McLaughlin criteria, before operation affected peri-operative mortality after fracture of the hip. From February to December 2007, in addition to core data, the Scottish Hip Fracture Audit collected information relating to surgical delay. Data were available for 4284 patients which allowed 30-day survival analysis to be performed. Multivariable logistic regression models were used to control for differences in case-mix. Patients with major clinical abnormalities were more likely to have a postponement and had a lower unadjusted 30-day survival. The time to operation and postponement were not associated with higher mortality after adjustment for case-mix. Correction of major clinical abnormalities before surgery improved the adjusted survival, but this improvement was not significant (p = 0.10). Postponement without correction of a medical abnormality before surgery was associated with a significantly lower (p = 0.006) 30-day adjusted survival. The possible benefits of postponement need to be weighed against prolonged discomfort for the patient and the possibility of the development of other complications.
We investigated the relationship between a number of patient and management variables and mortality after surgery for fracture of the hip. Data relating to 18 817 patients were obtained from the Scottish Hip Fracture Audit database. We divided variables into two categories, depending on whether they were case-mix (age; gender; fracture type; pre-fracture residence; pre-fracture mobility and ASA scores) or management variables (time from fracture to surgery; time from admission to surgery; grade of surgical and anaesthetic staff undertaking the procedure and anaesthetic technique). Multivariate logistic regression analysis showed that all case-mix variables were strongly associated with post-operative mortality, even when controlling for the effects of the remaining variables. Inclusion of the management variables into the case-mix base regression model provided no significant improvement to the model. Patient case-mix variables have the most significant effect on post-operative mortality and unfortunately such variables cannot be modified by pre-operative medical interventions.
We report gender differences in the epidemiology and outcome after hip fracture from the Scottish Hip Fracture Audit, with data on admission and at 120 days follow-up from 22 orthopaedic units across the country between 1998 and 2005. Outcome measures included early mortality, length of hospital stay, 120-day residence and mobility. A multivariate logistic regression model compared outcomes between genders. The study comprised 25 649 patients of whom 5674 (22%) were men and 19 975 (78%) were women. The men were in poorer pre-operative health, despite being younger at presentation (mean 77 years (60 to 101) Multivariate analysis indicated that the men were less likely to return to their home or mobilise independently at the 120-day follow-up. Mortality at 30 and 120 days was higher for men, even after differences in case-mix variables between genders were considered.
The application and interpretation of the impact factor of a journal is fraught with problems, some of which are explored in this editorial.
A consecutive series of 23 patients (25 ankles) with osteoarthritis of the ankle and severe varus or valgus deformity were treated by open arthrodesis using compression screws. Primary union was achieved in 24 ankles one required further surgery to obtain a solid fusion. The high level of satisfaction in this group of patients reinforces the view that open arthrodesis, as opposed to ankle replacement or arthroscopic arthrodesis, continues to be the treatment of choice when there is severe varus or valgus deformity associated with the arthritis.
The clinical features, investigation, treatment and outcome of two adults with fibrogenesis imperfecta ossium are described. In this rare acquired disorder of bone, normal lamellar collagen is replaced by structurally unsound collagen-deficient tissue, which leads to extreme bone fragility and ununited fractures. Transmission microscopy and SEM showed striking ultrastructural changes in bone structure and mineralisation. Both patients had monoclonal IgG paraproteins in the plasma and one excreted monoclonal lambda light chains in the urine. No abnormal plasma cells were found in the bone marrow and there was no evidence of amyloid deposition in the tissues. In both patients initial treatment with 1 alpha-hydroxycholecalciferol appeared to be ineffective, but in one, repeated courses of melphalan and corticosteroids over three years together with 1 alpha-hydroxycholecalciferol produced striking clinical and histological improvement. The findings in these and other patients strongly suggest that paraproteinaemia is an integral feature of fibrogenesis imperfecta ossium, and this needs further investigation.