Prevalence and changes in analgesic medication utilisation 1 year prior to total joint replacement in an older cohort of patients.

OBJECTIVES: To evaluate the prevalence and change in analgesic medications use prior to joint replacement in older patients between 2001 and 2012. METHODS: A population based epidemiological study was conducted. Opioids, non-steroidal anti-inflammatories (NSAIDs), paracetamol, corticosteroid injections, medications for neuropathic pain, hypnotics, and muscle relaxants supplied 1 year prior to total knee replacement (TKR, n = 15,517) and hip replacement (THR, n = 10,018) were assessed. Patient characteristics and surgical indication adjusted prevalence ratios (PRs) and 95% confidence intervals (CI) are provided. RESULTS: From 2001 to 2012, in the TKR cohort (median age 78.9) the prevalence of opioid use prior to surgery increased from 37% to 49% (PR = 1.01, 95% CI 1.00-1.01, P = 0.01), while in the THR cohort (median age 81.1) it increased from 44% to 54% (PR = 1.01, 95% CI 1.01-1.02, P < 0.001). Paracetamol use increased from 52% to 61% (PR = 1.0, 95% CI 1.0-1.0, P = 0.913) in the TKR cohort and from 55% to 67% (PR = 1.01, 95% CI 1.00-1.01, P = 0.005) in the THR cohort. Neuropathic pain medication use increased from 5% to 11% in the TKR cohort (PR = 1.04, 95% CI 1.02-1.06, P < 0.0001) and from 6% to 12% in the THR cohort (PR = 1.06, 95% CI 1.04-1.09, P < 0.0001). NSAID use decreased from 76% to 50% in the TKR cohort (PR = 0.96, 95% CI 0.95-0.96, P < 0.0001), and from 81% to 47% in THR cohort (PR = 0.95, 95% CI 0.94-0.95, P < 0.0001). Corticosteroid injections prevalence also decreased (TKR: 21-18%, PR = 0.97, 95% CI 0.96-0.97, P < 0.001, THR: 18-17%, PR = 0.97, 95% CI 0.96-0.98, P < 0.001). CONCLUSION: Pain medication utilization prior to joint replacement surgery changed significantly in this national older cohort of patients during the 2000s.

Projected increase in total knee arthroplasty in the United States - an alternative projection model.

OBJECTIVE: The purpose of our study was to estimate the future incidence rate (IR) and volume of primary total knee arthroplasty (TKA) in the United States from 2015 to 2050 using a conservative projection model that assumes a maximum IR of procedures. Furthermore, our study compared these projections to a model assuming exponential growth, as done in previous studies, for illustrative purposes. METHODS: A population based epidemiological study was conducted using data from US National Inpatient Sample (NIS) and Census Bureau. Primary TKA procedures performed between 1993 and 2012 were identified. The IR, 95% confidence intervals (CI), or prediction intervals (PI) of TKA per 100,000 US citizens over the age of 40 years were calculated. The estimated IR was used as the outcome of a regression modelling with a logistic regression (i.e., conservative model) and Poisson regression equation (i.e., exponential growth model). RESULTS: Logistic regression modelling suggests the IR of TKA is expected to increase 69% by 2050 compared to 2012, from 429 (95%CI 374-453) procedures/100,000 in 2012 to 725 (95%PI 121-1041) in 2050. This translates into a 143% projected increase in TKA volume. Using the Poisson model, the IR in 2050 was projected to increase 565%, to 2854 (95%CI 2278-4004) procedures/100,000 IR, which is an 855% projected increase in volume compared to 2012. CONCLUSIONS: Even after using a conservative projection approach, the number of TKAs in the US, which already has the highest IR of knee arthroplasty in the world, is expected to increase 143% by 2050.

Evaluation of three co-morbidity measures to predict mortality in patients undergoing total joint arthroplasty.

OBJECTIVE: To evaluate the 90 days and 1 year mortality predictive ability of the RxRisk-V, Charlson, and Elixhauser co-morbidity measures in total hip arthroplasty (THA) and total knee arthroplasty (TKA) patients. METHOD: A retrospective study of 11,848 THAs and 18,972 TKAs (2001-2002) was conducted. Death within 90 days and 1 year of the surgery were the main endpoints. Co-morbidity measures were calculated using either medication or hospitalisation history. Logistic regression models were employed and discrimination and calibration were assessed. Specifically, models with unweighted and weighted measure scores, models with the specific conditions, and a model combining conditions identified by all measures were assessed. RESULTS: In THAs, the best performing prediction models included co-morbidities from all three measures (90 days: c = 0.84, P = 0.284, 1 year: c = 0.79, P = 0.158). Individually, the model with Charlson conditions performed best at 90 days mortality (c = 0.80, P = 0.777) and the Charlson and Elixhauser performed similarly at 1 year (both c = 0.77, P > 0.05). In TKAs, the best performing prediction model included co-morbidities from all measures (90 days: c = 0.82, P = 0.349, 1 year: c = 0.78, P = 0.873). Individually, the model with Elixhauser conditions performed best with 90 days mortality (c = 0.79, P = 0.435) and all performed similarly at 1 year (c = 0.74-0.75, all P > 0.05). CONCLUSIONS: A combined model with co-morbidities identified by the Elixhauser, Charlson, and RxRisk-V was the best mortality prediction model. The RxRisk-V did not perform as well as the others. Because of the Elixhauser and Charlson's similar performance we suggest basing the choice of measurement use on factors such as the need of specific conditions and modelling limitations.

Prolonged Wait Time Prior to Entry to Home Care Packages Increases the Risk of Mortality and Transition to Permanent Residential Aged Care Services: Findings from the Registry of Older South Australians (ROSA).

BACKGROUND: Older Australians prefer to live in their own homes for longer and reforms have attempted to increase the volume of home care packages (HCPs) accordingly but there remains a queue with the longer-term consequences unclear. OBJECTIVES: This study aims to characterise older Australians according to their wait times for a home care package (HCP), evaluate the association between wait time and mortality and evaluate the association between wait time and transition to permanent residential aged care services after HCP. DESIGN: A retrospective cohort study using data from the National Historical cohort (2003-2014) of the Registry of Older South Australians (ROSA) was conducted. SETTING: Home based aged care services, national cohort. METHODS: Wait time was estimated from approval date to date of receiving a HCP. Descriptive, survival estimates (95% confidence intervals (CIs)), and multivariable survival analyses (Cox-regression) were conducted to evaluate the risk of mortality and transition to permanent residential aged care services by quartiles of wait time for HCP. RESULTS: The cohort was followed for 4.0 years (interquartile range IQR (1.8-7.2)) and 38% were alive at the end of the study period with a median wait time for HCP of 62 (21-187) days. From 178,924 older people who received a HCP during the study period (2003-2013), 33.2% people received HCP within 30 days, 74.3% within 6 months and 25.7% after 6 months. The effect of wait time on risk of mortality was time-dependent, with longer wait times associated with higher mortality in the longer term. Compared to people who waited ≤30 days for a HCP, individuals who waited more than 6 months had an almost 20% excess risk of death (adjusted hazard ratio (aHR), 95%CI = (1.18, 1.16-1.21)) 2 years after entry into a HCP. Those who waited more than 6 months also had a 10% (1.10, 1.06-1.13) higher risk of transition to permanent residential aged care services after two years. CONCLUSION: Prolonged wait times for HCP is associated with a higher risk of long-term mortality as well as transition to permanent residential aged care. It remains to be seen if a shortening of this wait time translates into better health outcomes.

Gastric disorders of cattle in western Rio Grande do Sul State, Brazil / Distúrbios gástricos de bovinos no Oeste do Rio Grande do Sul

A retrospective study of gastric disorders in autopsied cattle in the Western region of Rio Grande do Sul State, was performed. The exam reports of bovine necropsy of the Veterinary Pathology Laboratory, Unipampa, were analyzed in the period from 2010 to 2018. All cases in which death was primarily caused by disturbance in the gastric chambers were included. During the period evaluated, 141 cattle were necropsied. Of those, 25 had gastric disorders. Of those, 53% had alterations in the rumen, followed by abomasum (17%), involvement of two chambers (13%) and reticulum (9%). Most cases corresponded to beef cattle raised in an extensive system and most them for calf production and fattening with an average age of approximately three years. The cases occurred in farms of four different municipalities. Bullous bloat by excessive Trifolium repens ingestion was the gastric disturbance with the highest number of dead cattle observed in this study, especially in irrigated áreas of livestock farms. Cases such as lactic acidosis, ruminal alkalosis due to excessive urea ingestion and Baccharis coridifolia poisoning were also important gastric disturbances in necropsied cattle, associated especially with poor management and period of scarcity of good quality fodder. Cases of Clostridium perfringens infection were also observed in young cattle suggesting that it is an important infectious agent in the evaluated cattle herds, also showing failures in vaccination of the herds. As observed, gastric disturbances in cattle in the western region of Rio Grande do Sul have several causes. Metabolic/toxic and infectious disturbances were important causes of mortality in the herds, inducing considerable economic losses. Based on this study, it is clear that the majority of outbreaks or isolated cases occurred due to errors in the management of the properties and the vast majority of them could have been avoided with improvements in the technical qualification of the workers and simple adjustments in the farming methods. It is also emphasized the importance of the conclusive diagnosis to control these disorders, once after the orientation to the producers, was observed significant decrease in cattle losses in the farms.(AU)

Foi realizado estudo retrospectivo dos distúrbios gástricos em bovinos necropsiados na região Oeste do Rio Grande do Sul. Foram analisados os relatórios de exame de necropsia de bovinos do Laboratório de Patologia Veterinária (LPV) da Universidade Federal do Pampa (Unipampa), Rio Grande do Sul, no período de 2010 a 2018. Foram incluídos todos os casos nos quais a morte foi causada primariamente pelo distúrbio nas câmaras gástricas. De um total de 141 bovinos necropsiados, 25 corresponderam a distúrbios gástricos. Dentre esses, 53% apresentaram alterações no rúmen, seguido de abomaso 17%, acometimento concomitante de duas câmaras 13% e retículo 9%. A maioria dos casos ocorreram em bovinos de corte criados em sistema extensivo e a maioria destinados à produção de bezerros e engorda com média de idade de aproximadamente três anos. Os casos ocorreram em propriedades rurais de quatro municípios da região Oeste do estado. O timpanismo bolhoso por ingestão excessiva de Trifolium repens foi o distúrbio gástrico com maior número de bovinos mortos observados nesse estudo, especialmente em propriedades com criação de animais em áreas de irrigação. Casos como acidose láctica, alcalose ruminal por intoxicação por ureia e intoxicação por Baccharis coridifolia também foram importantes distúrbios gástricos nos bovinos necropsiados e percebeu-se sua associação a falhas no manejo e à época de escassez de forragem de boa qualidade. Foram observados ainda casos de infecção por Clostridium perfringens em bovinos jovens o que sugere também tratar-se de um importante agente infeccioso nos rebanhos bovinos avaliados, demonstrando ainda falhas na vacinação dos rebanhos. Conforme observado, diversos são os distúrbios gástricos em bovinos na região Oeste do Rio Grande do Sul, tendo como importantes causas de mortalidades os distúrbios metabólicos/tóxicos e infecciosos, induzindo consideráveis perdas econômicas. Com base nesse levantamento, percebe-se que a maioria dos surtos ou casos isolados estudados ocorreram por erros no manejo nas propriedades e, na sua grande maioria, poderiam ter sido evitados com especialização da mão de obra e ajustes simples. Ressalta-se ainda a importância do diagnóstico conclusivo para controle desses distúrbios, uma vez que, após a orientação aos produtores, observou-se significativa diminuição das perdas de bovinos nas propriedades.(AU)

Increased risk of revision for high flexion total knee replacement with thicker tibial liners.

The outcome of total knee replacement (TKR) using components designed to increase the range of flexion is not fully understood. The short- to mid-term risk of aseptic revision in high flexion TKR was evaluated. The endpoint of the study was aseptic revision and the following variables were investigated: implant design (high flexion vs non-high flexion), the thickness of the tibial insert (≤ 14 mm vs > 14 mm), cruciate ligament (posterior stabilised (PS) vs cruciate retaining), mobility (fixed vs rotating), and the manufacturer (Zimmer, Smith & Nephew and DePuy). Covariates included patient, implant, surgeon and hospital factors. Marginal Cox proportional hazard models were used. In a cohort of 64 000 TKRs, high flexion components were used in 8035 (12.5%). The high flexion knees with tibial liners of thickness > 14 mm had a density of revision of 1.45/100 years of observation, compared with 0.37/100 in non-high flexion TKR with liners ≤ 14 mm thick. Relative to a standard fixed PS TKR, the NexGen (Zimmer, Warsaw, Indiana) Gender Specific Female high flexion fixed PS TKR had an increased risk of revision (hazard ratio (HR) 2.27 (95% confidence interval (CI) 1.48 to 3.50)), an effect that was magnified when a thicker tibial insert was used (HR 8.10 (95% CI 4.41 to 14.89)). Surgeons should be cautious when choosing high flexion TKRs, particularly when thicker tibial liners might be required.

The risk of surgical site infection and re-admission in obese patients undergoing total joint replacement who lose weight before surgery and keep it off post-operatively.

This study evaluated whether obese patients who lost weight before their total joint replacement and kept it off post-operatively were at lower risk of surgical site infection (SSI) and re-admission compared with those who remained the same weight. We reviewed 444 patients who underwent a total hip replacement and 937 with a total knee replacement who lost weight pre-operatively and sustained their weight loss after surgery. After adjustments, patients who lost weight before a total hip replacement and kept it off post-operatively had a 3.77 (95% confidence interval (CI) 1.59 to 8.95) greater likelihood of deep SSIs and those who lost weight before a total knee replacement had a 1.63 (95% CI 1.16 to 2.28) greater likelihood of re-admission compared with the reference group. These findings raise questions about the safety of weight management before total replacement of the hip and knee joints.

Reconstruction of the anterior cruciate ligament: association of graft choice with increased risk of early revision.

We examined the association of graft type with the risk of early revision of primary anterior cruciate ligament reconstruction (ACLR) in a community-based sample. A retrospective analysis of a cohort of 9817 ACLRs recorded in an ACLR Registry was performed. Patients were included if they underwent primary ACLR with bone-patellar tendon-bone autograft, hamstring tendon autograft or allograft tissue. Aseptic failure was the main endpoint of the study. After adjusting for age, gender, ethnicity, and body mass index, allografts had a 3.02 times (95% confidence interval (CI) 1.93 to 4.72) higher risk of aseptic revision than bone-patellar tendon-bone autografts (p < 0.001). Hamstring tendon autografts had a 1.82 times (95% CI 1.10 to 3.00) higher risk of revision compared with bone-patellar tendon-bone autografts (p = 0.019). For each year increase in age, the risk of revision decreased by 7% (95% CI 5 to 9). In gender-specific analyses a 2.26 times (95% CI 1.15 to 4.44) increased risk of hamstring tendon autograft revision in females was observed compared with bone-patellar tendon-bone autograft. We conclude that allograft tissue, hamstring tendon autografts, and younger age may all increase the risk of early revision surgery after ACLR.

Risk factors associated with surgical site infection in 30,491 primary total hip replacements.

We examined patient and surgical factors associated with deep surgical site infection (SSI) following total hip replacement (THR) in a large integrated healthcare system. A retrospective review of a cohort of primary THRs performed between 2001 and 2009 was conducted. Patient characteristics, surgical details, surgeon and hospital volumes, and SSIs were identified using the Kaiser Permanente Total Joint Replacement Registry (TJRR). Proportional-hazard regression models were used to assess risk factors for SSI. The study cohort consisted of 30,491 THRs, of which 17,474 (57%) were performed on women. The mean age of the patients in the whole series was 65.5 years (13 to 97; SD 11.8) and the mean body mass index was 29.3 kg/m(2) (15 to 67; SD 5.9). The incidence of SSI was 0.51% (155 of 30,491). Patient factors associated with SSI included female gender, obesity, and American Society of Anesthesiologists (ASA) score ≥ 3. Age, diagnosis, diabetes and race were not associated with SSI. The only surgical factor associated with SSI was a bilateral procedure. Surgeon and hospital volumes, use of antibiotic-laden cement, fixation method, laminar flow, body exhaust suits, surgical approach and fellowship training were not associated with risk of SSI. A comprehensive infection surveillance system, combined with a TJRR, identified patient and surgical factors associated with SSI. Obesity and chronic medical conditions should be addressed prior to THR. The finding of increased SSI risk with bilateral THR requires further investigation.