The mechanical performance of the cement-in-cement interface in revision surgery has not been fully investigated. The quantitative effect posed by interstitial fluids and roughening of the primary mantle remains unclear. We have analysed the strength of the bilaminar cement-bone interface after exposure of the surface of the primary mantle to roughening and fluid interference. The end surfaces of cylindrical blocks of cement were machined smooth (Ra = 200 nm) or rough (Ra = 5 μm) and exposed to either different volumes of water and carboxymethylcellulose (a bone-marrow equivalent) or left
In order to release the contracture band completely without damaging normal tissues (such as the sciatic nerve) in the surgical treatment of gluteal muscle contracture (GMC), we tried to display the relationship between normal tissue and contracture bands by magnetic resonance neurography (MRN) images, and to predesign a minimally invasive surgery based on the MRN images in advance. A total of 30 patients (60 hips) were included in this study. MRN scans of the pelvis were performed before surgery. The contracture band shape and external rotation angle (ERA) of the proximal femur were also analyzed. Then, the minimally invasive GMC releasing surgery was performed based on the images and measurements, and during the operation, incision lengths, surgery duration, intraoperative bleeding, and complications were recorded; the time of the first postoperative off-bed activity was also recorded. Furthermore, the patients’ clinical functions were evaluated by means of Hip Outcome Score (HOS) and Ye et al’s objective assessments, respectively.Aims
Methods
Periprosthetic joint infections (PJIs) with prior multiple failed surgery for reinfection represent a huge challenge for surgeons because of poor vascular supply and biofilm formation. This study aims to determine the results of single-stage revision using intra-articular antibiotic infusion in treating this condition. A retrospective analysis included 78 PJI patients (29 hips; 49 knees) who had undergone multiple prior surgical interventions. Our cohort was treated with single-stage revision using a supplementary intra-articular antibiotic infusion. Of these 78 patients, 59 had undergone more than two prior failed debridement and implant retentions, 12 patients had a failed arthroplasty resection, three hips had previously undergone failed two-stage revision, and four had a failed one-stage revision before their single-stage revision. Previous failure was defined as infection recurrence requiring surgical intervention. Besides intravenous pathogen-sensitive agents, an intra-articular infusion of vancomycin, imipenem, or voriconazole was performed postoperatively. The antibiotic solution was soaked into the joint for 24 hours for a mean of 16 days (12 to 21), then extracted before next injection. Recurrence of infection and clinical outcomes were evaluated.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
The aim of this study was to identify the minimal clinically important difference (MCID), minimal important change (MIC), minimal detectable change (MDC), and patient-acceptable symptom state (PASS) in the Forgotten Joint Score (FJS) according to patient satisfaction six months following total hip arthroplasty (THA) in a UK population. During a one-year period, 461 patients underwent a primary THA and completed preoperative and six-month FJS, with a mean age of 67.2 years (22 to 93). At six months, patient satisfaction was recorded as very satisfied, satisfied, neutral, dissatisfied, or very dissatisfied. The difference between patients recording neutral (n = 31) and satisfied (n = 101) was used to define the MCID. MIC for a cohort was defined as the change in the FJS for those patients declaring their outcome as satisfied, whereas receiver operating characteristic curve analysis was used to determine the MIC for an individual and the PASS. Distribution-based methodology was used to calculate the MDC.Aims
Methods
This study investigates head-neck taper corrosion with varying head size in a novel hip simulator instrumented to measure corrosion related electrical activity under torsional loads. In all, six 28 mm and six 36 mm titanium stem-cobalt chrome head pairs with polyethylene sockets were tested in a novel instrumented hip simulator. Samples were tested using simulated gait data with incremental increasing loads to determine corrosion onset load and electrochemical activity. Half of each head size group were then cycled with simulated gait and the other half with gait compression only. Damage was measured by area and maximum linear wear depth.Aims
Methods
To evaluate the effect of ultrasound-targeted simvastatin-loaded microbubble destruction (UTMD In vitro, OA chondrocytes were treated with ultrasound (US), US-targeted microbubble destruction (UTMD), simvastatin (SV), and UTMDAims
Methods
The aim of this study was to perform a cross-cultural adaptation of Oxford Hip Score (OHS) to Indonesian, and to evaluate its psychometric properties. We performed a cross-cultural adaptation of Oxford Hip Score into Indonesian language (OHS-ID) and determined its internal consistency, test-retest reliability, measurement error, floor-ceiling effect, responsiveness, and construct validity by hypotheses testing of its correlation with Harris Hip Score (HHS), vsual analogue scale (VAS), and Short Form-36 (SF-36). Adults (> 17 years old) with chronic hip pain (osteoarthritis or osteonecrosis) were included.Aims
Methods
To achieve the functional benefits of the direct anterior (DA) approach and the fixation benefits of cemented replacement, this study combined the two techniques posing the following questions: does the limited access of the DA approach adversely affect the cement technique?; and does such a cementing technique reduce the incidence of cementless complications? A consecutive series of 341 patients (360 hips) receiving the DA approach between 2016 and 2018 were reviewed. There were 203 cementless stems and 157 cemented stems. Mean age was 75 years (70 to 86) in the cementless group and 76 years (52 to 94) in the cemented group, with 239 (70%) females in the whole series. Femoral complications were compared between the two groups. Mean follow-up was 1.5 years (0.1 to 4.4) for patients in the cementless group and 1.3 years (0.0 to 3.9) for patients in the cemented group.Aims
Methods
The aims of this study were to develop an in vivo model of periprosthetic joint infection (PJI) in cemented hip hemiarthroplasty, and to monitor infection and biofilm formation in real-time. Sprague-Dawley rats underwent cemented hip hemiarthroplasty via the posterior approach with pre- and postoperative gait assessments. Infection with Aims
Methods
Cement-in-cement revision of the femoral component represents a widely practised technique for a variety of indications in revision total hip arthroplasty. In this study, we compare the clinical and radiological outcomes of two polished tapered femoral components. From our prospectively collated database, we identified all patients undergoing cement-in-cement revision from January 2005 to January 2013 who had a minimum of two years' follow-up. All cases were performed by the senior author using either an Exeter short revision stem or the C-Stem AMT high offset No. 1 prosthesis. Patients were followed-up annually with clinical and radiological assessment.Aims
Methods
The purpose of this study was to evaluate unexpected positive cultures in total hip arthroplasty (THA) revisions for presumed aseptic loosening, to assess the prevalence of low-grade infection using two definition criteria, and to analyze its impact on implant survival after revision. A total of 274 THA revisions performed for presumed aseptic loosening from 2012 to 2016 were reviewed. In addition to obtaining intraoperative tissue cultures from all patients, synovial and sonication fluid samples of the removed implant were obtained in 215 cases (79%) and 101 cases (37%), respectively. Histopathological analysis was performed in 250 cases (91%). Patients were classified as having low-grade infections according to institutional criteria and Musculoskeletal Infection Society (MSIS) International Consensus Meeting (ICM) 2013 criteria. Low-grade infections according to institutional criteria were treated with targeted antibiotics for six weeks postoperatively. Implant failure was defined as the need for re-revision resulting from periprosthetic joint infection (PJI) and aseptic reasons. The mean follow-up was 68 months (26 to 95).Aims
Methods
Of growing concern in arthroplasty is the emergence of atypical infections, particularly For this non-randomized non-blinded study, 101 adult patients scheduled for hip or knee surgery were recruited. For each, four 3 mm dermal punch biopsies were collected after administration of anaesthesia, but prior to antibiotics. Prebiopsy skin preparation consisted of a standardized preoperative 2% chlorhexidine skin cleansing protocol and an additional 70% isopropyl alcohol mechanical skin scrub immediately prior to biopsy collection. Two skin samples 10 cm apart were collected from a location approximating a standard direct anterior skin incision, and two samples 10 cm apart were collected from a lateral skin incision (suitable for posterior, direct-lateral, or anterolateral approaches). Samples were cultured for two weeks using a protocol optimized for Aims
Methods
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
Previous studies have evidenced cement-in-cement techniques as reliable in revision arthroplasty. Commonly, the original cement mantle is reshaped, aiding accurate placement of the new stem. Ultrasonic devices selectively remove cement, preserve host bone, and have lower cortical perforation rates than other techniques. As far as the authors are aware, the impact of ultrasonic devices on final cement-in-cement bonds has not been investigated. This study assessed the impact of cement removal using the Orthosonics System for Cemented Arthroplasty Revision (OSCAR; Orthosonics) on final cement-in-cement bonds. A total of 24 specimens were manufactured by pouring cement (Simplex P Bone Cement; Stryker) into stainless steel moulds, with a central rod polished to Stryker Exeter V40 specifications. After cement curing, the rods were removed and eight specimens were allocated to each of three internal surface preparation groups: 1) burr; 2) OSCAR; and 3) no treatment. Internal holes were recemented, and each specimen was cut into 5 mm discs. Shear testing of discs was completed by a technician blinded to the original grouping, recording ultimate shear strengths. Scanning electron microscopy (SEM) was completed, inspecting surfaces of shear-tested specimens.Objectives
Methods
This study presents the long-term survivorship, risk factors for prosthesis survival, and an assessment of the long-term effects of changes in surgical technique in a large series of patients treated by metal-on-metal (MoM) hip resurfacing arthroplasty (HRA). Between November 1996 and January 2012, 1074 patients (1321 hips) underwent HRA using the Conserve Plus Hip Resurfacing System. There were 787 men (73%) and 287 women (27%) with a mean age of 51 years (14 to 83). The underlying pathology was osteoarthritis (OA) in 1003 (75.9%), developmental dysplasia of the hip (DDH) in 136 (10.3%), avascular necrosis in 98 (7.4%), and other conditions, including inflammatory arthritis, in 84 (6.4%).Aims
Patients and Methods
The increasing infection burden after total hip arthroplasty (THA) has seen a rise in the use of two-stage exchange arthroplasty and the use of increasingly powerful antibiotics at the time of this procedure. As a result, there has been an increase in the number of failed two-stage revisions during the past decade. The aim of this study was to clarify the outcome of repeat two-stage revision THA following a failed two-stage exchange due to recurrent prosthetic joint infection (PJI). We identified 42 patients who underwent a two-stage revision THA having already undergone at least one previous two stage procedure for infection, between 2000 and 2015. There were 23 women and 19 men. Their mean age was 69.3 years (48 to 81). The outcome was analyzed at a minimum follow-up of two years.Aims
Patients and Methods
This study reports the mid-term results of total hip arthroplasty (THA) performed using a monoblock acetabular component with a large-diameter head (LDH) ceramic-on-ceramic (CoC) bearing. Of the 276 hips (246 patients) included in this study, 264 (96%) were reviewed at a mean of 67 months (48 to 79) postoperatively. Procedures were performed with a mini posterior approach. Clinical and radiological outcomes were recorded at regular intervals. A noise assessment questionnaire was completed at last follow-up.Aims
Patients and Methods
To present a surgically relevant update of trunnionosis. Systematic review performed April 2017.Aims
Materials and Methods
The management of acetabular defects at the time of revision hip arthroplasty surgery is a challenge. This study presents the results of a long-term follow-up study of the use of irradiated allograft bone in acetabular reconstruction. Between 1990 and 2000, 123 hips in 110 patients underwent acetabular reconstruction for aseptic loosening, using impaction bone grafting with frozen, irradiated, and morsellized femoral heads and a cemented acetabular component. A total of 55 men and 55 women with a mean age of 64.3 years (26 to 97) at the time of revision surgery are included in this study.Aims
Patients and Methods
The injured anterior cruciate ligament (ACL) is thought to exhibit an impaired healing response, and attempts at surgical repair have not been successful. Connective tissue growth factor (CTGF) is reported to be associated with wound healing, probably through transforming growth factor beta 1 (TGF-β1). A rabbit ACL injury model was used to study the effect of CTGF on ligament recovery. Quantitative real-time PCR (qRT-PCR) was performed for detection of changes in RNA levels of TGF-β1, type 1 collagen (COL1), type 2 collagen (COL2), SRY-related high mobility group-box gene9 (SOX9), tissue inhibitor of metalloproteinase-1 (TIMP-1) and matrix metallopeptidase 13 (MMP-13). Expression of related proteins was detected by Western blotting.Objectives
Methods
We present the clinical and radiological results at a minimum
follow-up of five years for patients who have undergone multiple
cement-in-cement revisions of their femoral component at revision
total hip arthroplasty (THA). We reviewed the outcome on a consecutive series of 24 patients
(10 men, 14 women) (51 procedures) who underwent more than one cement-in-cement
revision of the same femoral component. The mean age of the patients was
67.5 years (36 to 92) at final follow-up. Function was assessed using the original Harris hip score (HHS),
Oxford Hip Score (OHS) and the Merle D’Aubigné Postel score (MDP).Aims
Patients and Methods
The classical longitudinal incision used for the direct anterior
approach (DAA) to the hip does not follow the tension lines of the
skin and can lead to impaired wound healing and poor cosmesis. The
purpose of this retrospective study was to determine the satisfaction
with the scar, and functional and radiographic outcomes comparing
the classic longitudinal incision with a modified skin crease ‘bikini’
when the DAA is used for total hip arthroplasty (THA). A total of 964 patients (51% female; 59% longitudinal, 41% ‘bikini’)
completed a follow-up questionnaire between two and four years postoperatively,
including the Oxford Hip Score (OHS), the University of North Carolina
‘4P’ scar scale (UNC4P) and two items for assessing the aesthetic
appearance of the scar and symptoms of numbness. The positioning
of the components, rates of heterotopic ossification (HO) and rates
of revision were assessed.Aims
Patients and Methods
Hip resurfacing arthroplasty (HRA) is an alternative to conventional
total hip arthroplasty for patients with osteonecrosis (ON) of the
femoral head. Our aim was to report the long-term outcome of HRA,
which is not currently known. Long-term survivorship, clinical scores and radiographic results
for 82 patients (99 hips) treated with HRA for ON over a period
of 18 years were reviewed retrospectively. The mean age of the 67
men and 15 women at the time of surgery was 40.8 years (14 to 64).
Patients were resurfaced regardless of the size of the osteonecrotic
lesion.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:
Studies reporting specifically on squeaking in total hip arthroplasty have focused on cementless, and not on hybrid, fixation. We hypothesised that the cement mantle of the femur might have a damping effect on the sound transmitted through the metal stem. The objective of this study was to test the effect of cement on sound propagation along different stem designs and under different fixation conditions. An Objectives
Methods
The use of ceramic femoral heads in total hip arthroplasty (THA) has increased due to their proven low bearing wear characteristics. Ceramic femoral heads are also thought to reduce wear and corrosion at the head-stem junction with titanium (Ti) stems when compared with metal heads. We sought to evaluate taper damage of ceramic compared with metal heads when paired with cobalt chromium (CoCr) alloy stems in a single stem design. This retrieval study involved 48 total hip arthroplasties (THAs) with CoCr V40 trunnions paired with either CoCr (n = 21) or ceramic (n = 27) heads. The taper junction of all hips was evaluated for fretting/corrosion damage and volumetric material loss using a roundness-measuring machine. We used linear regression analysis to investigate taper damage differences after adjusting for potential confounding variables.Objectives
Methods
To analyse the effectiveness of debridement and implant retention
(DAIR) in patients with hip periprosthetic joint infection (PJI)
and the relationship to patient characteristics. The outcome was
evaluated in hips with confirmed PJI and a follow-up of not less
than two years. Patients in whom DAIR was performed were identified from our
hip arthroplasty register (between 2004 and 2013). Adherence to
criteria for DAIR was assessed according to a previously published
algorithm.Aims
Patients and Methods
We present a minimum 20-year follow-up study of 382 cemented
Exeter Universal total hip arthroplasties (350 patients) operated
on at a mean age of 66.3 years (17 to 94). All patients received the same design of femoral component, regardless
of the original diagnosis. Previous surgery had been undertaken
for 33 hips (8.6%). During the study period 218 patients with 236
hips (62%) died, 42 hips (11%) were revised and 110 hips (29%) in
96 patients were available for review. The acetabular components
were varied and some designs are now obsolete, however they were
all cemented.Aims
Patients and Methods
We developed a method of applying vibration to the impaction bone grafting process and assessed its effect on the mechanical properties of the impacted graft. Washed morsellised bovine femoral heads were impacted into shear test rings. A range of frequencies of vibration was tested, as measured using an accelerometer housed in a vibration chamber. Each shear test was repeated at four different normal loads to generate stress-strain curves. The Mohr-Coulomb failure envelope from which shear strength and interlocking values are derived was plotted for each test. The experiments were repeated with the addition of blood in order to replicate a saturated environment. Graft impacted with the addition of vibration at all frequencies showed improved shear strength when compared with impaction without vibration, with 60 Hz giving the largest effect. Under saturated conditions the addition of vibration was detrimental to the shear strength of the aggregate. The civil-engineering principles of particulate settlement and interlocking also apply to impaction bone grafting. Although previous studies have shown that vibration may be beneficial in impaction bone grafting on the femoral side, our study suggests that the same is not true in acetabular revision.
We report on the outcome of the Exeter Contemporary flanged cemented
all-polyethylene acetabular component with a mean follow-up of 12
years (10 to 13.9). This study reviewed 203 hips in 194 patients.
129 hips in 122 patients are still A retrospective review was undertaken of a consecutive series
of 203 routine primary cemented total hip arthroplasties (THA) in
194 patients.Aims
Patients and Methods
The highly cross-linked polyethylene Exeter RimFit flanged cemented
acetabular component was introduced in the United Kingdom in 2010.
This study aimed to examine the rates of emergence of radiolucent
lines observed when the Rimfit acetabular component was implanted
at total hip arthroplasty (THA) using two different techniques: firstly,
the ‘rimcutter’ technique in which the flange sits on a pre-prepared
acetabular rim; and secondly, the ‘trimmed flange’ technique in
which the flange is trimmed and the acetabular component is seated
inside the rim of the acetabulum. The radiographs of 150 THAs (75 ‘rimcutter’, 75 ‘trimmed flange’)
involving this component were evaluated to assess for radiolucencies
at the cement/bone interface by three observers. Aims
Patients and Methods
Sagittal alignment of the lumbosacral spine, and specifically pelvic incidence (PI), has been implicated in the development of spine pathology, but generally ignored with regards to diseases of the hip. We aimed to determine if increased PI is correlated with higher rates of hip osteoarthritis (HOA). The effect of PI on the development of knee osteoarthritis (KOA) was used as a negative control. We studied 400 well-preserved cadaveric skeletons ranging from 50 to 79 years of age at death. Each specimen’s OA of the hip and knee were graded using a previously described method. PI was measured from standardised lateral photographs of reconstructed pelvises. Multiple regression analysis was performed to determine the relationship between age and PI with HOA and KOA.Objectives
Methods
The primary aim of this study was to investigate the effect of
an enhanced recovery program (ERP) on the short-term functional
outcome after total hip arthroplasty (THA). Secondary outcomes included
its effect on rates of dislocation and mortality. Data were gathered on 1161 patients undergoing primary THA which
included 611 patients treated with traditional rehabilitation and
550 treated with an ERP. Aims
Patients and Methods
Revision of a cemented hemiarthroplasty of the
hip may be a hazardous procedure with high rates of intra-operative complications.
Removing well-fixed cement is time consuming and risks damaging
already weak bone or perforating the femoral shaft. The cement-in-cement
method avoids removal of intact cement and has shown good results
when used for revision total hip arthroplasty (THA). The use of
this technique for the revision of a hemiarthroplasty to THA has
not been previously reported. A total of 28 consecutive hemiarthroplasties (in 28 patients)
were revised to a THA using an Exeter stem and the cement-in-cement
technique. There were four men and 24 women; their mean age was
80 years (35 to 93). Clinical and radiographic data, as well as
operative notes, were collected prospectively and no patient was
lost to follow-up. Four patients died within two years of surgery. The mean follow
up of the remainder was 70 months (25 to 124). Intra-operatively
there was one proximal perforation, one crack of the
femoral calcar and one acetabular fracture. No femoral components
have required subsequent revision for aseptic loosening or are radiologically loose. Four patients with late complications (14%) have since undergone
surgery (two for a peri-prosthetic fracture, and one each for deep
infection and recurrent dislocation) resulting in an overall major
rate of complication of 35.7%. The cement-in-cement technique provides reliable femoral fixation
in this elderly population and may reduce operating time and rates
of complication. Cite this article:
This study compared the primary stability of two commercially
available acetabular components from the same manufacturer, which
differ only in geometry; a hemispherical and a peripherally enhanced
design (peripheral self-locking (PSL)). The objective was to determine
whether altered geometry resulted in better primary stability. Acetabular components were seated with 0.8 mm to 2 mm interference
fits in reamed polyethylene bone substrate of two different densities
(0.22 g/cm3 and 0.45 g/cm3). The primary stability
of each component design was investigated by measuring the peak
failure load during uniaxial pull-out and tangential lever-out tests.Objective
Methods
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 modular neck tapers were determined using high resolution
tactile measurements. A new algorithm was developed and validated
to allow the quantitative analysis of material loss, complementing
the standard visual inspection currently used. The algorithm was applied to a sample of 27 retrievals ( Cite this article:
A common situation presenting to the orthopaedic
surgeon today is a worn acetabular liner with substantial acetabular
and pelvic osteolysis. The surgeon has many options for dealing
with osteolytic defects. These include allograft, calcium based
substitutes, demineralised bone matrix, or combinations of these
options with or without addition of platelet rich plasma. To date
there are no clinical studies to determine the efficacy of using
bone-stimulating materials in osteolytic defects at the time of
revision surgery and there are surprisingly few studies demonstrating
the clinical efficacy of these treatment options. Even when radiographs
appear to demonstrate incorporation of graft material CT studies
have shown that incorporation is incomplete. The surgeon, in choosing
a graft material for a surgical procedure must take into account
the efficacy, safety, cost and convenience of that material. Cite this article:
The aim of this study was to assess the role
of synovial C-reactive protein (CRP) in the diagnosis of chronic periprosthetic
hip infection. We prospectively collected synovial fluid from 89
patients undergoing revision hip arthroplasty and measured synovial
CRP, serum CRP, erythrocyte sedimentation rate (ESR), synovial white
blood cell (WBC) count and synovial percentages of polymorphonuclear
neutrophils (PMN). Patients were classified as septic or aseptic
by means of clinical, microbiological, serum and synovial fluid
findings. The high viscosity of the synovial fluid precluded the
analyses in nine patients permitting the results in 80 patients
to be studied. There was a significant difference in synovial CRP
levels between the septic (n = 21) and the aseptic (n = 59) cohort.
According to the receiver operating characteristic curve, a synovial
CRP threshold of 2.5 mg/l had a sensitivity of 95.5% and specificity
of 93.3%. The area under the curve was 0.96. Compared with serum
CRP and ESR, synovial CRP showed a high diagnostic value. According
to these preliminary results, synovial CRP may be a useful parameter
in diagnosing chronic periprosthetic hip infection. Cite this article:
The aim of this study was to assess the effect
of frictional torque and bending moment on fretting corrosion at
the taper interface of a modular femoral component and to investigate
whether different combinations of material also had an effect. The
combinations we examined were 1) cobalt–chromium (CoCr) heads on
CoCr stems 2) CoCr heads on titanium alloy (Ti) stems and 3) ceramic
heads on CoCr stems. In test 1 increasing torque was imposed by offsetting the stem
in the anteroposterior plane in increments of 0 mm, 4 mm, 6 mm and
8 mm when the torque generated was equivalent to 0 Nm, 9 Nm, 14
Nm and 18 Nm. In test 2 we investigated the effect of increasing the bending
moment by offsetting the application of axial load from the midline
in the mediolateral plane. Increments of offset equivalent to head
+ 0 mm, head + 7 mm and head + 14 mm were used. Significantly higher currents and amplitudes were seen with increasing
torque for all combinations of material. However, Ti stems showed
the highest corrosion currents. Increased bending moments associated
with using larger offset heads produced more corrosion: Ti stems
generally performed worse than CoCr stems. Using ceramic heads did
not prevent corrosion, but reduced it significantly in all loading
configurations. Cite this article:
The technique of femoral cement-in-cement revision
is well established, but there are no previous series reporting its
use on the acetabular side at the time of revision total hip replacement.
We describe the technique and report the outcome of 60 consecutive
acetabular cement-in-cement revisions in 59 patients at a mean follow-up
of 8.5 years (5 to 12). All had a radiologically and clinically
well-fixed acetabular cement mantle at the time of revision. During
the follow-up 29 patients died, but no hips were lost to follow-up.
The two most common indications for acetabular revision were recurrent
dislocation (46, 77%) and to complement femoral revision (12, 20%). Of the 60 hips, there were two cases of aseptic loosening of
the acetabular component (3.3%) requiring re-revision. No other
hip was clinically or radiologically loose (96.7%) at the latest
follow-up. One hip was re-revised for infection, four for recurrent
dislocation and one for disarticulation of a constrained component.
At five years the Kaplan-Meier survival rate was 100% for aseptic
loosening and 92.2% (95% CI 84.8 to 99.6), with revision for any cause
as the endpoint. These results support the use of cement-in-cement revision on
the acetabular side in appropriate cases. Theoretical advantages
include preservation of bone stock, reduced operating time, reduced
risk of complications and durable fixation.
The objective of this study was to explore dimensionality of
the Oxford Hip Score (OHS) and examine whether self-reported pain
and functioning can be distinguished in the form of subscales. This was a secondary data analysis of the UK NHS hospital episode
statistics/patient-reported outcome measures dataset containing
pre-operative OHS scores on 97 487 patients who were undergoing
hip replacement surgery. Objective
Methods
To assess the sustainability of our institutional
bone bank, we calculated the final product cost of fresh-frozen femoral
head allografts and compared these costs with the use of commercial
alternatives. Between 2007 and 2010 all quantifiable costs associated
with allograft donor screening, harvesting, storage, and administration
of femoral head allografts retrieved from patients undergoing elective
hip replacement were analysed. From 290 femoral head allografts harvested and stored as full
(complete) head specimens or as two halves, 101 had to be withdrawn.
In total, 104 full and 75 half heads were implanted in 152 recipients.
The calculated final product costs were €1367 per full head. Compared
with the use of commercially available processed allografts, a saving
of at least €43 119 was realised over four-years (€10 780 per year)
resulting in a cost-effective intervention at our institution. Assuming
a price of between €1672 and €2149 per commercially purchased allograft,
breakeven analysis revealed that implanting between 34 and 63 allografts
per year equated to the total cost of bone banking. Cite this article:
We report the five year outcomes of a two-stage
approach for infected total hip replacement. This is a single-surgeon
experience at a tertiary centre where the more straightforward cases
are treated using single-stage exchange. This study highlights the
vital role of the multidisciplinary team in managing these cases. A total of 125 patients (51 male, 74 female) with a mean age
of 68 years (42 to 78) were reviewed prospectively. Functional status
was assessed using the Harris hip score (HHS). The mean HHS improved
from 38 (6 to 78.5) pre-operatively to 81.2 (33 to 98) post-operatively.
Staphylococcus species were isolated in 85 patients (68%). The rate of control of infection was 96% at five years. In all,
19 patients died during the period of the study. This represented
a one year mortality of 0.8% and an overall mortality of 15.2% at
five years. No patients were lost to follow-up. We report excellent control of infection in a series of complex
patients and infections using a two-stage revision protocol supported
by a multidisciplinary approach. The reason for the high rate of
mortality in these patients is not known. Cite this article:
The Oxford hip score (OHS) is a 12-item questionnaire designed
and developed to assess function and pain from the perspective of
patients who are undergoing total hip replacement (THR). The OHS
has been shown to be consistent, reliable, valid and sensitive to
clinical change following THR. It has been translated into different
languages, but no adequately translated, adapted and validated Danish
language version exists. The OHS was translated and cross-culturally adapted into Danish
from the original English version, using methods based on best-practice
guidelines. The translation was tested for psychometric quality
in patients drawn from a cohort from the Danish Hip Arthroplasty
Register (DHR).Objectives
Methods
This preliminary study evaluates a combination
of bone morphogenetic protein (BMP)-7 and non-vascularised autologous
fibular grafting (AFG) for the treatment of osteonecrosis of the
femoral head. BMP-7/AFG combination was applied in seven pre-collapse femoral
heads (five Steinberg stage II, two stage III) in six patients.
Pre- and post-operative evaluation included clinical (Harris hip
score (HHS), visual analogue scale (VAS) for pain) and radiological
assessment (radiographs, quantitative CT) at a mean follow-up of
4 years (2 to 5.5). A marked improvement of function (mean HHS increase of 49.2)
and decrease of pain level (mean VAS decrease of 5) as well as retention
of the sphericity of the femoral head was noted in five hips at
the latest follow-up, while signs of consolidation were apparent
from the third post-operative month. One patient (two hips) required
bilateral total hip replacement at one year post-operatively. In
the series as a whole, quantitative-CT evaluation revealed similar densities
between affected and normal bone. Heterotopic ossification was observed
in four hips, without compromise of the clinical outcome. In this limited series AFG/BMP-7 combination proved a safe and
effective method for the treatment of femoral head osteonecrosis,
leading to early consolidation of the AFG and preventing collapse
in five of seven hips, while the operative time and post-operative
rehabilitation period were much shorter compared with free vascularised fibular
grafts. Cite this article:
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.
Louis Pasteur once said that: “Fortune favours
the prepared mind.” As one of the great scientists who contributed
to the fight against infection, he emphasised the importance of
being prepared at all times to recognise infection and deal with
it. Despite the many scientific discoveries and technological advances,
such as the advent of antibiotics and the use of sterile techniques,
infection continues to be a problem that haunts orthopaedic surgeons
and inflicts suffering on patients. The medical community has implemented many practices with the
intention of preventing infection and treating it effectively when
it occurs. Although high-level evidence may support some of these
practices, many are based on little to no scientific foundation.
Thus, around the world, there is great variation in practices for
the prevention and management of periprosthetic joint infection. This paper summaries the instigation, conduct and findings of
a recent International Consensus Meeting on Surgical Site and Periprosthetic
Joint Infection. Cite this article:
The increasing need for total hip replacement
(THR) in an ageing population will inevitably generate a larger number
of revision procedures. The difficulties encountered in dealing
with the bone deficient acetabulum are amongst the greatest challenges
in hip surgery. The failed acetabular component requires reconstruction
to restore the hip centre and improve joint biomechanics. Impaction
bone grafting is successful in achieving acetabular reconstruction
using both cemented and cementless techniques. Bone graft incorporation
restores bone stock whilst providing good component stability. We
provide a summary of the evidence and current literature regarding impaction
bone grafting using both cemented and cementless techniques in revision
THR. Cite this article:
We investigated the detailed anatomy of the gluteus
maximus, gluteus medius and gluteus minimus and their neurovascular
supply in 22 hips in 11 embalmed adult Caucasian human cadavers.
This led to the development of a surgical technique for an extended
posterior approach to the hip and pelvis that exposes the supra-acetabular
ilium and preserves the glutei during revision hip surgery. Proximal
to distal mobilisation of the gluteus medius from the posterior
gluteal line permits exposure and mobilisation of the superior gluteal
neurovascular bundle between the sciatic notch and the entrance
to the gluteus medius, enabling a wider exposure of the supra-acetabular
ilium. This technique was subsequently used in nine patients undergoing
revision total hip replacement involving the reconstruction of nine
Paprosky 3B acetabular defects, five of which had pelvic discontinuity.
Intra-operative electromyography showed that the innervation of
the gluteal muscles was not affected by surgery. Clinical follow-up
demonstrated good hip abduction function in all patients. These
results were compared with those of a matched cohort treated through
a Kocher–Langenbeck approach. Our modified approach maximises the
exposure of the ilium above the sciatic notch while protecting the
gluteal muscles and their neurovascular bundle. Cite this article: Bone Joint J 2014;96-B:48–53.