Aims
Patients and Methods
Loosening is a well-known complication in the fixation of fractures using devices such as locking plates or unilateral fixators. It is believed that high strains in the bone at the bone-screw interface can initiate loosening, which can result in infection, and further loosening. Here, we present a new theory of loosening of implants. The time-dependent response of bone subjected to loads results in interfacial deformations in the bone which accumulate with cyclical loading and thus accentuates loosening. We used an ‘ideal’ bone-screw system, in which the screw is subjected to cyclical lateral loads and trabecular bone is modelled as non-linear viscoelastic and non-linear viscoelastic-viscoplastic material, based on recent experiments, which we conducted.Aims
Methods
This study investigates the reporting of health-related quality of life (HRQoL) in patients following hip fracture. We compare the relative merits and make recommendations for the use for two methods of measuring HRQoL; (i) including patients who died during follow-up and (ii) including survivors only. The World Hip Trauma Evaluation has previously reported changes in HRQoL using EuroQol-5D for patients with hip fractures. We performed additional analysis to investigate the effect of including or excluding those patients who died during the first four months of the follow-up period.Objectives
Methods
The aim of this study was to compare the cost-effectiveness of
intramedullary nail fixation and ‘locking’ plate fixation in the
treatment of extra-articular fractures of the distal tibia. An economic evaluation was conducted from the perspective of
the United Kingdom National Health Service (NHS) and personal social
services (PSS), based on evidence from the Fixation of Distal Tibia
Fractures (UK FixDT) multicentre parallel trial. Data from 321 patients
were available for analysis. Costs were collected prospectively
over the 12-month follow-up period using trial case report forms
and participant-completed questionnaires. Cost-effectiveness was
reported in terms of incremental cost per quality adjusted life
year (QALY) gained, and net monetary benefit. Sensitivity analyses
were conducted to test the robustness of cost-effectiveness estimates.Aim
Patients and Methods
Aims
Patients and Methods
The aim of this study was to compare the cost-effectiveness of
treatment with an osseointegrated percutaneous (OI-) prosthesis
and a socket-suspended (S-) prosthesis for patients with a transfemoral
amputation. A Markov model was developed to estimate the medical costs and
changes in quality-adjusted life-years (QALYs) attributable to treatment
of unilateral transfemoral amputation over a projected period of
20 years from a healthcare perspective. Data were collected alongside
a prospective clinical study of 51 patients followed for two years.Aims
Patients and Methods
The aim of this study was to estimate economic outcomes associated with deep surgical site infection (SSI) in patients with an open fracture of the lower limb. A total of 460 patients were recruited from 24 specialist trauma hospitals in the United Kingdom Major Trauma Network. Preference-based health-related quality-of-life outcomes, assessed using the EuroQol EQ-5D-3L and the 6-Item Short-Form Health Survey questionnaire (SF-6D), and economic costs (£, 2014/2015 prices) were measured using participant-completed questionnaires over the 12 months following injury. Descriptive statistics and multivariate regression analysis were used to explore the relationship between deep SSI and health utility scores, quality-adjusted life-years (QALYs), and health and personal social service (PSS) costs.Aims
Patients and Methods
Opening wedge high tibial osteotomy (HTO) is an established surgical procedure for the treatment of early-stage knee arthritis. Other than infection, the majority of complications are related to mechanical factors – in particular, stimulation of healing at the osteotomy site. This study used finite element (FE) analysis to investigate the effect of plate design and bridging span on interfragmentary movement (IFM) and the influence of fracture healing on plate stress and potential failure. A 10° opening wedge HTO was created in a composite tibia. Imaging and strain gauge data were used to create and validate FE models. Models of an intact tibia and a tibia implanted with a custom HTO plate using two different bridging spans were validated against experimental data. Physiological muscle forces and different stages of osteotomy gap healing simulating up to six weeks postoperatively were then incorporated. Predictions of plate stress and IFM for the custom plate were compared against predictions for an industry standard plate (TomoFix).Objectives
Materials and Methods
Enhanced micromotions between the implant and surrounding bone can impair osseointegration, resulting in fibrous encapsulation and aseptic loosening of the implant. Since the effect of micromotions on human bone cells is sparsely investigated, an Micromotions ranging from 25 µm to 100 µm were applied as sine or triangle signal with 1 Hz frequency to human osteoblasts seeded on collagen scaffolds. Micromotions were applied for six hours per day over three days. During the micromotions, a static pressure of 527 Pa was exerted on the cells by Ti6Al4V cylinders. Osteoblasts loaded with Ti6Al4V cylinders and unloaded osteoblasts without micromotions served as controls. Subsequently, cell viability, expression of the osteogenic markers collagen type I, alkaline phosphatase, and osteocalcin, as well as gene expression of osteoprotegerin, receptor activator of NF-κB ligand, matrix metalloproteinase-1, and tissue inhibitor of metalloproteinase-1, were investigated.Objectives
Methods
The Fluid Lavage in Open Fracture Wounds (FLOW) trial was a multicentre,
blinded, randomized controlled trial that used a 2 × 3 factorial
design to evaluate the effect of irrigation solution (soap Participants completed the Short Form-12 (SF-12) and the EuroQol-5
Dimensions (EQ-5D) at baseline (pre-injury recall), at two and six
weeks, and at three, six, nine and 12-months post-fracture. We calculated
the Physical Component Score (PCS) and the Mental Component Score
(MCS) of the SF-12 and the EQ-5D utility score, conducted an analysis
using a multi-level generalized linear model, and compared differences
between the baseline and 12-month scores.Aims
Patients and Methods
The aim of this independent multicentre study was to assess the
mid-term results of mobile bearing unicondylar knee arthroplasty
(UKA) for isolated lateral osteoarthritis of the knee joint. We retrospectively evaluated 363 consecutive, lateral UKAs (346
patients) performed using the Oxford domed lateral prosthesis undertaken
in three high-volume knee arthroplasty centres between 2006 and
2014. Mean age of the patients at surgery was 65 years (36 to 88)
with a mean final follow-up of 37 months (12 to 93)Aims
Patients and Methods
The Walch Type C dysplastic glenoid is characterized by excessive
retroversion. This anatomical study describes its morphology. A total of 29 shoulders with a dysplastic glenoid were analyzed.
CT was used to measure retroversion, inclination, height, width,
radius-of-curvature, surface area, depth, subluxation of the humeral
head and the Goutallier classification of fatty infiltration. The
severity of dysplasia and deficiency of the posterior rim of the
glenoid were recorded.Aims
Patients and Methods
The aim of this study was to determine the stability of a new
short femoral stem compared with a conventional femoral stem in
patients undergoing cementless total hip arthroplasty (THA), in
a prospective randomized controlled trial using radiostereometric
analysis (RSA). A total of 53 patients were randomized to receive cementless
THA with either a short femoral stem (MiniHip, 26 patients, mean
age: 52 years, nine male) or a conventional length femoral stem
(MetaFix, 23 patients, mean age: 53 years, 11 male). All patients
received the same cementless acetabular component. Two-year follow-up
was available on 38 patients. Stability was assessed through migration
and dynamically inducible micromotion. Radiographs for RSA were
taken postoperatively and at three, six, 12, 18, and 24 months.Aims
Patients and Methods
To assess the accuracy of patient-specific instruments (PSIs) CT scans were obtained from five female cadaveric pelvises. Five osteotomies were designed using Mimics software: sacroiliac, biplanar supra-acetabular, two parallel iliopubic and ischial. For cases of the left hemipelvis, PSIs were designed to guide standard oscillating saw osteotomies and later manufactured using 3D printing. Osteotomies were performed using the standard manual technique in cases of the right hemipelvis. Post-resection CT scans were quantitatively analysed. Student’s Objectives
Methods
Pedicle-lengthening osteotomy is a novel surgery for lumbar spinal stenosis (LSS), which achieves substantial enlargement of the spinal canal by expansion of the bilateral pedicle osteotomy sites. Few studies have evaluated the impact of this new surgery on spinal canal volume (SCV) and neural foramen dimension (NFD) in three different types of LSS patients. CT scans were performed on 36 LSS patients (12 central canal stenosis (CCS), 12 lateral recess stenosis (LRS), and 12 foraminal stenosis (FS)) at L4-L5, and on 12 normal (control) subjects. Mimics 14.01 workstation was used to reconstruct 3D models of the L4-L5 vertebrae and discs. SCV and NFD were measured after 1 mm, 2 mm, 3 mm, 4 mm, or 5 mm pedicle-lengthening osteotomies at L4 and/or L5. One-way analysis of variance was used to examine between-group differences.Objectives
Methods
The Precice nail is the latest intramedullary lengthening nail with excellent early outcomes. Implant complications have led to modification of the nail design. The aim of this study was to perform a retrieval study of Precice nails following lower-limb lengthening and to assess macroscopical and microscopical changes to the implants and evaluate differences following design modification, with the aim of identifying potential surgical, implant, and patient risk factors. A total of 15 nails were retrieved from 13 patients following lower-limb lengthening. Macroscopical and microscopical surface damage to the nails were identified. Further analysis included radiology and micro-CT prior to sectioning. The internal mechanism was then analyzed with scanning electron microscopy and energy dispersive x-ray spectroscopy to identify corrosion.Objectives
Methods
What represents clinically significant acetabular undercoverage
in patients with symptomatic cam-type femoroacetabular impingement
(FAI) remains controversial. The aim of this study was to examine
the influence of the degree of acetabular coverage on the functional
outcome of patients treated arthroscopically for cam-type FAI. Between October 2005 and June 2016, 88 patients (97 hips) underwent
arthroscopic cam resection and concomitant labral debridement and/or
refixation. There were 57 male and 31 female patients with a mean
age of 31.0 years (17.0 to 48.5) and a mean body mass index (BMI)
of 25.4 kg/m2 (18.9 to 34.9). We used the Hip2Norm, an
object-oriented-platform program, to perform 3D analysis of hip
joint morphology using 2D anteroposterior pelvic radiographs. The lateral
centre-edge angle, anterior coverage, posterior coverage, total
femoral coverage, and alpha angle were measured for each hip. The
presence or absence of crossover sign, posterior wall sign, and
the value of acetabular retroversion index were identified automatically
by Hip2Norm. Patient-reported outcome scores were collected preoperatively
and at final follow-up with the Hip Disability and Osteoarthritis
Outcome Score (HOOS).Aims
Patients and Methods
The aim of this study was to record the incidence of post-traumatic
osteoarthritis (OA), the need for total hip arthroplasty (THA),
and patient-reported outcome measures (PROMS) after surgery for
a fracture of the acetabulum, in our centre. All patients who underwent surgery for an acetabular fracture
between 2004 and 2014 were included. Patients completed the 36-Item
Short Form Health Survey (SF-36) and the modified Harris Hip Score
(mHHS) questionnaires. A retrospective chart and radiographic review
was performed on all patients. CT scans were used to assess the classification
of the fracture and the quality of reduction.Aims
Patients and Methods