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:
Revision total hip arthroplasty (THA) is projected
to increase by 137% from the years 2005 to 2030. Reconstruction of
the femur with massive bone loss can be a formidable undertaking.
The goals of revision surgery are to create a stable construct,
preserve bone and soft tissues, augment deficient host bone, improve
function, provide a foundation for future surgery, and create a
biomechanically restored hip. Options for treatment of the compromised femur
include: resection arthroplasty, allograft prosthetic composite
(APC), proximal femoral replacement, cementless fixation with a
modular tapered fluted stem, and impaction grafting. The purpose
of this article is to review the treatment options along with their
associated outcomes in the more severe femoral defects (Paprosky types
IIIb and IV) in revision THA.
The goals of this study were to define the risk factors, characteristics,
and chronology of fractures in 5417 revision total hip arthroplasties
(THAs). From our hospital’s prospectively collected database we identified
all patients who had undergone a revision THA between 1969 and 2011
which involved the femoral stem. The patients’ medical records and
radiographs were examined and the relevant data extracted. Post-operative
periprosthetic fractures were classified using the Vancouver system.
A total of 5417 revision THAs were identified.Aims
Patients and Methods
Recurrent infection following two-stage revision total hip arthroplasty
(THA) for prosthetic joint infection (PJI) is a devastating complication.
The purpose of this study was to report the survival of repeat two-stage
revision hip arthroplasty, describe complications, and identify
risk factors for failure. We retrospectively identified 19 hips (19 patients) that had
undergone repeat two-stage revision THA for infection between 2000
to 2013. There were seven female patients (37%) and the mean age
was 60 years (30 to 85). Survival free from revision was assessed
via Kaplan–Meier analysis. The patients were classified according
to the Musculoskeletal Infection Society (MSIS) system, and risk
factors for failure were identified. Mean follow-up was four years
(2 to 11).Aims
Patients and Methods
Loss or absence of proximal femoral bone in revision total hip
arthroplasty (THA) remains a significant challenge. While the main
indication for the use of proximal femoral replacements (PFRs) is
in the treatment of malignant disease, they have a valuable role
in revision THA for loosening, fracture and infection in patients
with bone loss. Our aim was to determine the clinical outcomes,
implant survivorship, and complications of PFRs used in revision
THA for indications other than malignancy. A retrospective review of 44 patients who underwent revision
THA using a PFR between 2000 and 2013 was undertaken. Their mean
age was 79 years (53 to 97); 31 (70%) were women. The bone loss
was classified as Paprosky IIIB or IV in all patients. The mean
follow-up was six years (2 to 12), at which time 22 patients had
died and five were lost to follow-up.Aims
Patients and Methods
To evaluate the hypothesis that failed osteosynthesis of periprosthetic
Vancouver type B1 fractures can be treated successfully with stem
revision using a transfemoral approach and a cementless, modular,
tapered revision stem with reproducible rates of fracture healing,
stability of the revision stem, and clinically good results. A total of 14 patients (11 women, three men) with a mean age
of 72.4 years (65 to 90) undergoing revision hip arthroplasty after
failed osteosynthesis of periprosthetic fractures of Vancouver type
B1 were treated using a transfemoral approach to remove the well-fixed
stem before insertion of a modular, fluted titanium stem which obtained
distal fixation. These patients were clinically and radiologically
followed up for a mean 52.2 months (24 to 144).Aims
Patients and Methods
We are currently facing an epidemic of periprosthetic
fractures around the hip. They may occur either during surgery or
post-operatively. Although the acetabulum may be involved, the femur
is most commonly affected. We are being presented with new, difficult
fracture patterns around cemented and cementless implants, and we
face the challenge of an elderly population who may have grossly
deficient bone and may struggle to rehabilitate after such injuries.
The correct surgical management of these fractures is challenging.
This article will review the current choices of implants and techniques
available to deal with periprosthetic fractures of the femur. 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
Tribocorrosion at the head–neck taper interface
– so-called ‘taperosis’ – may be a source of metal ions and particulate
debris in metal-on-polyethylene total hip arthroplasty (THA). We examined the effect of femoral head length on fretting and
corrosion in retrieved head–neck tapers Head length was observed to affect fretting (p = 0.03), with
28 mm + 8 mm femoral heads showing greater total fretting scores
than all other head lengths. The central zone of the femoral head
bore taper was subject to increased fretting damage (p = 0.01),
regardless of head length or stem offset. High-offset femoral stems
were associated with greater total fretting of the bore taper (p
= 0.04). Increased fretting damage is seen with longer head lengths and
high-offset femoral stems, and occurs within a central concentric
zone of the femoral head bore taper. Further investigation is required
to determine the effect of increased head size, and variations in
head–neck taper design. 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:
A modular femoral head–neck junction has practical
advantages in total hip replacement. Taper fretting and corrosion
have so far been an infrequent cause of revision. The role of design
and manufacturing variables continues to be debated. Over the past
decade several changes in technology and clinical practice might
result in an increase in clinically significant taper fretting and
corrosion. Those factors include an increased usage of large diameter
(36 mm) heads, reduced femoral neck and taper dimensions, greater
variability in taper assembly with smaller incision surgery, and
higher taper stresses due to increased patient weight and/or physical
activity. Additional studies are needed to determine the role of
taper assembly compared with design, manufacturing and other implant
variables. Cite this article:
Dislocation remains among the most common complications
of, and reasons for, revision of both primary and revision total
hip replacements (THR). Hence, there is great interest in maximising
stability to prevent this complication. Head size has been recognised
to have a strong influence on the risk of dislocation post-operatively.
As femoral head size increases, stability is augmented, secondary
to an increase in impingement-free range of movement. Larger head
sizes also greatly increase the ‘jump distance’ required for the
head to dislocate in an appropriately positioned cup. Level-one
studies support the use of larger diameter heads as they decrease
the risk of dislocation following primary and revision THR. Highly cross-linked
polyethylene has allowed us to increase femoral head size, without
a marked increase in wear. However, the thin polyethylene liners
necessary to accommodate larger heads may increase the risk of liner
fracture and larger heads have also been implicated in causing soft-tissue
impingement resulting in groin pain. Larger diameter heads also
impart larger forces on the femoral trunnion, which may contribute
to corrosion, metal release, and adverse local tissue reactions.
Alternative large bearings including large ceramic heads and dual
mobility bearings may mitigate some of these risks, and several
of these devices have been used with clinical success. Cite this article:
Most hip fractures treated with modern internal
fixation techniques will heal. However, failures occasionally occur and
require revision procedures. Salvage strategies employed during
revision are based on whether the fixation failure occurs in the
femoral neck, or in the intertrochanteric region. Patient age and
remaining bone stock also influence decision making. For fractures
in young patients, efforts are generally focused on preserving the
native femoral head via osteotomies and repeat internal fixation.
For failures in older patients, some kind of hip replacement is
usually selected. Disuse osteopenia, deformity, bone loss, and stress-risers
from previous internal fixation devices all pose technical challenges
to successful reconstruction. Attention to detail is important in
order to minimise complications. In the majority of cases, good
outcomes have been reported for the various salvage strategies. Cite this article:
Two-stage exchange remains the gold standard
for treatment of peri-prosthetic joint infection after total hip replacement
(THR). In the first stage, all components and associated cement
if present are removed, an aggressive debridement is undertaken
including a complete synovectomy, and an antibiotic-loaded cement
spacer is put in place. Patients are then treated with six weeks
of parenteral antibiotics, followed by an ‘antibiotic free period’
to help ensure the infection has been eradicated. If the clinical
evaluation and serum inflammatory markers suggest the infection
has resolved, then the second stage can be completed, which involves
removal of the cement spacer, repeat debridement, and placement
of a new THR. Cite this article:
We report on 397 consecutive revision total hip
replacements in 371 patients with a mean clinical and radiological follow-up
of 12.9 years (10 to 17.7). The mean age at surgery was 69 years
(37 to 93). A total of 28 patients (8%) underwent further revision,
including 16 (4%) femoral components. In all 223 patients (56%,
233 hips) died without further revision and 20 patients (5%, 20
hips) were lost to follow-up. Of the remaining patients, 209 (221
hips) were available for clinical assessment and 194 (205 hips)
for radiological review at mean follow-up of 12.9 years (10 to 17.7). The mean Harris Hip Score improved from 58.7 (11 to 92) points
to 80.7 (21 to 100) (p <
0.001) and the mean Merle d’Aubigné and
Postel hip scores at final follow-up were 4.9 (2 to 6), 4.5 (2 to
6) and 4.3 (2 to 6), respectively for pain, mobility and function.
Radiographs showed no lucencies around 186 (90.7%) femoral stems
with stable bony ingrowth seen in 199 stems (97%). The survival
of the S-ROM femoral stem at 15 years with revision for any reason as
the endpoint was 90.5% (95% confidence interval (CI) 85.7 to 93.8)
and with revision for aseptic loosening as the endpoint 99.3% (95%
CI 97.2 to 99.8). We have shown excellent long-term survivorship and good clinical
outcome of a cementless hydroxyapatite proximally-coated modular
femoral stem in revision hip surgery. Cite this article:
The purpose of this paper is to discuss the risk
factors, prevention strategies, classification, and treatment of
intra-operative femur fractures sustained during primary and revision
total hip arthroplasty.
We present a series of 35 patients (19 men and
16 women) with a mean age of 64 years (36.7 to 75.9), who underwent
total hip replacement using the ESKA dual-modular short stem with
metal on-polyethylene bearing surfaces. This implant has a modular
neck section in addition to the modular head. Of these patients,
three presented with increasing post-operative pain due to pseudotumour
formation that resulted from corrosion at the modular neck-stem
junction. These patients underwent further surgery and aseptic lymphocytic
vaculitis associated lesions were demonstrated on histological analysis. Retrieval analysis of two modular necks showed corrosion at the
neck-stem taper. Blood cobalt and chromium levels were measured
at a mean of nine months (3 to 28) following surgery. These were
compared with the levels in seven control patients (three men and
four women) with a mean age of 53.4 years (32.1 to 64.1), who had
an identical prosthesis and articulation but with a prosthesis that
had no modularity at neck-stem junction. The mean blood levels of
cobalt in the study group were raised at 50.75 nmol/l (5 to 145)
compared with 5.6 nmol/l (2 to 13) in control patients. Corrosion at neck-stem tapers has been identified as an important
source of metal ion release and pseudotumour formation requiring
revision surgery. Finite element modelling of the dual modular stem
demonstrated high stresses at the modular stem-neck junction. Dual
modular cobalt-chrome hip prostheses should be used with caution
due to these concerns.
We investigated the changes seen on serial metal
artefact reduction magnetic resonance imaging scans (MARS-MRI) of
metal-on-metal total hip arthroplasties (MoM THAs). In total 155
THAs, in 35 male and 100 female patients (mean age 70.4 years, 42
to 91), underwent at least two MRI scans at a mean interval of 14.6
months (2.6 to 57.1), at a mean of 48.2 months (3.5 to 93.3) after
primary hip surgery. Scans were graded using a modification of the
Oxford classification. Progression of disease was defined as an
increase in grade or a minimum 10% increase in fluid lesion volume
at second scan. A total of 16 hips (30%) initially classified as
‘normal’ developed an abnormality on the second scan. Of those with
‘isolated trochanteric fluid’ 9 (47%) underwent disease progression,
as did 7 (58%) of ‘effusions’. A total of 54 (77%) of hips initially
classified as showing adverse reactions to metal debris (ARMD) progressed,
with higher rates of progression in higher grades. Disease progression
was associated with high blood cobalt levels or an irregular pseudocapsule
lining at the initial scan. There was no association with changes
in functional scores. Adverse reactions to metal debris in MoM THAs
may not be as benign as previous reports have suggested. Close radiological
follow-up is recommended, particularly in high-risk groups. Cite this article:
We compared a modular neck system with a non-modular system in a cementless anatomical total hip replacement (THR). Each group consisted of 74 hips with developmental hip dysplasia. Both groups had the same cementless acetabular component and the same articulation, which consisted of a conventional polyethylene liner and a 28 mm alumina head. The mean follow-up was 14.5 years (13 to 15), at which point there were significant differences in the mean total Harris hip score (modular/non-modular: 98.6 (64 to 100)/93.8 (68 to 100)), the mean range of abduction (32° (15° to 40°)/28 (0° to 40°)), use of a 10° elevated liner (31%/100%), the incidence of osteolysis (27%/79.7%) and the incidence of equal leg lengths (≥ 6 mm, 92%/61%). There was no disassociation or fracture of the modular neck. The modular system reduces the need for an elevated liner, thereby reducing the incidence of osteolysis. It gives a better range of movement and allows the surgeon to make an accurate adjustment of leg length.
Revision surgery of the hip was performed on 114 hips using an extensively porous-coated femoral component. Of these, 95 hips (94 patients) had a mean follow-up of 10.2 years (5 to 17). No cortical struts were used and the cortical index and the femoral cortical width were measured at different levels. There were two revisions for aseptic loosening. Survivorship at 12 years for all causes of failure was 96.9% (95% confidence interval 93.5 to 100) in the best-case scenario. Fibrous or unstable fixation was associated with major bone defects. The cortical index (p = 0.045) and the lateral cortical thickness (p = 0.008) decreased at the proximal level over time while the medial cortex increased (p = 0.001) at the proximal and distal levels. An increase in the proximal medial cortex was found in patients with an extended transtrochanteric osteotomy (p = 0.026) and in those with components shorter than 25 cm (p = 0.008). The use of the extensively porous-coated femoral component can provide a solution for difficult cases in revision surgery. Radiological bony ingrowth is common. Although without clinical relevance at the end of follow-up, the thickness of the medial femoral cortex often increased while that of the lateral cortex decreased. In cases in which a shorter component was used and in those undertaken using an extended trochanteric osteotomy, there was a greater increase in thickness of the femoral cortex over time.
The differential diagnosis of the painful total
hip arthroplasty (resurfacing or total hip) includes infection,
failure of fixation (loosening), tendinitis, bursitis, synovitis,
adverse local tissue reaction (ALTR) to cobalt-chromium alloys,
and non-hip issues, such as spinal disorders, hernia, gynecologic,
and other pelvic pain. Assuming that the hip is the source of pain,
the first level question is prosthetic or non-prosthetic pain generator?
The second level prosthetic question is septic or aseptic? The third
level question (aseptic hips) is well-fixed or loose? ALTR is best
diagnosed by cross-sectional imaging. Successful treatment is dependent
on correct identification and elimination of the pain generator.
Treatment recommendations for ALTR and taper corrosion are evolving.
Revision after failed femoral components may
be technically demanding due to loss of peri-prosthetic bone. This retrospective
study evaluated the long-term results of femoral revision using
the cementless Wagner Self-Locking stem. Between 1992 and 1998,
68 consecutive hips in 66 patients underwent femoral revision using
this implant. A total of 25 patients died from unrelated causes
without further revision; the remaining 41 hips in 41 patients (12 men
and 29 women) with a mean age of 61 years (29 to 80) were reviewed
at a mean follow-up of 13.9 years (10.4 to 15.8). A transfemoral
approach was used in 32 hips. A total of five stems required further
revision because of infection in two, progressive subsidence in
two and recurrent dislocation in one. Four hips had dislocated and
eight stems had subsided ≥ 10 mm. The mean Harris hip score improved
from 33 points pre-operatively to 75 points at final follow-up (p
<
0.001). In all, 33 stems (91.7%) showed radiological signs
of stable bone fixation. The cumulative survival rates at 15.8 years
with femoral revision for any reason and for stem failure as the
endpoints were 92.0% (95% confidence interval (CI) 86.0% to 98.4%)
and 96.6% (95% CI 92.2% to 100%), respectively. The survivorship
with revision and ≥ 10 mm migration of the stem as the endpoint
was 83.6% (95% CI 76.6% to 91.4%). This study shows quite good survival and moderate clinical outcome
when using a monoblock tapered titanium stem for supporting the
regeneration of bone in complex revision hip surgery.
We assessed the outcome of patients with Vancouver type B2 and B3 periprosthetic fractures treated with femoral revision using an uncemented extensively porous-coated implant. A retrospective clinical and radiographic assessment of 22 patients with a mean follow-up of 33.7 months was performed. The mean time from the index procedure to fracture was 10.8 years. There were 17 patients with a satisfactory result. Complications in four patients included subsidence in two, deep sepsis in one, and delayed union in one. Concomitant acetabular revision was required in 19 patients. Uncemented extensively porous-coated femoral stems incorporate distally allowing stable fixation. We found good early survival rates and a low incidence of nonunion using this implant.