Ceramic-on-ceramic (CoC) bearings in total hip arthroplasty (THA)
are commonly used, but concerns exist regarding ceramic fracture.
This study aims to report the risk of revision for fracture of modern
CoC bearings and identify factors that might influence this risk,
using data from the National Joint Registry (NJR) for England, Wales, Northern
Ireland and the Isle of Man. We analysed data on 223 362 bearings from 111 681 primary CoC
THAs and 182 linked revisions for bearing fracture recorded in the
NJR. We used implant codes to identify ceramic bearing composition
and generated Kaplan-Meier estimates for implant survivorship. Logistic
regression analyses were performed for implant size and patient specific
variables to determine any associated risks for revision.Aims
Patients and Methods
The aim of this study was to investigate the effect of a posterior
malleolar fragment (PMF), with <
25% ankle joint surface, on
pressure distribution and joint-stability. There is still little
scientific evidence available to advise on the size of PMF, which
is essential to provide treatment. To date, studies show inconsistent
results and recommendations for surgical treatment date from 1940. A total of 12 cadaveric ankles were assigned to two study groups.
A trimalleolar fracture was created, followed by open reduction
and internal fixation. PMF was fixed in Group I, but not in Group
II. Intra-articular pressure was measured and cyclic loading was
performed.Aims
Materials and Methods
Posterior tilt of the pelvis with sitting provides biological
acetabular opening. Our goal was to study the post-operative interaction
of skeletal mobility and sagittal acetabular component position. This was a radiographic study of 160 hips (151 patients) who
prospectively had lateral spinopelvic hip radiographs for skeletal
and implant measurements. Intra-operative acetabular component position
was determined according to the pre-operative spinal mobility. Sagittal
implant measurements of ante-inclination and sacral acetabular angle were
used as surrogate measurements for the risk of impingement, and
intra-operative acetabular component angles were compared with these.Aims
Materials and Methods
The development and pre-clinical evaluation of
nano-texturised, biomimetic, surfaces of titanium (Ti) implants treated
with titanium dioxide (TiO2) nanotube arrays is reviewed. Cite this article:
The MAGnetic Expansion Control (MAGEC) system
is used increasingly in the management of early-onset scoliosis.
Good results have been published, but there have been recent reports
identifying implant failures that may be associated with significant
metallosis surrounding the implants. This article aims to present
the current knowledge regarding the performance of this implant,
and the potential implications and strategies that may be employed
to identify and limit any problems. We urge surgeons to apply caution to patient and construct selection;
engage in prospective patient registration using a spine registry;
ensure close clinical monitoring until growth has ceased; and send
all explanted MAGEC rods for independent analysis. The MAGEC system may be a good instrumentation system for the
treatment of early-onset scoliosis. However, it is innovative and
like all new technology, especially when deployed in a paediatric
population, robust systems to assess long-term outcome are required
to ensure that patient safety is maintained. Cite this article:
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
We present the ten-year data of a cohort of patients, aged between
18 and 65 years (mean age 52.7 years; 19 to 64), who underwent total
hip arthroplasty. Patients were randomised to be treated with a
cobalt-chrome (CoCr) femoral head with an ultra-high molecular weight
polyethylene (UHMWPE), highly cross-linked polyethylene (XLPE) or
ceramic-on-ceramic (CoC) bearing surface. A total of 102 hips (91 patients) were randomised into the three
groups. At ten years, 97 hips were available for radiological and
functional follow-up. Two hips (two patients) had been revised (one
with deep infection and one for periprosthetic fracture) and three
were lost to follow-up. Radiological analysis was performed using
a validated digital assessment programme to give linear, directional
and volumetric wear of the two polyethylene groups.Aims
Patients and Methods
The aim of this study was to determine whether the rates of revision
for metal-on-metal (MoM) total hip arthroplasties (THAs) with Pinnacle
components varied according to the year of the initial operation,
and compare these with the rates of revision for other designs of
MoM THA. Data from the National Joint Registry for England and Wales included
36 mm MoM THAs with Pinnacle acetabular components which were undertaken
between 2003 and 2012 with follow-up for at least five years (n
= 10 776) and a control group of other MoM THAs (n = 13 817). The
effect of the year of the primary operation on all-cause rates of revision
was assessed using Cox regression and interrupted time-series analysis.Aims
Patients and Methods
The increased The proximal penetration of the femoral head five years post-operatively
was measured for 15 patients using radiostereometric analysis (RSA).Aims
Patients and Methods
The success of anterior cruciate ligament reconstruction (ACLR)
depends on osseointegration at the graft-tunnel interface and intra-articular
ligamentization. Our aim was to conduct a systematic review of clinical
and preclinical studies that evaluated biological augmentation of
graft healing in ACLR. In all, 1879 studies were identified across three databases.
Following assessment against strict criteria, 112 studies were included
(20 clinical studies; 92 animal studies). Aims
Materials and Methods
This study sought to establish the prevalence of the cross over
sign (COS) and posterior wall sign (PWS) in relation to the anterior
pelvic plane (APP) in an asymptomatic population through reliable
and accurate 3D-CT based assessment. Data from pelvic CT scans of 100 asymptomatic subjects (200 hips)
undertaken for conditions unrelated to disorders of the hip were
available for analysis in this study. A previously established 3D
analysis method was applied to assess the prevalence of the COS
and PWS in relation to the APP.Aims
Materials and Methods
There are many guidelines that help direct the management of
patients with metal-on-metal (MOM) hip arthroplasties. We have undertaken
a study to compare the management of patients with MOM hip arthroplasties in
different countries. Six international tertiary referral orthopaedic centres were
invited to participate by organising a multi-disciplinary team (MDT)
meeting, consisting of two or more revision hip arthroplasty surgeons
and a musculoskeletal radiologist. A full clinical dataset including
history, blood tests and imaging for ten patients was sent to each
unit, for discussion and treatment planning. Differences in the
interpretation of findings, management decisions and rationale for
decisions were compared using quantitative and qualitative methods.Aims
Methods
Osteoporosis is a chronic disease. The aim of this study was to identify key genes in osteoporosis. Microarray data sets GSE56815 and GSE56814, comprising 67 osteoporosis blood samples and 62 control blood samples, were obtained from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) were identified in osteoporosis using Limma package (3.2.1) and Meta-MA packages. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed to identify biological functions. Furthermore, the transcriptional regulatory network was established between the top 20 DEGs and transcriptional factors using the UCSC ENCODE Genome Browser. Receiver operating characteristic (ROC) analysis was applied to investigate the diagnostic value of several DEGs.Objectives
Methods
Favourable results for collarless polished tapered stems have been reported, and cement creep due to taper slip may be a contributing factor. However, the ideal cement thickness around polished stems remains unknown. We investigated the influence of cement thickness on stem subsidence and cement creep. We cemented six collarless polished tapered (CPT) stems (two stems each of small, medium and large sizes) into composite femurs that had been reamed with a large CPT rasp to achieve various thicknesses of the cement mantle. Two or three tantalum balls were implanted in the proximal cement in each femur. A cyclic loading test was then performed for each stem. The migration of the balls was measured three-dimensionally, using a micro-computed tomography (CT) scanner, before and after loading. A digital displacement gauge was positioned at the stem shoulder, and stem subsidence was measured continuously by the gauge. Final stem subsidence was measured at the balls at the end of each stem.Objectives
Methods
Malalignment of the tibial component could influence the long-term survival of a total knee arthroplasty (TKA). The object of this study was to investigate the biomechanical effect of varus and valgus malalignment on the tibial component under stance-phase gait cycle loading conditions. Validated finite element models for varus and valgus malalignment by 3° and 5° were developed to evaluate the effect of malalignment on the tibial component in TKA. Maximum contact stress and contact area on a polyethylene insert, maximum contact stress on patellar button and the collateral ligament force were investigated.Objectives
Methods
All-suture anchors are increasingly used in rotator cuff repair procedures. Potential benefits include decreased bone damage. However, there is limited published evidence for the relative strength of fixation for all-suture anchors compared with traditional anchors. A total of four commercially available all-suture anchors, the ‘Y-Knot’ (ConMed), Q-FIX (Smith & Nephew), ICONIX (Stryker) and JuggerKnot (Zimmer Biomet) and a traditional anchor control TWINFIX Ultra PK Suture Anchor (Smith & Nephew) were tested in cadaveric human humeral head rotator cuff repair models (n = 24). This construct underwent cyclic loading applied by a mechanical testing rig (Zwick/Roell). Ultimate load to failure, gap formation at 50, 100, 150 and 200 cycles, and failure mechanism were recorded. Significance was set at p < 0.05.Objectives
Materials and Methods
Reconstruction of the acetabulum after failed total hip arthroplasty
(THA) can be a surgical challenge in the presence of severe bone
loss. We report the long-term survival of a porous tantalum revision
acetabular component, its radiological appearance and quality of
life outcomes. We reviewed the results of 46 patients who had undergone revision
of a failed acetabular component with a Paprosky II or III bone
defect and reconstruction with a hemispherical, tantalum acetabular
component, supplementary screws and a cemented polyethylene liner.Aims
Patients and Methods
