Introduction: Obesity and older age have been shown to predict poorer postoperative outcomes in prior knee reconstruction studies. The purpose of this study is to evaluate the risks that these comorbidities have on postoperative outcomes of patients who underwent medial patellofemoral ligament (MPFL) reconstruction. Methods: The National Surgical Quality Improvement Program was queried to identify MPFL reconstruction patients between 2008 and 2016. Subjects having simultaneous ligamentous knee repair and not undergoing MPFL reconstruction for patellar instability were excluded. Patients were stratified by obesity (cut-off of 30 kg/m2), age (cut-off of 30), and postoperative complications. Binary logistic regression determined the impact of obesity and older age on adverse events. Results: 476 MPFL reconstructions were isolated. 44% had a BMI ≥30 kg/m2 and 39% of patients were older than 30. Rates of complications, reoperation, and readmission were 1.9%, 0.8%, and 1.1% respectively. No significant differences in complication, reoperation, or readmission rates were observed between BMI groups (all, p>0.05). Patients >30 were significantly more likely to experience a complication (4.4% vs 0.3%, p=0.003) or undergo a reoperation (2.7% vs 0% p=0.021). Patients >30 were significantly more likely to experience an adverse postoperative event (OR=8.6 95% CI [1.9 – 40.0], p=0.006). Conclusion: Following MPFL reconstruction for patellar instability, despite BMI posing no observable impact on operative outcomes, patients greater than 30 were nearly 9 times more likely to have an adverse postoperative outcome.

Background and study aims
Focal femoral resurfacing implants have been developed as a treatment option for patients with full-thickness cartilage lesions. They are typically offered for middle-aged patients who are deemed too young for conventional arthroplasty, but also not suitable for biological procedures. This study aims to critically appraise and evaluate the evidence pertaining to these devices.
Material and methods
Using the search terms: HemiCAP, UniCAP, Episurf, focal, femoral, condyle, inlay and resurfacing, we reviewed the PubMed, EMBASE and the Cochrane Database of Systematic Reviews to find any articles published up to March 2020.
Results
14 papers met the inclusion criteria, reporting on four different prosthetic devices. The HemiCAP, BioPoly, and Episealer are designed to be used in lesions <3.1cm2; whilst the UniCAP can be used in larger lesions and in areas of localised OA. The mean conversion rate for the implants designed to treat smaller lesions was 6.2% at 2 years, and 18.8% at 5-7 year follow-up. For the UniCAP device, the survivorship is reported to be approximately 40% at 9 years. We observed favourable short-term functional scores however there is a lack of robust medium and long-term data.
Conclusion
Our study suggests that survivorships results with these implants is still unpredictable. If there is a potential subgroup of patients who benefit from focal femoral resurfacing, their selection criteria needs to be refined. This would suggest that as present these implants should be used cautiously, and only in well-designed clinical trials.

Introduction: dissatisfaction after TKA can achieve more than 25%. The pain remains the first reason in most cases. Identification of pain cause can turn to become a challenge for the surgeon. The goal of the study was to identify the reasons of pain syndrome basing on examination algorithm. Methods: in our prospective study we analyzed 113 patients with chronic knee pain after primary TKA from 2016 to 2018. All patients included into the study underwent step by step examination algorithm: anamnesis, standard and longstanding X-Ray, CT, ESR,CRP, aspiration test, culture isolation. Synovial fluid was obtained in 102 (90.2%) from, in 11 patients were “dry tap”. Results: periprosthetic joint infection was isolated in 55 patients (48.8%). Among the septic patients the WBC level in PJI was above 3000 In 100% of cases. PMN (>70%) was in 47 ( 85.6%) patients. In septic group ESR was positive in 84%, CRP was positive in 55%. After the aspiration series test PJI was proved only in 52 patients. Seven cases (6,2%) were with microbial contamination. Coagulase-negative staphylococci was obtained in 64%, 23.4% - Staphylococcus Aureus, 8.2% - Culture-Negative PPI, 16.4% - polymicrobial infection. We confirmed a combination of PJI with another pain reasons in 17 patients (21.5%). Conclusion: the main reason of pain after TKA is PJI. For PJI verification it is necessary strictly adhere to the complex diagnostics algorithm. In cases of doubtful data, it is necessary to perform up to 3 aspirations.

The UK National Joint Registry (UKNJR) is the single largest joint registry reaching its 17th year and amassing a patient population base of 1.3 million.

Current estimations of knee prosthesis longevity stem from international joint registries and case series which tend to be of modest size and lower quality respectively. We aimed to use the largest currently available registry to examine the expected survival of total knee replacements(TKRs), unicondylar knee replacements (UKRs) and patellofemoral knee replacements (PFRs) at 10 and 15 years based on both construct brand and fixation technique (cemented vs uncemented) as both have been implicated as fundamental to prosthesis survival.

From our (UKNJR) data, the all-cause survivorship of TKRs at 10 and 15 years is 96.7% and 95.4% respectively. For UKRs it is 89.8% and 80.7% and for PFRs it is 81.6% and 76.5%. When 10 and 15 year all-cause survivorship is compared between fixation techniques, cemented and uncemented TKRs show similar survivorship at both time points. For UKRs uncemented constructs showed improved survivorship compared to cemented at 10 years (92.7% vs 88.2%, p <0.001). This improved survivorship was even greater amongst those <65 years of age. In fact all construct types regardless of fixation showed increased rate of revision in those <65 vs those ≥65.

Most knee replacmeents should outlive the average recipient however young patients, particularly those receiving UKRs, are prone to greater revision risks across all types of knee replacements and evidence suggests that uncemented fixation may offer improved joint survival in these patients.

Introduction: Navigated TKA is still discussable in the literature. Now orthopаedic surgeons research robotic technologies in TKA. Materials and methods: From 2008 we performed more than 1500 navigated TKA with different deformities. We isolated two groups of patients: 150 navigated TKA and 150 convenient replacements. We divided each group in 3 parts with severe (>20 0) varus, valgus (>20 0) and extraarticular deformities, 50 patients in each group. Mean follow up time in booth groups was 86 months (from 78 to 252). The functional result was evaluated by KSS, Oxford and WOMAC scales. We analyzed navigation protocols in navigated groups. The implant survival evaluated by revision at any reason. Results and discussion: we identified mean implant survival in navigated groups: varus- 92,3%, valgus – 86,4 %, extraarticular deformities - 88,7%. In control group: varus- 89,4%, valgus – 82,4 %, extraarticular deformities - 80,3%. The scales showed better results in navigated groups. The main reason for revision was aseptic loosening, the second reason was infection, and it was almost equal in all groups. Moreover, greater difference was between valgus and extraarticular groups. In valgus deformity additional hyperextension was isolated in 36 cases in navigated group. Navigated distal femur resection can be done more proper by navigation. In extraarticular group the proper cuts by navigation system were proofed by navigation protocols. The grate difference in 8,4% of loosening in control group can be explainable, because in extraarticular deformity it is difficult to do the proper cuts and balancing.

Aims: The primary aim was to assess whether preoperative anaemia was associated with a worse knee specific functional outcome after total knee arthroplasty (TKA). The secondary aims were to assess the influence of preoperative anaemia on generic health and patient satisfaction following TKA. Methods: During a one-year period 497 patients undergoing TKA with complete pre and postoperative data, which included 215 (43.3%) male and 282 (56.7%) female patients, with an overall mean age of 70.0 (range 45 to 93) years. Patient demographics, comorbidities, pre and postoperative Oxford knee score (OKS), EuroQol 5 dimension (EQ-5D), and postoperative (one-year) forgotten joint score (FJS) and patient satisfaction were collected. Results: There were 56 (11.3%) patients that were defined as having preoperative anaemia and were significantly older (4.6 years, p<0.001) and were more likely to have COPD (p=0.004), connective tissue (p=0.047) or kidney disease (p=0.011) compared to the group without preoperative anaemia. There was however no significant difference in the preoperative OKS (p=0.752) or EQ-5D (p=0.762) scores between the groups. When adjusting for confounding differences between the groups, there was a significantly lower postoperative OKS (-3.0 points, p=0.035) and FJS (-11.6 points, p=0.011) associated with the anaemia group. There was no significant difference in patient satisfaction at one year following surgery between the groups (odds ratio 0.84, 95% confidence interval 0.62 to 1.53, p=0.976). Conclusion: Preoperative anaemia is associated with a lower postoperative joint specific functional outcome, but whether these differences are clinically meaningful is not clear, with difference in patient satisfaction being observed.

Purpose: Complex regional pain syndrome (CRPS) type I is a condition with chronic pain condition following a trauma or surgery. The physiopathology of this syndrome remained incompletely known. Due to the lack of effective curative treatment, prevention of this complication is important. Therefore, we evaluated the efficacy of vitamin C in preventing this complication. Material and methods: We conducted a prospective randomized study on the efficiency of vitamin C (one group with and one without vitamin C) on prevention of CRPS risk in patients operated in our institution with TKA. Patients with a VAS pain score > 4 performed a three-phase bone scintigraphy. The diagnostic of CRPS was made by using the Budapest criteria associated to a bone scintigraphy. Statistical significance was set at p < 0.05. Results: 153 were included in the vitamin C group, 139 in the control group without vitamin C. For the entire cohort, the prevalence of complex regional pain syndrome was 7.9% (23 of 292). The prevalence of complex regional pain syndrome was 3.9% (six of 153) in the vitamin C group and 12.2% (seventeen of 139) in the control group (p = 0.008). After multivariate regression, vitamin C was found to be an independent preventive factor of CRPS and there was a significant difference between the vitamin C group and the control group (relative risk, 0.27; 95% confidence interval, 0.1–0.8; p = 0.015). Conclusion: Taking 1 g per day of vitamin C during 40 days after a TKA reduces the risk of CRPS.

Introduction: Some authors have postulated that different risk factors are involved in the development of tibiofemoral osteoarthritis, but only a few tried to distinguish between the etiology of medial and lateral osteoarthritis. Objectives: To study the effect of hip and pelvic geometry on the knee osteoarthritis to prove whether it had relation to biomechanics of the hip joint. Methodology: Hospital based descriptive observational study, in Sudanese patients with knee pain seen at ShargElneel hospital from August 2015 To October 2016. Patients were assessed both clinically, radiologically using scanogram and questionnaires. Results: 60 patients were enrolled in this study, 53.3% are females and all of them are in the middle and elderly age groups (41-80 year). The most prevalent deformity was Varus deformity 63.3% by clinical examination and 75% by radiological measurement. a statistically significant correlation was found between Clinical assessment of knee alignment and radiological assessment. The specific compartmental knee osteoarthritis is significantly correlated with the femoral offset which is statistically significant, the largest the offset the more likely the medial compartment to be affected. Conclusion and recommendations: The clinical assessment is good as radiological assessment. The femoral offset proved to be the most important determining factor for developing specific knee compartment osteoarthritis. No association was found between neck shaft angle, acetabulum to acetabulum distance and the affected side. Large multicenter genetic and anthropometric studies are needed to evaluate more the observed associations. Our results can be used to modify the current diagnostic and operative interventions for knee osteoarthritis.

Introduction: Joint involvement is a common extraintestinal manifestation of Crohn’s Disease (CD) that may require total knee arthroplasty (TKA). There is a paucity of evidence regarding the relationship between CD and postoperative outcomes after TKA surgery. This study seeks to evaluate the impact of CD on 90-day and >2-year follow-up postoperative outcomes of TKA patients. Methods: We retrospectively analyzed the Statewide Planning and Research Cooperative System database (2009-2013) and isolated ICD-9 codes for TKA patients (8154), while excluding those with any revision of knee replacements (0080–0084) and split into 2 groups with or without CD (5550–5559). Patient demographics and postoperative outcomes were compared. Logistic regression analyses with covariates (sex, race, Deyo score, age, and insurance) were utilized to evaluate the association of CD with 90-day and overall postoperative outcomes. Results: A total of 89,134 TKA patients were identified, 244 of whom had CD. Significant differences in age, race distribution, insurance, and Deyo score (all, p<0.05) were found. Multivariable analysis demonstrated CD was an independent risk factor for 90-day and overall medical complications, surgical complications, and readmission. Univariate and multivariable analyses report CD had significant increased rates and was a predictor, respectively, of overall blood transfusions (OR 1.51 [95% CI 1.14-2.00] p=0.004), acute renal failure (OR 1.65 [95% CI 1.05-2.60] p=0.031), and pulmonary embolism (OR 2.45 [95% CI 1.30-4.63] p=0.006). Conclusion: CD patients undergoing TKA have increased risk for renal and thromboembolic incidences and readmission. Preoperative medical optimization of CD may help to reduce or prevent these complications.

Introduction: There is growing evidence suggesting ulcerative colitis (UC) contributes to worse postoperative outcomes in patients undergoing joint operations. This study utilizes the New York State’s Statewide Planning and Research Cooperative System (SPARCS) database to investigate the impact that UC has on minimum 2-year follow-up postoperative outcomes of total knee arthroplasty (TKA) patients. Methods: The SPARCS database was retrospectively analyzed between the years 2009-2013. 92,627 TKA patients were isolated and split into two cohorts (UC status) with 1:1 propensity score matching based on age, gender, and obesity status (n=222 each, 444 total). Univariate analysis was used to compare demographics, hospital/operative variables, and postoperative outcomes between the two cohorts. Postoperative outcomes included surgical complications, medical complications, readmissions, reoperations, revisions of TKA, and mortality during hospitalization. Multivariate binary logistic regression controlling for age, sex, and obesity status was used to evaluate the significance of UC as a predictor on postoperative outcomes. Results: Both cohorts were comparable in terms of age, sex, obesity status, race, payment method, and Charlson-Deyo-Comorbidity-Index (all, p>0.05). The UC cohort had longer hospital stays (4.1 days vs. 3.6 days; p=0.027) and higher total surgical charges ($50,714 vs. $40,455; p=0.001). Patients with UC had higher rates of overall medical complications, sepsis, and in-hospital mortality (all, p<0.05). Conclusion: UC patients had higher surgical charges and hospital stays. In addition, UC is shown to be a significant predictor of overall medical complications, and sepsis in TKA patients. Orthopaedic surgeons should take UC into consideration for their patients undergoing TKA.

Introduction: There is a lack of literature that investigate iron deficiency anemia (IDA) as a potential risk factor for worse outcomes in patients undergoing total knee arthroplasty (TKA). This study seeks to evaluate the impact that IDA has on postoperative outcomes of patients who underwent TKA. Methods: The New York State’s Statewide Planning and Research Cooperative System database was retrospectively analyzed for ICD-9 codes between 2009–2013 for 92,627 primary TKA patients with minimum 2-year surveillance. 1:1 propensity score matching based on age, gender, and obesity status was then performed to split patients into two cohorts based on IDA status (n=1440 each, 2880 total). Demographic, perioperative, and postoperative variables (surgical complications, medical complications, readmissions, TKA revisions, reoperations, in-hospital mortality) were compared. Multivariate binary logistic regression analysis with covariates (age, gender, and obesity status) were used to determine IDA as an independent predictor of postoperative outcomes. Results: The two cohorts had comparable rates for age, gender, obesity status, race, payment method, and total surgical charges. The IDA cohort had longer total hospital stays than the non-IDA cohort (4.2 days vs. 3.8 days; p<0.001). Univariate and multivariate analysis showed that IDA patients had higher rates of overall surgical complications, transfusions of blood, overall medical complications, altered mental status, acute myocardial infarction (MI), acute renal failure, sepsis, and readmission (all, p<0.05). Conclusion: IDA patients undergoing TKA had longer hospital stays and higher rates of adverse postoperative outcomes. Surgeons should consider the impact of IDA on postoperative outcomes of patients undergoing TKA.