Advances in polyethylene (PE) in total hip arthroplasty
have led to interest and increased use of highly crosslinked PE
(HXLPE) in total knee arthroplasty (TKA). Biomechanical data suggest
improved wear characteristics for HXLPE inserts over conventional
PE in TKA. Short-term results from registry data and few clinical
trials are promising. Our aim is to present a review of the history
of HXLPEs, the use of HXLPE inserts in TKA, concerns regarding potential mechanical
complications, and a thorough review of the available biomechanical
and clinical data. Cite this article:
In the initial development of total shoulder arthroplasty (TSA),
the humeral component was usually fixed with cement. Cementless
components were subsequently introduced. The aim of this study was
to compare the long-term outcome of cemented and cementless humeral
components in arthroplasty of the shoulder. All patients who underwent primary arthroplasty of the shoulder
at our institution between 1970 and 2012 were included in the study.
There were 4636 patients with 1167 cemented humeral components and
3469 cementless components. Patients with the two types of fixation
were matched for nine different covariates using a propensity score
analysis. A total of 551 well-balanced pairs of patients with cemented
and cementless components were available after matching for comparison
of the outcomes. The clinical outcomes which were analysed included loosening
of the humeral component determined at revision surgery, periprosthetic
fractures, post-operative infection and operating time.Aims
Patients and Methods
To investigate the outcomes of treatment of streptococcal periprosthetic
joint infection (PJI) involving total knee and hip arthroplasties. Streptococcal PJI episodes which occurred between January 2009
and December 2015 were identified from clinical databases. Presentation
and clinical outcomes for 30 streptococcal PJIs in 30 patients (12
hip and 18 knee arthroplasties) following treatment were evaluated
from the medical notes and at review. The Kaplan-Meier survival method
was used to estimate the probability of infection-free survival.
The influence of the biofilm active antibiotic rifampin was also
assessed.Aims
Patients and Methods
To examine the rates of hamstring graft salvage with arthroscopic
debridement of infected anterior cruciate ligament (ACL) reconstruction
as reported in the literature and discuss functional outcomes. A search was performed without language restriction on PubMed,
EMBASE, Ovid, CINAHL and Cochrane Register of Controlled Trials
(CENTRAL) databases from their inception to April 2015. We identified
147 infected hamstring grafts across 16 included studies. Meta-analysis
was performed using a random-effects model to estimate the overall
graft salvage rate, incorporating two different definitions of graft
salvage.Aims
Materials and Methods
We present a case series of ten metal-on-polyethylene total hip
arthroplasties (MoP THAs) with delayed dislocation associated with
unrecognised adverse local tissue reaction due to corrosion at the
trunnion and pseudotumour formation. The diagnosis was not suspected in nine of the ten patients (six
female/four male; mean age 66 years), despite treatment in a specialist
unit (mean time from index surgery to revision was 58 months, 36
to 84). It was identified at revision surgery and subsequently confirmed
by histological examination of resected tissue. Pre-operative assessment
and culture results ruled out infection. A variety of treatment
strategies were used, including resection of the pseudotumour and
efforts to avoid recurrent dislocation. Aims
Methods
This review summarises the technique of impaction
grafting with mesh augmentation for the treatment of uncontained
acetabular defects in revision hip arthroplasty. The ideal acetabular revision should restore bone stock, use
a small socket in the near-anatomic position, and provide durable
fixation. Impaction bone grafting, which has been in use for over
40 years, offers the ability to achieve these goals in uncontained
defects. The precepts of modern, revision impaction grafting are
that the segmental or cavitary defects must be supported with a
mesh; the contained cavity is filled with vigorously impacted morselised
fresh-frozen allograft; and finally, acrylic cement is used to stabilise
the graft and provide rigid, long-lasting fixation of the revised
acetabular component. Favourable results have been published with this technique. While
having its limitations, it is a viable option to address large acetabular
defects in revision arthroplasty. Cite this article:
The December 2014 Hip &
Pelvis Roundup360 looks at: Sports and total hips; topical tranexamic acid and blood conservation in hip replacement; blind spots and biases in hip research; no recurrence in cam lesions at two years; to drain or not to drain?; sonication and diagnosis of implant associated infection; and biomarkers and periprosthetic infection
The last decade has seen a considerable increase
in the use of in total ankle arthroplasty (TAA) to treat patients
with end-stage arthritis of the ankle. However, the longevity of
the implants is still far from that of total knee and hip arthroplasties. The aim of this review is to outline a diagnostic and treatment
algorithm for the painful TAA to be used when considering revision
surgery. Cite this article:
The April 2014 Hip & Pelvis Roundup360 looks at: Recent arthroplasty and flight; whether that squeak could be a fracture; diagnosing early infected hip replacement; impaction grafting at a decade; whether squeaking is more common than previously thought; femoral offset associated with post THR outcomes; and periprosthetic fracture stabilisation.
The high revision rates of the DePuy Articular Surface Replacement (ASR) and the DePuy ASR XL (the total hip arthroplasty (THA) version) have led to questions over the viability of metal-on-metal (MoM) hip joints. Some designs of MoM hip joint do, however, have reasonable mid-term performance when implanted in appropriate patients. Investigations into the reasons for implant failure are important to offer help with the choice of implants and direction for future implant designs. One way to assess the performance of explanted hip prostheses is to measure the wear (in terms of material loss) on the joint surfaces. In this study, a coordinate measuring machine (CMM) was used to measure the wear on five failed cementless Biomet Magnum/ReCap/ Taperloc large head MoM THAs, along with one Biomet ReCap resurfacing joint. Surface roughness measurements were also taken. The reason for revision of these implants was pain and/or adverse reaction to metal debris (ARMD) and/or elevated blood metal ion levels.Objectives
Methods
Despite many claims of good wear properties following
total knee replacement (TKR) with an oxidised zirconium (OxZr) femoral
component, there are conflicting clinical results. We hypothesised
that there would be no difference in either the mid-term clinical
and radiological outcomes or the characteristics of the polyethylene
wear particles (weight, size and shape) in patients using an OxZr
or cobalt-chrome (CoCr) femoral component. In all 331 patients underwent
bilateral TKR, receiving an OxZr femoral component in one knee and
a CoCr femoral component in the other. The mean follow-up was 7.5
years (6 to 8). Following aspiration, polyethylene wear particles
were analysed using thermogravimetric methods and scanning electron
microscopy. At the most recent follow-up, the mean Knee Society
score, Western Ontario and McMaster Universities Osteoarthritis
Index score, range of movement and satisfaction score were not significantly
different in the two groups. The mean weight, size, aspect ratio
and roundness of the aspirated wear particles were similar for each
femoral component. Survivorship of the femoral, tibial and patellar
components was 100% in both groups. In the absence of evidence of an advantage in the medium term
we cannot justify the additional expense of an OxZr femoral component.
Periprosthetic joint infection (PJI) is one of
the most feared and challenging complications following total knee arthroplasty.
We provide a detailed description of our current understanding regarding
the management of PJI of the knee, including diagnostic aids,
pre-operative planning, surgical treatment, and outcome. Cite this article:
The aim of our study was to describe the characteristics,
treatment, and outcomes of patients with periprosthetic joint infection
(PJI) and normal inflammatory markers after total knee arthroplasty
(TKA) and total hip arthroplasty (THA). In total 538 TKAs and 414 THAs underwent surgical treatment for
PJI and met the inclusion criteria. Pre-operative erythrocyte sedimentation
rate (ESR) and C-reactive protein level (CRP) were reviewed to identify
the seronegative cohort. An age- and gender-matched cohort was identified
from the remaining patients for comparison. Overall, 4% of confirmed
infections were seronegative (21 TKA and 17 THA). Of those who underwent
pre-operative aspiration, cultures were positive in 76% of TKAs
(n = 13) and 64% of THAs (n = 7). Cell count and differential were
suggestive of infection in 85% of TKA (n = 11) and all THA aspirates
(n = 5). The most common organism was coagulase-negative Cite this article:
Osteoarthritis (OA) is an important cause of
pain, disability and economic loss in humans, and is similarly important in
the horse. Recent knowledge on post-traumatic OA has suggested opportunities
for early intervention, but it is difficult to identify the appropriate
time of these interventions. The horse provides two useful mechanisms
to answer these questions: 1) extensive experience with clinical
OA in horses; and 2) use of a consistently predictable model of
OA that can help study early pathobiological events, define targets
for therapeutic intervention and then test these putative therapies.
This paper summarises the syndromes of clinical OA in horses including
pathogenesis, diagnosis and treatment, and details controlled studies
of various treatment options using an equine model of clinical OA.
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 April 2013 Research Roundup360 looks at: when the ‘residency cake’ is done; steroids, stem cells and tendons; what exactly is osteoarthritis; platelet-rich plasma; CRPS; d-Dimer for DVT; reducing bacterial adhesion; and fin or limb?