The aims of the study were to report for a cohort aged younger than 40 years: 1) indications for HRA; 2) patient-reported outcomes in terms of the modified Harris Hip Score (HHS); 3) dislocation rate; and 4) revision rate. This retrospective analysis identified 267 hips from 224 patients who underwent an hip resurfacing arthroplasty (HRA) from a single fellowship-trained surgeon using the direct lateral approach between 2007 and 2019. Inclusion criteria was minimum two-year follow-up, and age younger than 40 years. Patients were followed using a prospectively maintained institutional database.Aims
Methods
The aim of this study was to evaluate blood metal ion levels, leucocyte profiles, and serum cytokines in patients with a total hip arthroplasty (THA) involving modular dual-mobility components. A total of 39 patients were recruited, with clinical follow-up of up to two years. Outcome was assessed using the Harris Hip Score (HHS, the 12-Item Short-Form Health Survey (SF-12), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and a visual analogue scale (VAS) for pain. Blood concentrations of cobalt (Co), chromium (Cr), and serum cytokines were measured. Subpopulations of leucocytes were analyzed by flow cytometry.Aims
Patients and Methods
This study aimed to characterise and qualitatively grade the severity of the corrosion particles released into the hip joint following taper corrosion. The 26 cases examined were CoC/ABG Modular (n = 13) and ASR/SROM (n = 13). Blood serum metal ion levels were collected before and after revision surgery. The haematoxylin and eosin tissue sections were graded on the presence of fibrin exudates, necrosis, inflammatory cells and corrosion products. The corrosion products were identified based on visible observation and graded on abundance. Two independent observers blinded to the clinical patient findings scored all cases. Elemental analysis was performed on corrosion products within tissue sections. X-Ray diffraction was used to identify crystalline structures present in taper debris.Objectives
Methods
The peri-prosthetic
We undertook a retrospective cohort study to
determine clinical outcomes following the revision of metal-on-metal (MoM)
hip replacements for adverse reaction to metal debris (ARMD), and
to identify predictors of time to revision and outcomes following
revision. Between 1998 and 2012 a total of 64 MoM hips (mean age
at revision of 57.8 years; 46 (72%) female; 46 (72%) hip resurfacings
and 18 (28%) total hip replacements) were revised for ARMD at one specialist
centre. At a mean follow-up of 4.5 years (1.0 to 14.6) from revision
for ARMD there were 13 hips (20.3%) with post-operative complications
and eight (12.5%) requiring re-revision. The Kaplan–Meier five-year survival rate for ARMD revision was
87.9% (95% confidence interval 78.9 to 98.0; 19 hips at risk). Excluding
re-revisions, the median absolute Oxford hip score (OHS) following
ARMD revision using the percentage method (0% best outcome and 100%
worst outcome) was 18.8% (interquartile range (IQR) 7.8% to 48.3%),
which is equivalent to 39/48 (IQR 24.8/48 to 44.3/48) when using
the modified OHS. Histopathological response did not affect time
to revision for ARMD (p = 0.334) or the subsequent risk of re-revision
(p = 0.879). Similarly, the presence or absence of a contralateral
MoM hip bearing did not affect time to revision for ARMD (p = 0.066)
or the subsequent risk of re-revision (p = 0.178). Patients revised to MoM bearings had higher rates of re-revision
(five of 16 MoM hips re-revised; p = 0.046), but those not requiring
re-revision had good functional results (median absolute OHS 14.6%
or 41.0/48). Short-term morbidity following revision for ARMD was
comparable with previous reports. Caution should be exercised when choosing
bearing surfaces for ARMD revisions. Cite this article:
Abnormal wear of cobalt-containing metal-on-metal
joints is associated with inflammatory pseudotumours. Cobalt ions
activate human toll-like receptor 4 (TLR4), which normally responds
to bacterial lipopolysaccharide (LPS) in sepsis. Activation of TLR4
by LPS increases the expression of chemokines IL-8 and CXCL10, which
recruit leukocytes and activated T-cells, respectively. This study
was designed to determine whether cobalt induces a similar inflammatory
response to LPS by promoting the expression of IL-8 and CXCL10.
A human monocytic cell line, derived from acute monocytic leukaemia,
was treated with cobalt ions and expression of IL-8 and CXCL10 measured at
mRNA and protein levels. Cobalt-treated macrophages showed a 60-fold
increase in IL-8 mRNA, and an eightfold increase in production of
the mature chemokine (both p <
0.001); expression of the CXCL10
gene and protein was also significantly increased by cobalt (both
p <
0.001). Experiments were also performed in the presence of
CLI-095, a TLR4-specific antagonist which abrogated the cobalt-mediated
increase in IL-8 and CXCL10 expression. These findings suggest that cobalt ions induce inflammation similar
to that observed during sepsis by the simultaneous activation of
two TLR4-mediated signalling pathways. These pathways result in
increased production of IL-8 and CXCL10, and may be implicated in
pseudotumour formation following metal-on-metal replacement. Cite this article:
Our understanding of the origin of hip pain in
degenerative disorders of the hip, including primary osteoarthritis, avascular
necrosis and femoroacetabular impingement (FAI), is limited. We
undertook a histological investigation of the nociceptive innervation
of the acetabular labrum, ligamentum teres and capsule of the hip,
in order to prove pain- and proprioceptive-associated marker expression.
These structures were isolated from 57 patients who had undergone
elective hip surgery (44 labral samples, 33 ligamentum teres specimens,
34 capsular samples; in 19 patients all three structures were harvested).
A total of
15 000 histological sections were prepared that were investigated
immunohistochemically for the presence of protein S-100, 68 kDa
neurofilament, neuropeptide Y, nociceptin and substance P. The tissues
were evaluated in six representative areas. Within the labrum, pain-associated free nerve ending expression
was located predominantly at its base, decreasing in the periphery.
In contrast, the distribution within the ligamentum teres showed
a high local concentration in the centre. The hip capsule had an
almost homogeneous marker expression in all investigated areas. This study showed characteristic distribution profiles of nociceptive
and pain-related nerve fibres, which may help in understanding the
origin of hip pain. Cite this article:
Femoroacetabular impingement (FAI) is commonly
associated with early hip arthritis. We reviewed our series of 1300
hip resurfacing procedures. More than 90% of our male patients,
with an average age of 53 years, had cam impingement lesions. In
this condition, there are anterior femoral neck osteophytes, and
a retroverted femoral head on a normally anteverted neck. It is
postulated that FAI results in collision of the anterior neck of
the femur against the rim of the acetabulum, causing damage to the
acetabular labrum and articular cartilage, resulting in osteoarthritis.
Early treatment of FAI involves arthroscopic or open removal of
bone from the anterior femoral neck, as well as repair or removal
of labral tears. However, once osteoarthritis has developed, hip
replacement or hip resurfacing is indicated. Hip resurfacing can
re-orient the head and re-shape the neck. This helps to restore
normal biomechanics to the hip, eliminate FAI, and improve range
of motion. Since many younger men with hip arthritis have FAI, and
are also considered the best candidates for hip resurfacing, it
is evident that resurfacing has a role in these patients.
We present the 10- to 17-year results of 112 computer-assisted design computer-assisted manufacture femoral components. The total hip replacements were performed between 1992 and 1998 in 111 patients, comprising 53 men and 58 women. Their mean age was 46.2 years (24.6 to 62.2) with a mean follow-up of 13 years (10 to 17). The mean Harris Hip Score improved from 42.4 (7 to 99) to 90.3 (38 to 100), the mean Oxford Hip Score from 43.1 (12 to 59) to 18.2 (12 to 51) and the mean Western Ontario MacMasters University Osteoarthritis Index score from 57.0 (7 to 96) to 11.9 (0 to 85). There was one revision due to failure of the acetabular component but no failures of the femoral component. There were no revisions for aseptic loosening. The worst-case survival in this cohort of custom femoral components at 13.2 years follow-up was 98.2% (95% confidence interval 95 to 99). Overall survival of this series of total hip replacements was 97.3% (95% confidence interval 95 to 99). These results are comparable with the best medium- to long-term results for femoral components used in primary total hip replacement with any means of fixation.
We carried out metal artefact-reduction MRI, three-dimensional CT measurement of the position of the component and inductively-coupled plasma mass spectrometry analysis of cobalt and chromium levels in whole blood on 26 patients with unexplained pain following metal-on-metal resurfacing arthroplasty. MRI showed periprosthetic lesions around 16 hips, with 14 collections of fluid and two soft-tissue masses. The lesions were seen in both men and women and in symptomatic and asymptomatic hips. Using three-dimensional CT, the median inclination of the acetabular component was found to be 55° and its positioning was outside the Lewinnek safe zone in 13 of 16 cases. Using inductively-coupled plasma mass spectrometry, the levels of blood metal ions tended to be higher in painful compared with well-functioning metal-on-metal hips. These three clinically useful investigations can help to determine the cause of failure of the implant, predict the need for future revision and aid the choice of revision prostheses.
When using a staged approach to eradicate chronic infection after total hip replacement, systemic delivery of antibiotics after the first stage is often employed for an extended period of typically six weeks together with the use of an in situ antibiotic-eluting polymethylmethacrylate interval spacer. We report our multi-surgeon experience of 43 consecutive patients (44 hips) who received systemic vancomycin for two weeks in combination with a vancomycin- and gentamicin-eluting spacer system in the course of a two-stage revision procedure for deep infection with a median follow-up of 49 months (25 to 83). The antibiotic-eluting articulating spacers fractured in six hips (13.9%) and dislocated in five patients (11.6%). Successful elimination of the infecting organisms occurred in 38 (92.7%) of 41 hips with three patients developing superinfection with a new organism. We conclude that prolonged systemic antibiotic therapy may not be essential in the two-stage treatment of a total hip replacement for Gram-positive infection, provided that a high concentration of antibiotics is delivered locally using an antibiotic-eluting system.
We report the clinical and radiological outcome at ten years of 104 primary total hip replacements (100 patients) using the Metasul metal-on-metal bearing. Of these, 52 had a cemented Stuehmer-Weber polyethylene acetabular component with a Metasul bearing and 52 had an uncemented Allofit acetabular component with a Metasul liner. A total of 15 patients (16 hips) died before their follow-up at ten years and three were lost to follow-up. The study group therefore comprised 82 patients (85 hips). The mean Oxford score at ten years was 20.7 (12 to 42). Six of 85 hips required revision surgery. One was performed because of infection, one for aseptic loosening of the acetabular component and four because of unexplained pain. Histological examination showed an aseptic lymphocytic vasculitis associated lesion-type
We have compared four computer-assisted methods to measure penetration of the femoral head into the acetabular component in total hip replacement. These were the Martell Hip Analysis suite 7.14, Rogan HyperOrtho, Rogan View Pro-X and Roman v1.70. The images used for the investigation comprised 24 anteroposterior digital radiographs and 24 conventional acetate radiographs which were scanned to provide digital images. These radiographs were acquired from 24 patients with an uncemented total hip replacement with a follow-up of approximately eight years (mean 8.1; 6.3 to 9.1). Each image was measured twice by two blinded observers. The mean annual rates of penetration of the femoral head measured in the eight-year single image analysis were: Martell, 0.24 (SD 0.19); HyperOrtho, 0.12 (SD 0.08); View Pro-X, 0.12 (SD 0.06); Roman, 0.12 (SD 0.07). In paired analysis of the six-month and eight-year radiographs: Martell, 0.35 (SD 0.22); HyperOrtho, 0.15 (SD 0.13); View Pro-X, 0.11 (SD 0.06); Roman, 0.11 (SD 0.07). The intra- and inter-observer variability for the paired analysis was best for View Pro-X and Roman software, with intraclass correlations of 0.97, 0.87 and 0.96, 0.87, respectively, and worst for HyperOrtho and Martell, with intraclass correlations of 0.46, 0.13 and 0.33, 0.39, respectively. The Roman method proved the most precise and the most easy to use in clinical practice and the software is available free of charge. The Martell method showed the lowest precision, indicating a problem with its edge detection algorithm on digital images.
Modern metal-on-metal bearings produce less wear debris and osteolysis, but have the potential adverse effect of release of ions. Improved ceramic-on-ceramic bearings have the lowest wear of all, but the corrosion process has not been analysed. Our aim was to measure the serum ion release (ng/ml) in 23 patients having stable hip prostheses with a ceramic-on-ceramic coupling (group A) and to compare it with the release in 42 patients with a metal-on-metal bearing (group B) in the medium term. Reference values were obtained from a population of 47 healthy subjects (group C). The concentrations of chromium, cobalt, aluminium and titanium were measured. There was a significant increase of cobalt, chromium and aluminium levels (p <
0.05) in group B compared with groups A and C. Group A did not differ significantly from the control group. Despite the apparent advantage of a metal-on-metal coupling, especially in younger patients with a long life expectancy, a major concern arises regarding the extent and duration of ion exposure. For this reason, the low corrosion level in a ceramic-on-ceramic coupling could be advantageous.