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:
It is becoming increasingly common for a patient
to have ipsilateral hip and knee replacements. The inter-prosthetic (IP)
distance, the distance between the tips of hip and knee prostheses,
has been thought to be associated with an increased risk of IP fracture.
Small gap distances are generally assumed to act as stress risers,
although there is no real biomechanical evidence to support this. The purpose of this study was to evaluate the influence of IP
distance, cortical thickness and bone mineral density on the likelihood
of an IP femoral fracture. A total of 18 human femur specimens were randomised into three
groups by bone density and cortical thickness. For each group, a
defined IP distance of 35 mm, 80 mm or 160 mm was created by choosing
the appropriate lengths of component. The maximum fracture strength
was determined using a four-point bending test. The fracture force of all three groups was similar (p = 0.498).
There was a highly significant correlation between the cortical
area and the fracture strength (r = 0.804, p <
0.001), whereas
bone density showed no influence. This study suggests that the IP distance has little influence
on fracture strength in IP femoral fractures: the thickness of the
cortex seems to be the decisive factor. Cite this article:
Pre-operative planning for total hip replacement
(THR) is challenging in hips with severe acetabular deformities, including
those with a hypoplastic acetabulum or severe defects and in the
presence of arthrodesis or ankylosis. We evaluated whether a Rapid
Prototype (RP) model, which is a life-sized reproduction based on
three-dimensional CT scans, can determine the feasibility of THR
and provide information about the size and position of the acetabular component
in severe acetabular deformities. THR was planned using an RP model
in 21 complex hips in five men (five hips) and 16 women (16 hips)
with a mean age of 47.7 years (24 to 70) at operation. An acetabular
component was implanted successfully and THR completed in all hips.
The acetabular component used was within 2 mm of the predicted size
in 17 hips (80.9%). All of the acetabular components and femoral
stems had radiological evidence of bone ingrowth and stability at
the final follow-up, without any detectable wear or peri-prosthetic
osteolysis. The RP model allowed a simulated procedure pre-operatively
and was helpful in determining the feasibility of THR pre-operatively,
and to decide on implant type, size and position in complex THRs. Cite this article:
Giant cell tumour is the most common aggressive
benign tumour of the musculoskeletal system and has a high rate of
local recurrence. When it occurs in proximity to the hip, reconstruction
of the joint is a challenge. Options for reconstruction after wide
resection include the use of a megaprosthesis or an allograft-prosthesis
composite. We performed a clinical and radiological study to evaluate
the functional results of a proximal femoral allograft-prosthesis
composite in the treatment of proximal femoral giant cell tumour
after wide resection. This was an observational study, between 2006
and 2012, of 18 patients with a mean age of 32 years (28 to 42)
and a mean follow-up of 54 months (18 to 79). We achieved excellent
outcomes using Harris Hip Score in 13 patients and a good outcome
in five. All allografts united. There were no complications such
as infection, failure, fracture or resorption of the graft, or recurrent
tumour. Resection and reconstruction of giant cell tumours with
proximal femoral allograft–prosthesis composite is a better option
than using a prosthesis considering preservation of bone stock and excellent
restoration of function. A good result requires demanding bone banking techniques, effective
measures to prevent infection and stability at the allograft-host
junction. Cite this article:
The October 2015 Hip &
Pelvis Roundup360 looks at: Smoking and complications in arthroplasty; Smoking cessation beneficial in arthroplasty; Intermediate care and arthroplasty; Do we still need cell salvage?; Femoroacetabular impingement in the Japanese population; Trunnionosis or taperosis and geometry; Decontamination for staphylococcus aureus works!; Policeman or opportunity? Quality improvement with registries; Death rates higher in readmission to other hospitals
We report the five-year outcome of a randomised
controlled trial which used radiostereometric analysis (RSA) to assess
the influence of surface oxidised zirconium (OxZr, Oxinium) on polyethylene
wear A total of 120 patients, 85 women and 35 men with a mean age
of 70 years (59 to 80) who were scheduled for primary cemented total
hip arthroplasty were randomly allocated to four study groups. Patients
were blinded to their group assignment and received either a conventional
polyethylene (CPE) or a highly cross-linked (HXL) acetabular component
of identical design. On the femoral side patients received a 28
mm head made of either cobalt-chromium (CoCr) or OxZr. The proximal head penetration (wear) was measured with repeated
RSA examinations over five years. Clinical outcome was measured
using the Harris hip score. There was no difference in polyethylene wear between the two
head materials when used with either of the two types of acetabular
component (p = 0.3 to 0.6). When comparing the two types of polyethylene
there was a significant difference in favour of HXLPE, regardless
of the head material used (p <
0.001). In conclusion, we found no advantage of OxZr over CoCr in terms
of polyethylene wear after five years of follow-up. Our findings
do not support laboratory results which have shown a reduced rate
of wear with OxZr. They do however add to the evidence on the better
resistance to wear of HXLPE over CPE. 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:
We compared the incidence of pseudotumours after
large head metal-on-metal (MoM) total hip arthroplasty (THA) with
that after conventional metal-on-polyethylene (MoP) THA and assessed
the predisposing factors to pseudotumour formation. From a previous randomised controlled trial which compared large
head (38 mm to 60 mm) cementless MoM THA with conventional head
(28 mm) cementless MoP THA, 93 patients (96 THAs: 41 MoM (21 males,
20 females, mean age of 64 years, standard deviation ( The incidence of pseudotumours, measured using a standardised
CT protocol was 22 (53.7%) after MoM THA and 12 (21.8%) after MoP
THA. Women with a MoM THA were more likely to develop a pseudotumour
than those with a MoP THA (15 Contrary to popular belief, pseudotumours occur frequently around
MoP THAs. Women with a MoM THA and an elevated cobalt level are
at greatest risk. In this study, pseudotumours had no effect on
the functional outcome after either large head MoM or conventional
MoP THA. Cite this article:
A number of studies have reported satisfactory
results from the isolated revision of an acetabular component. However,
many of these studies reported only the short- to intermediate-term
results of heterogeneous bearing surfaces in a mixed age group. We present our experience of using a ceramic-on-ceramic (CoC)
bearing for isolated revision of an uncemented acetabular component
in 166 patients (187 hips) who were under the age of 50 years at
the time of revision. There were 78 men and 88 women with a mean
age of 47.4 years (28 to 49). The most common reason for revision
was polyethylene wear and acetabular osteolysis in 123 hips (66%),
followed by aseptic loosening in 49 hips (26%). We report the clinical and radiological outcome, complication
rate, and survivorship of this group. The mean duration of follow-up
was 15.6 years (11 to 19). The mean pre-operative Harris hip score was 33 points (1 to 58),
and improved to a mean of 88 points (51 to 100) at follow-up. The
mean pre-operative total Western Ontario and McMaster Universities
Osteoarthritis Index score was 63.2 (43 to 91) and improved to 19.8
points (9 to 61) post-operatively. Overall, 153 of 166 patients
(92%) were satisfied with their outcome. Kaplan–Meier survivorship
analysis, with revision or radiological evidence of implant failure
(13 patients, 8%) as end-points, was 92% at 15 years (95% confidence
interval 0.89 to 0.97). Isolated revision of a cementless acetabular component using
a CoC bearing gives good results in patients under 50 years of age. Cite this article:
Adverse reaction to wear and corrosion debris
is a cause for concern in total hip arthroplasty (THA). Modular junctions
are a potential source of such wear products and are associated
with secondary pseudotumour formation. We present a consecutive series of 17 patients treated at our
unit for this complication following metal-on-highly cross-linked
polyethylene (MoP) THA. We emphasise the risk of misdiagnosis as
infection, and present the aggregate laboratory results and pathological
findings in this series. The clinical presentation was pain, swelling or instability.
Solid, cystic and mixed soft-tissue lesions were noted on imaging
and confirmed intra-operatively. Corrosion at the head–neck junction
was noted in all cases. No bacteria were isolated on multiple pre-
and intra-operative samples yet the mean erythrocyte sedimentation
rate was 49 (9 to 100) and C-reactive protein 32 (0.6 to 106) and
stromal polymorphonuclear cell counts were noted in nine cases. Adverse soft–tissue reactions can occur in MoP THA owing to corrosion
products released from the head–neck junction. The diagnosis should
be carefully considered when investigating pain after THA. This
may avoid the misdiagnosis of periprosthetic infection with an unidentified
organism and mitigate the unnecessary management of these cases
with complete single- or two-stage exchange. Cite this article:
There is a North Atlantic divide, with cementless
femoral stems being used more frequently in the USA and cemented
stems being used more frequently in many countries in Europe. This
is primarily because different cemented stems have been used on
different sides of the Atlantic and the results of the cemented
stems in the US have often been poor, whereas the results of the
stems used in Europe have been good. In the National registers in
Europe, cemented stems have tended to achieve better results than
cementless. Cite this article:
The peri-prosthetic tissue response to wear debris
is complex and influenced by various factors including the size, area
and number of particles. We hypothesised that the ‘biologically
active area’ of all metal wear particles may predict the type of
peri-prosthetic tissue response. Peri-prosthetic tissue was sampled from 21 patients undergoing
revision of a small diameter metal-on-metal (MoM) total hip arthroplasty
(THA) for aseptic loosening. An enzymatic protocol was used for
tissue digestion and scanning electron microscope was used to characterise
particles. Equivalent circle diameters and particle areas were calculated.
Histomorphometric analyses were performed on all tissue specimens.
Aspirates of synovial fluid were collected for analysis of the cytokine
profile analysis, and compared with a control group of patients
undergoing primary THA (n = 11) and revision of a failed ceramic-on-polyethylene
arthroplasty (n = 6). The overall distribution of the size and area of the particles
in both lymphocyte and
non-lymphocyte-dominated responses were similar; however, the subgroup
with lymphocyte-dominated peri-prosthetic tissue responses had a
significantly larger total number of particles. 14 cytokines (interleukin (IL)-1ß, IL-2, IL-4, IL-5, IL-6, IL-10,
IL-13, IL-17, interferon (IFN)-γ, and IFN-gamma-inducible protein
10), chemokines (macrophage inflammatory protein (MIP)-1α and MIP-1ß),
and growth factors (granulocyte macrophage colony stimulating factor
(GM-CSF) and platelet derived growth factor) were detected at significantly higher
levels in patients with metal wear debris compared with the control
group. Significantly higher levels for IL-1ß, IL-5, IL-10 and GM-CSF
were found in the subgroup of tissues from failed MoM THAs with
a lymphocyte-dominated peri-prosthetic response compared with those
without this response. These results suggest that the ‘biologically active area’ predicts
the type of
peri-prosthetic tissue response. The cytokines IL-1ß, IL-5, IL-10,
and GM-CSF are associated with lymphocyte-dominated tissue responses
from failed small-diameter MoM THA. Cite this article:
The aim of our study was to describe the characteristics,
treatment, and outcomes of patients with periprosthetic joint infection
(PJI) and normal inflammatory markers after total knee arthroplasty
(TKA) and total hip arthroplasty (THA). In total 538 TKAs and 414 THAs underwent surgical treatment for
PJI and met the inclusion criteria. Pre-operative erythrocyte sedimentation
rate (ESR) and C-reactive protein level (CRP) were reviewed to identify
the seronegative cohort. An age- and gender-matched cohort was identified
from the remaining patients for comparison. Overall, 4% of confirmed
infections were seronegative (21 TKA and 17 THA). Of those who underwent
pre-operative aspiration, cultures were positive in 76% of TKAs
(n = 13) and 64% of THAs (n = 7). Cell count and differential were
suggestive of infection in 85% of TKA (n = 11) and all THA aspirates
(n = 5). The most common organism was coagulase-negative Cite this article:
Between 1999 and 2001, 90 patients underwent
total hip replacement using the same uncemented acetabular and femoral
components with a 28 mm metallic femoral head but with prospective
randomisation of the acetabular liner to either Durasul highly cross-linked
polyethylene or nitrogen-sterilised Sulene polyethylene. We assessed
83 patients at a minimum follow-up of ten years. Linear penetration
of the femoral head was estimated at six weeks, six and 12 months
and annually thereafter, using the Dorr method, given the non-spherical
shape of the acetabular component. There was no loosening of any component; only one hip in the
Sulene group showed proximal femoral osteolysis. The mean penetration
of the femoral head at six weeks was 0.08 mm (0.02 to 0.15) for
the Durasul group and 0.16 mm (0.05 to 0.28) for the Sulene group
(p = 0.001). The mean yearly linear penetration was 64.8% lower
for the Durasul group at 0.05 mm/year ( Cite this article:
Ankle replacements have improved significantly since the first reported attempt at resurfacing of the talar dome in 1962. We are now at a stage where ankle replacement offers a viable option in the treatment of end-stage ankle arthritis. As the procedure becomes more successful, it is important to reflect and review the current surgical outcomes. This allows us to guide our patients in the treatment of end-stage ankle arthritis. What is the better surgical treatment – arthrodesis or replacement?
The October 2013 Hip &
Pelvis Roundup360 looks at: Young and impinging; Clothes, weather and femoral heads?; Go long, go cemented; Surgical repair of the abductors?; Aspirin for DVT prophylaxis?; Ceramic-on-polyethylene: a low-wear solution?; ALVAL and ASR™: the story continues….; Salvaging Legg-Calve-Perthes’ disease
Ceramic-on-metal (CoM) is a relatively new bearing
combination for total hip arthroplasty (THA) with few reported outcomes.
A total of 287 CoM THAs were carried out in 271 patients (mean age
55.6 years (20 to 77), 150 THAs in female patients, 137 in male)
under the care of a single surgeon between October 2007 and October
2009. With the issues surrounding metal-on-metal bearings the decision
was taken to review these patients between March and November 2011,
at a mean follow-up of 34 months (23 to 45) and to record pain,
outcome scores, radiological analysis and blood ion levels. The
mean Oxford Hip Score was 19.2 (12 to 53), 254 patients with 268
hips (95%) had mild/very mild/no pain, the mean angle of inclination
of the acetabular component was 44.8o (28o to
63o), 82 stems (29%) had evidence of radiolucent lines
of >
1 mm in at least one Gruen zone and the median levels of cobalt
and chromium ions in the blood were 0.83 μg/L (0.24 μg/L to 27.56 μg/L)
and 0.78 μg/L (0.21 μg/L to 8.84 μg/L), respectively. The five-year
survival rate is 96.9% (95% confidence interval 94.7% to 99%). Due to the presence of radiolucent lines and the higher than
expected levels of metal ions in the blood, we would not recommend
the use of CoM THA without further long-term follow-up. We plan
to monitor all these patients regularly. Cite this article:
Stems may improve fixation and stability of components
during revision total knee replacement. However, the choice between
cemented and cementless stems is not a clear one. Cemented stems
offer several advantages in terms of versatility, mechanical stability, surgical
technique and clinical outcome over their cementless counterpart. Cite this article:
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 polished Exeter stem. All patients were
followed prospectively. The mean age of the patients at revision
was 65 years (30 to 86). At final review in December 2013 a total
of 130 patients with 135 reconstructions (64.9%) were alive and
had a non re-revised femoral component after a mean follow-up of
10.6 years (4.7 to 20.9). One patient was lost to follow-up at six
years, and their data were included up to this point.
Re-operation for any reason was performed in 33 hips (15.9%), in
13 of which the femoral component was re-revised (6.3%). The mean
pre-operative Harris hip score was 52 (19 to 95) (n = 73) and improved
to 80 (22 to 100) (n = 161) by the last follow-up. Kaplan–Meier
survival with femoral re-revision for any reason as the endpoint
was 94.9% (95% confidence intervals (CI) 90.2 to 97.4) at ten years;
with femoral re-revision for aseptic loosening as the endpoint it was
99.4% (95% CI 95.7 to 99.9); with femoral re-operation for any reason
as the endpoint it was 84.5% (95% CI 78.3 to 89.1); and with subsidence ≥ 5
mm it was 87.3% (95% CI 80.5 to 91.8). Femoral revision with the
use of impaction allograft bone grafting and a cemented polished
stem results in a satisfying survival rate at a mean of ten years’ follow-up. Cite this article: