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.

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.