There is little evidence on the cost effectiveness
of different brands of hip prostheses. We compared lifetime cost effectiveness
of frequently used brands within types of prosthesis including cemented
(Exeter V40 Contemporary, Exeter V40 Duration and Exeter V40 Elite
Plus Ogee), cementless (Corail Pinnacle, Accolade Trident, and Taperloc Exceed)
and hybrid (Exeter V40 Trilogy, Exeter V40 Trident, and CPT Trilogy).
We used data from three linked English national databases to estimate
the lifetime risk of revision, quality-adjusted life years (QALYs)
and cost. For women with osteoarthritis aged 70 years, the Exeter V40 Elite
Plus Ogee had the lowest risk of revision (5.9% revision risk, 9.0
QALYs) and the CPT Trilogy had the highest QALYs (10.9% revision
risk, 9.3 QALYs). Compared with the Corail Pinnacle (9.3% revision
risk, 9.22 QALYs), the most commonly used brand, and assuming a
willingness-to-pay of £20 000 per QALY gain, the CPT Trilogy is
most cost effective, with an incremental net monetary benefit of £876.
Differences in cost effectiveness between the hybrid CPT Trilogy
and Exeter V40 Trident and the cementless Corail Pinnacle and Taperloc
Exceed were small, and a cautious interpretation is required, given
the limitations of the available information. However, it is unlikely that cemented brands are among the most
cost effective. Similar patterns of results were observed for men
and other ages. The gain in quality of life after total hip arthroplasty,
rather than the risk of revision, was the main driver of cost effectiveness. Cite this article:
This study reports the mid-term results of a large-bearing hybrid metal-on-metal total hip replacement in 199 hips (185 patients) with a mean follow-up of 62 months (32 to 83). Two patients died of unrelated causes and 13 were lost to follow-up. In all, 17 hips (8.5%) have undergone revision, and a further 14 are awaiting surgery. All revisions were symptomatic. Of the revision cases, 14 hips showed evidence of adverse reactions to metal debris. The patients revised or awaiting revision had significantly higher whole blood cobalt ion levels (p = 0.001), but no significant difference in acetabular component size or position compared with the unrevised patients. Wear analysis (n = 5) showed increased wear at the trunnion-head interface, normal levels of wear at the articulating surfaces and evidence of corrosion on the surface of the stem. The cumulative survival rate, with revision for any reason, was 92.4% (95% confidence interval 87.4 to 95.4) at five years. Including those awaiting surgery, the revision rate would be 15.1% with a cumulative survival at five years of 89.6% (95% confidence interval 83.9 to 93.4). This hybrid metal-on-metal total hip replacement series has shown an unacceptably high rate of failure, with evidence of high wear at the trunnion-head interface and passive corrosion of the stem surface. This raises concerns about the use of large heads on conventional 12/14 tapers.
This review examines the future of total hip arthroplasty, aiming to avoid past mistakes
We reviewed 142 consecutive primary total hip replacements implanted into 123 patients between 1988 and 1993 using the Exeter Universal femoral stem. A total of 74 patients (88 hips) had survived for ten years or more and were reviewed at a mean of 12.7 years (10 to 17). There was no loss to follow-up. The rate of revision of the femoral component for aseptic loosening and osteolysis was 1.1% (1 stem), that for revision for any cause was 2.2% (2 stems), and for re-operation for any cause was 21.6% (19 hips). Re-operation was because of failure of the acetabular component in all but two hips. All but one femoral component subsided within the cement mantle to a mean of 1.52 mm (0 to 8.3) at the final follow-up. One further stem had subsided excessively (8 mm) and had lucent lines at the cement-stem and cement-bone interfaces. This was classified as a radiological failure and is awaiting revision. One stem was revised for deep infection and one for excessive peri-articular osteolysis. Defects of the cement mantle (Barrack grade C and D) were found in 28% of stems (25 hips), associated with increased subsidence (p = 0.01), but were not associated with endosteal lysis or failure. Peri-articular osteolysis was significantly related to the degree of polyethylene wear (p <
0.001), which was in turn associated with a younger age (p = 0.01) and male gender (p <
0.001). The use of the Exeter metal-backed acetabular component was a notable failure with 12 of 32 hips (37.5%) revised for loosening. The Harris-Galante components failed with excessive wear, osteolysis and dislocation with 15% revised (5 of 33 hips). Only one of 23 hips with a cemented Elite component (4%) was revised for loosening and osteolysis. Our findings show that the Exeter Universal stem implanted outside the originating centre has excellent medium-term results.
Despite a lack of long-term follow-up, there
is an increasing trend towards using femoral heads of large diameter
in total hip replacement (THR), partly because of the perceived
advantage of lower rates of dislocation. However, increasing the
size of the femoral head is not the only way to reduce the rate
of dislocation; optimal alignment of the components and repair of
the posterior capsule could achieve a similar effect. In this prospective study of 512 cemented unilateral THRs (Male:Female
230:282) performed between 2004 and 2011, we aimed to determine
the rate of dislocation in patients who received a 22 mm head on
a 9/10 Morse taper through a posterior approach with capsular repair
and using the transverse acetabular ligament (TAL) as a guide for the
alignment of the acetabular component. The mean age of the patients
at operation was 67 years (35 to 89). The mean follow-up was 2.8
years (0.5 to 6.6). Pre- and post-operative assessment included
Oxford hip, Short Form-12 and modified University of California
Los Angeles and Merle D’Aubigne scores. The angles of inclination
and anteversion of the acetabular components were measured using
radiological software. There were four dislocations (0.78%), all
of which were anterior. In conclusion, THR with a 22 mm diameter head performed through
a posterior approach with capsular repair and using the TAL as a
guide for the alignment of the acetabular component was associated
with a low rate of dislocation. Cite this article:
The June 2014 Research Roundup360 looks at:Intraoperative irrigation a balance of toxicities; Ibandronate effective in bone marrow oedema; Risk stratification in damage control surgery; Osteoblast like cells potentially safe; Better wear and antibacterial?; Assessing outcomes in hip fracture.
Obesity is a global epidemic of 2.1 billion people and a well known cause of osteoarthritis. Joint replacement in the obese attracts more complications, poorer outcomes and higher revision rates. It is a reversible condition and the fundamental principles of dealing with reversible medical conditions prior to elective total joint replacement should apply to obesity. The dilemma for orthopaedic surgeons is when to offer surgery in the face of a reversible condition, which if treated may obviate joint replacement and reduce the risk and severity of obesity related disease in both the medical arena and the field of orthopaedics.
In this systematic review, our aim was to explore
whether or not patients are able to return to athletic activity
following lower limb joint replacement. We also investigated any evidence
as to whether participation in athletic activity post-joint replacement
increases complications and reduces implant survival. A PubMed, Embase and Sports Discus search was performed using
the MeSH terms ‘Sport’, ‘Athletic’, ‘Athlete’, ‘Physical’, ‘Activity’,
‘Arthroplasty’, ‘Total Hip Replacement’, ‘Hip Resurfacing’, ‘Total
Knee Replacement’, ‘Unicompartmental Knee Replacement’ and ‘Unicondylar
Knee Replacement’. From this search, duplications were excluded,
the remaining abstracts were reviewed and any unrelated to the search
terms were excluded. The remaining abstracts had their full papers
reviewed. Following joint replacement, participation in sporting activity
is common principally determined by pre-operative patient activity
levels, BMI and patient age. The type of joint replaced is of less
significance. Total time spent performing activity does not change
but tends to be at a lower intensity. There is little evidence in
the literature of an association between high activity levels and
early implant failure. Cite this article:
This is a longitudinal study of the daily urinary output and the concentrations in whole blood of cobalt and chromium in patients with metal-on-metal resurfacings over a period of four years. Twelve-hour urine collections and whole blood specimens were collected before and periodically after a Birmingham hip resurfacing in 26 patients. All ion analyses were carried out using a high-resolution inductively-coupled plasma mass spectrometer. Clinical and radiological assessment, hip function scoring and activity level assessment revealed excellent hip function. There was a significant early increase in urinary metal output, reaching a peak at six months for cobalt and one year for chromium post-operatively. There was thereafter a steady decrease in the median urinary output of cobalt over the following three years, although the differences are not statistically significant. The mean whole blood levels of cobalt and chromium also showed a significant increase between the pre-operative and one-year post-operative periods. The blood levels then decreased to a lower level at four years, compared with the one-year levels. This late reduction was statistically significant for chromium but not for cobalt. The effects of systemic metal ion exposure in patients with metal-on-metal resurfacing arthroplasties continue to be a matter of concern. The levels in this study provide a baseline against which the
The April 2014 Research Roundup360 looks at: scientific writing needed in orthopaedic papers; antiseptics and osteoblasts; thromboembolic management in orthopaedic patients; nicotine and obesity in post-operative complications; defining the “Patient Acceptable Symptom State”; and cheap and nasty implants of poor quality.
We reviewed the seven- to ten-year results of our previously reported prospective randomised controlled trial comparing total hip replacement and hemiarthroplasty for the treatment of displaced intracapsular fracture of the femoral neck. Of our original study group of 81 patients, 47 were still alive. After a mean follow up of nine years (7 to 10) overall mortality was 32.5% and 51.2% after total hip replacement and hemiarthroplasty, respectively (p = 0.09). At 100 months postoperatively a significantly greater proportion of hemiarthroplasty patients had died (p = 0.026). Three hips dislocated following total hip replacement and none after hemiarthroplasty. In both the total hip replacement and hemiarthroplasty groups a deterioration had occurred in walking distance (p = 0.02 and p <
0.001, respectively). One total hip replacement required revision compared with four hemiarthroplasties which were revised to total hip replacements. All surviving patients with a total hip replacement demonstrated wear of the cemented polyethylene component and all hemiarthroplasties had produced acetabular erosion. There was lower mortality (p = 0.013) and a trend towards superior function in patients with a total hip replacement in the medium term.
We audited the relationship between obesity and the age at which hip and knee replacement was undertaken at our centre. The database was analysed for age, the Oxford hip or knee score and the body mass index (BMI) at the time of surgery. In total, 1369 patients were studied, 1025 treated by hip replacement and 344 by knee replacement. The patients were divided into five groups based on their BMI (normal, overweight, moderately obese, severely obese and morbidly obese). The difference in the mean Oxford score at surgery was not statistically significant between the groups (p >
0.05). For those undergoing hip replacement, the mean age of the morbidly obese patients was ten years less than that of those with a normal BMI. For those treated by knee replacement, the difference was 13 years. The age at surgery fell significantly for those with a BMI >
35 kg/m2 for both hip and knee replacement (p >
0.05). This association was stronger for patients treated by knee than by hip replacement.
We report a 12- to 15-year implant survival assessment
of a prospective single-surgeon series of Birmingham Hip Resurfacings
(BHRs). The earliest 1000 consecutive BHRs including 288 women (335
hips) and 598 men (665 hips) of all ages and diagnoses with no exclusions
were prospectively followed-up with postal questionnaires, of whom
the first 402 BHRs (350 patients) also had clinical and radiological
review. Mean follow-up was 13.7 years (12.3 to 15.3). In total, 59 patients
(68 hips) died 0.7 to 12.6 years following surgery from unrelated
causes. There were 38 revisions, 0.1 to 13.9 years (median 8.7)
following operation, including 17 femoral failures (1.7%) and seven
each of infections, soft-tissue reactions and other causes. With
revision for any reason as the end-point Kaplan–Meier survival analysis
showed 97.4% (95% confidence interval (CI) 96.9 to 97.9) and 95.8%
(95% CI 95.1 to 96.5) survival at ten and 15 years, respectively.
Radiological assessment showed 11 (3.5%) femoral and 13 (4.1%) acetabular
radiolucencies which were not deemed failures and one radiological
femoral failure (0.3%). Our study shows that the performance of the BHR continues to
be good at 12- to 15-year follow-up. Men have better implant survival
(98.0%; 95% CI 97.4 to 98.6) at 15 years than women (91.5%; 95%
CI 89.8 to 93.2), and women <
60 years (90.5%; 95% CI 88.3 to
92.7) fare worse than others. Hip dysplasia and osteonecrosis are
risk factors for failure. Patients under 50 years with osteoarthritis
fare best (99.4%; 95% CI 98.8 to 100 survival at 15 years), with
no failures in men in this group. Cite this article:
Intravenous tranexamic acid (TXA) has been shown
to be effective in reducing blood loss and the need for transfusion
after joint replacement. Recently, there has been interest in applying
it topically before the closure of surgical wounds. This has the
advantages of ease of application, maximum concentration at the
site of bleeding, minimising its systemic absorption and, consequently,
concerns about possible side-effects. We conducted a systematic review and meta-analysis which included
14 randomised controlled trials (11 in knee replacement, two in
hip replacement and one in both) which investigated the effect of
topical TXA on blood loss and rates of transfusion. Topical TXA
significantly reduced the rate of blood transfusion (total knee
replacement: risk ratio (RR) 4.51; 95% confidence interval (CI):
3.02 to 6.72; p <
0.001 (nine trials, I2 = 0%); total
hip replacement: RR 2.56; 95% CI: 1.32 to 4.97, p = 0.004 (one trial)).
The rate of thromboembolic events with topical TXA were similar
to those found with a placebo. Indirect comparison of placebo-controlled
trials of topical and intravenous TXA indicates that topical administration
is superior to the intravenous route. In conclusion, topical TXA is an effective and safe method of
reducing the need for blood transfusion after total knee and hip
replacement. Further research is required to find its optimum dose
for topical use. Cite this article:
The lack of a consensus for core health outcomes
that should be reported in clinical research has hampered study design
and evidence synthesis. We report a United Kingdom consensus for
a core outcome set (COS) for clinical trials of patients with a
hip fracture. We adopted a modified nominal group technique to derive consensus
on 1) which outcome domains should be measured, and 2) methods of
assessment. Participants reflected a diversity of perspectives and
experience. They received an evidence synthesis and postal questionnaire
in advance of the consensus meeting, and ranked the importance of
candidate domains and the relevance and suitability of short-listed
measures. During the meeting, pre-meeting source data and questionnaire
responses were summarised, followed by facilitated discussion and
a final plenary session. A COS was determined using a closed voting
system: a 70% consensus was required. Consensus supported a five-domain COS: mortality, pain, activities
of daily living, mobility, and health-related quality of life (HRQL).
Single-item measures of mortality and mobility (indoor/outdoor walking
status) and a generic multi-item measure of HRQL - the EuroQoL EQ-5D
- were recommended. These measures should be included as a minimum
in all hip fracture trials. Other outcome measures should be added
depending on the particular interventions being studied. Cite this article:
The December 2013 Hip &
Pelvis Roundup360 looks at: Enhanced recovery works; Acetabular placement; Exercise better than rest in osteoarthritis patients; if Birmingham hip resurfacing is immune from pseudotumour; HIV and arthroplasty; Labral tears revisited; Prophylactic surgery for FAI; and Ceramics and impaction grafting
Fractures of the proximal femur are one of the
greatest challenges facing the medical community, constituting a
heavy socioeconomic burden worldwide. Controversy exists regarding
the optimal treatment for patients with unstable trochanteric proximal
femoral fractures. The recognised treatment alternatives are extramedullary
fixation usually with a sliding hip screw and intramedullary fixation
with a cephalomedullary nail. Current evidence suggests that best
results and lowest complication rates occur using a sliding hip screw.
Complications in these difficult fractures are relatively common
regardless of type of treatment. We believe that a novel device,
the X-Bolt dynamic plating system, may offer superior fixation over
a sliding hip screw with lower reoperation risk and better function.
We therefore propose to investigate the clinical effectiveness of
the X-bolt dynamic plating system compared with standard sliding
hip screw fixation within the framework of a the larger WHiTE (Warwick
Hip Trauma Evaluation) Comprehensive Cohort Study. Cite this article:
The ideal acetabular component is characterised by reliable, long-term fixation with physiological loading of bone and a low rate of wear. Trabecular metal is a porous construct of tantalum which promotes bony ingrowth, has a modulus of elasticity similar to that of cancellous bone, and should be an excellent material for fixation. Between 2004 and 2006, 55 patients were randomised to receive either a cemented polyethylene or a monobloc trabecular metal acetabular component with a polyethylene articular surface. We measured the peri-prosthetic bone density around the acetabular components for up to two years using dual-energy x-ray absorptiometry. We found evidence that the cemented acetabular component loaded the acetabular bone centromedially whereas the trabecular metal monobloc loaded the lateral rim and behaved like a hemispherical rigid metal component with regard to loading of the acetabular bone. We suspect that this was due to the peripheral titanium rim used for the mechanism of insertion.
The Kent hip is a distally-locked femoral stem which was developed to address severe proximal bone loss, severe bony deformity and peri-prosthetic fracture. We reviewed the results of 145 consecutive Kent hips implanted into 141 patients between 1987 and 2000. The indications for implantation were aseptic loosening (75 hips), septic loosening (two), peri-prosthetic and prosthetic fracture (37), severe bony deformity (24), and fracture through a proximal femoral metastasis (seven). The median time to full weight-bearing after surgery was two days and the mean length of follow-up was 5.1 years (2 to 15). Further revisions were required for 13 femoral stems. With removal of the stem for any reason as an end-point, the cumulative survival at five, ten and 15 years was 93%, 89% and 77%, respectively. In patients aged ≥ 70 years, the cumulative survival at 15 years was 92%, compared with 68% in those aged <
70 years. Because of these findings, we recommend the use of interlocking stems in patients aged ≥ 70 years, particularly in those with a peri-prosthetic fracture, for whom alternative methods are limited. Outcome scores and survival data, compared with other systems, indicate that the Kent hip should be used with caution in younger patients.
We report the survival at five years of 144 consecutive metal-on-metal resurfacings of the hip implanted between August 1997 and May 1998. Failure was defined as revision of either the acetabular or femoral component for any reason during the study period. The survival at the end of five years was 98% overall and 99% for aseptic revisions only. The mean age of the patients at implantation was 52.1 years. Three femoral components failed during the first two years, two were infected and one fractured. A single stage revision was carried out in each case. No other revisions were performed or are impending. No patients were lost to follow-up. Four died from unrelated causes during the study period. This study confirms that hip resurfacing using a metal-on-metal bearing of known provenance can provide a solution in the medium term for the younger more active adult who requires surgical intervention for hip disease.