Tuberculosis (TB) infection of bones and joints accounts for
6.7% of TB cases in England, and is associated with significant
morbidity and disability. Public Health England reports that patients
with TB experience delays in diagnosis and treatment. Our aims were
to determine the demographics, presentation and investigation of
patients with a TB infection of bones and joints, to help doctors
assessing potential cases and to identify avoidable delays. This was a retrospective observational study of all adults with
positive TB cultures on specimens taken at a tertiary orthopaedic
centre between June 2012 and May 2014. A laboratory information
system search identified the patients. The demographics, clinical presentation,
radiology, histopathology and key clinical dates were obtained from
medical records.Aims
Patients and Methods
Patient-specific (PS) implantation surgical technology has been introduced in recent years and a gradual increase in the associated number of surgical cases has been observed. PS technology uses a patient’s own geometry in designing a medical device to provide minimal bone resection with improvement in the prosthetic bone coverage. However, whether PS unicompartmental knee arthroplasty (UKA) provides a better biomechanical effect than standard off-the-shelf prostheses for UKA has not yet been determined, and still remains controversial in both biomechanical and clinical fields. Therefore, the aim of this study was to compare the biomechanical effect between PS and standard off-the-shelf prostheses for UKA. The contact stresses on the polyethylene (PE) insert, articular cartilage and lateral meniscus were evaluated in PS and standard off-the-shelf prostheses for UKA using a validated finite element model. Gait cycle loading was applied to evaluate the biomechanical effect in the PS and standard UKAs.Objectives
Methods
Malrotation of the femoral component can result in post-operative complications in total knee arthroplasty (TKA), including patellar maltracking. Therefore, we used computational simulation to investigate the influence of femoral malrotation on contact stresses on the polyethylene (PE) insert and on the patellar button as well as on the forces on the collateral ligaments. Validated finite element (FE) models, for internal and external malrotations from 0° to 10° with regard to the neutral position, were developed to evaluate the effect of malrotation on the femoral component in TKA. Femoral malrotation in TKA on the knee joint was simulated in walking stance-phase gait and squat loading conditions.Objectives
Materials and Methods
The exact aetiology and pathogenesis of microdamage-induced long bone fractures remain unknown. These fractures are likely to be the result of inadequate bone remodelling in response to damage. This study aims to identify an association of osteocyte apoptosis, the presence of osteocytic osteolysis, and any alterations in sclerostin expression with a fracture of the third metacarpal (Mc-III) bone of Thoroughbred racehorses. A total of 30 Mc-III bones were obtained; ten bones were fractured during racing, ten were from the contralateral limb, and ten were from control horses. Each Mc-III bone was divided into a fracture site, condyle, condylar groove, and sagittal ridge. Microcracks and diffuse microdamage were quantified. Apoptotic osteocytes were measured using TUNEL staining. Cathepsin K, matrix metalloproteinase-13 (MMP-13), HtrA1, and sclerostin expression were analyzed.Objectives
Methods
Posterior condylar offset (PCO) and posterior tibial slope (PTS) are critical factors in total knee arthroplasty (TKA). A computational simulation was performed to evaluate the biomechanical effect of PCO and PTS on cruciate retaining TKA. We generated a subject-specific computational model followed by the development of ± 1 mm, ± 2 mm and ± 3 mm PCO models in the posterior direction, and -3°, 0°, 3° and 6° PTS models with each of the PCO models. Using a validated finite element (FE) model, we investigated the influence of the changes in PCO and PTS on the contact stress in the patellar button and the forces on the posterior cruciate ligament (PCL), patellar tendon and quadriceps muscles under the deep knee-bend loading conditions.Objectives
Methods
Studies reporting specifically on squeaking in total hip arthroplasty have focused on cementless, and not on hybrid, fixation. We hypothesised that the cement mantle of the femur might have a damping effect on the sound transmitted through the metal stem. The objective of this study was to test the effect of cement on sound propagation along different stem designs and under different fixation conditions. An Objectives
Methods
To investigate the bone penetration of intravenous antibiotic
prophylaxis with flucloxacillin and gentamicin during hip and knee
arthroplasty, and their efficacy against Bone samples from the femoral head, neck and acetabulum were
collected from 18 patients undergoing total hip arthroplasty (THA)
and from the femur and tibia in 21 patients during total knee arthroplasty
(TKA). The concentration of both antibiotics in the samples was
analysed using high performance liquid chromatography. Penetration
was expressed as a percentage of venous blood concentration. The
efficacy against common infecting organisms was measured against
both the minimum inhibitory concentration 50, and the more stringent epidemiological
cutoff value for resistance (ECOFF).Aims
Patients and Methods
The surface of pure titanium (Ti) shows decreased histocompatibility over time; this phenomenon is known as biological ageing. UV irradiation enables the reversal of biological ageing through photofunctionalisation, a physicochemical alteration of the titanium surface. Ti implants are sterilised by UV irradiation in dental surgery. However, orthopaedic biomaterials are usually composed of the alloy Ti6Al4V, for which the antibacterial effects of UV irradiation are unconfirmed. Here we evaluated the bactericidal and antimicrobial effects of treating Ti and Ti6Al4V with UV irradiation of a lower and briefer dose than previously reported, for applications in implant surgery. Ti and Ti6Al4V disks were prepared. To evaluate the bactericidal effect of UV irradiation, Objectives
Materials and Methods
The aim of this study was to identify the incidence of positive
cultures during the second stage of a two-stage revision arthroplasty
and to analyse the association between positive cultures and an
infection-free outcome. This single-centre retrospective review of prospectively collected
data included patients with a periprosthetic joint infection (PJI)
of either the hip or the knee between 2013 and 2015, who were treated
using a standardised diagnostic and therapeutic algorithm with two-stage
exchange. Failure of treatment was assessed according to a definition
determined by a Delphi-based consensus. Logistic regression analysis
was performed to assess the predictors of positive culture and risk
factors for failure. The mean follow-up was 33 months (24 to 48).Aims
Patients and Methods
The monitoring of fracture healing is a complex process. Typically, successive radiographs are performed and an emerging calcification of the fracture area is evaluated. The aim of this study was to investigate whether different bone healing patterns can be distinguished using a telemetric instrumented femoral internal plate fixator. An electronic telemetric system was developed to assess bone healing mechanically. The system consists of a telemetry module which is applied to an internal locking plate fixator, an external reader device, a sensor for measuring externally applied load and a laptop computer with processing software. By correlation between externally applied load and load measured in the implant, the elasticity of the osteosynthesis is calculated. The elasticity decreases with ongoing consolidation of a fracture or nonunion and is an appropriate parameter for the course of bone healing. At our centre, clinical application has been performed in 56 patients suffering nonunion or fracture of the femur.Objectives
Materials and Methods
Tantalum (Ta) trabecular metal components are increasingly used
to reconstruct major bone defects in revision arthroplasty surgery.
It is known that some metals such as silver have antibacterial properties.
Recent reports have raised the question regarding whether Ta components
are protective against infection in revision surgery. This laboratory
study aimed to establish whether Ta has intrinsic antibacterial
properties against planktonic bacteria, or the ability to inhibit
biofilm formation. Equal-sized pieces of Ta and titanium (Ti) acetabular components
were sterilised and incubated with a low dose inoculum of either Aims
Materials and Methods
Nerve palsy is a well-described complication
following total hip arthroplasty, but is highly distressing and
disabling. A nerve palsy may cause difficulty with the post-operative
rehabilitation, and overall mobility of the patient. Nerve palsy
may result from compression and tension to the affected nerve(s)
during the course of the operation via surgical manipulation and
retractor placement, tension from limb lengthening or compression
from post-operative hematoma. In the literature, hip dysplasia,
lengthening of the leg, the use of an uncemented femoral component, and
female gender are associated with a greater risk of nerve palsy.
We examined our experience at a high-volume, tertiary care referral
centre, and found an overall incidence of 0.3% out of 39 056 primary
hip arthroplasties. Risk factors found to be associated with the
incidence of nerve palsy at our institution included the presence
of spinal stenosis or lumbar disc disease, age younger than 50,
and smoking. If a nerve palsy is diagnosed, imaging is mandatory
and surgical evacuation or compressive haematomas may be beneficial.
As palsies are slow to recover, supportive care such as bracing,
therapy, and reassurance are the mainstays of treatment. Cite this article:
In the present study, we aimed to assess whether gelatin/β-tricalcium phosphate (β-TCP) composite porous scaffolds could be used as a local controlled release system for vancomycin. We also investigated the efficiency of the scaffolds in eliminating infections and repairing osteomyelitis defects in rabbits. The gelatin scaffolds containing differing amounts of of β-TCP (0%, 10%, 30% and 50%) were prepared for controlled release of vancomycin and were labelled G-TCP0, G-TCP1, G-TCP3 and G-TCP5, respectively. The Kirby-Bauer method was used to examine the release profile. Chronic osteomyelitis models of rabbits were established. After thorough debridement, the osteomyelitis defects were implanted with the scaffolds. Radiographs and histological examinations were carried out to investigate the efficiency of eliminating infections and repairing bone defects.Objective
Methods
The purpose of this study was to compare the clinical and radiographic
outcomes of total ankle arthroplasty (TAA) in patients with pre-operatively
moderate and severe arthritic varus ankles to those achieved for
patients with neutral ankles. A total of 105 patients (105 ankles), matched for age, gender,
body mass index, and follow-up duration, were divided into three
groups by pre-operative coronal plane tibiotalar angle; neutral
(<
5°), moderate (5° to 15°) and severe (>
15°) varus deformity.
American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot
score, a visual analogue scale (VAS), and Short Form (SF)-36 score
were used to compare the clinical outcomes after a mean follow-up period
of 51 months (24 to 147).Aims
Patients and Methods
Temperature is known to influence muscle physiology, with the velocity of shortening, relaxation and propagation all increasing with temperature. Scant data are available, however, regarding thermal influences on energy required to induce muscle damage. Gastrocnemius and soleus muscles were harvested from 36 male rat limbs and exposed to increasing impact energy in a mechanical test rig. Muscle temperature was varied in 5°C increments, from 17°C to 42°C (to encompass the Objectives
Methods
Initial stability of tibial trays is crucial for long-term success of total knee arthroplasty (TKA) in both primary and revision settings. Rotating platform (RP) designs reduce torque transfer at the tibiofemoral interface. We asked if this reduced torque transfer in RP designs resulted in subsequently reduced micromotion at the cemented fixation interface between the prosthesis component and the adjacent bone. Composite tibias were implanted with fixed and RP primary and revision tibial trays and biomechanically tested under up to 2.5 kN of axial compression and 10° of external femoral component rotation. Relative micromotion between the implanted tibial tray and the neighbouring bone was quantified using high-precision digital image correlation techniques.Objectives
Methods
Infection following total hip or knee arthroplasty is a serious
complication. We noted an increase in post-operative infection in
cases carried out in temporary operating theatres. We therefore
compared those cases performed in standard and temporary operating
theatres and examined the deep periprosthetic infection rates. A total of 1223 primary hip and knee arthroplasties were performed
between August 2012 and June 2013. A total of 539 (44%) were performed
in temporary theatres. The two groups were matched for age, gender,
body mass index and American Society of Anesthesiologists grade.Aims
Patients and methods
The interaction between surgical lighting and laminar airflow
is poorly understood. We undertook an experiment to identify any
effect contemporary surgical lights have on laminar flow and recommend
practical strategies to limit any negative effects. Neutrally buoyant bubbles were introduced into the surgical field
of a simulated setup for a routine total knee arthroplasty in a
laminar flow theatre. Patterns of airflow were observed and the
number of bubbles remaining above the surgical field over time identified.
Five different lighting configurations were assessed. Data were analysed
using simple linear regression after logarithmic transformation.Aims
Materials and Methods
