The objective of this study was to characterize the effect of rifampin incorporation into poly(methyl methacrylate) (PMMA) bone cement. While incompatibilities between the two materials have been previously noted, we sought to identify and quantify the cause of rifampin’s effects, including alterations in curing properties, mechanical strength, and residual monomer content. Four cement groups were prepared using commercial PMMA bone cement: a control; one with 1 g of rifampin; and one each with equimolar amounts of ascorbic acid or hydroquinone relative to the amount of rifampin added. The handling properties, setting time, exothermic output, and monomer loss were measured throughout curing. The mechanical strength of each group was tested over 14 days. A radical scavenging assay was used to assess the scavenging abilities of rifampin and its individual moieties.Objectives
Methods
We used a goat model of a contaminated musculoskeletal defect to determine the effectiveness of rapidly-resorbing calcium-sulphate pellets containing amikacin to reduce the local bacterial count. Our findings showed that this treatment eradicated the bacteria quickly, performed as well as standard polymethylmethacrylate mixed with an antibiotic and had many advantages over the latter. The pellets were prepared before surgery and absorbed completely. They released all of the antibiotic and did not require a subsequent operation for their removal. Our study indicated that locally administered antibiotics reduced bacteria within the wound rapidly. This method of treatment may have an important role in decreasing the rate of infection in contaminated wounds.
A common situation presenting to the orthopaedic
surgeon today is a worn acetabular liner with substantial acetabular
and pelvic osteolysis. The surgeon has many options for dealing
with osteolytic defects. These include allograft, calcium based
substitutes, demineralised bone matrix, or combinations of these
options with or without addition of platelet rich plasma. To date
there are no clinical studies to determine the efficacy of using
bone-stimulating materials in osteolytic defects at the time of
revision surgery and there are surprisingly few studies demonstrating
the clinical efficacy of these treatment options. Even when radiographs
appear to demonstrate incorporation of graft material CT studies
have shown that incorporation is incomplete. The surgeon, in choosing
a graft material for a surgical procedure must take into account
the efficacy, safety, cost and convenience of that material. Cite this article:
A total of 20 patients with a depressed fracture
of the lateral tibial plateau (Schatzker II or III) who would undergo open
reduction and internal fixation were randomised to have the metaphyseal
void in the bone filled with either porous titanium granules or
autograft bone. Radiographs were undertaken within one week, after
six weeks, three months, six months, and after 12 months. The primary outcome measure was recurrent depression of the joint
surface: a secondary outcome was the duration of surgery. The risk of recurrent depression of the joint surface was lower
(p <
0.001) and the operating time less (p <
0.002) when titanium
granules were used. The indication is that it is therefore beneficial to use porous
titanium granules than autograft bone to fill the void created by
reducing a depressed fracture of the lateral tibial plateau. There
is no donor site morbidity, the operating time is shorter and the
risk of recurrent depression of the articular surface is less. Cite this article:
Demineralised bone matrix (DBM) is rarely used for the local
delivery of prophylactic antibiotics. Our aim, in this study, was
to show that a graft with a bioactive glass and DBM combination,
which is currently available for clinical use, can be loaded with
tobramycin and release levels of antibiotic greater than the minimum
inhibitory concentration for Antibiotic was loaded into a graft and subsequently evaluated
for drug elution kinetics and the inhibition of bacterial growth.
A rat femoral condylar plug model was used to determine the effect
of the graft, loaded with antibiotic, on bone healing.Aims
Materials and Methods
Bacterial infection in orthopaedic surgery can be devastating, and is associated with significant morbidity and poor functional outcomes, which may be improved if high concentrations of antibiotics can be delivered locally over a prolonged period of time. The two most widely used methods of doing this involve antibiotic-loaded polymethylmethacrylate or collagen fleece. The former is not biodegradable and is a surface upon which secondary bacterial infection may occur. Consequently, it has to be removed once treatment has finished. The latter has been used successfully as an adjunct to systemic antibiotics, but cannot effect a sustained release that would allow it to be used on its own, thereby avoiding systemic toxicity. This review explores the newer biodegradable carrier systems which are currently in the experimental phase of development and which may prove to be more effective in the treatment of osteomyelitis.
This systematic review examines the current literature regarding surgical techniques for restoring articular cartilage in the hip, from the older microfracture techniques involving perforation to the subchondral bone, to adaptations of this technique using nanofractures and scaffolds. This review discusses the autologous and allograft transfer systems and the autologous matrix-induced chondrogenesis (AMIC) technique, as well as a summary of the previously discussed techniques, which could become common practice for restoring articular cartilage, thus reducing the need for total hip arthroplasty. Using the
Recent studies have shown that modulating inflammation-related
lipid signalling after a bone fracture can accelerate healing in
animal models. Specifically, decreasing 5-lipoxygenase (5-LO) activity
during fracture healing increases cyclooxygenase-2 (COX-2) expression
in the fracture callus, accelerates chondrogenesis and decreases
healing time. In this study, we test the hypothesis that 5-LO inhibition
will increase direct osteogenesis. Bilateral, unicortical femoral defects were used in rats to measure
the effects of local 5-LO inhibition on direct osteogenesis. The
defect sites were filled with a polycaprolactone (PCL) scaffold
containing 5-LO inhibitor (A-79175) at three dose levels, scaffold
with drug carrier, or scaffold only. Drug release was assessed Objectives
Methods
The osteoinductive properties of demineralised
bone matrix have been demonstrated in animal studies. However, its therapeutic
efficacy has yet to be proven in humans. The clinical properties
of AlloMatrix, an injectable calcium-based demineralised bone matrix
allograft, were studied in a prospective randomised study of 50
patients with an isolated unstable distal radial fracture treated
by reduction and Kirschner (K-) wire fixation. A total of 24 patients
were randomised to the graft group (13 men and 11 women, mean age
42.3 years (20 to 62)) and 26 to the no graft group (8 men and 18
women, mean age 45.0 years (17 to 69)). At one, three, six and nine weeks, and six and 12 months post-operatively,
patients underwent radiological evaluation, assessments for range
of movement, grip and pinch strength, and also completed the Disabilities
of Arm, Shoulder and Hand questionnaire. At one and six weeks and
one year post-operatively, bone mineral density evaluations of both
wrists were performed. No significant difference in wrist function and speed of recovery,
rate of union, complications or bone mineral density was found between
the two groups. The operating time was significantly higher in the
graft group (p = 0.004). Radiologically, the reduction parameters
remained similar in the two groups and all AlloMatrix extraosseous leakages
disappeared after nine weeks. This prospective randomised controlled trial did not demonstrate
a beneficial effect of AlloMatrix demineralised bone matrix in the
treatment of this category of distal radial fractures treated by
K-wire fixation. Cite this article:
Many aspects of the surgical treatment of patients with tuberculosis
(TB) of the spine, including the use of instrumentation and the
types of graft, remain controversial. Our aim was to report the
outcome of a single-stage posterior procedure, with or without posterior
decompression, in this group of patients. Between 2001 and 2010, 51 patients with a mean age of 62.5 years
(39 to 86) underwent long posterior instrumentation and short posterior
or posterolateral fusion for TB of the thoracic and lumbar spines,
followed by anti-TB chemotherapy for 12 months. No anterior debridement
of the necrotic tissue was undertaken. Posterior decompression with
laminectomy was carried out for the 30 patients with a neurological
deficit.Aim
Patients and Methods
To explore the therapeutic potential of combining bone marrow-derived mesenchymal stem cells (BM-MSCs) and hydroxyapatite (HA) granules to treat nonunion of the long bone. Ten patients with an atrophic nonunion of a long bone fracture were selectively divided into two groups. Five subjects in the treatment group were treated with the combination of 15 million autologous BM-MSCs, 5g/cm3 (HA) granules and internal fixation. Control subjects were treated with iliac crest autograft, 5g/cm3 HA granules and internal fixation. The outcomes measured were post-operative pain (visual analogue scale), level of functionality (LEFS and DASH), and radiograph assessment.Objectives
Methods
Systemic antibiotics reduce infection in open
fractures. Local delivery of antibiotics can provide higher doses
to wounds without toxic systemic effects. This study investigated
the effect on infection of combining systemic with local antibiotics
via polymethylmethacrylate (PMMA) beads or gel delivery. An established Combined local and systemic antibiotics were superior to systemic
antibiotics alone at reducing the quantity of bacteria recoverable
from each group (p = 0.002 for gel; p = 0.032 for beads). There
was no difference in the bacterial counts between bead and gel delivery
(p = 0.62). These results suggest that local antibiotics augment the antimicrobial
effect of systemic antibiotics. Although no significant difference
was found between vehicles, gel delivery offers technical advantages
with its biodegradable nature, ability to conform to wound shape
and to deliver increased doses. Further study is required to see
if the gel delivery system has a clinical role. Cite this article:
The number of arthroplasties being undertaken
is expected to grow year on year, and periprosthetic joint infections will
be an increasing socioeconomic burden. The challenge to prevent
and eradicate these infections has resulted in the emergence of
several new strategies, which are discussed in this review. Cite this article:
We evaluated radiological hip remodelling after shelf acetabuloplasty and sought to identify prognostic factors in 25 patients with a mean age of 8.9 years (7.0 to 12.3) who had unilateral Perthes’ disease with reducible subluxation of the hip in the fragmentation stage. At a mean follow-up of 6.7 years (3.2 to 9.0), satisfactory remodelling was observed in 18 hips (72%). The type of labrum in hip abduction, as determined by intra-operative dynamic arthrography, was found to be a statistically significant prognostic factor (p = 0.012). Shelf acetabuloplasty as containment surgery seems to be best indicated for hips in which there is not marked collapse of the epiphysis and in which the extruded epiphyseal segment slips easily underneath the labrum on abduction, without imposing undue pressure on the lateral edge of the acetabulum.
Between 1999 and 2005, 23 failed total ankle replacements were converted to arthrodeses. Three surgical techniques were used: tibiotalar arthrodesis with screw fixation, tibiotalocalcaneal arthrodesis with screw fixation, and tibiotalocalcaneal arthrodesis with an intramedullary nail. As experience was gained, the benefits and problems became apparent. Successful bony union was seen in 17 of the 23 ankles. The complication rate was higher in ankles where the loosening had caused extensive destruction of the body of the talus, usually in rheumatoid arthritis. In this situation we recommend tibiotalocalcaneal arthrodesis with an intramedullary nail. This technique can also be used when there is severe arthritic change in the subtalar joint. Arthrodesis of the tibiotalar joint alone using compression screws was generally possible in osteoarthritis because the destruction of the body of the talus was less extensive. Tibiotalocalcaneal arthrodesis fusion with compression screws has not been successful in our experience.
The August 2014 Research Roundup360 looks at: Antibiotic loaded ceramic of use in osteomyelitis; fibronectin implicated in cartilage degeneration; Zinc Chloride accelerates fracture healing in rats; advertisements and false claims; Net Promoter Score: substance or rhetoric?; aspirin for venous thromboembolism prophylaxis and dissection, stress and the soul.
Intramedullary infection in long bones represents
a complex clinical challenge, with an increasing incidence due to the
increasing use of intramedullary fixation. We report a prospective
case series using an intramedullary reaming device, the Reamer–Irrigator–Aspirator
(RIA) system, in association with antibiotic cement rods for the
treatment of lower limb long bone infections. A total of 24 such
patients, 16 men and eight women, with a mean age of 44.5 years
(17 to 75), 14 with femoral and 10 with tibial infection, were treated
in a staged manner over a period of 2.5 years in a single referral
centre. Of these, 21 patients had had previous surgery, usually
for fixation of a fracture (seven had sustained an open fracture
originally and one had undergone fasciotomies). According to the
Cierny–Mader classification system, 18 patients were classified
as type 1A, four as 3A (discharging sinus tract), one as type 4A
and one as type 1B. Cite this article:
Articular cartilage repair remains a challenge to surgeons and basic scientists. The field of tissue engineering allows the simultaneous use of material scaffolds, cells and signalling molecules to attempt to modulate the regenerative tissue. This review summarises the research that has been undertaken to date using this approach, with a particular emphasis on those techniques that have been introduced into clinical practice, via in vitro and preclinical studies.
The need for bone tissue supplementation exists in a wide range
of clinical conditions involving surgical reconstruction in limbs,
the spine and skull. The bone supplementation materials currently
used include autografts, allografts and inorganic matrix components;
but these pose potentially serious side-effects. In particular the
availability of the autografts is usually limited and their harvesting
causes surgical morbidity. Therefore for the purpose of supplementation
of autologous bone graft, we have developed a method for autologous
extracorporeal bone generation. Human osteoblast-like cells were seeded on porous granules of
tricalcium phosphate and incubated in osteogenic media while exposed
to mechanical stimulation by vibration in the infrasonic range of
frequencies. The generated tissue was examined microscopically following
haematoxylin eosin, trichrome and immunohistochemical staining.Objectives
Methods