Aims. The aim of this study is to report the long-term outcomes of instrumented femoral revisions with impaction allograft bone grafting (IBG) using the X-change femoral revision system at 30 years after introduction of the technique. Methods. We updated the outcomes of our previous study, based on 208 consecutive revisions using IBG and the X-change femoral revision system in combination with a cemented
We retrospectively reviewed 175 patients (191 hips) who had undergone primary cemented total hip replacement between November 1992 and November 1995 using a collarless polished double-tapered femoral component after a minimum of ten years (mean 11.08; 10 to 12.8). All stems were implanted using contemporary cementing techniques with a distal cement restrictor, pressurised lavage, retrograde cementing with a gun and proximal pressurisation. Clinical outcome was assessed using the Harris Hip score. Radiological analysis was performed on calibrated plain radiographs taken in two planes. Complete radiological data on 110 patients (120 hips) and clinical follow-up on all the surviving 111 patients (122 hips) was available. The fate of all the hips was known. At final follow-up, the mean Harris Hip score was 86 (47 to 100), and 87 of 116 patients (75%) had good or excellent scores. Survival with revision of the stem for aseptic loosening as the endpoint was 100%; and survival with revision of the stem for any reason was 95.9% (95% confidence interval 87.8 to 96.8) at ten years. All the stems subsided vertically at the stem-cement interface in a predictable pattern, at an overall mean rate of 0.18 mm per year (0.02 to 2.16), but with a mean rate of 0.80 mm (0.02 to 2.5) during the first year. The mean total subsidence was 1.95 mm (0.21 to 24). Only three stems loosened at the cement-bone interface. There was excellent preservation of proximal femoral bone stock. There was a high incidence of Brooker III and IV heterotopic ossification affecting 25 patients (22%). The collarless
Aims. The aim of this large registry-based study was to compare mid-term survival rates of cemented femoral stems of different designs used in hemiarthroplasty for a fracture of the femoral neck. Patients and Methods. From the Norwegian Hip Fracture Register (NHFR), 20 532 primary cemented bipolar hemiarthroplasties, which were undertaken in patients aged > 70 years with a femoral neck fracture between 2005 and 2016, were included. Polished tapered stems (n = 12 065) (Exeter and CPT), straight stems (n = 5545) (Charnley, Charnley Modular, and Spectron EF), and anatomical stems (n = 2922) (Lubinus SP2) were included. The survival of the implant with any reoperation as the endpoint was calculated using the Kaplan–Meier method and hazard ratios (HRs), and the different indications for reoperation were calculated using Cox regression analysis. Results. The one-year survival was 96.0% (95% confidence interval (CI) 95.6 to 96.4) for the Exeter stem, 97.0% (95% CI 96.4 to 97.6) for the Lubinus SP2 stem, 97.6% (95% CI 97.0 to 98.2) for the Charnley stem, 98.1% (95% CI 97.3 to 98.9) for the Spectron EF stem, and 96.4% (95% CI 95.6 to 97.2) for the Charnley Modular stem, respectively. The hazard ratio for reoperation after one year was lower for Lubinus SP2 (HR 0.77, 95% CI 0.60 to 0.97), Charnley (HR 0.64, 95% CI 0.48 to 0.86), and Spectron EF stems (HR 0.44, 95% CI 0.29 to 0.67) compared with the Exeter stem. Reoperation for periprosthetic fracture occurred almost exclusively after the use of
We prospectively followed 191 consecutive collarless
polished tapered (CPT) femoral stems, implanted in 175 patients
who had a mean age at operation of 64.5 years (21 to 85). At a mean
follow-up of 15.9 years (14 to 17.5), 86 patients (95 hips) were
still alive. The fate of all original stems is known. The 16-year
survivorship with re-operation for any reason was 80.7% (95% confidence
interval 72 to 89.4). There was no loss to follow-up, with clinical
data available on all 95 hips and radiological assessment performed
on 90 hips (95%). At latest follow-up, the mean Harris hip score
was 78 (28 to 100) and the mean Oxford hip score was 36 (15 to 48).
Stems subsided within the cement mantle, with a mean subsidence
of 2.1 mm (0.4 to 19.2). Among the original cohort, only one stem
(0.5%) has been revised due to aseptic loosening. In total seven
stems were revised for any cause, of which four revisions were required
for infection following revision of the acetabular component. A
total of 21 patients (11%) required some sort of revision procedure;
all except three of these resulted from failure of the acetabular
component. Cemented acetabular components had a significantly lower
revision burden (three hips, 2.7%) than Harris Galante uncemented
components (17 hips, 21.8%) (p <
0.001). The CPT stem continues to provide excellent radiological and
clinical outcomes at 15 years following implantation. Its results
are consistent with other
This aim of this study was to assess the reliability and validity of the Unified Classification System (UCS) for postoperative periprosthetic femoral fractures (PFFs) around cemented polished taper-slip (PTS) stems. Radiographs of 71 patients with a PFF admitted consecutively at two centres between 25 February 2012 and 19 May 2020 were collated by an independent investigator. Six observers (three hip consultants and three trainees) were familiarized with the UCS. Each PFF was classified on two separate occasions, with a mean time between assessments of 22.7 days (16 to 29). Interobserver reliability for more than two observers was assessed using percentage agreement and Fleiss’ kappa statistic. Intraobserver reliability between two observers was calculated with Cohen kappa statistic. Validity was tested on surgically managed UCS type B PFFs where stem stability was documented in operation notes (n = 50). Validity was assessed using percentage agreement and Cohen kappa statistic between radiological assessment and intraoperative findings. Kappa statistics were interpreted using Landis and Koch criteria. All six observers were blinded to operation notes and postoperative radiographs.Aims
Methods
This was a safety study where the hypothesis was that the newer-design CPCS femoral stem would demonstrate similar early clinical results and micromovement to the well-established Exeter stem. Both are collarless, tapered,
The Unified Classification System (UCS), or Vancouver system, is a validated and widely used classification system to guide the management of periprosthetic femoral fractures. It suggests that well-fixed stems (type B1) can be treated with fixation but that loose stems (types B2 and B3) should be revised. Determining whether a stem is loose can be difficult and some authors have questioned how to apply this classification system to polished taper slip stems which are, by definition, loose within their cement mantle. Recent evidence has challenged the common perception that revision surgery is preferable to fixation surgery for UCS-B periprosthetic fractures around cemented polished taper slip stems. Indications for fixation include an anatomically reducible fracture and cement mantle, a well-fixed femoral bone-cement interface, and a well-functioning acetabular component. However, not all type B fractures can or should be managed with fixation due to the risk of early failure. This annotation details specific fracture patterns that should not be managed with fixation alone. Cite this article:
Femoral impaction bone allografting has been developed as a means of restoring bone stock in revision total hip replacement. We report the results of 75 consecutive patients (75 hips) with a mean age of 68 years (35 to 87) who underwent impaction grafting using the Exeter collarless, polished, tapered femoral stem between 1992 and 1998. The mean follow-up period was 10.5 years (6.3 to 14.1). The median pre-operative bone defect score was 3 (interquartile range (IQR) 2 to 3) using the Endo-Klinik classification. The median subsidence at one year post-operatively was 2 mm (IQR 1 to 3). At the final review the median Harris hip score was 80.6 (IQR 67.6 to 88.9) and the median subsidence 2 mm (IQR 1 to 4). Incorporation of the allograft into trabecular bone and secondary remodelling were noted radiologically at the final follow-up in 87% (393 of 452 zones) and 40% (181 of 452 zones), respectively. Subsidence of the Exeter stem correlated with the pre-operative Endo-Klinik bone loss score (p = 0.037). The degree of subsidence at one year had a strong association with long-term subsidence (p <
0.001). There was a significant correlation between previous revision surgery and a poor Harris Hip score (p = 0.028), and those who had undergone previous revision surgery for infection had a higher risk of complications (p = 0.048). Survivorship at 10.5 years with any further femoral operation as the end-point was 92% (95% confidence interval 82 to 97).
Aims. Highly
We have compared prospectively the incidence of loosening of 20 femoral stems with a matt surface with that of 20
Aims. The aim of this study was to compare the design of the generic
OptiStem XTR femoral stem with the established Exeter femoral stem. Materials and Methods. We obtained five boxed, as manufactured, implants of both designs
at random (ten in total). Two examiners were blinded to the implant
design and independently measured the mass, volume, trunnion surface
topography, trunnion roughness, trunnion cone angle, Caput-Collum-Diaphyseal
(CCD) angle, femoral offset, stem length, neck length, and the width
and roughness of the
Aims. Femoral impaction bone grafting was first developed in 1987 using
morselised cancellous bone graft impacted into the femoral canal
in combination with a cemented, tapered,
Aims. Debate continues about whether it is better to use a cemented or uncemented hemiarthroplasty to treat a displaced intracapsular fracture of the hip. The aim of this study was to attempt to resolve this issue for contemporary prostheses. Methods. A total of 400 patients with a displaced intracapsular fracture of the hip were randomized to receive either a cemented
The aim of this study was to report the three-year follow-up for a series of 400 patients with a displaced intracapsular fracture of the hip, who were randomized to be treated with either a cemented polished tapered hemiarthroplasty or an uncemented hydroxyapatite-coated hemiarthroplasty. The mean age of the patients was 85 years (58 to 102) and 273 (68%) were female. Follow-up was undertaken by a nurse who was blinded to the hemiarthroplasty that was used, at intervals for up to three years from surgery. The short-term follow-up of these patients at a mean of one year has previously been reported.Aims
Methods
The Exeter femoral stem has a cemented, polished taper-slip design, and an excellent track record. The current range includes short-length options for various offsets, but less is known about the performance of these stems. The aim of this study was to compare the survival of short-length stems with standard-length Exeter stems. A systematic review of all studies reporting the use of short-length Exeter stems in primary total hip arthroplasty (THA) was undertaken. Survival data, the indication for revision, and patient-reported outcomes were gathered from observational and randomized studies. Studies based on registry data were analyzed separately.Aims
Methods
We studied the effect of the surface finish of the stem on the transfer of load in the proximal femur in a sheep model of cemented hip arthroplasty. Strain-gauge analysis and corresponding finite-element (FE) analysis were performed to assess the effect of friction and creep at the cement-stem interface. No difference was seen between the matt and
We describe the results of 81 consecutive revision
total hip replacements with impaction grafting in 79 patients using
a collared
We have prospectively studied the wear of enhanced ultra-high molecular-weight polyethylene (Hylamer) in combination with a zirconia femoral head of 22.225 mm diameter on a cemented, triple-tapered, collarless,
It has been suggested that the endurance of cemented femoral reconstructions in total hip arthroplasty is affected by the creep of acrylic cement, but it is not known to what extent cement creeps under loading conditions in vivo, or how this affects load transfer. We have simulated the long-term creep properties of acrylic cement in finite-element models of femoral stem constructs and analysed their effects. We investigated whether subsidence rates measured in vivo could be explained by creep of acrylic cement, and if
Polished taper-slip (PTS) cemented stems have an excellent clinical track record and are the most common stem type used in primary total hip arthroplasty (THA) in the UK. Due to low rates of aseptic loosening, they have largely replaced more traditional composite beam (CB) cemented stems. However, there is now emerging evidence from multiple joint registries that PTS stems are associated with higher rates of postoperative periprosthetic femoral fracture (PFF) compared to their CB stem counterparts. The risk of both intraoperative and postoperative PFF remains greater with uncemented stems compared to either of these cemented stem subtypes. PFF continues to be a devastating complication following primary THA and is associated with high complication and mortality rates. Recent efforts have focused on identifying implant-related risk factors for PFF in order to guide preventative strategies, and therefore the purpose of this article is to present the current evidence on the effect of cemented femoral stem design on the risk of PFF. Cite this article:
Several different designs of hemiarthroplasty are used to treat intracapsular fractures of the proximal femur, with large variations in costs. No clinical benefit of modular over monoblock designs has been reported in the literature. Long-term data are lacking. The aim of this study was to report the ten-year implant survival of commonly used designs of hemiarthroplasty. Patients recorded by the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) between 1 September 1999 and 31 December 2020 who underwent hemiarthroplasty for the treatment of a hip fracture with the following implants were included: a cemented monoblock Exeter Trauma Stem (ETS), cemented Exeter V40 with a bipolar head, a monoblock Thompsons prosthesis (Cobalt/Chromium or Titanium), and an Exeter V40 with a Unitrax head. Overall and age-defined cumulative revision rates were compared over the ten years following surgery.Aims
Methods
The aim of this study was to compare open reduction and internal fixation (ORIF) with revision surgery for the surgical management of Unified Classification System (UCS) type B periprosthetic femoral fractures around cemented polished taper-slip femoral components following primary total hip arthroplasty (THA). Data were collected for patients admitted to five UK centres. The primary outcome measure was the two-year reoperation rate. Secondary outcomes were time to surgery, transfusion requirements, critical care requirements, length of stay, two-year local complication rates, six-month systemic complication rates, and mortality rates. Comparisons were made by the form of treatment (ORIF vs revision) and UCS type (B1 vs B2/B3). Kaplan-Meier survival analysis was performed with two-year reoperation for any reason as the endpoint.Aims
Methods
The aim of this study was to describe the demographic details of patients who sustain a femoral periprosthetic fracture (PPF), the epidemiology of PPFs, PPF characteristics, and the predictors of PPF types in the UK population. This is a multicentre retrospective cohort study including adult patients presenting to hospital with a new PPF between 1 January 2018 and 31 December 2018. Data collected included: patient characteristics, comorbidities, anticoagulant use, social circumstances, level of mobility, fracture characteristics, Unified Classification System (UCS) type, and details of the original implant. Descriptive analysis by fracture location was performed, and predictors of PPF type were assessed using mixed-effects logistic regression models.Aims
Methods
Femoral cement-in-cement revision is a well described technique to reduce morbidity and complications in hip revision surgery. Traditional techniques for septic revision of hip arthroplasty necessitate removal of all bone cement from the femur. In our two centres, we have been using a cement-in-cement technique, leaving the distal femoral bone cement in selected patients for septic hip revision surgery, both for single and the first of two-stage revision procedures. A prerequisite for adoption of this technique is that the surgeon considers the cement mantle to be intimately fixed to bone without an intervening membrane between cement and host bone. We aim to report our experience for this technique. We have analyzed patients undergoing this cement-in-cement technique for femoral revision in infection, and present a consecutive series of 89 patients. Follow-up was undertaken at a mean of 56.5 months (24.0 to 134.7) for the surviving cases.Aims
Methods
There is a paucity of long-term studies analyzing risk factors for failure after single-stage revision for periprosthetic joint infection (PJI) following total hip arthroplasty (THA). We report the mid- to long-term septic and non-septic failure rate of single-stage revision for PJI after THA. We retrospectively reviewed 88 cases which met the Musculoskeletal Infection Society (MSIS) criteria for PJI. Mean follow-up was seven years (1 to 14). Septic failure was diagnosed with a Delphi-based consensus definition. Any reoperation for mechanical causes in the absence of evidence of infection was considered as non-septic failure. A competing risk regression model was used to evaluate factors associated with septic and non-septic failures. A Kaplan-Meier estimate was used to analyze mortality.Aims
Methods
The aim of this study was to determine whether fixation, as opposed to revision arthroplasty, can be safely used to treat reducible Vancouver B type fractures in association with a cemented collarless polished tapered femoral stem (the Exeter). This retrospective cohort study assessed 152 operatively managed consecutive unilateral Vancouver B fractures involving Exeter stems; 130 were managed with open reduction and internal fixation (ORIF) and 22 with revision arthroplasty. Mean follow-up was 6.5 years (SD 2.6; 3.2 to 12.1). The primary outcome measure was revision of at least one component. Kaplan–Meier survival analysis was performed. Regression analysis was used to identify risk factors for revision following ORIF. Secondary outcomes included any reoperation, complications, blood transfusion, length of hospital stay, and mortality.Aims
Methods
We report the clinical and radiographic outcomes
of 208 consecutive femoral revision arthroplasties performed in 202
patients (119 women, 83 men) between March 1991 and December 2007
using the X-change Femoral Revision System, fresh-frozen morcellised
allograft and a cemented
We aimed to report the mid- to long-term rates of septic and aseptic failure after two-stage revision surgery for periprosthetic joint infection (PJI) following total hip arthroplasty (THA). We retrospectively reviewed 96 cases which met the Musculoskeletal Infection Society criteria for PJI. The mean follow-up was 90 months (SD 32). Septic failure was assessed using a Delphi-based consensus definition. Any further surgery undertaken for aseptic mechanical causes was considered as aseptic failure. The cumulative incidence with competing risk analysis was used to predict the risk of septic failure. A regression model was used to evaluate factors associated with septic failure. The cumulative incidence of aseptic failure was also analyzed.Aims
Methods
We have evaluated the in vivo migration patterns of 164 primary consecutive Charnley-Kerboull total hip replacements which were undertaken in 155 patients. The femoral preparation included removal of diaphyseal cancellous bone to obtain primary rotational stability of the stem before line-to-line cementing. We used the Ein Bild Roentgen Analyse femoral component method to assess the subsidence of the femoral component. At a mean of 17.3 years (15.1 to 18.3) 73 patients were still alive and had not been revised, eight had been revised, 66 had died and eight had been lost to follow-up. The mean subsidence of the entire series was 0.63 mm (0.0 to 1.94). When using a 1.5 mm threshold, only four stems were considered to have subsided. Our study showed that, in most cases, a highly
Periprosthetic fractures (PPFs) around cemented taper-slip femoral prostheses often result in a femoral component that is loose at the prosthesis-cement interface, but where the cement-bone interface remains well-fixed and bone stock is good. We aim to understand how best to classify and manage these fractures by using a modification of the Vancouver classification. We reviewed 87 PPFs. Each was a first episode of fracture around a cemented femoral component, where surgical management consisted of revision surgery. Data regarding initial injury, intraoperative findings, and management were prospectively collected. Patient records and serial radiographs were reviewed to determine fracture classification, whether the bone cement was well fixed (B2W) or loose (B2L), and time to fracture union following treatment.Aims
Methods
We have tested the axial and torsional stability of femoral components after revision arthroplasty in a cadaver model, using impacted morsellised cancellous graft and cement. Each one of six matched pairs of fresh frozen human femora had either a primary or a revision prosthesis cemented in place. For the ‘revision’ experiments, all cancellous bone was removed from the proximal femur which was then over-reamed to create a smooth-walled cortical shell. An MTS servohydraulic test frame was used to apply axial and torsional loads to each specimen through the prosthetic femoral heads with the femur submerged in isotonic saline solution at 37°C. The mean subsidence was 0.27 ± 0.17 mm for the primary and 0.52 ± 0.30 mm for the revision groups. The difference was statistically significant (p <
0.025), but the mean subsidence was <
1 mm in both groups. The mean maximum torque before failure was 42.9 ± 26.9 N-m for the primary and 34.8± 20.7 N-m for the revision groups. This difference was not statistically significant (p >
0.015). Based on our results we suggest that revision of the femoral component using morsellised cancellous graft followed by cementing with a collarless prosthesis with a
Despite few good-quality studies on the subject, total hip arthroplasty (THA) is increasingly being performed for displaced intracapsular fractures of the neck of femur. We compared outcomes of all patients with displacement of these fractures treated surgically over a ten-year period in one institution. A total of 2,721 patients with intracapsular fractures of the femoral neck treated with either a cemented hemiarthroplasty or a THA at a single centre were retrospectively reviewed. The primary outcomes analyzed were readmission for any reason and revision surgery. We secondarily looked at mortality rates.Aims
Methods
Currently, periprosthetic fractures are excluded from the American Society for Bone and Mineral Research (ASBMR) definition of atypical femoral fracture (AFFs). This study aims to report on a series of periprosthetic femoral fractures (PFFs) that otherwise meet the criteria for AFFs. Secondary aims were to identify predictors of periprosthetic atypical femoral fractures (PAFFs) and quantify the complications of treatment. This was a retrospective case control study of consecutive patients with periprosthetic femoral fractures between 2007 and 2017. Two observers identified 16 PAFF cases (mean age 73.9 years (44 to 88), 14 female patients) and 17 typical periprosthetic fractures in patients on bisphosphonate therapy as controls (mean age 80.7 years (60 to 86, 13 female patients). Univariate and multivariate analysis was performed to identify predictors of PAFF. Management and complications were recorded.Aims
Patients and Methods
Recent guidance recommends the use of a well-proven
cemented femoral stem for hemiarthroplasty in the management of
fractures of the femoral neck, and the Exeter Trauma Stem (ETS)
has been suggested as an example of such an implant. The design
of this stem was based on the well-proven Exeter Total Hip Replacement
stem (ETHRS). This study assessed the surface finish of the ETS
in comparison with the ETHRS. Two ETSs and two ETHRSs were examined
using a profilometer with a precision of 1 nm and compared with
an explanted Exeter Matt stem. The mean roughness average (RA) of
the ETSs was approximately ten times higher than that of the ETHRSs (0.235 μm
(0.095 to 0.452) Cite this article:
We undertook a review of the literature relating to the two basic stem designs in use in cemented hip replacement, namely loaded tapers or force-closed femoral stems, and the composite beam or shape-closed designs. The associated stem fixation theory as understood from It is clear that both design principles are capable of producing successful long-term results, providing that their specific requirements of stem metallurgy, shape and surface finish, preparation of the bone and handling of the cement are observed.
In 2005, we demonstrated that the polished triple-tapered
C-stem at two years had migrated distally and rotated internally.
From that series, 33 patients have now been followed radiologically,
clinically and by radiostereometric analysis (RSA) for up to ten
years. The distal migration within the cement mantle had continued
and reached a mean of 2 mm (0.5 to 4.0) at ten years. Internal rotation,
also within the cement mantle, was a mean 3.8° (external 1.6° to
internal 6.6°) The cement mantle did not show any sign of migration
or loosening in relation to the femoral bone. There were no clinical
or radiological signs indicating that the migration or rotation
within the cement mantle had had any adverse effects for the patients. Cite this article:
This study aimed to compare the change in health-related quality
of life of patients receiving a traditional cemented monoblock Thompson
hemiarthroplasty compared with a modern cemented modular polished-taper
stemmed hemiarthroplasty for displaced intracapsular hip fractures. This was a pragmatic, multicentre, multisurgeon, two-arm, parallel
group, randomized standard-of-care controlled trial. It was embedded
within the WHiTE Comprehensive Cohort Study. The sample size was
964 patients. The setting was five National Health Service Trauma
Hospitals in England. A total of 964 patients over 60 years of age who
required hemiarthroplasty of the hip between February 2015 and March
2016 were included. A standardized measure of health outcome, the
EuroQol (EQ-5D-5L) questionnaire, was carried out on admission and
at four months following the operation.Aims
Patients and Methods
The outcome of 219 revision total hip arthroplasties
(THAs) in 98 male and 121 female patients, using 137 long length
and 82 standard length cemented collarless double-taper femoral
stems in 211 patients, with a mean age of 72 years (30 to 90) and
mean follow-up of six years (two to 18) have been described previously.
We have extended the follow-up to a mean of 13 years (8 to 20) in
this cohort of patients in which the pre-operative bone deficiency Paprosky
grading was IIIA or worse in 79% and 73% of femurs with long and
standard stems, respectively. For the long stem revision group, survival to re-revision for
aseptic loosening at 14 years was 97% (95% confidence interval (CI)
91 to 100) and in patients aged >
70 years, survival was 100%. Two
patients (two revisions) were lost to follow-up and 86 patients
with 88 revisions had died. Worst-case analysis for survival to
re-revision for aseptic loosening at 14 years was 95% (95% CI 89
to 100) and 99% (95% CI 96 to 100) for patients aged >
70 years. One
additional long stem was classified as loose radiographically but
not revised. For the standard stem revision group, survival to re-revision
for aseptic loosening at 14 years was 91% (95% CI 83 to 99). No
patients were lost to follow-up and 49 patients with 51 hips had
died. No additional stems were classified as loose radiographically. Femoral revision using a cemented collarless double-taper stem,
particularly with a long length stem, and in patients aged >
70
years, continues to yield excellent results up to 20 years post-operatively,
including in hips with considerable femoral metaphyseal bone loss. Cite this article:
We reviewed 142 consecutive primary total hip replacements implanted into 123 patients between 1988 and 1993 using the Exeter Universal femoral stem. A total of 74 patients (88 hips) had survived for ten years or more and were reviewed at a mean of 12.7 years (10 to 17). There was no loss to follow-up. The rate of revision of the femoral component for aseptic loosening and osteolysis was 1.1% (1 stem), that for revision for any cause was 2.2% (2 stems), and for re-operation for any cause was 21.6% (19 hips). Re-operation was because of failure of the acetabular component in all but two hips. All but one femoral component subsided within the cement mantle to a mean of 1.52 mm (0 to 8.3) at the final follow-up. One further stem had subsided excessively (8 mm) and had lucent lines at the cement-stem and cement-bone interfaces. This was classified as a radiological failure and is awaiting revision. One stem was revised for deep infection and one for excessive peri-articular osteolysis. Defects of the cement mantle (Barrack grade C and D) were found in 28% of stems (25 hips), associated with increased subsidence (p = 0.01), but were not associated with endosteal lysis or failure. Peri-articular osteolysis was significantly related to the degree of polyethylene wear (p <
0.001), which was in turn associated with a younger age (p = 0.01) and male gender (p <
0.001). The use of the Exeter metal-backed acetabular component was a notable failure with 12 of 32 hips (37.5%) revised for loosening. The Harris-Galante components failed with excessive wear, osteolysis and dislocation with 15% revised (5 of 33 hips). Only one of 23 hips with a cemented Elite component (4%) was revised for loosening and osteolysis. Our findings show that the Exeter Universal stem implanted outside the originating centre has excellent medium-term results.
Periprosthetic fracture (PF) after primary total hip arthroplasty
(THA) is an uncommon but potentially devastating complication. This
study aims to investigate the influence of cemented stem designs
on the risk of needing a revision for a PF. We analysed data on 257 202 primary THAs with cemented stems
and 390 linked first revisions for PF recorded in the National Joint
Registry (NJR) of England, Wales and Northern Ireland to determine
if a cemented femoral stem brand was associated with the risk of
having revision for a PF after primary THA. All cemented femoral
stem brands with more than 10 000 primary operations recorded in
the NJR were identified. The four most commonly used cemented femoral
stems were the Exeter V40 (n = 146 409), CPT (n = 24 300), C-Stem
(n = 15 113) and Charnley (n = 20 182). We compared the revision risk ratios due to PF amongst the stems
using a Poisson regression model adjusting for patient factors.
Compared with the Exeter V40, the age, gender and ASA grade adjusted
revision rate ratio was 3.89 for the cemented CPT stem (95% confidence
interval (CI) 3.07 to 4.93), 0.89 for the C-Stem (95% CI 0.57 to
1.41) and 0.41 for the Charnley stem (95% CI 0.24 to 0.70).Aims
Patients and Methods
We describe our technique and rationale using
hybrid fixation for primary total hip arthroplasty (THA) at the Hospital
for Special Surgery. Modern uncemented acetabular components have
few screw holes, or no holes, polished inner surfaces, improved
locking mechanisms, and maximised thickness and shell-liner conformity. Uncemented
sockets can be combined with highly cross-linked polyethylene liners,
which have demonstrated very low wear and osteolysis rates after
ten to 15 years of implantation. The results of cement fixation
with a smooth or polished surface finished stem have been excellent,
virtually eliminating complications seen with cementless fixation
like peri-operative femoral fractures and thigh pain. Although mid-term
results of modern cementless stems are encouraging, the long-term
data do not show reduced revision rates for cementless stems compared
with cemented smooth stems. In this paper we review the conduct
of a hybrid THA, with emphasis on pre-operative planning, surgical
technique, hypotensive epidural anaesthesia, and intra-operative
physiology. Cite this article:
We have investigated the role of the penetration of saline on the shear strength of the cement-stem interface for stems inserted at room temperature and those preheated to 37°C using a variety of commercial bone cements. Immersion in saline for two weeks at 37°C reduced interfacial strength by 56% to 88% after insertion at room temperature and by 28% to 49% after preheating of the stem. The reduction in porosity as a result of preheating ranged from 71% to 100%. Increased porosity correlated with a reduction in shear strength after immersion in saline (r = 0.839, p <
0.01) indicating that interfacial porosity may act as a fluid conduit.
Compared with primary total hip arthroplasty (THA), revision
surgery can be challenging. The cement-in-cement femoral revision
technique involves removing a femoral component from a well-fixed
femoral cement mantle and cementing a new stem into the original
mantle. This technique is widely used and when carried out for the
correct indications, is fast, relatively inexpensive and carries
a reduced short-term risk for the patient compared with the alternative
of removing well-fixed cement. We report the outcomes of this procedure
when two commonly used femoral stems are used. We identified 1179 cement-in-cement stem revisions involving
an Exeter or a Lubinus stem reported to the Swedish Hip Arthroplasty
Register (SHAR) between January 1999 and December 2015. Kaplan-Meier
survival analysis was performed.Aims
Patients and Methods
The aim of this study was to investigate the
possible benefit of large-head metal-on-metal bearing on a stem
for primary hip replacement compared with a 28 mm diameter conventional
metal-on-polyethylene bearing in a prospective randomised controlled
trial. We investigated cemented stem behaviour between these two
different bearings using Einzel-Bild-Röntgen-Analyse, clinical and
patient reported measures (Harris hip score, Western Ontario and
McMaster Universities osteoarthritis index, Short Form-36 and satisfaction)
and whole blood metal ion levels at two years. A power study indicated
that 50 hips were needed in each group to detect subsidence of >
5 mm at two years with a
p-value of <
0.05. Significant improvement (p <
0.001) was found in the mean
clinical and patient reported outcomes at two years for both groups.
Comparison of outcomes between the groups at two years showed no
statistically significant difference for mean stem migration, clinical
and patient reported outcomes; except overall patient satisfaction which
was higher for metal-on-metal group (p = 0.05). Metal ion levels
were raised above the Medicines and Healthcare products Regulatory
Agency advised safety level (7 µg per litre) in 20% of the metal-on-metal
group and in one patient in metal-on-polyethylene group (who had
a metal-on-metal implant on the contralateral side). Two patients
in the metal-on-metal group were revised, one for pseudotumour and
one for peri-prosthetic fracture. Use of large modular heads is associated with a risk of raised
whole blood metal ion levels despite using a proven bearing from
resurfacing. The head-neck junction or excess stem micromotion are
possibly the weak links warranting further research.
The removal of well-fixed bone cement from the femoral canal during revision of a total hip replacement (THR) can be difficult and risks the loss of excessive bone stock and perforation or fracture of the femoral shaft. Retaining the cement mantle is attractive, yet the technique of cement-in-cement revision is not widely practised. We have used this procedure at our hospital since 1989. The stems were removed to gain a better exposure for acetabular revision, to alter version or leg length, or for component incompatibility. We studied 136 hips in 134 patients and followed them up for a mean of eight years (5 to 15). A further revision was required in 35 hips (25.7%), for acetabular loosening in 26 (19.1%), sepsis in four, instability in three, femoral fracture in one and stem fracture in one. No femoral stem needed to be re-revised for aseptic loosening. A cement-in-cement revision of the femoral stem is a reliable technique in the medium term. It also reduces the risk of perforation or fracture of the femoral shaft.