Clinical outcomes of fast-track total knee arthroplasty for patients aged >80 years.

INTRODUCTION: Because of the ageing population in Hong Kong, there is an increasing incidence of total knee arthroplasties (TKA) conducted in patients aged >80 years. METHODS: This retrospective case-control study enrolled all patients who were aged >80 years and underwent fast-track primary TKA between 2011 and 2015. Their outcomes were compared with the outcomes of a matched control group of younger patients who underwent fast-track TKA in the same period. RESULTS: In total, 220 patients were included in this study with a follow-up period of at least 2 years (mean=3.2 years; range, 2-5 years); 112 (51%) were octogenarians and 108 (49%) were non-octogenarians. Greater improvement in Knee Society Score was found in the octogenarian group at 1 year after surgery (46 ± 19 vs 39 ± 16, P=0.018). The incidence of complications was higher in the octogenarian group (15.2% vs 4.6%, P=0.009). There were no significant differences in the incidence of major complications, the rate of intensive care unit admission, or the 1-year mortality rate between the two groups. After adjustment for confounding factors, Charlson Comorbidity Index >5, history of major cerebrovascular accident, and history of peptic ulcer disease were predictive of complications after fast-track TKA (P=0.039, P=0.016, and P=0.007, respectively); octogenarian status was not predictive of complications. CONCLUSIONS: Octogenarians had greater improvement in Knee Society Score at 1 year after fast-track TKA, compared with non-octogenarians, but there were no significant differences in the incidences of mortality or major complications.

Local infiltration analgesia in primary total knee arthroplasty.

INTRODUCTION: Postoperative pain in total knee arthroplasty (TKA) can hinder rehabilitation and cause morbidity. Local infiltration analgesia (LIA), comprising an anaesthetic drug, non-steroidal anti-inflammatory drug, and adrenaline, has been introduced to reduce pain and systemic side-effects. This study evaluated the efficacy of LIA in TKA with respect to morphine consumption and postoperative pain score. METHODS: This single-centre retrospective cohort study recruited patients with knee osteoarthritis who were scheduled for primary TKA during the period from January 2017 to December 2017. Patients with chronic inflammatory joint disease, contra-indications for LIA, or dementia were excluded. Patients in the LIA group were administered single-dose LIA intra-operatively, while those in the control group were not. Primary outcomes were postoperative pain score, morphine demand, and morphine consumption; secondary outcomes were range of motion, quadriceps power, and postoperative length of stay. RESULTS: In total, 136 patients were recruited (68 per group). Total postoperative morphine demand and consumption, as well as pain scores from postoperative day (POD) 1 to POD 4, were lower in the LIA group than in the control group. The range of motion from POD 1 to POD 4 and quadriceps power on POD 1 were higher in the LIA group than in the control group. Quadriceps power from POD 2 to POD 4 and postoperative length of stay were not significantly different between groups. CONCLUSIONS: Intra-operative single-dose LIA can effectively reduce postoperative pain, morphine demand, and morphine consumption. Therefore, the use of LIA is recommended during TKA.

Transarterial embolisation for congenital renal arteriovenous malformations improves clinical condition even with partial obliteration.

AIM: To evaluate the efficacy and safety of transarterial embolisation (TAE), used to treat congenital renal arteriovenous malformations (CRAVMs). MATERIALS AND METHODS: The medical records were searched retrospectively to identify patients who underwent TAE to treat CRAVM from January 2003 to August 2015. Patient demographics, clinical presentations, and imaging findings were reviewed. TAE outcomes, including complete or partial obliteration, clinical success, complications, renal function changes, and relapse of symptoms or signs after the final TAE, were assessed. RESULTS: Over the 12-year period, 16 patients (nine male, seven female; median age, 47 years) who underwent 21 TAE procedures to treat 16 CRAVMs were enrolled in the study. The most common clinical presentation was haematuria (81.3%). Thirteen patients (81.3%) had cirsoid and three (18.7%) had aneurysmal CRAVMs. Of the 16 CRAVMs, 11 (68.8%) were peripheral, four (25%) were central, and one (6.3%) was both peripheral and central. The complete obliteration rate was 56.3%. The clinical success rate was 87.5% over a median follow-up period of 398.5 days. Two (9.5%) major complications and 14 (66.7%) minor complications were encountered. No statistically significant change in renal function was evident after TAE. CONCLUSION: TAE was safe and effective when used to treat CRAVM; the complication profile was acceptable and renal function was preserved. TAE improved the clinical condition of CRAVM patients even when obliteration was only partial.

Predictive factors for length of hospital stay following primary total knee replacement in a total joint replacement centre in Hong Kong.

INTRODUCTION: The demand for total knee replacement in Hong Kong places tremendous economic burden on our health care system. Shortening hospital stay reduces the associated cost. The aim of this study was to identify perioperative predictors of length of hospital stay following primary total knee replacement performed at a high-volume centre in Hong Kong. METHODS: We retrospectively reviewed all primary total knee replacements performed at Yan Chai Hospital Total Joint Replacement Centre from October 2011 to October 2015. Perioperative factors that might influence length of stay were recorded. RESULTS: A total of 1622 patients were identified. The mean length of hospital stay was 6.8 days. Predictors of prolonged hospital stay following primary total knee replacement were advanced age; American Society of Anesthesiologists physical status class 3; bilateral total knee replacement; in-patient complications; and the need for blood transfusion, postoperative intensive care unit admission, and urinary catheterisation. CONCLUSIONS: Evaluating factors that can predict length of hospital stay is the starting point to improve our current practice in joint replacement surgery. Prediction of high-risk patients who will require a longer hospitalisation enables proactive discharge planning.

Mortality following primary total knee replacement in public hospitals in Hong Kong.

INTRODUCTION: More than 2000 total knee replacements are performed each year in Hong Kong and more than 10 000 patients are on the waiting list. How safe is total knee replacement, however? The aims of the study were to review the mortality of primary total knee replacement in public hospitals in Hong Kong and to identify risk factors for mortality in a high-volume hospital. METHODS: All primary total knee replacements performed in Hospital Authority hospitals and Yan Chai Hospital from October 2011 to September 2014 were reviewed. Case-control analysis was performed for risk factors of total all-cause mortality in total knee replacement at Yan Chai Hospital. RESULTS: There were 6588 patients in Hospital Authority hospitals and 1184 in Yan Chai Hospital (1095 unilateral and 89 bilateral total knee replacement). The mean follow-up time of patients in Yan Chai Hospital was 12.8 months. The mortality at 30 days, 90 days and 1 year was 0%, 0.08%, 0.34% for Yan Chai Hospital; and 0.1%, 0.2%, 0.7% for Hospital Authority hospitals, respectively. For Yan Chai Hospital, the mean operation-to-death interval was 21 months (range, 1-35 months). The mean age at death was 78 years and main causes were malignancy (50%) and pneumonia (21%). Predictors of mortality included age at surgery, American Society of Anesthesiologists class 3, and preoperative range of motion. Hospital surgery volume, preoperative co-morbidities, and postoperative deep vein thrombosis were not significant factors. CONCLUSIONS: Mortality after primary total knee replacement was low in public hospitals in Hong Kong. Patients of older age or poorer general well-being in terms of poor range of motion or American Society of Anesthesiologists class 3 should be in optimal health before surgery and counselled about the higher mortality rate. A citywide joint replacement registry may help monitor and analyse postoperative total knee replacement mortality specific to our locality.

MRI of the cervical spine with 3D gradient echo sequence at 3 T: initial experience.

AIM: The aim of this study was to compare three-dimensional (3D) high resolution T2*-weighted gradient echo (3D FFE) magnetic resonance (MR) sequence with conventional 2D T2-weighted turbo spin echo (TSE) MR sequence for imaging of the cervical spine, especially to assess the detectability of the internal anatomy of the cervical spinal cord, i.e. to distinguish the grey and white matter. METHODS: Fifteen volunteers were examined at 3.0T MR unit. Signal-to-noise (SNR), contrast-to-noise (CNR) and image homogeneity were evaluated. In the visual analysis, the visibility of anatomical structures of the cervical spine and artifacts were assessed. The nonparametric method of paired sample t-test was adopted to evaluate the differences between the sequences. RESULTS: The 3D FFE sequence provided better results for CNR, cerebrospinal fluid (CSF) versus white matter, grey matter, disk and bone. Moreover, it yielded good results for the CNR grey matter versus white matter. The butterfly-shaped "H" is clearly displayed in the 3D FFE sequence. The statistical analysis revealed the statistically significant difference between the 2D TSE and 3D FFE sequences for the contrast of CSF versus spinal cord (both grey matter and white matter). CONCLUSION: The 3D FFE sequence in MR imaging of the cervical spinal cord is superior in delineation of spinal cord anatomical structures compared to 2D TSE sequence.

Angiographic factors associated with haemorrhagic presentation of brain arteriovenous malformation in a Chinese paediatric population.

OBJECTIVE: To identify specific angiographic factors associated with haemorrhagic presentation of brain arteriovenous malformation in Chinese paediatric patients. DESIGN: Retrospective cross-sectional observational study. SETTING: Four locoregional tertiary neurosurgical centres in Hong Kong: Queen Elizabeth Hospital, Tuen Mun Hospital, Kwong Wah Hospital, and Pamela Youde Nethersole Eastern Hospital. PATIENTS: Patients aged 18 years or younger who underwent pretreatment digital subtraction angiography for brain arteriovenous malformation between 1 January 2005 and 31 July 2013 were included. Patients were divided into haemorrhagic and non-haemorrhagic groups based on the initial presentation. Pretreatment digital subtraction angiographies were independently reviewed by two experienced neuroradiologists. MAIN OUTCOME MEASURES: The following parameters were evaluated for their association with haemorrhagic presentation by univariate and multivariate analyses: nidus location, nidus size, nidus morphology (diffuse or compact); origin and number of arterial feeders; venous drainage; number of draining veins; presence of aneurysms, venous varices, and venous stenosis. RESULTS: A total of 67 children and adolescents (28 male, 39 female) with a mean age of 12 years were included. Of them, 52 (78%) presented with haemorrhage. Arteriovenous malformation size (P=0.004) and morphology (P=0.05) were found to be associated with haemorrhagic presentation by univariate analysis. Small arteriovenous malformation nidus size and diffuse nidal morphology were identified as independent risk factors for haemorrhage by multivariate analysis. CONCLUSION: Smaller arteriovenous malformation size and diffuse nidal morphology are angiographic factors independently associated with haemorrhagic presentation. Bleeding risk is important in determining the therapeutic approach (aggressive vs conservative) and timeframe, particularly in paediatric patients.

Predictive factors for early failure of transarterial embolization in blunt hepatic injury patients.

AIM: To evaluate the early success of transarterial embolization (TAE) in patients with traumatic liver haemorrhage and to determine independent factors for its failure. MATERIALS AND METHODS: From January 2009 to December 2012, TAE was performed in 48 patients for traumatic liver haemorrhage. Their medical charts were reviewed for demographic information, pre-TAE vital signs and laboratory data, injury grade, type of contrast medium extravasation (CME) at CT, angiography findings, and early failure. "Early failure" was defined as the need for repeated TAE or a laparotomy for hepatic haemorrhage within 4 days after TAE. Variables were compared between the early success and early failure groups. Variables with univariate significance were also analysed using multivariate logistic regression for predictors of early failure. RESULTS: Among 48 liver TAE cases, nine (18.8%) were early failures due to liver haemorrhage. Early failure was associated with injury grade (p = 0.039), major liver injury (grades 4 and 5; p = 0.007), multiple CMEs at angiography (p = 0.031), incomplete TAE (p = 0.002), and elevated heart rate (p = 0.026). Incomplete embolization (OR = 8; p = 0.042), and heart rate >110 beats/min (bpm; OR = 8; p = 0.05) were independent factors for early failure of TAE in the group with major liver injuries. CONCLUSION: Major hepatic injury is an important factor in early failure. Patients with a heart rate >110 bpm and incomplete embolization in the major injury group have an increased rate of early failure. The success rate of proximal TAE was comparable to that of the more time-consuming, superselective, distal TAE.

Elective unilateral total knee replacement using continuous femoral nerve blockade versus conventional patient-controlled analgesia: perioperative patient management based on a multidisciplinary pathway.

OBJECTIVES. To evaluate the effectiveness of our new multidisciplinary pathway for total knee replacement patients and compare outcomes after continuous femoral nerve blockade versus conventional patient-controlled analgesia for postoperative pain. DESIGN. Randomised controlled trial in a routine clinical setting. SETTING. Acute orthopaedic wards and operating theatres, Yan Chai Hospital, Hong Kong. PATIENTS. Sixty patients underwent elective unilateral total knee replacement under spinal anaesthesia from May 2009 to September 2011 and were randomly assigned to continuous femoral nerve blockade or conventional patient-controlled analgesia (30 patients in each group). MAIN OUTCOME MEASURES. Quality of pain control was evaluated by pain scores at rest and during mobilisation, opioid consumption, frequency of side-effects, and patient satisfaction score. Rehabilitation progress was assessed according to the day of first starting weight-bearing exercise, day of independent walking in the ward with aid, Timed Up and Go test, and time elapsing till discharge. Surgical outcome was assessed by the Knee Society score 6 months after discharge, re-admissions, and occurrence of complications. RESULTS. Patients having continuous femoral nerve blockade tended to have less pain on movement and achieved earlier mobilisation than those having patient-controlled analgesia. The former group consumed less opioids, had fewer side-effects, and were more satisfied with their postoperative analgesia. Both groups showed an equally high degree of satisfaction with the new management pathway. Hospital stays, surgical outcomes, and frequency of complications were similar in the two groups. CONCLUSION. Continuous femoral nerve blockade proved to be a feasible and better alternative mode of postoperative analgesia than our conventional patient-controlled analgesia. Our new multidisciplinary management pathway and multimodal analgesic regimen featuring the continuous femoral nerve blockade appeared beneficial to patients and effective in our clinical setting.

Dietary consumption and diet diversity and risk of developing bladder cancer: results from the South and East China case-control study.

BACKGROUND: The epidemiologic evidence on the role of dietary consumption on the risk of bladder cancer in the Chinese population is limited. We investigated the role of dietary consumption and diet diversity on the risk of developing bladder cancer within a Chinese population. METHODS: A case-control study of 487 cases and 469 controls was conducted in four hospitals in China. A food frequency questionnaire was used to gather information on the consumption of 35 food items. Unconditional logistic regression models were used to derive odds ratios (ORs) and corresponding 95 % confidence intervals (95 % CI) for the relationship between dietary factors, dietary diversity scores, and bladder cancer. RESULTS: The ORs of bladder cancer for red meat (OR = 1.8, 95 % CI:1.1-3.0;p(trend) = 0.01), organ meat (OR = 1.6, 95 % CI:0.9-2.9;p(trend) = 0.04), leafy vegetables (OR = 2.9, 95 % CI:1.6-5.4;p trend = 0.003), bulb vegetables (OR = 2.3, 95 % CI:1.3-4.0;p(trend) = 0.003), and preserved vegetables (OR = 2.3, 95 % CI:1.2-4.2;p(trend) = 0.02) were significantly increased when comparing the highest to lowest level of consumption. The ORs for white fresh fish (OR = 0.5, 95 % CI:0.3-0.9;p(trend) = 0.004), citrus fruits (OR = 0.4, 95 % CI:0.3-0.8;p(trend) = 0.007), stone fruits (OR = 0.4, 95 % CI:0.2-0.6;p(trend) < 0.001), vine fruits (OR = 0.5, 95 % CI:0.2-1.0;p(trend) = 0.02), flower vegetables (OR = 0.3, 95 % CI:0.2-0.6;p(trend) < 0.001), potatoes (OR = 0.4, 95 % CI:0.2-0.9;p(trend) = 0.005), or dairy products (OR = 0.4, 95 % CI:0.3-0.7;p(trend) < 0.001) were significantly decreased when comparing the highest to lowest level of consumption. Subjects with the highest total diet diversity (OR = 0.4, 95 % CI:0.2-1.1;p(trend) = 0.02) and fruit diversity (OR = 0.1, 95 % CI:0.0-0.3;p(trend) < 0.001) had reduced ORs of and compared to subjects with the lowest diversity. CONCLUSION: Our results indicate that a diet with higher total diet diversity and in particular fruit diversity may reduce the risk of bladder cancer.

Angioplasty and stenting for intracranial atherosclerotic stenosis: position statement of the Hong Kong Society of Interventional and Therapeutic Neuroradiology.

As a means of preventing secondary ischaemic stroke, angioplasty and stenting are considered potentially beneficial for patients with severe intracranial atherosclerotic stenosis. However, the role of stenting has been challenged since the publication of the first randomised controlled trial on Stenting versus Aggressive Medical Management for Preventing Recurrent stroke in Intracranial arterial Stenosis (SAMMPRIS). This indicated that aggressive medical management was superior to stenting using Wingspan to prevent recurrent stroke, because stenting has a high peri-procedural stroke and death rate. In this paper, we review the management of intracranial atherosclerosis, revisit the skepticism on stenting, and state our position on the topic in the form of recommendations. These are based on the prevalence of the disease in Hong Kong, the high risk of recurrent stroke despite medical therapy in the presence of haemodynamic intracranial stenosis without sufficient collaterals, an analysis of the weak points of SAMMPRIS, and results of clinical studies in Hong Kong.

Fluid intake and the risk of bladder cancer: results from the South and East China case-control study on bladder cancer.

Although several studies have assessed the association between total fluid intake, specific drinks and bladder cancer, no firm conclusions can yet be drawn. Four hundred thirty two bladder cancer cases and 392 frequency matched hospital-based controls recruited in the South and East of China between October 2005 and June 2008 were interviewed on their intake of 6 nonalcoholic and 3 alcoholic drinks. Age, sex, smoking and hospital-adjusted odds ratios (OR) and 95 percent confidence intervals (95% CI) were calculated for all drinks and for total fluid intake using logistic regression. For 381 cases (81.9% men) and 371 controls (76.3% men), total fluid intake could be calculated. In men, an increase in total fluid intake was associated with a significantly decreased bladder cancer risk (OR 0.93, 95% CI: 0.88-0.99, per cup fluid consumed). Neither green nor black tea consumption was associated with bladder cancer. Daily consumption of milk significantly reduced the risk of bladder cancer by a half (OR 0.49, 95% CI: 0.32-0.76), which strengthens earlier suggestions that milk is probably associated with a decreased bladder cancer risk. Consumption of wine (OR 0.49, 95% CI: 0.34-0.70) and liquor/spirits (OR 0.65, 95% CI: 0.47-0.92) were associated with a significantly reduced risk. Consumption of water, fruit juice and beer appeared not associated with bladder cancer. There is no clear indication that the risks observed in this Chinese population are substantially different from those observed in Caucasian populations.

Prostate cancer cells modulate osteoblast mineralisation and osteoclast differentiation through Id-1.

BACKGROUND: Id-1 is overexpressed in and correlated with metastatic potential of prostate cancer. The role of Id-1 in this metastatic process was further analysed. METHODS: Conditioned media from prostate cancer cells, expressing various levels of Id-1, were used to stimulate pre-osteoclast differentiation and osteoblast mineralisation. Downstream effectors of Id-1 were identified. Expressions of Id-1 and its downstream effectors in prostate cancers were studied using immunohistochemistry in a prostate cancer patient cohort (N=110). RESULTS: We found that conditioned media from LNCaP prostate cancer cells overexpressing Id-1 had a higher ability to drive osteoclast differentiation and a lower ability to stimulate osteoblast mineralisation than control, whereas conditioned media from PC3 prostate cancer cells with Id-1 knockdown were less able to stimulate osteoclast differentiation. Id-1 was found to negatively regulate TNF-beta and this correlation was confirmed in human prostate cancer specimens (P=0.03). Furthermore, addition of recombinant TNF-beta to LNCaP Id-1 cell-derived media blocked the effect of Id-1 overexpression on osteoblast mineralisation. CONCLUSION: In prostate cancer cells, the ability of Id-1 to modulate bone cell differentiation favouring metastatic bone disease is partially mediated by TNF-beta, and Id-1 could be a potential therapeutic target for prostate cancer to bone metastasis.

Computed tomography in left-sided and right-sided blunt diaphragmatic rupture: experience with 43 patients.

AIM: To investigate differences in the radiographic signs for left and right-sided blunt diaphragmatic rupture (BDR) in order to provide guidance to avoid missing these injuries. MATERIALS AND METHODS: A retrospective review of the computed tomography (CT) examinations of 43 patients with BDR treated at our hospital between January 1995 and 2007 was undertaken. The presence of diaphragmatic discontinuity, diaphragmatic thickening, herniation of abdominal organs into the thoracic cavity, collar/hump sign, dependent viscera sign, abnormally elevated 4 cm or more above the dome of the other-sided hemi-diaphragm, and of associated injuries was recorded and their relationship to each other and to BDR diagnosis examined. A comparison between the use of axial and sagittal/coronal reconstruction images in diagnosis was also performed in 15 patients. RESULTS: On axial imaging, left-sided diaphragmatic rupture occurred in 31 patients (72%) and right-sided in 12 (28%). Twenty-nine patients had associated injuries. More than 60% of the patients showed the "dependent viscera" sign, "abdominal organ herniation" sign, diaphragm thickening, or had a more than 4 cm elevation of one side of the diaphragm. "Diaphragmatic discontinuity" and "stomach herniation" were seen almost exclusively in left-sided rupture. Those with BDR and haemothorax had a significantly lower incidence of "diaphragm discontinuity" (p=0.034) than those without haemothorax. Sagittal/coronal reconstruction slightly increased the number of band signs, diaphragmatic discontinuities and diaphragmatic thickenings seen. CONCLUSIONS: Of the CT signs examined in this study, when herniation of abdominal organs was used as a diagnostic marker, only a very small fraction of trauma patients identifiable by CT would be missed. Further, CT signs differ for left-sided and right-sided BDR, thus the possibility of BDR should be considered when any of the reported CT signs are present.