The first 325 Exeter Universal stems (309 patients) implanted at the originating centre were inserted between March 1988 and February 1990 by a group of surgeons with differing experience. In this report we describe the clinical and radiological results at a mean of 15.7 years (14.7 to 17.3) after operation with no loss to follow-up. There were 97 patients (108 hips) with replacements still in situ and 31 (31 hips) who had undergone a further procedure. With an endpoint of revision for aseptic loosening, the survivorship at 17 years was 100% and 90.4% for the femoral and acetabular component, respectively. The mean Merle D’Aubigné and Postel scores at review were 5.4 (
Antibiotic prophylaxis is routinely administered during joint replacement surgery and may predispose patients to
Systemic mastocytosis is a rare condition that often involves the bone marrow. We report the case of a patient with systemic mastocytosis who underwent total hip replacement. Technical difficulties encountered during the procedure included a narrow medullary canal and abnormally hard bone, later confirmed by laboratory measurements. Follow-up at five years showed a good clinical and radiological outcome.
Infection remains a significant and common complication after joint replacement and there is debate about which contributing factors are important. Few studies have investigated the effect of the operating time on infection. We collected data prospectively from 5277 hip and knee replacements which included the type of procedure, the operating time, the use of drains, the operating theatre, surgeon, age and gender. In a subgroup of 3449 knee replacements further analysis was carried out using the tourniquet time in place of the operating time. These variables were assessed by the use of generalised linear modelling against superficial, deep or joint-space post-operative infection as defined by the Australian Surgical-Site Infection criteria. The overall infection rate was 0.98%. In the replacement data set both male gender (z = 3.097, p = 0.00195) and prolonged operating time (z = 4.325, p <
0.001) were predictive of infection. In the knee subgroup male gender (z = 2.250, p = 0.02447), a longer tourniquet time (z = 2.867, p = 0.00414) and total knee replacement ( These findings support the view that a prolonged operating time and male gender are associated with an increased incidence of infection. Steps to minimise intra-operative delay should be instigated, and care should be exercised when introducing measures which prolong the duration of joint replacement.
Periosteum is important for bone homoeostasis
through the release of bone morphogenetic proteins (BMPs) and their
effect on osteoprogenitor cells. Smoking has an adverse effect on
fracture healing and bone regeneration. The aim of this study was
to evaluate the effect of smoking on the expression of the BMPs
of human periosteum. Real-time polymerase chain reaction was performed
for BMP-2,-4,-6,-7 gene expression in periosteal samples obtained from
45 fractured bones (19 smokers, 26 non-smokers) and 60 non-fractured
bones (21 smokers, 39 non-smokers). A hierarchical model of BMP
gene expression (BMP-2 >
BMP-6 >
BMP-4 >
BMP-7) was demonstrated
in all samples. When smokers and non-smokers were compared, a remarkable
reduction in the gene expression of BMP-2, -4 and -6 was noticed
in smokers. The comparison of fracture and non-fracture groups demonstrated
a higher gene expression of BMP-2, -4 and -7 in the non-fracture
samples. Within the subgroups (fracture and non-fracture), BMP gene
expression in smokers was either lower but without statistical significance
in the majority of BMPs, or similar to that in non-smokers with
regard to BMP-4 in fracture and BMP-7 in non-fracture samples. In
smokers, BMP gene expression of human periosteum was reduced, demonstrating
the effect of smoking at the molecular level by reduction of mRNA
transcription of periosteal BMPs. Among the BMPs studied, BMP-2
gene expression was significantly
Radiostereometric analysis (RSA) can detect early
micromovement in unstable implant designs which are likely subsequently
to have a high failure rate. In 2010, the Articular Surface Replacement
(ASR) was withdrawn because of a high failure rate. In 19 ASR femoral
components, the mean micromovement over the first two years after implantation
was 0.107 mm ( We conclude that the ASR femoral component achieves initial stability
and that early migration is not the mode of failure for this resurfacing
arthroplasty.
We present a comparison of patient-reported outcomes
(PROMs) in relation to patient age, in patients who had received
a total (TKR) or unicompartmental knee replacement (UKR). The outcome
was evaluated using the Oxford knee score (OKS), EuroQol (EQ-5D)
and satisfaction scores. Patients aged 65 to 84 years demonstrated
better pre-operative function scores than those aged <
65 years
(OKS, p = 0.03; EQ-5D, p = 0.048) and those aged
≥ 85 years (OKS, p = 0.03). Post-operative scores were comparable
across age groups, but a linear trend for greater post-operative
improvement in OKS and EQ-5D was seen with decreasing age (p <
0.033). The overall mean satisfaction score at six months was 84.9,
but those aged <
55 years exhibited a lower mean level of satisfaction (78.3)
compared with all other age groups (all p <
0.031). The cumulative
overall two-year revision rate was 1.3%. This study demonstrates
that good early outcomes, as measured by the OKS and EQ-5D, can
be anticipated following knee replacement regardless of the patient’s
age, although younger patients gain greater improvement. However,
the lower satisfaction in those aged
<
55 years is a concern, and suggests that outcome is not fully
encapsulated by the OKS and EQ-5D evaluation, and raises the question
whether the OKS alone is an appropriate measure of pain and function
in younger, more active individuals. Cite this article:
Progressive retroversion of a cemented stem is
predictive of early loosening and failure. We assessed the relationship
between direct post-operative stem anteversion, measured with CT,
and the resulting rotational stability, measured with repeated radiostereometric
analysis over ten years. The study comprised 60 cemented total hip
replacements using one of two types of matt collared stem with a
rounded cross-section. The patients were divided into three groups
depending on their measured post-operative anteversion (<
10°,
10° to 25°, >
25°). There was a strong correlation between direct
post-operative anteversion and later posterior rotation. At one
year the <
10° group showed significantly more progressive retroversion
together with distal migration, and this persisted to the ten-year
follow-up. In the <
10° group four of ten stems (40%) had been
revised at ten years, and an additional two stems (20%) were radiologically
loose. In the ‘normal’ (10° to 25°) anteversion group there was
one revised (3%) and one loose stem (3%) of a total of 30 stems,
and in the >
25° group one stem (5%) was revised and another loose (5%)
out of 20 stems. This poor outcome is partly dependent on the design
of this prosthesis, but the results strongly suggest that the initial
rotational position of cemented stems during surgery affects the
subsequent progressive retroversion, subsidence and eventual loosening.
The degree of retroversion may be sensitive to prosthetic design
and stem size, but <
10° of anteversion appears deleterious to
the long-term outcome for cemented hip prosthetic stems. Cite this article:
Heterotopic ossification following joint replacement in the lower limb occurs in 3% to 90% of cases. Higher grades of heterotopic ossification can result in significant limitation of function and can negate the benefits of joint replacement. The understanding of the pathophysiology of this condition has improved in recent years. It would appear to be related to a combination of systemic and local factors, including over-expression of bone morphogenetic protein-4. There is currently little evidence to support the routine use of prophylaxis for heterotopic ossification in arthroplasty patients, but prophylaxis is recommended by some for high-risk patients. Radiotherapy given as one dose of 7 Gy to 8 Gy, either pre-operatively (<
four hours before) or post-operatively (within 72 hours of surgery), appears to be more effective than indometacin therapy (75 mg daily for six weeks). In cases of prophylaxis against recurrent heterotopic ossification following excision, recent work has suggested that a combination of radiotherapy and indometacin is effective. Advances in our understanding of this condition may permit the development of newer, safer treatment modalities.
We report a systematic review and meta-analysis of published randomised controlled trials evaluating the efficacy of tranexamic acid (TXA) in reducing blood loss and transfusion in total hip replacement (THR). The data were evaluated using the generic evaluation tool designed by the Cochrane Bone, Joint and Muscle Trauma Group. We identified 11 clinical trials which were suitable for detailed extraction of data. There were no trials that used TXA in revision THR. A total of seven studies (comprising 350 patients) were eligible for the blood loss outcome data. The use of TXA reduced intra-operative blood loss by a mean of 104 ml (95% confidence interval (CI) −164 to −44, p = 0.0006, heterogeneity I2 0%), postoperative blood loss by a mean of 172 ml (95% CI −263 to −81, p = 0.0002, heterogeneity I2 63%) and total blood loss by a mean of 289 ml (95% CI −440 to −138, p <
0.0002, heterogeneity I2 54%). TXA led to a significant reduction in the proportion of patients requiring allogeneic blood transfusion (risk difference −0.20, 95% CI −0.29 to −0.11, p <
0.00001, I2 15%). There were no significant differences in deep-vein thrombosis, pulmonary embolism, infection rates or other complications among the study groups.
The inherent challenges of total hip replacement
(THR) in children include the choice of implant for the often atypical
anatomical morphology, its fixation to an immature growing skeleton
and the bearing surface employed to achieve a successful long-term
result. We report the medium-term results of 52 consecutive uncemented
THRs undertaken in
35 paediatric patients with juvenile idiopathic arthritis. The mean
age at the time of surgery was 14.4 years (10 to 16). The median
follow-up was 10.5 years (6 to 15). During the study period 13 THRs
underwent revision surgery. With revision as an endpoint, subgroup
analysis revealed 100% survival of the 23 ceramic-on-ceramic THRs
and 55% (16 of 29) of the metal- or ceramic-on-polyethylene. This
resulted in 94% (95% CI 77.8 to 98.4) survivorship of the femoral
component and 62% (95% CI 41.0 to 78.0) of the acetabular component.
Revision of the acetabular component for wear and osteolysis were
the most common reasons for failure accounting for 11 of the 13
revisions. The success seen in patients with a ceramic-on-ceramic articulation
seems to indicate that this implant strategy has the potential to
make a major difference to the long-term outcome in this difficult
group of patients.
Our aim in this pilot study was to evaluate the fixation of, the bone remodelling around, and the clinical outcome after surgery of a new, uncemented, fully hydroxyapatite-coated, collared and tapered femoral component, designed specifically for elderly patients with a fracture of the femoral neck. We enrolled 50 patients, of at least 70 years of age, with an acute displaced fracture of the femoral neck in this prospective single-series study. They received a total hip replacement using the new component and were followed up regularly for two years. Fixation was evaluated by radiostereometric analysis and bone remodelling by dual-energy x-ray absorptiometry. Hip function and the health-related quality of life were assessed using the Harris hip score and the EuroQol-5D. Up to six weeks post-operatively there was a mean subsidence of 0.2 mm (−2.1 to +0.5) and a retroversion of a mean of 1.2° (−8.2° to +1.5°). No component migrated after three months. The patients had a continuous loss of peri-prosthetic bone which amounted to a mean of 16% (−49% to +10%) at two years. The mean Harris hip score was 82 (51 to 100) after two years. The two-year results from this pilot study indicate that this new, uncemented femoral component can be used for elderly patients with osteoporotic fractures of the femoral neck.
We have investigated the effectiveness of the transplantation of bone-marrow-derived mononuclear cells (BMMNCs) with interconnected porous calcium hydroxyapatite (IP-CHA) on early bone repair for osteonecrosis of the femoral head. We studied 22 patients (30 hips) who had osteonecrosis with a minimum follow-up of one year after implantation of BMMNCs. The mean age at surgery was 41 years (18 to 64) and the mean period of follow-up was 29 months (19 to 48). In a control group, cell-free IP-CHA was implanted into a further eight patients (9 hips) with osteonecrosis of the femoral head and the outcomes were compared. A reduction in the size of the osteonecrotic lesion was observed subsequent to hypertrophy of the bone in the transition zone in the BMMNC group. In three patients in the treatment group progression to extensive collapse was detected. In the control group subtle bone hypertrophy was observed, but severe collapse of the femoral head occurred in six of eight hips. In this limited study the implantation of BMMNCs and IP-CHA appears to confer benefit in the repair of osteonecrosis and in the prevention of collapse.
Recent publication of reports showing high revision rates for hip and knee replacements carried out in Independent Sector Treatment Centres (ISTCs) has raised doubts regarding their ability to provide high quality healthcare. The high revision rates also create a financial burden to the NHS. The poor quality of data collected at ISTCs makes their performance difficult to evaluate. Funds may be better spent improving existing NHS facilities rather than establishing parallel ISTCs.
The August 2012 Knee Roundup360 looks at: meniscal defects and a polyurethane scaffold; which is best between a single or double bundle; OA of the knee; how to resolve anterior knee pain; whether yoga can be bad for your menisci; metal ions in the serum; whether ACI is any good; the ACL; whether hyaluronic acid delays collagen degradation; and hyaluronan and patellar tendinopathy.
Metal-on-metal total hip replacement has been targeted at younger patients with anticipated long-term survival, but the effect of the production of metal ions is a concern because of their possible toxicity to cells. We have reviewed the results of the use of the Ultima hybrid metal-on-metal total hip replacement, with a cemented polished tapered femoral component with a 28 mm diameter and a cobalt-chrome (CoCr) modular head, articulating with a 28 mm CoCr acetabular bearing surface secured in a titanium alloy uncemented shell. Between 1997 and 2004, 545 patients with 652 affected hips underwent replacement using this system. Up to 31 January 2008, 90 (13.8%) hips in 82 patients had been revised. Pain was the sole reason for revision in 44 hips (48.9%) of which 35 had normal plain radiographs. Peri-prosthetic fractures occurred in 17 hips (18.9%) with early dislocation in three (3.3%) and late dislocation in 16 (17.8%). Infection was found in nine hips (10.0%). At operation, a range of changes was noted including cavities containing cloudy fluid under pressure, necrotic soft tissues with avulsed tendons and denuded osteonecrotic upper femora. Corrosion was frequently observed on the retrieved cemented part of the femoral component. Typically, the peri-operative findings confirmed those found on pre-operative metal artefact reduction sequence MRI and histological examination showed severe necrosis. Metal artefact reduction sequence MRI proved to be useful when investigating these patients with pain in the absence of adverse plain radiological features.
We report the minimum five-year follow-up of 352 primary total hip replacements using the uncemented hydroxyapatite-coated ANCA-Fit femoral component with a modular neck and head. The series comprised 319 patients (212 men, 107 women) with a mean age at operation of 64.4 years (28 to 97). The principal diagnosis was osteoarthritis. A total of 18 patients (21 hips) died before their follow-up at five years, nine patients (11 hips) were lost to follow-up, and four (four hips) declined further follow-up. Patient-reported outcomes have been recorded for 288 patients (316 hips). Their mean Oxford Hip Score improved significantly from 41 points (16 to 57) pre-operatively to 20 points (12 to 44) at five-year follow-up. Radiological assessment showed good bony stability in 98% of implants. There were two cases of aseptic loosening of the femoral component. There were no clinical or radiological complications related to modularity. In our series we did not see the high rate of intra-operative fracture previously reported for this implant. This medium-term follow-up study demonstrates that the clinical outcome of the ANCA-Fit femoral component is, to date, comparable with that of other metaphyseal loading femoral components.
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
Allografts of bone from the femoral head are often used in orthopaedic procedures. Although the donated heads are thoroughly tested microscopically before release by the bone bank, some surgeons take additional cultures in the operating theatre before implantation. There is no consensus about the need to take these cultures. We retrospectively assessed the clinical significance of the implantation of positive-cultured bone allografts. The contamination rate at retrieval of the allografts was 6.4% in our bone bank. Intra-operative cultures were taken from 426 femoral head allografts before implantation; 48 (11.3%) had a positive culture. The most frequently encountered micro-organism was coagulase-negative staphylococcus. Deep infection occurred in two of the 48 patients (4.2%). In only one was it likely that the same micro-organism caused the contamination and the subsequent infection. In our study, the rate of infection in patients receiving positive-cultured allografts at implantation was not higher than the overall rate of infection in allograft surgery suggesting that the positive cultures at implantation probably represent contamination and that the taking of additional cultures is not useful.