Articular cartilage has very poor repair potential, however it has an extraordinary capacity to withstand physiological mechanical loads in an intact joint. The nature and extent of chondrocyte death in articular cartilage following many forms of injury (trephine, scalpel, osteotome, sutures and drilling) has been characterised, but the ability to bear mechanical injury from iatrogenic surgical interventions is still unknown. A standard arthroscopic probe was moved at varying physiological pressures along the articular cartilage of joint before staining with fluorescent dyes to allow live/dead cell imaging using laser confocal scanning microscopy and imaging software, Image J.
In some centres, serial bedside aspirations, in association with intravenous antibiotics, are still an accepted treatment for septic arthritis (Mathews, Postgraduate Medical Journal, 2008). However, there is a risk that bacterial products remain in the joint, even when the bacteria have been destroyed. We have conducted a study to ascertain whether bacterial products alone have an effect on in situ chondrocyte viability. A hip aspirate (25μl), containing Staphylococcus aureus, from a patient with septic arthritis was added to 5ml culture medium and incubated (37°C) for 48hrs. The solution was then centrifuged (3400g for 10mins) and the supernatant removed. Cartilage explants were harvested from a
We investigated the static and cyclical strength of parallel and angulated locking plate screws using rigid polyurethane foam (0.32 g/cm. 3. ) and
Introduction. Patients suffering from finger joint pain or dysfunction due to arthritis and traumatic injury may require arthroplasty and joint replacement. Single-part silicone-based implants remain the material of choice and most widely used option, although reports on their long-term clinical performance are variable. For trauma indications, patients have a high expectation of functionality necessitating the use of materials with high wear resistance and mechanical performance. A new proximal inter phalangeal (PIP) joint designed by Zrinski AG (Wurmlingen, Germany), comprising a self-mating carbon fibre reinforced polyetheretherketone (CFR-PEEK) coupling, may provide a suitable alternative. Here we describe the wear performance of the CFR-PEEK components in a PIP joint wear simulator and subsequent characterisation of the wear particles. Methods. Four proximal and distal PIP components were milled (Zrinski AG) from CFR-PEEK (Invibio Ltd, UK) and subjected to wear testing (Endo Lab ® GmbH, Germany). The test was conducted at 37°C over 5 million cycles in 25%
The purpose of this study was to: review the efficacy of the induced membrane technique (IMT), also known as the Masquelet technique; and investigate the relationship between patient factors and technique variations on the outcomes of the IMT. A systematic search was performed in CINAHL, The Cochrane Library, Embase, Ovid MEDLINE, and PubMed. We included articles from 1 January 1980 to 30 September 2019. Studies with a minimum sample size of five cases, where the IMT was performed primarily in adult patients (≥ 18 years old), in a long bone were included. Multivariate regression models were performed on patient-level data to determine variables associated with nonunion, postoperative infection, and the need for additional procedures.Aims
Methods
We report the outcome of 84 nonunions involving
long bones which were treated with rhBMP-7, in 84 patients (60 men:
24 women) with a mean age 46 years (18 to 81) between 2003 and 2011.
The patients had undergone a mean of three previous operations (one
to 11) for nonunion which had been present for a mean of 17 months
(4 months to 20 years). The nonunions involved the lower limb in
71 patients and the remainder involved the upper limb. A total of 30
nonunions were septic. Treatment was considered successful when
the nonunion healed without additional procedures. The relationship
between successful union and the time to union was investigated
and various factors including age and gender, the nature of the
nonunion (location, size, type, chronicity, previous procedures,
infection, the condition of the soft tissues) and type of index
procedure (revision of fixation, type of graft, amount of rhBMP-7) were
analysed. The improvement of the patients’ quality of life was estimated
using the Short Form (SF) 12 score. A total of 68 nonunions (80.9%) healed with no need for further
procedures at a mean of 5.4 months (3 to 10) post-operatively. Multivariate
logistic regression analysis of the factors affecting union suggested
that only infection significantly affected the rate of union
(p = 0.004).Time to union was only affected by the number of previous
failed procedures
(p = 0.006). An improvement of 79% and 32.2% in SF-12 physical and
mental score, respectively, was noted within the first post-operative
year. Rh-BMP-7 combined with bone grafts, enabled healing of the nonunion
and improved quality of life in about 80% of patients. Aseptic nonunions
were much more likely to unite than septic ones. The number of previous
failed operations significantly delayed the time to union. Cite this article:
The biomembrane (induced membrane) formed around polymethylmethacrylate (PMMA) spacers has value in clinical applications for bone defect reconstruction. Few studies have evaluated its cellular, molecular or stem cell features. Our objective was to characterise induced membrane morphology, molecular features and osteogenic stem cell characteristics. Following Institutional Review Board approval, biomembrane specimens were obtained from 12 patient surgeries for management of segmental bony defects (mean patient age 40.7 years, standard deviation 14.4). Biomembranes from nine tibias and three femurs were processed for morphologic, molecular or stem cell analyses. Gene expression was determined using the Affymetrix GeneChip Operating Software (GCOS). Molecular analyses compared biomembrane gene expression patterns with a mineralising osteoblast culture, and gene expression in specimens with longer spacer duration (> 12 weeks) with specimens with shorter durations. Statistical analyses used the unpaired student Objectives
Methods
We hypothesised that cells obtained via a Reamer–Irrigator–Aspirator
(RIA) system retain substantial osteogenic potential and are at
least equivalent to graft harvested from the iliac crest. Graft
was harvested using the RIA in 25 patients (mean age 37.6 years
(18 to 68)) and from the iliac crest in 21 patients (mean age 44.6
years (24 to 78)), after which ≥ 1 g of bony particulate graft material
was processed from each. Initial cell viability was assessed using Trypan
blue exclusion, and initial fluorescence-activated cell sorting
(FACS) analysis for cell lineage was performed. After culturing
the cells, repeat FACS analysis for cell lineage was performed and
enzyme-linked immunosorbent assay (ELISA) for osteocalcin, and Alizarin
red staining to determine osteogenic potential. Cells obtained via
RIA or from the iliac crest were viable and matured into mesenchymal
stem cells, as shown by staining for the specific mesenchymal antigens
CD90 and CD105. For samples from both RIA and the iliac crest there
was a statistically significant increase in bone production (both
p <
0.001), as demonstrated by osteocalcin production after induction. Medullary autograft cells harvested using RIA are viable and
osteogenic. Cell viability and osteogenic potential were similar
between bone grafts obtained from both the RIA system and the iliac
crest. Cite this article:
We reviewed 59 bone graft substitutes marketed
by 17 companies currently available for implantation in the United Kingdom,
with the aim of assessing the peer-reviewed literature to facilitate
informed decision-making regarding their use in clinical practice.
After critical analysis of the literature, only 22 products (37%)
had any clinical data. Norian SRS (Synthes), Vitoss (Orthovita),
Cortoss (Orthovita) and Alpha-BSM (Etex) had Level I evidence. We question
the need for so many different products, especially with limited
published clinical evidence for their efficacy, and conclude that
there is a considerable need for further prospective randomised
trials to facilitate informed decision-making with regard to the
use of current and future bone graft substitutes in clinical practice. Cite this article:
Most animal studies indicate that early irrigation
and debridement reduce infection after an open fracture. Unfortunately,
these studies often do not involve antibiotics. Clinical studies
indicate that the timing of initial debridement does not affect
the rate of infection but these studies are observational and fraught
with confounding variables. The purpose of this study was to control
these variables using an animal model incorporating systemic antibiotics
and surgical treatment. We used a rat femur model with a defect which was contaminated
with No animal that received antibiotics and surgery two hours after
injury had detectable bacteria. When antibiotics were started at
two hours, a delay in surgical treatment from two to six hours significantly
increased the development of infection (p = 0.047). However, delaying
surgery to 24 hours increase the rate of infection, but not significantly
(p = 0.054). The timing of antibiotics had a more significant effect
on the proportion of positive samples than earlier surgery. Delaying
antibiotics to six or 24 hours had a profoundly detrimental effect
on the infection rate regardless of the timing of surgery. These
findings are consistent with the concept that bacteria progress
from a vulnerable planktonic form to a treatment-resistant biofilm.