Aims. The risk of mechanical failure of modular revision hip stems is frequently mentioned in the literature, but little is currently known about the actual clinical failure rates of this type of prosthesis. The current retrospective long-term analysis examines the distal and modular failure patterns of the Prevision hip stem from 18 years of clinical use. A design improvement of the
Periprosthetic femoral fracture (PFF) is a potentially
devastating complication after total hip arthroplasty, with historically
high rates of complication and failure because of the technical
challenges of surgery, as well as the prevalence of advanced age
and comorbidity in the patients at risk. This study describes the short-term outcome after revision arthroplasty
using a
The aim of this study was to develop a novel computational model for estimating head/stem taper mechanics during different simulated assembly conditions. Finite element models of generic cobalt-chromium (CoCr) heads on a titanium stem taper were developed and driven using dynamic assembly loads collected from clinicians. To verify contact mechanics at the taper interface, comparisons of deformed microgroove characteristics (height and width of microgrooves) were made between model estimates with those measured from five retrieved implants. Additionally, these models were used to assess the role of assembly technique—one-hit versus three-hits—on the taper interlock mechanical behaviour.Aims
Methods
Tapered fluted titanium stems are increasingly
used for femoral revision arthroplasty. They are available in modular and
non-modular forms. Modularity has advantages when the bone loss
is severe, the proximal femur is mis shapen or the surgeon is unfamiliar
with the implant, but it introduces the risk of fracture of the
stem at the junction between it and the proximal body segment. For
that reason, and while awaiting intermediate-term results of more recently
introduced designs of this junction, non-modularity has attracted
attention, at least for straightforward revision cases. We review the risks and causes of fracture of tapered titanium
modular revision stems and present an argument in favour of the
more selective use of modular designs. Cite this article:
Aims. Revision total hip arthroplasty in patients with Vancouver type B3 fractures with Paprosky type IIIA, IIIB, and IV femoral defects are difficult to treat. One option for Paprovsky type IIIB and IV defects involves
Aims. Uncemented implants are now commonly used at reimplantation of a two-stage revision total hip arthoplasty (THA) following periprosthetic joint infection (PJI). However, there is a paucity of data on the performance of the most commonly used uncemented femoral implants –
We report our experience of revision total hip
replacement (THR) using the Revitan curved modular titanium fluted revision
stem in patients with a full spectrum of proximal femoral defects.
A total of 112 patients (116 revisions) with a mean age of 73.4
years (39 to 90) were included in the study. The mean follow-up
was 7.5 years (5.3 to 9.1). A total of 12 patients (12 hips) died
but their data were included in the survival analysis, and four
patients (4 hips) were lost to follow-up. The clinical outcome,
proximal bone regeneration and subsidence were assessed for 101
hips. The mean Harris Hip Score was 88.2 (45.8 to 100) after five years
and there was an increase of the mean Barnett and Nordin-Score,
a measure of the proximal bone regeneration, of 20.8 (-3.1 to 52.7).
Five stems had to be revised (4.3%), three (2.9%) showed subsidence,
five (4.3%) a dislocation and two of 85 aseptic revisions (2.3%)
a periprosthetic infection. At the latest follow-up, the survival with revision of the stem
as the endpoint was 95.7% (95% confidence interval 91.9% to 99.4%)
and with aseptic loosening as the endpoint, was 100%. Peri-prosthetic
fractures were not observed. We report excellent results with respect to subsidence, the risk
of fracture, and loosening after femoral revision using a modular
curved revision stem with distal cone-in-cone fixation. A successful
outcome depends on careful pre-operative planning and the use of
a transfemoral approach when the anatomy is distorted or a fracture
is imminent, or residual cement or a partially-secured existing
stem cannot be removed. The shortest appropriate stem should, in
our opinion, be used and secured with >
3 cm fixation at the femoral
isthmus, and distal interlocking screws should be used for additional
stability when this goal cannot be realised. Cite this article:
If a surgeon is faced with altered lesser trochanter
anatomy when revising the femoral component in revision total hip
replacement, a peri-prosthetic fracture, or Paprosky type IIIb or
type IV femoral bone loss, a
The early failure and revision of bimodular primary
total hip arthroplasty prostheses requires the identification of the
risk factors for material loss and wear at the taper junctions through
taper wear analysis. Deviations in taper geometries between revised
and pristine
We report a case of a male patient presenting
with bilateral painful but apparently well-positioned and -fixed
large-diameter metal-on-metal hip replacements four years post-operatively.
Multiple imaging modes revealed a thick-walled, cystic expansile
mass in communication with the hip joint (a pseudotumour). Implant
retrieval analysis and tissue culture eliminated high bearing wear
or infection as causes for the soft-tissue reaction, but noted marked corrosion
of the
We have evaluated the survivorship, outcomes, and failures of an interlocking, reconstruction-mode stem-sideplate implant used to preserve the native hip joint and achieve proximal fixation when there is little residual femur during large endoprosthetic reconstruction of the distal femur. A total of 14 patients underwent primary or revision reconstruction of a large femoral defect with a short remaining proximal femur using an interlocking, reconstruction-mode stem-sideplate for fixation after oncological distal femoral and diaphyseal resections. The implant was attached to a standard endoprosthetic reconstruction system. The implant was attached to a standard endoprosthetic reconstruction system. None of the femoral revisions were amenable to standard cemented or uncemented stem fixation. Patient and disease characteristics, surgical history, final ambulatory statusAims
Methods
The aim of this study was to evaluate the incidence of liner malseating in two commonly used dual-mobility (DM) designs. Secondary aims included determining the risk of dislocation, survival, and clinical outcomes. We retrospectively identified 256 primary total hip arthroplasties (THAs) that included a DM component (144 Stryker MDM and 112 Zimmer-Biomet G7) in 233 patients, performed between January 2012 and December 2019. Postoperative radiographs were reviewed independently for malseating of the liner by five reviewers. The mean age of the patients at the time of THA was 66 years (18 to 93), 166 (65%) were female, and the mean BMI was 30 kg/m2 (17 to 57). The mean follow-up was 3.5 years (2.0 to 9.2).Aims
Methods
Improvements in functional results and long-term survival are variable following conversion of hip fusion to total hip arthroplasty (THA) and complications are high. The aim of the study was to analyze the clinical and functional results in patients who underwent conversion of hip fusion to THA using a consistent technique and uncemented implants. A total of 39 hip fusion conversions to THA were undertaken in 38 patients by a single surgeon employing a consistent surgical technique and uncemented implants. Parameters assessed included Harris Hip Score (HHS) for function, range of motion (ROM), leg length discrepancy (LLD), satisfaction, and use of walking aid. Radiographs were reviewed for loosening, subsidence, and heterotopic ossification (HO). Postoperative complications and implant survival were assessed.Aims
Methods
Femoral revision component subsidence has been identified as predicting early failure in revision hip surgery. This comparative cohort study assessed the potential risk factors of subsidence in two commonly used femoral implant designs. A comparative cohort study was undertaken, analyzing a consecutive series of patients following revision total hip arthroplasties using either a tapered-modular (TM) fluted titanium or a porous-coated cylindrical modular (PCM) titanium femoral component, between April 2006 and May 2018. Clinical and radiological assessment was compared for both treatment cohorts. Risk factors for subsidence were assessed and compared.Aims
Methods
We evaluated a large database with mechanical failure of a single uncemented modular femoral component, used in revision hip arthroplasty, as the end point and compared them to a control group treated with the same implant. Patient- and implant-specific risk factors for implant failure were analyzed. All cases of a fractured uncemented modular revision femoral component from one manufacturer until April 2017 were identified and the total number of implants sold until April 2017 was used to calculate the fracture rate. The manufacturer provided data on patient demographics, time to failure, and implant details for all notified fractured devices. Patient- and implant-specific risk factors were evaluated using a logistic regression model with multiple imputations and compared to data from a previously published reference group, where no fractures had been observed. The results of a retrieval analysis of the fractured implants, performed by the manufacturer, were available for evaluation.Aims
Methods
Modular dual-mobility constructs reduce the risk of dislocation after revision total hip arthroplasty (THA). However, questions about metal ions from the cobalt-chromium (CoCr) liner persist, and are particularly germane to patients being revised for adverse local tissue reactions (ALTR) to metal. We determined the early- to mid-term serum Co and Cr levels after modular dual-mobility components were used in revision and complex primary THAs, and specifically included patients revised for ALTR. Serum Co and Cr levels were measured prospectively in 24 patients with a modular dual-mobility construct and a ceramic femoral head. Patients with CoCr heads or contralateral THAs with CoCr heads were excluded. The mean age was 63 years (35 to 83), with 13 patients (54%) being female. The mean follow-up was four years (2 to 7). Indications for modular dual-mobility were prosthetic joint infection treated with two-stage exchange and subsequent reimplantation (n = 8), ALTR revision (n = 7), complex primary THA (n = 7), recurrent instability (n = 1), and periprosthetic femoral fracture (n = 1). The mean preoperative Co and Cr in patients revised for an ALTR were 29.7 μg/l (2 to 146) and 21.5 μg/l (1 to 113), respectively.Aims
Patients and Methods
Radiostereometric analysis (RSA) studies of vitamin E-doped, highly crosslinked polyethylene (VEPE) liners show low head penetration rates in cementless acetabular components. There is, however, currently no data on cemented VEPE acetabular components in total hip arthroplasty (THA). The aim of this study was to evaluate the safety of a new cemented VEPE component, compared with a conventional polyethylene (PE) component regarding migration, head penetration, and clinical results. We enrolled 42 patients (21 male, 21 female) with osteoarthritis and a mean age of 67 years (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: