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
There are limited published data detailing the volumetric material loss from tapers of conventional metal-on-polyethylene (MoP) total hip arthroplasties (THAs). Our aim was to address this by comparing the taper wear rates measured in an explanted cohort of the widely used Exeter THA with those measured in a group of metal-on-metal (MoM) THAs. We examined an existing retrieval database to identify all Exeter V40 and Universal MoP THAs. Volumetric wear analysis of the taper surfaces was conducted using previously validated methodology. These values were compared with those obtained from a series of MoM THAs using non-parametric statistical methodology. A number of patient and device variables were accounted for using multiple regression modelling.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
The goals of this study were to define the risk factors, nature,
chronology, and treatment strategies adopted for periprosthetic
femoral fractures in 32 644 primary total hip arthroplasties (THAs). There were 564 intra-operative fractures (1.7%); 529 during uncemented
stem placement (3.0%) and 35 during cemented stem placement (0.23%).
Intra-operative fractures were more common in females and patients
over 65 years (p <
0.001). The majority occurred during placement
of the femoral component (60%), and involved the calcar (69%). There
were 557 post-operative fractures (20-year probability: 3.5%; 95%
confidence interval (CI) 3.2 to 3.9); 335 fractures after placement
of an uncemented stem (20-year probability: 7.7%; 95% CI 6.2 to
9.1) and 222 after placement of a cemented stem (20-year probability:
2.1%; 95% CI 1.8 to 2.5). The probability of a post-operative fracture
within 30 days after an uncemented stem was ten times higher than
a cemented stem. The most common post-operative fracture type was
a Vancouver AG (32%; n = 135), with 67% occurring after
a fall. In all, 36% (n = 152) were treated with revision arthroplasty. Aim and Methods
Results
The aim of this randomised controlled study was
to compare functional and radiological outcomes between modern cemented
and uncemented hydroxyapatite coated stems after one year in patients
treated surgically for a fracture of the femoral neck. A total of
141 patients aged >
65 years were included. Patients were randomised
to be treated with a cemented Exeter stem or an uncemented Bimetric
stem. The patients were reviewed at four and 12 months. The cemented group performed better than the uncemented group
for the Harris hip score (78 In conclusion, our data do not support the use of an uncemented
hydroxyapatite coated stem for the treatment of displaced fractures
of the femoral neck in the elderly. Cite this article:
Revision knee arthroplasty presents a number
of challenges, not least of which is obtaining solid primary fixation
of implants into host bone. Three anatomical zones exist within
both femur and tibia which can be used to support revision implants.
These consist of the joint surface or epiphysis, the metaphysis
and the diaphysis. The methods by which fixation in each zone can
be obtained are discussed. The authors suggest that solid fixation
should be obtained in at least two of the three zones and emphasise
the importance of pre-operative planning and implant selection. Cite this article:
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
National Institute of Clinical Excellence guidelines
state that cemented stems with an Orthopaedic Data Evaluation Panel
(ODEP) rating of >
3B should be used for hemiarthroplasty when treating
an intracapsular fracture of the femoral neck. These recommendations
are based on studies in which most, if not all stems, did not hold
such a rating. This case-control study compared the outcome of hemiarthroplasty
using a cemented (Exeter) or uncemented (Corail) femoral stem. These
are the two prostheses most commonly used in hip arthroplasty in
the UK. Data were obtained from two centres; most patients had undergone
hemiarthroplasty using a cemented Exeter stem (n = 292/412). Patients
were matched for all factors that have been shown to influence mortality
after an intracapsular fracture of the neck of the femur. Outcome
measures included: complications, re-operations and mortality rates
at two, seven, 30 and 365 days post-operatively. Comparable outcomes
for the two stems were seen. There were more intra-operative complications in the uncemented
group (13% This study therefore supports the use of both cemented and uncemented
stems of proven design, with an ODEP rating of 10A, in patients
with an intracapsular fracture of the neck of the femur. Cite this article:
Periprosthetic femoral fractures (PFF) following total hip arthroplasty
(THA) are devastating complications that are associated with functional
limitations and increased overall mortality. Although cementless
implants have been associated with an increased risk of PFF, the
precise contribution of implant geometry and design on the risk
of both intra-operative and post-operative PFF remains poorly investigated.
A systematic review was performed to aggregate all of the PFF literature
with specific attention to the femoral implant used. A systematic search strategy of several journal databases and
recent proceedings from the American Academy of Orthopaedic Surgeons
was performed. Clinical articles were included for analysis if sufficient
implant description was provided. All articles were reviewed by
two reviewers. A review of fundamental investigations of implant
load-to-failure was performed, with the intent of identifying similar
conclusions from the clinical and fundamental literature.Aims
Patients and Methods
A total of 31 patients, (20 women, 11 men; mean
age 62.5 years old; 23 to 81), who underwent conversion of a Girdlestone
resection-arthroplasty (RA) to a total hip replacement (THR) were
compared with 93 patients, (60 women, 33 men; mean age 63.4 years
old; 20 to 89), who had revision THR surgery for aseptic loosening
in a retrospective matched case-control study. Age, gender and the
extent of the pre-operative bone defect were similar in all patients.
Mean follow-up was 9.3 years (5 to 18). Pre-operative function and range of movement were better in the
control group (p = 0.01 and 0.003, respectively) and pre-operative
leg length discrepancy (LLD) was greater in the RA group (p <
0.001). The post-operative clinical outcome was similar in both
groups except for mean post-operative LLD, which was greater in
the study group (p = 0.003). There was a significant interaction
effect for LLD in the study group (p <
0.001). A two-way analysis
of variance showed that clinical outcome depended on patient age
(patients older than 70 years old had worse pre-operative pain,
p = 0.017) or bone defect (patients with a large acetabular bone
defect had higher LLD, p = 0.006, worse post-operative function
p = 0.009 and range of movement, p = 0.005), irrespective of the
group. Despite major acetabular and femoral bone defects requiring complex
surgical reconstruction techniques, THR after RA shows a clinical
outcome similar to those obtained in aseptic revision surgery for
hips with similar sized bone defects. Cite this article:
The April 2012 Hip &
Pelvis Roundup360 looks at osteoporotic hip fractures, retrotrochanteric pain, fibrin adhesive and reattachment of articular cartilage, autologous bone marrow mononuclear cells and avascular necrosis, bearing surfaces, stability after THR, digital templating, pelvic tilt after THR, custom-made sockets for DDH, and dogs and THR
Radiological changes and differences between cemented and uncemented components of Grammont reverse shoulder arthroplasties (DePuy) were analysed at a mean follow-up of 9.6 years (8 to 12). Of 122 reverse shoulder arthroplasties implanted in five shoulder centres between 1993 and 2000, a total of 68 (65 patients) were available for study. The indications for reversed shoulder arthroplasty were cuff tear arthropathy in 48 shoulders, revision of shoulder prostheses of various types in 11 and massive cuff tear in nine. The development of scapular notching, bony scapular spur formation, heterotopic ossification, glenoid and humeral radiolucencies, stem subsidence, radiological signs of stress shielding and resorption of the tuberosities were assessed on standardised true anteroposterior and axillary radiographs. A scapular notch was observed in 60 shoulders (88%) and was associated with the superolateral approach (p = 0.009). Glenoid radiolucency was present in 11 (16%), bony scapular spur and/or ossifications in 51 (75%), and subsidence of the stem and humeral radiolucency in more than three zones were present in three (8.8%) and in four (11.8%) of 34 cemented components, respectively, and in one (2.9%) and two (5.9%) of 34 uncemented components, respectively. Radiological signs of stress shielding were significantly more frequent with uncemented components (p <
0.001), as was resorption of the greater (p <
0.001) and lesser tuberosities (p = 0.009).
Loss of bone stock is a major problem in revision surgery of the hip. Impaction bone grafting of the femur is frequently used when dealing with deficient bone stock. In this retrospective study a consecutive series of 68 patients (69 hips) who had revision of a hip replacement with femoral impaction grafting were reviewed. Irradiated bone allograft was used in all hips. Radiological measurement of subsidence of the stem, incorporation of the graft and remodelling was carried out and showed incorporation of the graft in 26 of 69 hips (38%). However, there was no evidence of trabecular remodelling. Moderate subsidence of 5 mm to 10 mm occurred in ten hips (14.5%), and massive subsidence of >
10 mm in five (7.2%). The results of this study are less favourable than those of others describing studies of revision of the femoral stem using impaction bone grafting. The absence of the characteristic changes of graft remodelling noted in other series raises the question as to whether irradiated bone graft may be a significant factor influencing the post-operative outcome.
Orthopaedic surgeons use stems in revision knee surgery to obtain
stability when metaphyseal bone is missing. No consensus exists
regarding stem size or method of fixation. This A custom test rig using differential variable reluctance transducers
(DVRTs) was developed to record all translational and rotational
motions at the bone–implant interface. Composite femurs were used.
These were secured to permit variation in flexion angle from 0°
to 90°. Cyclic loads were applied through a tibial component based
on three peaks corresponding to 0°, 10° and 20° flexion from a normal
walking cycle. Three different femoral components were investigated
in this study for cementless and cemented interface conditions.Objectives
Methods
This was a safety study where the hypothesis was that the newer-design CPCS femoral stem would demonstrate similar early clinical results and micromovement to the well-established Exeter stem. Both are collarless, tapered, polished cemented stems, the only difference being a slight lateral to medial taper with the CPCS stem. A total of 34 patients were enrolled in a single-blinded randomised controlled trial in which 17 patients received a dedicated radiostereometric CPCS stem and 17 a radiostereometric Exeter stem. No difference was found in any of the outcome measures pre-operatively or post-operatively between groups. At two years, the mean subsidence for the CPCS stem was nearly half that seen for the Exeter stem (0.77 mm (−0.943 to 1.77) and 1.25 mm (0.719 to 1.625), respectively; p = 0.032). In contrast, the mean internal rotation of the CPCS stem was approximately twice that of the Exeter (1.61° (−1.07° to 4.33°) and 0.59° (0.97° to 1.64°), respectively; p = 0.048). Other migration patterns were not significantly different between the stems. The subtle differences in designs may explain the different patterns of migration. Comparable migration with the Exeter stem suggests that the CPCS design will perform well in the long term.
We reviewed the results at nine to 13 years of 125 total hip replacements in 113 patients using the monoblock uncemented Morscher press-fit acetabular component. The mean age at the time of operation was 56.9 years (36 to 74). The mean clinical follow-up was 11 years (9.7 to 13.5) and the mean radiological follow-up was 9.4 years (7.7 to 13.1). Three hips were revised, one immediately for instability, one for excessive wear and one for deep infection. No revisions were required for aseptic loosening. A total of eight hips (7.0%) had osteolytic lesions greater than 1 cm, in four around the acetabular component (3.5%). One required bone grafting behind a well-fixed implant. The mean wear rate was 0.11 mm/year (0.06 to 0.78) and was significantly higher in components with a steeper abduction angle. Kaplan-Meier survival curves at 13 years showed survival of 96.8% (95% confidence interval 90.2 to 99.0) for revision for any cause and of 95.7% (95% confidence interval 88.6 to 98.4) for any acetabular re-operation.
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.