Aims. The aim of this study was to report the meaningful values of the EuroQol five-dimension three-level questionnaire (EQ-5D-3L) and EuroQol visual analogue scale (EQ-VAS) in patients undergoing primary knee arthroplasty (KA). Methods. This is a retrospective study of patients undergoing primary KA for osteoarthritis in a university teaching hospital (Royal Infirmary of Edinburgh) (1 January 2013 to 31 December 2019). Pre- and postoperative (one-year) data were prospectively collected for 3,181 patients (median age 69.9 years (interquartile range (IQR) 64.2 to 76.1); females, n = 1,745 (54.9%); median BMI 30.1 kg/m. 2. (IQR 26.6 to 34.2)). The reliability of the EQ-5D-3L was measured using Cronbach’s alpha. Responsiveness was determined by calculating the anchor-based minimal clinically important difference (MCID), the minimal important change (MIC) (cohort and individual), the patient-acceptable symptom state (PASS) predictive of satisfaction, and the minimal detectable change at 90% confidence intervals (MDC-90). Results. The EQ-5D-3L demonstrated good internal consistency with an overall Cronbach alpha of 0.75 (preoperative) and 0.88 (postoperative), respectively. The MCID for the Index score was 0.085 (95% confidence interval (CI) 0.042 to 0.127) and EQ-VAS was 6.41 (95% CI 3.497 to 9.323). The MIC. COHORT. was 0.289 for the EQ-5D and 5.27 for the EQ-VAS. However, the MIC. INDIVIDUAL. for both the EQ-5D-3L Index (0.105) and EQ-VAS (-1) demonstrated poor-to-acceptable reliability. The MDC-90 was 0.023 for the EQ-5D-3L Index and 1.0 for the EQ-VAS. The PASS for the postoperative EQ-5D-3L Index and EQ-VAS scores predictive of patient satisfaction were 0.708 and 77.0, respectively. Conclusion. The meaningful values of the EQ-5D-3L Index and EQ-VAS scores can be used to measure clinically relevant changes in health-related quality of life in patients undergoing primary KA. Cite this article: Bone Joint Res 2022;11(9):619–628

Aims. We compared the risks of re-revision and mortality between two-stage revision surgery and single-stage revision surgery among patients with infected primary knee arthroplasty. Methods. Patients with a periprosthetic joint infection (PJI) of their primary knee arthroplasty, initially revised with a single-stage or a two-stage procedure in England and Wales between 2003 and 2014, were identified from the National Joint Registry. We used Poisson regression with restricted cubic splines to compute hazard ratios (HR) at different postoperative periods. The total number of revisions and re-revisions undergone by patients was compared between the two strategies. Results. A total of 489 primary knee arthroplasties were revised with single-stage procedure (1,390 person-years) and 2,377 with two-stage procedure (8,349 person-years). The adjusted incidence rates of all-cause re-revision and for infection were comparable between these strategies (HR overall five years, 1.15 (95% confidence interval (CI) 0.87 to 1.52), p = 0.308; HR overall five years, 0.99 (95% CI 0.70 to 1.39), p = 0.949, respectively). Patients initially managed with single-stage revision received fewer revision procedures overall than after two-stage revision (1.2 vs 2.2, p < 0.001). Mortality was lower for single-stage revision between six and 18 months postoperative (HR at six months, 0.51 (95% CI 0.25 to 1.00), p = 0.049 HR at 18 months, 0.33 (95% CI 0.12 to 0.99), p = 0.048) and comparable at other timepoints. Conclusion. The risk of re-revision was similar between single- and two-stage revision for infected primary knee arthroplasty. Single-stage group required fewer revisions overall, with lower or comparable mortality at specific postoperative periods. The single-stage revision is a safe and effective strategy to treat infected knee arthroplasties. There is potential for increased use to reduce the burden of knee PJI for patients, and for the healthcare system. Cite this article: Bone Joint Res 2022;11(10):690–699

Abstract. Introduction. There is a longstanding presumed association between obesity, complications, and revision surgery in primary knee arthroplasty. This has more recently been called into question, particularly in centres where a high volume of arthroplasty is performed. We investigated the correlation between Body Mass Index (BMI), mortality, and revision surgery. Method. This was a cohort study of at least 10 years following primary knee arthroplasty from a single high volume arthroplasty unit. Mortality and revision rates were collected from all patients who underwent primary knee arthroplasty between 2009 and 2010. Kaplan Meier analysis was performed. Results. There were 1161 female and 948 male patients with a mean age of 69 (21 to 97). All cause survivorship excluding mortality was 97.2% up to 13yrs with a minimum of 10 years. The revision rate in this series was 2.8% with no significant difference in revision rates after 10 year between patients with BMI above and below 40 (p=0.438). There was no significant difference in 10-year mortality between patients above and below a BMI of 40 (p=0.238). Conclusion. This study shows no significant difference in the long term survival of total knee replacement between patients with normal and high BMI. Careful consideration should be given before rationing surgery based on BMI alone

There is a longstanding presumed association between obesity, complications, and revision surgery in primary knee arthroplasty. This has more recently been called into question, particularly in centres where a high volume of arthroplasty is performed. We investigated the correlation between Body Mass Index (BMI), mortality, and revision surgery. This was a cohort study of at least 10 years following primary knee arthroplasty from a single high volume arthroplasty unit. Mortality and revision rates were collected from all patients who underwent primary knee arthroplasty between 2009 and 2010. Kaplan Meier analysis was performed. There were 1161 female and 948 male patients with a mean age of 69 (21 to 97). All cause survivorship excluding mortality was 97.2% up to 13yrs with a minimum of 10 years. The revision rate in this series was 2.8% with no significant difference in revision rates after 10 year between patients with BMI above and below 40 (p=0.438). There was no significant difference in 10–year mortality between patients above and below a BMI of 40 (p=0.238). This study shows no significant difference in the long term survival of total knee replacement between patients with normal and high BMI. Careful consideration should be given before rationing surgery based on BMI alone

Aims. This study investigates whether primary knee arthroplasty (KA) restores health-related quality of life (HRQoL) to levels expected in the general population. Methods. This retrospective case-control study compared HRQoL data from two sources: patients undergoing primary KA in a university-teaching hospital (2013 to 2019), and the Health Survey for England (HSE; 2010 to 2012). Patient-level data from the HSE were used to represent the general population. Propensity score matching was used to balance covariates and facilitate group comparisons. A propensity score was estimated using logistic regression based upon the covariates sex, age, and BMI. Two matched cohorts with 3,029 patients each were obtained for the adjusted analyses (median age 70.3 (interquartile range (IQR) 64 to 77); number of female patients 3,233 (53.4%); median BMI 29.7 kg/m. 2. (IQR 26.5 to 33.7)). HRQoL was measured using the three-level version of the EuroQol five-dimension questionnaire (EQ-5D-3L), and summarized using the Index and EuroQol visual analogue scale (EQ-VAS) scores. Results. Patients awaiting KA had significantly lower EQ-5D-3L Index scores than the general population (median 0.620 (IQR 0.16 to 0.69) vs median 0.796 (IQR 0.69 to 1.00); p < 0.001). By one year postoperatively, the median EQ-5D-3L Index score improved significantly in the KA cohort (mean change 0.32 (SD 0.33); p < 0.001), and demonstrated no clinically relevant differences when compared to the general population (median 0.796 (IQR 0.69 to 1.00) vs median 0.796 (IQR 0.69 to 1.00)). Compared to the general population cohort, the postoperative EQ-VAS was significantly higher in the KA cohort (p < 0.001). Subgroup comparisons demonstrated that older age groups had statistically better EQ-VAS scores than matched peers in the general population. Conclusion. Patients awaiting KA for osteoarthritis had significantly poorer HRQoL than the general population. However, within one year of surgery, primary KA restored HRQoL to levels expected for the patient’s age-, BMI-, and sex-matched peers. Cite this article: Bone Joint J 2023;105-B(4):365–372

Aims. The aim of this study was to assess factors associated with the estimated lifetime risk of revision surgery after primary knee arthroplasty (KA). Methods. All patients from the Scottish Arthroplasty Project dataset undergoing primary KA during the period 1 January 1998 to 31 December 2019 were included. The cumulative incidence function for revision and death was calculated up to 20 years. Adjusted analyses used cause-specific Cox regression modelling to determine the influence of patient factors. The lifetime risk was calculated as a percentage for patients aged between 45 and 99 years using multiple-decrement life table methodology. Results. The estimated lifetime risk of revision ranged between 32.7% (95% confidence interval (CI) 22.6 to 47.3) for patients aged 45 to 49 years and 0.6% (95% CI 0.1 to 4.5) for patients aged over 90 years. At 20 years, the overall cumulative incidence of revision (6.8% (95% CI 6.6 to 7.0)) was significantly less than that of death (66.3% (95% CI 65.4 to 67.1)). Adjusted analyses demonstrated converse effect of increasing age on risk of revision (hazard ratio (HR) 0.5 (95% CI 0.5 to 0.6)) and death (HR 3.6 (95% CI 3.4 to 3.7)). Male sex was associated with increased risks of revision (HR 1.1 (95% CI 1.1 to 1.2); p < 0.001) and death (HR 1.4 (95% CI 1.3 to 1.4); p < 0.001). Compared to patients undergoing primary KA for osteoarthritis, patients with inflammatory arthropathy had a higher risk of death (HR 1.7 (95% CI 1.7 to 1.8); p < 0.001), but were less likely to be revised (HR 0.9 (95% CI 0.7 to 1.0); p < 0.001). Patients with a greater number of comorbidities (HR 1.4 (95% CI 1.3 to 1.4)) and greater levels of socioeconomic deprivation (HR 1.4 (95% CI 1.4 to 1.5)) were at increased risk of death, but neither increased the risk of revision. Conclusion. The estimated lifetime risk of revision KA varied depending on patient sex, age, and underlying diagnosis. Patients aged between 45 and 49 years had a one in three risk of undergoing revision surgery within their lifetime, which decreased with age to one in 159 in those aged 90 years or more. Cite this article: Bone Joint J 2022;104-B(12):1313–1322

Aims. The metabolic equivalent of task (MET) score examines patient performance in relation to energy expenditure before and after knee arthroplasty. This study assesses its use in a knee arthroplasty population in comparison with the widely used Oxford Knee Score (OKS) and EuroQol five-dimension index (EQ-5D), which are reported to be limited by ceiling effects. Methods. A total of 116 patients with OKS, EQ-5D, and MET scores before, and at least six months following, unilateral primary knee arthroplasty were identified from a database. Procedures were performed by a single surgeon between 2014 and 2019 consecutively. Scores were analyzed for normality, skewness, kurtosis, and the presence of ceiling/floor effects. Concurrent validity between the MET score, OKS, and EQ-5D was assessed using Spearman’s rank. Results. Postoperatively the OKS and EQ-5D demonstrated negative skews in distribution, with high kurtosis at six months and one year. The OKS demonstrated a ceiling effect at one year (15.7%) postoperatively. The EQ-5D demonstrated a ceiling effect at six months (30.2%) and one year (39.8%) postoperatively. The MET score did not demonstrate a skewed distribution or ceiling effect either at six months or one year postoperatively. Weak-moderate correlations were noted between the MET score and conventional scores at six months and one year postoperatively. Conclusion. In contrast to the OKS and EQ-5D, the MET score was normally distributed postoperatively with no ceiling effect. It is worth consideration as an arthroplasty outcome measure, particularly for patients with high expectations. Cite this article: Bone Jt Open 2023;4(3):129–137

Introduction and Objectives: Currently it has become popular to use cement impregnated with antibiotics in revisions of septic total knee replacements. However, the use of cement with antibiotics in primary knee arthroplasties continues to be a cause of controversy. However, contrary to American opinion, in some European studies it has been seen that the use of cement with antibiotics decreases the infection rate in primary knee arthroplasties. Materials and Methods: We hereby present a comparative study of 642 patients that underwent primary total knee replacement (TKR) (Legacy-Zimmer) between 2003 and 200. We divided the patients into 2 groups. One group of 296 patients underwent primary TKR using cement without antibiotic. A second group of 346 patients underwent primary TKR using gentamycin-loaded cement. Mean follow-up was 1 year. Our aim was to find differences in postoperative infection rates during the first year of follow-up. Results: We found no differences in demographic variables, operation time, ischemia time, rate of transfusions, days of hospitalization or medical complications. We saw 10 infections (3.3% infection rate) in group 1. We saw 3 infections (0.09 % infection rate) in group 2. We carried out a comparative statistical analysis and it was significant. Discussion and Conclusions: Cement impregnated with gentamycin is effective in the prevention of deep infection in the short and medium term in primary total knee replacement

Abstract. INTRODUCTION. This study investigates whether primary knee arthroplasty (KA) restores health-related quality of life (HRQoL) to levels expected in the general population. METHODOLOGY. This retrospective case-control study utilises two sources: patients undergoing primary KA from a University Teaching hospital; and individual-level data from the Health Survey for England which was used to represent the General Population. Propensity score matching was used to balance covariates (sex, age and body mass index (BMI)) and facilitate group comparisons. Two matched cohorts with 3029 patients each were obtained for the adjusted analyses (median age 70.3 interquartile range (IQR) 64–77; Female sex 3233 (53.4%); median BMI 29.7 IQR 26.5-33.7). HRQoL was measured using the three-level version of the EuroQol 5-Dimensions’ (EQ-5D-3L) Index and EQ-VAS scores. RESULTS. Patients awaiting KA had significantly lower EQ-5D-3L Index scores than the General Population (median 0.620 (IQR 0.16-0.69) vs median 0.796 (IQR 0.69-1.00), p<0.001). By one-year post-operation, the median EQ-5D-3L Index score improved significantly in the KA cohort (mean change 0.32 (Standard deviation 0.33), p<0.001), and demonstrated no significant differences when compared to the General Population (0.796 (IQR 0.69-1.00) vs 0.796 (0.69-1.00), p=1.0). Older age-groups had statistically better Index scores than matched peers in the General Population. Compared to the General Population cohort, the post-operative EQ-VAS was significantly higher in the KA cohort (p<0.001). CONCLUSION. Patients awaiting KA for osteoarthritis have significantly poorer HRQoL than the General Population. However, within one year of surgery, primary KA restored HRQoL to levels expected for patient's age, BMI and sex-matched peers

Aims. The aim of this study was to identify variables associated with time to revision, demographic details associated with revision indication, and type of prosthesis employed, and to describe the survival of hinge knee arthroplasty (HKA) when used for first-time knee revision surgery and factors that were associated with re-revision. Methods. Patient demographic details, BMI, American Society of Anesthesiologists (ASA) grade, indication for revision, surgical approach, surgeon grade, implant type (fixed and rotating), time of revision from primary implantation, and re-revision if undertaken were obtained from the National Joint Registry data for England, Wales, Northern Ireland, and the Isle of Man over an 18-year period (2003 to 2021). Results. There were 3,855 patient episodes analyzed with a median age of 73 years (interquartile range (IQR) 66 to 80), and the majority were female (n = 2,480, 64.3%). The median time to revision from primary knee arthroplasty was 1,219 days (IQR 579 to 2,422). Younger age (p < 0.001), decreasing ASA grade (p < 0.001), and indications for revision of sepsis (p < 0.001), unexplained pain (p < 0.001), non-polyethylene wear (p < 0.001), and malalignment (p < 0.001) were all associated with an earlier time to revision from primary implantation. The median follow-up was 4.56 years (range 0.00 to 17.52), during which there were 410 re-revisions. The overall unadjusted probability of re-revision for all revision HKAs at one, five, and ten years after surgery were 2.7% (95% confidence interval (CI) 2.2 to 3.3), 10.7% (95% CI 9.6 to 11.9), and 16.2% (95% CI 14.5 to 17.9), respectively. Male sex (p < 0.001), younger age (p < 0.001), revision for septic indications (p < 0.001) or implant fracture (p = 0.010), a fixed hinge (p < 0.001), or surgery performed by a non-consultant grade (p = 0.023) were independently associated with an increased risk of re-revision. Conclusion. There were several factors associated with time to first revision. The re-revision rate was 16.2% at ten years; however, the risk factors associated with an increased risk of re-revision could be used to counsel patients regarding their outcome. Cite this article: Bone Joint J 2023;105-B(1):47–55

This study aims to determine the lifetime risk of revision surgery after primary knee arthroplasty (KA). The Scottish Arthroplasty Project dataset was utilised to identify all patients undergoing primary KA during the period 1998–2019. The cumulative incidence function for revision and death was calculated and adjusted analyses utilised cause-specific Cox regression modelling to determine the influence of patient-factors. The lifetime risk was calculated for patients aged between 45–99 years using multiple decrement lifetable methodology. The lifetime risk of revision ranged between 32.7% (95% Confidence Interval (CI) 22.62–47.31) for patients aged 45–49 years and 0.63% (95%CI 0.1–4.5) for patients aged over 90 years. Adjusted analyses demonstrated the converse effect of age on revision (Hazard Ratio (HR) 0.5, 95%CI 0.5–0.6) and death (HR 3.5, 95%CI 3.4–3.7). Male sex was associated with increased risks of revision (HR 1.1, 95%CI 1.1–1.2) and death (HR 1.4, 95%CI 1.3–1.4). Patients with inflammatory arthropathy had a higher risk of death (HR 1.7, 95%CI 1.7–1.8), but were less likely to be revised (HR 0.85, 95%CI 0.74–0.98) than those treated for osteoarthritis. Patients with greater number of comorbidities and greater levels of socio-economic deprivation were at increased risk of death, but neither increased the risk of revision. The lifetime risk of revision knee arthroplasty varies depending on patient sex, age at surgery and underlying diagnosis. Patients aged between 45 and 49 years have a one in three probability of revision surgery within their lifetime. Conversely, patients aged 90 years or over were very unlikely to experience revision

Introduction. The purpose of this study was to examine the effects of baseline mental health on functional outcomes after primary knee arthroplasty by reviewing the data collected in a multi-centre prospective observational cohort study. We hypothesised that those patients with lower baseline mental health status would demonstrate significantly worse outcomes vs their counterparts with higher mental status following primary total knee arthroplasty. Methods. Data from a multi-centre prospective cohort study of PS (posterior stabilising implant) and CR (cruciate retaining implant) primary knee arthroplasty were compared to determine the relationship between baseline mental health status and functional outcomes post-surgery. Subjects were followed from the time of the index surgery to monitor outcomes and complications. Validated quality of life instruments, including SF-36, WOMAC, Knee Society Score, and an activity scale were used. Changes from baseline to 1 year on the SF-36 and WOMAC were evaluated. Regression analysis was completed to assess changes in WOMAC based on baseline SF-36 scores. All analyses were adjusted for age, BMI, gender, and implant type. Results. Baseline data was available for 436 subjects in the primary PS study and 493 subjects in the primary CR study. Patients improved significantly on all SF-36 and WOMAC components between baseline and 12 months post-surgery. Correlation and regression analysis between WOMAC and SF-36 showed that Global Health (GH), Mental Health (MH), Role-Emotional (RE), and Mental Component Score (MCS) subscales on the SF-36 were significantly associated with positive post-operative changes in WOMAC scores. Conclusion. This study examined the effects of baseline mental health on functional outcomes after primary knee arthroplasty and found that baseline mental health was a significant predictor of functional outcomes twelve months after surgery. This relationship between mental health and outcomes needs to be examined carefully to help surgeons better prepare their patients for surgery

Introduction. A smartphone-based care platform allows a customizable educational and exercise interface with patients, allowing many to recover after surgery without the need for formal physical therapy (PT). Furthermore, advances in wearable technology to monitor physical activity (PA) provides patients and physicians quantifiable metrics of the patient's recovery. The purpose of this study is to determine the feasibility of a smartphone-based exercise educational platform after primary knee arthroplasty as well as identifying factors that may predict the need for formal physical therapy. Methods. This study is part of a multi-institution, prospective study of patients after primary total knee arthroplasty (TKA) and partial knee arthroplasty (PKA) enrolled in a smartphone with smartwatch-based episode of care platform that recorded multimodal PA (steps, kcal, stairs). Postoperatively, all patients initially followed the smartphone-based exercise program. At the surgeon's discretion, patients were prescribed therapy if needed. The outcome of this study was the need for PT outside the app-based exercise program as well as time to return to preoperative step count. Variables assessed were preoperative weekly step counts (steps/day), weekly postoperative activity level (weekly step count compared to preoperative level), compliance with the exercise program (>75% completion) and patient demographic data including gender, age, BMI and narcotic use. One hundred eighty-eight patients were included in analysis: 45 PKA (24%) and 143 TKA (76%). Step count data was available on 135 patients and physical therapy data on 174. Results. Overall educational compliance was 91% and exercise compliance 34%. By 4-weeks postop, 45.6% of patients reached or exceeded their preoperative step count, including 60% of PKA and 41% of TKA (p=0.05). There was no significant difference in reaching step count based on gender (p=0.7), BMI <40kg/m2 (p=0.9) or age <65-years old (p=0.67). Sixty-three percent of patients that were compliant with the exercise program reached the step count compared to 40% of patients that weren't complaint (p=0.01). One hundred thirty-three patients (76.4%) completed the app-based exercise program without the need for PT, which included 81.4% of PKA patients and 75% of TKA patients (p=0.38). Weekly compliance with the exercise program (>75%) was significantly associated with not needing PT (p<0.001). Other factors that were significantly associated with the need for PT were a high physical activity level in postoperative week 1 (p<0.001) and a low physical activity level in postoperative week 2 (p=0.002). Conclusion. A high percentage of patients after primary knee arthroplasty were able to successfully complete the smartphone-based exercise program without the need for PT. Compliance with the exercise program was an important predictor of success. Postoperative activity level may also indicate the need for therapy as patients who were very active in the first postoperative week and then saw a decline in activity in the second week were more likely to be prescribed PT. With this platform, surgeons can monitor a patient's exercise compliance and postoperative activity level allowing many to recover at home, while being able to identify those within the first few weeks who may need structured physical therapy. For figures, tables, or references, please contact authors directly

Infection after total knee replacement, which is a serious and expensive complication, often represent a diagnostic and therapeutic problem. The current incidence of infection after the primary procedure is 1 to 3%, depending on the published series. A correct and timely diagnosis, classification between early and delayed infection, and which microorganisms are involved, are crucial steps in defining prevention and treatment strategies. Determination of the annual and three years incidence of infection after primary total knee replacement; evaluation of the microorganisms involved and its resistance patterns; assessment of treatment – surgical approach and selection of antibiotics. Collection of clinical and laboratorial data of all patients who underwent primary total knee arthroplasty between 2011 and 2013 in our hospital; definition of periprosthesic infection cases following the Musculoskeletal Infection Society (MSIS) criteria. During the study period, 526 primary knee replacements were performed in 521 patients; with 41 patients having bilateral replacements. The mean follow-up period was 30 months; 5 patients had no follow up and 1 died in the post operatory. We reported 9 prosthetic infections, of which 2 did not reached the MSIS criteria, but were also considered based on high clinical suspicion. The majority of the cases (6) were delayed infections. The calculated 3 year incidence of infection after primary knee replacement was 1,6%, with annual rates of 3,0% (2011), 1,7% (2012) and 0,9% (2013). The microorganisms isolated were as follows: Staphylococcus aureus and coagulase-negative staphylococci, resistant to penicillin; Streptococcus agalactiae and one isolate of Serratia marcescens, both showing multiple antibiotic resistances. Only one case was treated with surgical debridement and conservation of prosthesis, in the other 8 cases a two-stage implant revision procedure was performed. The antibiotics selected were vancomycin, fluoroquinolones and association of gentamicin and clindamycin. Our local infection rates are in line with the published series from reference surgical centers. The annual incidence is decreasing, probably because the majority of our infection cases are delayed (recent years, shorter follow up period) and our preventive measures are improving. The microorganisms identified are also in agreement with published data, and our antibiotic resistance pattern is a valuable information to consider in a first empirical approach. Treatment options suitable to each case, and antibiotic protocols need to be improved in our local practice. Preventive measures in delayed infections are still under debate, and represent another future challenge

Purpose: The purpose of this study was to examine the effects of baseline mental health on functional outcomes after primary knee arthroplasty by reviewing the data collected in a multi-center prospective observational cohort study. We hypothesized that those patients with lower baseline mental health status would demonstrate significantly worse outcomes vs. their counterparts with higher mental status following primary total knee arthroplasty. Method: Data from a multi-center prospective cohort study of PS (posterior stabilizing implant) and CR (cruciate retaining implant) primary knee arthroplasty were compared to determine the relationship between baseline mental health status and functional outcomes post-surgery. Subjects were followed from the time of the index surgery to monitor outcomes and complications. Validated quality of life instruments, including SF-36, WOMAC, Knee Society Score, and an activity scale were used. The rates of improvement from 0 to 12 months were analyzed for this study. Results: Baseline data was available for 436 subjects in the primary PS study and 493 subjects in the primary CR study. Patients improved significantly on all SF-36 and WOMAC components between baseline and 12 months post-surgery. Correlation and regression analysis between WOMAC and SF-36 showed that Global Health (GH), Mental Health (MH), and Mental Component Score (MCS) subscales on the SF-36 were significantly associated with positive post-operative changes in WOMAC scores. Conclusion: This study examined the effects of baseline mental health on functional outcomes after primary knee arthroplasty and found that baseline mental health was a significant predictor of functional outcomes twelve months after surgery. This relationship between mental health and outcomes needs to be examined carefully to help surgeons better prepare their patients for surgery

Background. The purpose of this study is to evaluate the early perioperative outcomes after primary knee arthroplasty with the use of a smartphone-based exercise and educational platform compared to a standard of care control group. Methods. A multicenter prospective randomized control trial was conducted evaluating the use of the mymobility smartphone-based care platform for primary total knee arthroplasty (TKA) and unicondylar knee arthroplasty (UKA). Patients in the control group (224 patients) received the respective institution's standard of care typically with formal physical therapy. Those randomized to mymobility treatment group (192 patients) were provided an Apple Watch and mymobility smartphone application. The treatment group was not initially prescribed physical therapy, but could if their surgeon determined it necessary. Early outcomes assessed included 90-day knee range of motion, KOOS Jr scores, 30-day single leg stance (SLS) time, Time up and Go (TUG) time and need for manipulation under anesthesia (MUA). There was no significant difference in age, BMI or gender between groups. Results. The 90-day knee flexion was not significantly different between controls (118.3±11.8) and mymobility (118.8 ±12) (p=0.7), nor was knee extension (1.6 ±3.5 vs. 1 ±3.1, p=0.16). KOOS Jr scores were not significantly different between control group (74 ±13.1) and mymobility group (71 ±13.3) (p=0.06). 30-day SLS was 22.3 ± 19.5 sec in controls and 24 ± 20.8 sec in mymobility (p=0.2). 30-day TUG times were 16 ± 44.3 sec in control and 15 ± 40.6 sec in mymobility (p=0.84). MUAs were performed in 4.02% of patients in the control group and 2.8% in the mymobility group (p=0.4%). Conclusion. The use of the mymobility care platform demonstrated similar early outcomes to traditional care models, while providing communication and insights into patient engagement with the care plan. There was no significant difference in 90-day range of motion or need for MUA

The Trent Arthroplasty Audit Group (TAAG) has been prospectively collecting data on primary knee arthroplasty since 1990 and revision procedures since 1992. To date details of 27 000 primary and 1300 revision knee arthroplasties, from both teaching and district general hospitals in the Trent region, have been contributed. This provides us with a unique opportunity to look at the outcome of total knee arthroplasty across an English region, at 10 or more years of follow-up. A questionnaire was designed, with assistance from the department of epidemiology and public health, including both generic (EuroQol) and knee specific questions. Patients who underwent primary knee arthroplasty from 1990–92 were included in the study (4420 patients). Surviving patients (65%) were traced using the NHSIA patient tracing service and the questionnaire was administered by post with a response rate was 55%. The mean length of follow-up was 11 years 7 months and the mean age at the time of follow-up was 78 years. The vast majority (86%) of patients were satisfied with their joint replacement. Although 52 % took prescribed analgesia for pain in their knee, 22% still complained of pain often or all the time. 18% felt their knee totally or greatly interfered with their usual activities. 14% of patients reported re-operation on their knee, of which 11% were revision procedures. This suggests that a significant number of patients experience pain and/or disability at 10 or more years following knee replacement. Since most GPs have a high threshold for re-referral in this group of patients, it is likely that the degree of morbidity has previously been underestimated in the orthopaedic community

We discuss the role of primary knee arthroplasty in supracondylar and intercondylar fractures of the femur in elderly patients with reference to 13 cases. This method of treatment is shown to be effective and to have good results. It is recommended for all type C and some type A supracondylar fractures in old people

Aims: To report the outcome of secondary patellar resurfacing in patients with chronic anterior knee pain following primary total knee replacement. Methods: A total of twenty patients identified over a 10-year period from 623 patients managed without patellar replacement during primary knee arthroplasty were included and evaluated pre and postoperatively using the American Knee Society (AKS) score, as well as by radiological analysis. Results: The mean follow up was 36.1 months (range 12–104 months). The mean knee score improved from 46.7 to 62.2 points while the mean functional score increased from 44.7 to 52.2 points. Only 44.5% of the patients reported some improvement whereas the remaining reported no change or deterioration. Postoperative radiographic alignment of the primary knee arthroplasty did not influence outcome of secondary patellar resurfacing. Complications were noted in 6 of the 20 patients including patella fracture, patella instability and loss of a range of movement. Conclusions: Anterior knee pain following knee arthroplasty remains a difficult condition to manage and secondary resurfacing of the patella is clearly not to be advocated in all patients since it may well increase patient dissatisfaction and hasten revision

Introduction. Although we know that smoking damages health, we do not know impact of smoking on a patient's outcome following primary knee arthroplasty (KA). In the UK, clinical commissioning groups (CCGs) have the authority (& funds) to commission healthcare services for their communities. Over the past decade, an increasing number of CCGs are using smoking as a contraindication for patients with end-stage symptomatic knee arthritis being referred to a specialist for due consideration of KA without any clear evidence of the associated risks & benefits. The overall objective of this study is to compare clinical outcomes after knee arthroplasty surgery in smokers, ex-smokers & non-smokers. Methods. We obtained data from the UK Clinical Research Practice Datalink (CPRD) that contains information on over 11 million patients (7% of the UK population) registered at over 600 general practices. CPRD data was linked to Hospital Episode Statistics, hospital admissions & Patient Reported Outcome Measures (PROMs) data. We collected data on all KAs (n=64,071) performed over a 21-year period (1995 to 2016). Outcomes assessed included: local & systemic complications (at 6-months post-surgery): infections (wound, respiratory, urinary), heart attack, stroke & transient ischaemic attack, venous thromboembolism, hospital readmissions & GP visits (1-year), analgesic use (1-year), surgical revision (up to 20-years), mortality (90-days and 1-year), & 6-month change from pre-operative scores in Oxford Knee Score (OKS). Regression modelling is used to describe the association of smoking on outcomes, adjusting for confounding factors. Results. Smoking was associated with an increased risk of lower respiratory tract infections (LRTI) (4.2% smokers vs. 2.7% non-smokers) (Odds Ratio (OR) 0.76, p-value 0.017). LRTI were similar in ex-smokers & smokers at 3.9%. There was no association with any of the other 6-month complications. Pain medication use over 1-year post surgery was higher in smokers compared to non-smokers: gabapentinoids 7.4% vs. 5.2% (OR 0.74, p< 0.001), opioids 45.9% vs. 35.3% (OR 0.79, p< 0.001), NSAIDs 51.6% vs. 46.1% (OR 0.91, p = 0.044). Mortality was higher in smokers at 1-year compared to non-smokers (hazard ratio (HR) 0.53, p<0.001) & ex-smokers (HR 0.65, p = 0.037), but there was no difference observed at 90-days. There was no association of smoking on revision surgery over 20-years follow up. Smoking was associated with worse postoperative OKS being 3.1 points higher in non-smokers (p<0.001) & 3.0 points higher in ex-smokers (p<0.001). The overall change in OKS before & after surgery was 13.9 points in smokers versus 16.3 points in non-smokers (p<0.001) & 15.7 points in ex-smokers (p<0.001). Over the year following surgery, smokers were more likely to visit their GP, but there was no association with hospital readmission rates. Conclusion. This is the largest study with linked primary care & secondary care data highlighting impact of a preventable patient factor on outcome of a routinely performed planned intervention. Smokers achieved clinical meaningful improvements in patient reported pain & function (OKS) following KA, although their attained post-operative OKS was lower than in non-smokers & ex-smokers. Levels of pain medication use were notably higher in both smokers & ex-smokers. As smokers achieved good clinical outcomes following KA surgery, smoking should not be a barrier to referral for or consideration of KA. However, the study does highlight particular risks a patient is taking if he/she continues to smoke when being considered for elective knee arthroplasty. This study will help the family physicians as well as patients to make an informed decision on whether to go ahead with a planned intervention whilst patient continues to be an active smoker or not. Key Words: Knee Arthroplasty, Smoking, Patient Reported Outcomes, Epidemiology, Complications