Effects of enhanced recovery after surgery practices on postoperative recovery and length of stay after unilateral primary total hip or knee arthroplasty in a private hospital.

INTRODUCTION: Enhanced recovery after surgery (ERAS) practices improve postoperative recovery and reduce postoperative length of stay (LOS) in patients undergoing primary total hip arthroplasty (THA) or total knee arthroplasty (TKA). Our study investigated whether these promising results could be reproduced in a private hospital setting. METHODS: In total, 228 patients were included in the study cohort: the conventional group comprised 117 patients from 2012 to 2014, while the ERAS group comprised 111 patients from 2017 to 2018. All patients had undergone unilateral primary THA or TKA at a private hospital in Hong Kong. The outcome was postoperative LOS; factors affecting LOS were also investigated. RESULTS: No significant differences were found in any baseline parameters between the two groups of patients. The mean LOS was significantly shorter in the ERAS group than in the conventional group (3.28 ± 1.04 vs 5.16 ± 2.06 days, P<0.001). Moreover, a significantly greater proportion of patients could be discharged on or before postoperative day 3 in the ERAS group, compared with the conventional group (77.5% vs 13.7%, P<0.001). A significant difference in LOS was observed between general ward and private ward patients (3.06 ± 0.59 vs 3.66 ± 1.46 days, P=0.003). Sex, age, and nature of surgery (TKA vs THA) did not have significant effects on LOS. CONCLUSIONS: The ERAS practices yielded a significant improvement in postoperative LOS, compared to conventional practices, among patients who underwent unilateral primary THA or TKA in a private hospital.

Bacteriology and risk factors associated with periprosthetic joint infection after primary total knee arthroplasty: retrospective study of 2543 cases.

INTRODUCTION: Periprosthetic joint infection after total knee arthroplasty is a serious complication. This study aimed to identify risk factors and bacteriological features associated with periprosthetic joint infection after primary total knee arthroplasty performed at a teaching hospital. METHODS: We reviewed 2543 elective primary total knee arthroplasties performed at our institution from 1993 to 2013. Data were collected from the Hong Kong Hospital Authority's Clinical Data Analysis and Reporting System, the Infection Control Team, and the joint replacement division registry. The association between potential risk factors and periprosthetic joint infection was examined by univariable analysis and multivariable logistic regression. Univariable analyses were also performed to examine the association between potential risk factors and bacteriology and between potential risk factors, including bacteriology, and early-onset infection. RESULTS: The incidence of periprosthetic joint infection in our series was 1.34% (n=34). The incidence of early-onset infection was 0.39% (n=24). Of the periprosthetic joint infections, 29.4% were early-onset infections. In both univariable and multivariable analyses, only rheumatoid arthritis was a significant predictor of periprosthetic joint infection. Methicillin-sensitive Staphylococcus aureus was the most common causative organism. We did not identify any significant association between potential risk factors and bacteriology. Periprosthetic joint infection caused by skin flora was positively associated with early-onset infection but the association was not statistically significant. CONCLUSION: The incidence of periprosthetic joint infection after elective primary total knee arthroplasty performed at our institution from 1993 to 2013 was 1.34%. Rheumatoid arthritis was a significant risk factor for periprosthetic joint infection.

Why do Hong Kong patients need total hip arthroplasty? An analysis of 512 hips from 1998 to 2010.

INTRODUCTION: The number of patients undergoing total hip replacement surgeries has increased as a result of a rise in the ageing population. This study reviewed the demographics and disease spectrum leading to primary total hip replacement in the Chinese population from 1998 to 2010. METHODS: This case series was conducted in a university teaching hospital in Hong Kong. Data from the prospective joint registry of all patients who underwent primary total hip replacement from January 1998 to December 2010 were reviewed. Patients' age and sex, diagnosis, as well as the Harris Hip Scores before operation and at the last follow-up were described. RESULTS: There were 512 primary total hip replacements performed on 419 patients (43.4% males) during the study period. All had clinical follow-up for at least 2 years. The mean age of the patients was 57.6 (standard deviation, 16.6) years. In males, the main aetiology was osteonecrosis (50.9%), ankylosing spondylitis (19.5%), and post-traumatic arthritis (8.5%). For females, it was osteonecrosis (33.0%), primary osteoarthritis (18.8%), and post-traumatic arthritis (15.8%). Alcohol-induced (52.5%) and idiopathic (40.7%) was the most common cause of osteonecrosis in males and females, respectively. The mean preoperative Harris Hip Score and that at last follow-up was 43.9 (standard deviation, 18.3) and 89.7 (standard deviation, 13.0), respectively. CONCLUSIONS: Osteonecrosis was the most common aetiology leading to total hip replacement although there were different causes in both sexes leading to it. The clinical result in terms of Harris Hip Score was good for all patients who required total hip replacement.

Bony ankylosis of the knee secondary to heterotopic ossification after total knee arthroplasty: a case report.

We report a case of bony ankylosis of the knee secondary to severe and extensive heterotopic ossification over 9 years after primary total knee arthroplasty in a 71-year-old woman.

Review article: Venous thromboembolism after total joint replacement.

Venous thromboembolism can occur in up to 84% of cases following total joint replacement. It can result in pain, swelling, chronic post-thrombotic syndrome, and pulmonary embolism. Its prevention is vital to the success of the surgery. To achieve a safe and effective prophylaxis, a combination of mechanical and pharmacologic agents should be used. New generation of thromboprophylactic agents target different factors of the coagulation pathway.

Perioperative antithrombotic management in joint replacement surgeries.

OBJECTIVES: To determine optimal perioperative antithrombotic management for patients with cardiac diseases undergoing joint replacement surgeries. DATA SOURCES: MEDLINE and PubMed database search up to January 2013. STUDY SELECTION: Those dealing with perioperative antithrombotic management of patients undergoing orthopaedic operations, especially joint replacement, and also those undergoing general surgery. Various combinations of the following key words were used in our search: "antiplatelet", "antithrombotic", "anticoagulant", "coronary stent", "perioperative", "venous thromboembolism", "cardiovascular", "surgery", "orthopaedic", "knee replacement", "hip replacement", "joint replacement", and "arthroplasty". DATA EXTRACTION: Literature review, original articles, and best practice guidelines. DATA SYNTHESIS: Patients should be stratified according to their risk of developing arterial thromboembolism in order to decide the most appropriate perioperative antiplatelet or anticoagulant regimen for them. After recent coronary stenting, including bare-metal stents implanted within 6 weeks and drug-eluting stents implanted within 6 months, surgery should be deferred. For venous thromboembolism prophylaxis in patients already on aspirin, the dosage should be adjusted as necessary or additional low-molecular-weight heparin administered. CONCLUSION: The perioperative management of patients with cardiac diseases in receipt of antithrombotic agents is based upon a delicate balance between the perceived risk of arterial thromboembolism and the perceived risk of perioperative bleeding. One must exercise good judgement in deciding the most appropriate perioperative antithrombotic regimen. Venous thromboembolism is also a common problem after joint replacement surgeries. For patients already on aspirin, optimal venous thromboembolism prophylaxis is still being debated.

Review article: Joint aspiration for diagnosis of periprosthetic infection.

Joint aspiration is a reliable tool for diagnosis of periprosthetic infection. There are different indications, techniques, and approaches for joint aspiration. We recommend that it be performed selectively when infection is suspected clinically. The specimens should be interpreted based on the results of the culture as well as the white cell count and differential. Specimen collection, transport, and analysis should be prompt to ensure yield accuracy.

Distal femur rotation relates to joint obliquity in ACL-deficient Chinese.

BACKGROUND: The lower limb osteometry of Chinese differs from that of whites. The joint line of the knee in the coronal plane in Chinese is more medially inclined and the posterior condylar angle of the distal femur in the axial plane is larger. However, it is unclear whether there is any direct association between the coronal plane and axial plane osteometry. QUESTIONS/PURPOSES: We asked whether the joint line obliquity of the knee is related to the posterior condylar angle of the distal femur in young Chinese subjects. METHODS: Ninety-nine young Chinese patients with anterior cruciate ligament injuries were recruited. The lower limb alignment and joint line obliquity were measured using standing long radiographs of the whole lower limb. The rotational alignment of the distal femur was assessed in the axial cuts of the MRI. RESULTS: The distal femur rotational alignment was associated with the obliquity of the knee in Chinese. The posterior condylar angle was 5° ± 2°. The knee was 5° ± 3° medially inclined. CONCLUSIONS: The joint line of the knee in a group of young Chinese patients was more medially inclined than that of whites. The posterior condylar angle of the distal femur was larger. The presence of an association between distal femur rotational alignment and joint line obliquity in this group of young Chinese patients suggests a possible developmental cause explaining the difference in osteometry between races.

Total knee arthroplasty for primary knee osteoarthritis: changing pattern over the past 10 years.

OBJECTIVE: To review the epidemiology of total knee arthroplasty for primary osteoarthritis and the change of patient characteristics over the last decade. DESIGN: Retrospective review. SETTING: A tertiary referral centre for joint replacement surgery in a teaching hospital in Hong Kong. PATIENTS: All patients who underwent primary total knee arthroplasty for primary knee osteoarthritis from January 2000 to December 2009. RESULTS: In all, 1157 total knee arthroplasties (589 left and 568 right) were performed on 588 females and 162 males. The annual number of total knee arthroplasties increased from 91 in 2000 to 181 in 2009. The annual number of patients increased from 58 (46 female, 12 male) in 2000 to 159 (117 female, 42 male) in 2009. When compared yearly results, there were no significant changes in the preoperative Knee Society Knee Score, Knee Society Functional Assessment, and passive range of motion of these patients. However, there was a significant decreasing trend with regard to lower limb mechanical axis mal-alignment, from 15.1° deviation from the neutral axis in 2000, to 14.8° deviation in 2004, and then 12.9° deviation in 2009 (mostly varus deformity). There was no difference between left knees and right knees, and between females and males. The mean age of the patients did not show significant change over the past decade, but the number and proportion of patients over 80 years old showed an increase from 4.8% (2000 to 2004) to 13.8% (2005 to 2009). On the other hand, the number and proportion of patients under the age of 60 years did not change. CONCLUSIONS: There was an increasing trend towards total knee arthroplasties, both in terms of number of operations and patients. The number of younger patients having total knee arthroplasty did not increase over the last 10 years, whereas the number of those older than 80 years increased significantly over that period.

Antibiotic prophylaxis after total joint replacements.

OBJECTIVES: To review the latest evidence on antibiotic prophylaxis for patients with total joint replacements to prevent prosthesis infections. DATA SOURCES: Literature search of Medline and PubMed until June 2009. STUDY SELECTION: Studies of patients with total joint replacements from around the world, studies concerning antibiotic prophylaxis, as well as chemoprophylaxis guidelines from orthopaedic associations were searched. DATA EXTRACTION: Literature review, original articles, case reports, best practice guidelines. DATA SYNTHESIS: With the rising incidence of patients with total joint replacements, subsequent deep infection of the implants is a rare but dreaded complication which has immense physiological, psychological, financial, and social implications. Guidelines from urologists, gastroenterologists, and dental surgeons attempt to identify high-risk patients who may be more susceptible to prosthetic joint infections. These patients are provided with prophylactic antibiotics before any invasive procedure that may cause bacterial seeding to prosthetic joints. Most orthopaedic associations around the world adopt a similar policy to provide prophylaxis to cover any anticipated chance of bacteraemia. The American Association of Orthopaedic Surgeons adopts the most cautious approach in which all patients with total joint replacements who undergo any procedure that breaches a mucosal surface receive prophylactic antibiotics. CONCLUSION: The guidelines from the American Association of Orthopaedic Surgeons seem to have an all-encompassing policy when it comes to providing prophylactic antibiotics. Nonetheless, physicians must still exercise their judgement and customise the treatment to each patient. The benefits of prophylactic antibiotics must be balanced against the risks of drug side-effects and the emergence of antibiotic resistance.

Cytological distinction between high-risk and low-risk human papillomavirus infections in SurePath liquid-based cell preparations.

AIMS: To investigate the correlation of various diagnostic cytological features in SurePath liquid-based cell preparations with high-risk human papillomavirus (HPV) infection. METHODS: Case-control study. SurePath specimens from 510 cases that had been tested for HPV DNA by Hybrid Capture 2 assay were retrieved and re-examined for 10 cytological features. Distribution of these features in high- and low-risk HPV types was compared and risk statistics were estimated. Effects of cervicitis on the manifestation of HPV cytological changes were adjusted by means of logistic regression. RESULTS: Cytological features of nuclear hyperchromasia, multinucleation and atypical metaplastic cells were predominantly noted in high-risk HPV infection in the category of atypical squamous cells of undetermined significance/low-grade squamous intraepithelial lesion. The odds ratios of these three features were 6-12 times higher in high-risk than low-risk HPV infection. CONCLUSIONS: Some diagnostic cytological features can be used as markers in Pap smear screening for assessing the types of HPV infection.

Comparison of range of motion after standard and high-flexion posterior stabilised total knee replacement.

The purpose of this study was to compare the range of motion after standard version posterior stabilised TKR and high-flexion version TKR in patients receiving bilateral total knee replacement. Thirty-five patients were recruited. The range of motion of the knees was measured clinically with a goniometer in both the pre-operative period and the most recent follow-up. It was found that the pre-operative range of motion was comparable in the two groups. The average post-operative flexion was 105 degrees +/- 13 degrees in the standard version group and 106 degrees +/- 14 degrees in the high-flexion design group (p = 0.201, paired t-test; beta error = 0.073). A slight loss in flexion was observed in the standard version group (0.5 degrees ) as opposed to a slight gain in the high-flexion design group (2 degrees ). However, this was not statistically significant (p = 0.251, paired t-test; beta error = 0.105).

Cementless acetabular component inserted without screws - the effect of immediate weight-bearing.

Seventy-four total hip arthroplasties using a cementless acetabular component without holes for supplemental screw fixation were evaluated during a follow-up period of 2-6 years. Immediate full weight-bearing walking was allowed after the operation. A comparison of anteroposterior (AP) radiographs of the pelvis taken in the early postoperative period and when the patient returned for the final follow-up revealed that there was no migration of the acetabular component. Based on the early postoperative radiographs and using the zones described by Martell et al. [J Bone Joint Surg (1993) 75-A:554-571], gaps between the acetabular component and the bone occurred at zone A2 in three hips (4.1%), at zone B1 in 12 hips (16.2%), and at zone B2 in seven hips (9.5%). The final follow-up radiographs, however, revealed only one hip to have a gap of 1.1 mm at zone B2; the majority of the gaps had disappeared. The results suggest that immediate weight-bearing walking did not result in the migration of the cementless acetabular component.

Extensively coated femoral components in revision hip arthroplasty: follow-up study of 23 patients.

PURPOSE: To review the outcome of revision hip arthroplasty using extensively coated femoral components. METHODS: We reviewed the results of revision involving 24 extensively porous-coated cementless femoral components in 23 patients, whose mean age was 52.4 years (range, 28.0-79.0 years). Most revisions were performed for aseptic loosening of the previously cemented femoral component. All patients were followed up for a minimum period of 24.0 months (mean, 61.1 months). RESULTS: Of the 24 femoral stems, 20 showed bone ingrowth, 3 showed stable fibrous ingrowth, and one was unstable because of deep infection. Intra-operative anterior femoral diaphyseal perforation occurred in 2 hips during the insertion of straight femoral components of 200 mm. Postoperative radiographs displayed marked cortical erosion in 3 other hips and cortical perforation in one. CONCLUSION: The results from the use of extensively coated femoral components were promising. Nevertheless, anterior cortical perforations were also common, which may be related to more bowing of the femora among the Chinese patients. Caution must be exercised when inserting a long, straight, extensively coated femoral component.

Six month radiological and physiological outcomes in severe acute respiratory syndrome (SARS) survivors.

BACKGROUND: The long term physiological and radiological outcomes of SARS survivors and their possible determinants are uncertain. METHODS: SARS survivors in a follow up clinic in a regional hospital underwent high resolution computed tomography (HRCT) of the thorax and lung function tests 6 months after admission to hospital. The associations between the clinical and demographic data of the patients and the physiological and radiological outcomes were examined. RESULTS: Fifty seven patients took part in the study. Lung function abnormalities were detected in 43 patients (75.4%), with restrictive defects (n = 16) being most common (28.1%). Radiological abnormalities of any degree were detected in 43 patients (75.4%). Only the use of pulse corticosteroids was associated with the presence of CT abnormalities (p = 0.043, OR 6.65, 95% CI 1.06 to 41.73). CONCLUSIONS: Physiological and radiological abnormalities are still present in a considerable proportion of SARS survivors at 6 months.

Parent training: experience of the New Territories West School Health Promotion Project of Hong Kong.

Parents' participation in school life is an important element of a health-promoting school. To maximize the potential of parents as partners in health education and take on a leading role in promoting health in the school, family and community, a parental health education programme using the empowerment model had been launched in partnership between academic and health sectors. A total of 28 parents selected from eight schools in the New Territories West region of Hong Kong participated in the programme. Evaluation of the programme revealed that the programme had matched well with the expectation of most participants. All respondents had reported an increase in health awareness and knowledge, and confidence to promote health concepts in familiar environments, such as the home and school. They also showed interest to participate in further training in health related issues. Parental health education is recommended to enhance active involvement for building a greater sense of belonging and to put through individual empowerment to community empowerment. Parental involvement in school health promotion would be an effective way to facilitate the paradigm shift.