Reconstruction with a cage outlives patients with metastatic disease involving the acetabulum.

AIM: The aim of this study was to determine whether patients treated with a caged reconstruction for metastatic acetabular disease would have a construct survival superior to that of their life expectancy. PATIENTS AND METHODS: We undertook a retrospective study, in a single centre in the United Kingdom, reviewing outcomes for 19 patients (20 hips) treated with a cage reconstruction for metastatic disease of their acetabulum over 6 years. Inclusion criteria were those with an impending fracture of the acetabulum, metastatic dissociation, fracture of the acetabulum and or femur and those whose life expectancy was considered by the oncology team to be >6 months. RESULTS: In all patients the Restoration GAP II acetabular cage (Stryker, Howmedica Osteonics Corp, NJ, USA) was used in conjunction with a cemented acetabular cup and cemented femoral stem. The mean age at the time of surgery was 68 (44-87) years with breast cancer being the most common primary malignancy (31%) followed by prostate cancer (26%).Radiological survivorship estimates were 94.1% (95% CI, 99.2-65.0) at 12 and 24 months, 70.6% (95% CI, 93.6-16.0) at 36 months and 35.3% (95% CI, 78.2-1.2) at 48 months. There were 3 radiological failures of the implant due to disease progression. Complications occurred in 3 patients with 2 developing deep infection which was treated with suppressive antibiotic therapy following aspiration of the hip. 1 patient suffered a hip dislocation following trauma which was successfully reduced closed and no further intervention was required. CONCLUSIONS: This study represents the first published case series of the use of the GAP II cage in patients with metastatic acetabular disease. The construct generally outlives the patient and hence is suitable for the treatment of acetabular metastases.

A systematic review and meta-analysis of survivorship and wear rates of metal and ceramic heads articulating with polyethylene liners in total hip arthroplasty.

BACKGROUND: The major joint registries report better survivorship for ceramic on polyethylene over metal on polyethylene bearings in total hip arthroplasty and it is generally accepted that this is due to a lower polyethylene wear rate. We used evidence synthesis to compare survivorship, polyethylene wear rates and metal ion levels for metal-on-polyethylene (MoP) and ceramic-on-polyethylene (CoP) bearings. If wear rates are not dissimilar in vivo this difference in revision rate may have another cause. Modular junctions are a potential source of corrosion and it is postulated that this may result in higher revision rates. METHODS: We performed a systematic review and meta-analysis comparing the survivorship of MoP and CoP bearings. Odds ratio (95% CI) of revision was calculated. Mean difference (MD) and 95% confidence intervals (CI) were used to compare secondary outcomes of polyethylene wear and metal ion levels. Meta-analysis was performed with a Mantel-Haenszel Random-Effects Model. RESULTS: 6 randomised controlled trials were included. There was no statistically significant difference between MoP and CoP revision rate (OR 1.04; 95% CI, 0.37-2.90, I2 = 0%, p = 0.94), linear bearing wear (MD 0.00 mm; 95% CI, -0.05 -0.05, I2 = 98%, p = 0.90), nor volumetric bearing wear (MD 33.57 mm3; 95% CI, -215.56-282.70, I2 = 98%, p = 0.79). No studies evaluated metal ion levels. CONCLUSIONS: We found no evidence of a difference in revision rates nor linear and volumetric wear between MoP and CoP bearings in the randomised controlled trials currently available. Our study therefore does not advocate the additional cost associated with the use of ceramic heads in combination with polyethylene bearings in order to minimise revision rates. This contrasts the findings of in vitro studies and the major joint registries.

Patient with native valve infective endocarditis and concomitant bacterial myopericarditis.

A 39-year-old man with known mitral regurgitation (MR) presented with chest pain, nausea and dizziness. Troponin of 5801 ng/L and scooped ST segments indicated myopericarditis. Cardiac MRI demonstrated an epicardial late gadolinium enhancement pattern consistent with a significantly myocarditic syndrome. Initially afebrile, the patient reported fevers a week earlier when abroad where he received amoxicillin.The patient then began spiking temperatures and infective endocarditis (IE) was confirmed following blood cultures positive for Streptococcus sanguinis and Transoesophageal echocardiography (TOE) showing a vegetation on the anterior mitral valve leaflet. Patient underwent 6 weeks of intravenous benzylpenicillin and on resolution he was discharged to await valve surgery.A model is proposed where septic embolism from IE caused bacterial myopericarditis, triggering the initial presenting complaint. It is suggested that prior antibiotic therapy and paracetamol suppressed the systemic symptoms of IE.

The relationship between the contralateral collateral supply and myocardial viability on cardiovascular magnetic resonance: can the angiogram predict functional recovery?

BACKGROUND: A collateral circulation which supplies a myocardial territory, subtended by a chronic total occlusion (CTO), may be observed at invasive coronary angiography. The prognostic and protective role of such collateralisation is well demonstrated suggesting that a good collateral circulation may be a predictor of myocardial viability, but current evidence is discrepant. The aim of this study is to assess the relationship between collateralisation from the contralateral epicardial vessels and myocardial viability by cardiovascular magnetic resonance (CMR). METHOD: Consecutive patients with CTO having had both CMR and invasive coronary angiography were retrospectively identified. The collateral circulation was graded with the Cohen and Rentrop classification. CMR images were graded per segment for wall motion (1: normal/hyperkinetic, 2: hypokinetic, 3: akinetic, or 4: dyskinetic) and wall motion score index (WMSI) was calculated. The segmental transmurality of late gadolinium enhancement was scored as 1 (0%), 2 (1-25%), 3 (26-50%), 4 (51-75%) and 5 (76-100%). RESULTS: A good collateral circulation was more likely to supply viable myocardium (p=0.01). There was no relationship between collateral circulation supply and wall motion score index (WMSI), however, increasing transmurality of LGE was significantly associated with higher mean WMSI representing increasing dysfunctional myocardium (p<0.001). CONCLUSION: The presence of collateral coronary circulation at angiography predicts the presence of viability on cardiovascular MRI, with a gradation of greater viability associated with improving Rentrop grade. A collateral circulation at angiography should, therefore, prompt more formal assessment of viability and consideration of revascularisation in order for the patient to obtain the associated functional and prognostic improvement.

Cardiac imaging to investigate suspected cardiac pain in the post-treadmill era.

Symptomatic cardiovascular disease is one of the leading causes of hospital admissions in the UK; along with emergency attendances, over 100,000 patients are investigated using treadmill testing via rapid access chest pain clinics each year. With the introduction of new technologies, clinicians have a wide choice of investigations including nuclear perfusion scanning, dobutamine stress echocardiography, cardiac computed tomography and stress cardiac magnetic resonance imaging. These imaging modalities have their strengths and weaknesses, which depend not only on the pre-test likelihood of significant coronary artery disease but also the clinical characteristics of the patient. This article will review the differing imaging modalities, the patient experience, accuracy, prognostic data and future prospects for cardiac computed tomography and magnetic resonance imaging.

Arthroscopic triple fusion joint preparation using two lateral portals: a cadaveric study to evaluate efficacy and safety.

BACKGROUND: Arthroscopic triple fusion has several advantages over open techniques, but its use has yet to become widespread. Preliminary published techniques use five portals with neurovascular risk. Our aim was to assess the safety and efficacy of an alternative lateral two portal technique. METHODS: Four cadaveric hindfeet were arthroscopically prepared for a triple fusion using two lateral portals. The distance to relevant subcutaneous nerves was measured as well as the prepared joint surface percentage. RESULTS: Mean distance from mid-lateral portal to the nearest sural nerve branch was 22.3mm (range 20-24mm) and from the dorsolateral portal to the intermediate branch of the superficial peroneal nerve was 7.8mm (range 4-11mm). Mean percentages of joint preparation were 63% (talar head), 62% (navicular), 75% (calcaneum) and 74% (cuboid). CONCLUSIONS: Two lateral arthroscopic portals allow adequate joint preparation for triple fusion procedures. The proximity of subcutaneous nerves is important to appreciate when using these portals.

Safety and feasibility of dobutamine stress cardiac magnetic resonance for cardiovascular assessment prior to renal transplantation.

AIMS: Current guidelines recommend cardiovascular risk assessment prior to renal transplantation. There is currently no evidence for the role of cardiovascular magnetic resonance (CMR) in this population, despite an established evidence base in the non-chronic kidney disease (CKD) population. Our aim is to determine the feasibility and safety of dobutamine stress CMR (DSCMR) imaging in the risk stratification of CKD patients awaiting renal transplantation. METHODS: CKD patients who were deemed at high risk for coronary artery disease (CAD) and awaiting renal transplantation underwent DSCMR. RESULTS: Forty-one patients whose median age was 56 years (range 28­73 years) underwent DSCMR. Nineteen were undergoing haemodialysis, 10 peritoneal dialysis and 12 pre-dialysis. The aetiology of the renal failure was diabetes mellitus in 29%, glomerulonephritis in 24%, hypertension in 22% and autosomal dominant polycystic kidney disease in 10%. Thirty-eight patients (93%) achieved the end point, either positive for ischaemia or negative, achieving at least 85% of age-predicted heart rate. Two of them did not achieve target heart rate and one was discontinued because of severe headache. Of the 38 patients who achieved the end point, 35 (92%) were negative for inducible wall motion abnormalities and four (10%) were positive. There were no serious adverse effects. CONCLUSION: DSCMR is a well tolerated and viable investigation for the cardiovascular risk stratification of high-risk CKD patients prior to renal transplantation. DSCMR already has an established evidence base in the non-CKD population with superiority over other noninvasive techniques. Larger studies with outcome data are now required to define its true utility in the CKD population.

Multimodality imaging in bland-White-Garland syndrome in an adult with a left dominant coronary artery system.

Bland-White-Garland syndrome, also known as anomalous origin of the left coronary artery from the pulmonary artery, is a rare congenital disorder affecting around one in 300,000 live births. The majority of these present within the first year of life with 90% mortality rate if untreated and consequently is an extremely rare presentation in the adult. We present the first published case with a left dominant system in an adult presenting in their late 20s, illustrated by multimodality imaging.

Stage 3 pyomyositis of the gluteus minimus; Staphylococcus aureus sepsis, autoanticoagulation, proximal femoral osteomyelitis and the role of surgical intervention.

Primary pyomyositis is a rare bacterial infection of the skeletal muscle. Traditionally a tropical disease, it is increasingly described in westernised urban populations. The aetiology is due to transient bacteraemia in the presence of risk factors such as traumatised muscle, or immunocompromise. The condition presents in one of three stages, representing progression of disease severity. Intravenous antibiotic therapy is often sufficient for this disease at its early stage, but surgical drainage is necessary for advanced presentations. We report a severe case of stage 3 pyomyositis of the gluteus minimus, which led to Staphylococcus aureus sepsis, deranged liver function, acute kidney injury, autoanticoagulation and proximal femoral osteomyelitis in a healthy 64-year-old Caucasian man. This illustrates the potential severity of the disease, the life-threatening sequelae when diagnosis is delayed and the role of surgical drainage in averting the progression of systemic sepsis to end-organ dysfunction, disseminated intravascular coagulation and potentially death.

An unusual cause of Grey Turner's sign.

A woman in her late 70s presented to the acute general surgical take with a 3-day history of worsening right leg pain and swelling. She had undergone right revision total hip arthroplasty 20 months previously and reported chronic postoperative right thigh pain attributed to a femoral deep venous thrombosis for which she had been warfarinised. On examination, Grey Turner's sign (bruising of the flanks indicating retroperitoneal haemorrhage) was present, as well as a large tender mass in the right iliac fossa and pitting oedema throughout the right lower limb. Urgent CT scan with intravenous contrast revealed a right retroperitoneal haematoma secondary to a right acetabular screw protruding into the right external iliac vein. The patient was successfully managed with warfarin reversal and surgical removal of the relevant acetabular screw. At 2-month follow-up, the patient's symptoms continue to resolve.

In vitro and preliminary in vivo validation of echo particle image velocimetry in carotid vascular imaging.

Noninvasive, easy-to-use and accurate measurements of wall shear stress (WSS) in human blood vessels have always been challenging in clinical applications. Echo particle image velocimetry (Echo PIV) has shown promise for clinical measurements of local hemodynamics and wall shear rate. Thus far, however, the method has only been validated under simple flow conditions. In this study, we validated Echo PIV under in vitro and in vivo conditions. For in vitro validation, we used an anatomically correct, compliant carotid bifurcation flow phantom with pulsatile flow conditions, using optical particle image velocimetry (optical PIV) as the reference standard. For in vivo validation, we compared Echo PIV-derived 2-D velocity fields obtained at the carotid bifurcation in five normal subjects against phase-contrast magnetic resonance imaging (PC-MRI)-derived velocity measurements obtained at the same locations. For both studies, time-dependent, 2-D, two-component velocity vectors; peak/centerline velocity, flow rate and wall shear rate (WSR) waveforms at the common carotid artery (CCA), carotid bifurcation and distal internal carotid artery (ICA) were examined. Linear regression, correlation analysis and Bland-Altman analysis were used to quantify the agreement of different waveforms measured by the two techniques. In vitro results showed that Echo PIV produced good images of time-dependent velocity vector maps over the cardiac cycle with excellent temporal (up to 0.7 ms) and spatial (∼0.5 mm) resolutions and quality, comparable with optical PIV results. Further, good agreement was found between Echo PIV and optical PIV results for velocity and WSR measurements. In vivo results also showed good agreement between Echo PIV velocities and phase contrast MRI velocities. We conclude that Echo PIV provides accurate velocity vector and WSR measurements in the carotid bifurcation and has significant potential as a clinical tool for cardiovascular hemodynamics evaluation.