Periprosthetic fracture is a significant complication of total
hip and knee arthroplasty. This study aimed to describe the survival
of patients sustaining periprosthetic femoral fractures and compare
this with that of the general population, as well as to identify
the factors that influence survival. A total of 151 patients (women: men 116:35, mean age 74.6 years,
standard deviation 11.5) that sustained a periprosthetic fracture
between January 2005 and October 2012 were retrospectively analysed.
Epidemiological data, comorbidities, type of surgical management,
type of implant, and mortality data were studied.Aims
Patients and Methods
There is increasing global awareness of adverse
reactions to metal debris and elevated serum metal ion concentrations
following the use of second generation metal-on-metal total hip
arthroplasties. The high incidence of these complications can be
largely attributed to corrosion at the head-neck interface. Severe
corrosion of the taper is identified most commonly in association
with larger diameter femoral heads. However, there is emerging evidence
of varying levels of corrosion observed in retrieved components
with smaller diameter femoral heads. This same mechanism of galvanic
and mechanically-assisted crevice corrosion has been observed in
metal-on-polyethylene and ceramic components, suggesting an inherent
biomechanical problem with current designs of the head-neck interface. We provide a review of the fundamental questions and answers
clinicians and researchers must understand regarding corrosion of
the taper, and its relevance to current orthopaedic practice. Cite this article:
The purpose of the present study was to examine the long-term
fixation of a cemented fixed-bearing polished titanium tibial baseplate
(Genesis ll). Patients enrolled in a previous two-year prospective trial (n
= 35) were recalled at ten years. Available patients (n = 15) underwent
radiostereometric analysis (RSA) imaging in a supine position using
a conventional RSA protocol. Migration of the tibial component in
all planes was compared between initial and ten-year follow-up.
Outcome scores including the Knee Society Score, Western Ontario
and McMaster Universities Arthritis Index, 12-item Short Form Health
Survey, Forgotten Joint Score, and University of California, Los
Angeles Activity Score were recorded.Aims
Patients and Methods
Recently, the use of metal-on-metal articulations
in total hip arthroplasty (THA) has led to an increase in adverse
events owing to local soft-tissue reactions from metal ions and
wear debris. While the majority of these implants perform well,
it has been increasingly recognised that a small proportion of patients
may develop complications secondary to systemic cobalt toxicity
when these implants fail. However, distinguishing true toxicity
from benign elevations in cobalt ion levels can be challenging. The purpose of this two part series is to review the use of cobalt
alloys in THA and to highlight the following related topics of interest:
mechanisms of cobalt ion release and their measurement, definitions
of pathological cobalt ion levels, and the pathophysiology, risk factors
and treatment of cobalt toxicity. Historically, these metal-on-metal
arthroplasties are composed of a chromium-cobalt articulation. The release of cobalt is due to the mechanical and oxidative
stresses placed on the prosthetic joint. It exerts its pathological
effects through direct cellular toxicity. This manuscript will highlight the pathophysiology of cobalt
toxicity in patients with metal-on-metal hip arthroplasties. Take home message: Patients with new or evolving hip symptoms
with a prior history of THA warrant orthopaedic surgical evaluation.
Increased awareness of the range of systemic symptoms associated
with cobalt toxicity, coupled with prompt orthopaedic intervention, may
forestall the development of further complications. Cite this article:
Up to 40% of unicompartmental knee arthroplasty (UKA) revisions are performed for unexplained pain which may be caused by elevated proximal tibial bone strain. This study investigates the effect of tibial component metal backing and polyethylene thickness on bone strain in a cemented fixed-bearing medial UKA using a finite element model (FEM) validated experimentally by digital image correlation (DIC) and acoustic emission (AE). A total of ten composite tibias implanted with all-polyethylene (AP) and metal-backed (MB) tibial components were loaded to 2500 N. Cortical strain was measured using DIC and cancellous microdamage using AE. FEMs were created and validated and polyethylene thickness varied from 6 mm to 10 mm. The volume of cancellous bone exposed to < -3000 µε (pathological loading) and < -7000 µε (yield point) minimum principal (compressive) microstrain and > 3000 µε and > 7000 µε maximum principal (tensile) microstrain was computed.Objectives
Materials and Methods
Fractures of the distal femur can be challenging to manage and
are on the increase in the elderly osteoporotic population. Management
with casting or bracing can unacceptably limit a patient’s ability
to bear weight, but historically, operative fixation has been associated
with a high rate of re-operation. In this study, we describe the outcomes
of fixation using modern implants within a strategy of early return
to function. All patients treated at our centre with lateral distal femoral
locking plates (LDFLP) between 2009 and 2014 were identified. Fracture
classification and operative information including weight-bearing
status, rates of union, re-operation, failure of implants and mortality
rate, were recorded.Aims
Patients and Methods
High failure rates of metal-on-metal hip arthroplasty implants have highlighted the need for more careful introduction and monitoring of new implants and for the evaluation of the safety of medical devices. The National Joint Registry and other regulatory services are unable to detect failing implants at an early enough stage. We aimed to identify validated surrogate markers of long-term outcome in patients undergoing primary total hip arthroplasty (THA). We conducted a systematic review of studies evaluating surrogate markers for predicting long-term outcome in primary THA. Long-term outcome was defined as revision rate of an implant at ten years according to National Institute of Health and Care Excellence guidelines. We conducted a search of Medline and Embase (OVID) databases. Separate search strategies were devised for the Cochrane database and Google Scholar. Each search was performed to include articles from the date of their inception to June 8, 2015.Objectives
Methods
The leading indication for revision total hip
arthroplasty (THA) remains aseptic loosening owing to wear. The younger,
more active patients currently undergoing THA present unprecedented
demands on the bearings. Ceramic-on-ceramic (CoC) bearings have
consistently shown the lowest rates of wear. The recent advances,
especially involving alumina/zirconia composite ceramic, have led
to substantial improvements and good results Alumina/zirconia composite ceramics are extremely hard, scratch
resistant and biocompatible. They offer a low co-efficient of friction
and superior lubrication and lower rates of wear compared with other
bearings. The major disadvantage is the risk of fracture of the
ceramic. The new composite ceramic has reduced the risk of fracture
of the femoral head to 0.002%. The risk of fracture of the liner
is slightly higher (0.02%). Assuming that the components are introduced without impingement,
CoC bearings have major advantages over other bearings. Owing to
the superior hardness, they produce less third body wear and are
less vulnerable to intra-operative damage. The improved tribology means that CoC bearings are an excellent
choice for young, active patients requiring THA. Cite this article:
We assessed the long-term (more than ten-year) outcomes of the
Kudo type-5 elbow prosthesis in patients with rheumatoid arthritis
(RA). We reviewed 41 elbows (Larsen Grade IV, n = 21; Grade V, n =
20) in 31 patients with RA who had undergone a Kudo type-5 total
elbow arthroplasty (TEA) between 1994 and 2003, and had been followed
up for more than ten years. The humeral component was cementless
and the all-polyethylene ulnar component cemented in every patient. Clinical
outcome was assessed using the Mayo elbow performance score. We
calculated the revision rate and evaluated potential risk factors
for revision. The duration of follow-up was a mean 141 months (120
to 203).Aims
Materials and Methods
Tibiofemoral alignment is important to determine the rate of
progression of osteoarthritis and implant survival after total knee
arthroplasty (TKA). Normally, surgeons aim for neutral tibiofemoral
alignment following TKA, but this has been questioned in recent
years. The aim of this study was to evaluate whether varus or valgus
alignment indeed leads to increased medial or lateral tibiofemoral
forces during static and dynamic weight-bearing activities. Tibiofemoral contact forces and moments were measured in nine
patients with instrumented knee implants. Medial force ratios were
analysed during nine daily activities, including activities with
single-limb support (e.g. walking) and double-limb support (e.g.
knee bend). Hip-knee-ankle angles in the frontal plane were analysed
using full-leg coronal radiographs. Aims
Patients and Methods
The aim of this study was to establish what happens to patients
in the long term after endoprosthetic replacement for a primary
malignant tumour of bone. We conducted a retrospective analysis of a prospectively maintained
database to identify all patients who had undergone an endoprosthetic
replacement more than 25 years ago and who were still alive. Their
outcomes were investigated with reference to their complications and
need for further surgery. A total of 230 patients were identified.
Their mean age at diagnosis was 20.7 years (five to 62). The most
common diagnosis was osteosarcoma (132). The most common site was
the distal femur (102). Aims
Patients and Methods
T-cells are considered to play an important role in the inflammatory response causing arthroplasty failure. The study objectives were to investigate the composition and distribution of CD4+ T-cell phenotypes in the peripheral blood (PB) and synovial fluid (SF) of patients undergoing revision surgery for failed metal-on-metal (MoM) and metal-on-polyethylene (MoP) hip arthroplasties, and in patients awaiting total hip arthroplasty. In this prospective case-control study, PB and SF were obtained from 22 patients (23 hips) undergoing revision of MoM (n = 14) and MoP (n = 9) hip arthroplasties, with eight controls provided from primary hip osteoarthritis cases awaiting arthroplasty. Lymphocyte subtypes in samples were analysed using flow cytometry.Objectives
Methods
Ultraviolet (UV) light-mediated photofunctionalisation is known to improve osseointegration of pure titanium (Ti). However, histological examination of titanium alloy (Ti6Al4V), which is frequently applied in orthopaedic and dental surgery, has not yet been performed. This study examined the osseointegration of photofunctionalised Ti6Al4V implants. Ti and Ti6Al4V implants were treated with UV light, and the chemical composition and contact angle on the surfaces were evaluated to confirm photofunctionalisation. The implants were inserted into femurs in rats, and the rats were killed two or four weeks after the surgery. For histomorphometric analysis, both the bone–implant contact (BIC) ratio and the bone volume (BV) ratio were calculated from histological analysis and microcomputed tomography data.Objectives
Methods
Pelvic reconstruction after the resection of a tumour around
the acetabulum is a challenging procedure due to the complex anatomy
and biomechanics. Several pelvic endoprostheses have been introduced,
but the rates of complication remain high. Our aim was to review
the use of a stemmed acetabular pedestal cup in the management of
these patients. The study involved 48 patients who underwent periacetabular reconstruction
using a stemmed pedestal cup (Schoellner cup; Zimmer Biomet Inc.,
Warsaw, Indiana) between 2000 and 2013. The indications for treatment included
a primary bone tumour in 27 patients and metastatic disease in 21
patients. The mean age of the patients at the time of surgery was
52 years (16 to 83).Aims
Patients and Methods
The purpose of this study was to compare the results and complications of tibial lengthening over an intramedullary nail with treatment using the traditional Ilizarov method. In this matched case study, 16 adult patients underwent 19 tibial lengthening over nails (LON) procedures. For the matched case group, 17 patients who underwent 19 Ilizarov tibial lengthenings were retrospectively matched to the LON group.Objectives
Methods
Lumbar fusion is known to reduce the variation in pelvic tilt
between standing and sitting. A flexible lumbo-pelvic unit increases
the stability of total hip arthroplasty (THA) when seated by increasing
anterior clearance and acetabular anteversion, thereby preventing
impingement of the prosthesis. Lumbar fusion may eliminate this protective
pelvic movement. The effect of lumbar fusion on the stability of
total hip arthroplasty has not previously been investigated. The Medicare database was searched for patients who had undergone
THA and spinal fusion between 2005 and 2012. PearlDiver software
was used to query the database by the International Classification
of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) procedural
code for primary THA and lumbar spinal fusion. Patients who had
undergone both lumbar fusion and THA were then divided into three
groups: 1 to 2 levels, 3 to 7 levels and 8+ levels of fusion. The
rate of dislocation in each group was established using ICD-9-CM codes.
Patients who underwent THA without spinal fusion were used as a
control group. Statistical significant difference between groups
was tested using the chi-squared test, and significance set at p
<
0.05.Aims
Patients and Methods
