Patellar resurfacing in contemporary total knee arthroplasty: Frequency of complications in a matched cohort.

Introduction: Optimum patient selection and outcomes following patellar resurfacing are ongoing debates amongst the arthroplasty community. This study compared the outcomes of patients who had a total knee arthroplasty (TKA) with patellar resurfacing to those left with their native patella. Methods: A retrospective review of 1941 TKAs performed between 2016 and 2020 was conducted. 41 TKAs without patellar resurfacing and with 2-years of minimum follow-up were identified. Of these, 38 TKAs were matched on age (exact), sex (exact), and body mass index (±10) to 38 TKAs that had patellar resurfacing. The indications for patella resurfacing were subjective based upon the surgeon preference and assessment of cartilage quality. Paired t-tests and chi-square tests were used for analysis. Results: There was 1 major patellofemoral complication in both the resurfaced group (patellar fracture) and the non-resurfaced group (patellar tendon tear), requiring nonoperative management and revision surgery, respectively. However, in the non-resurfaced group there were 4 cases of subjective patellofemoral pain compared to none in the resurfaced group (p = 0.37). Additionally, 3 non-resurfaced patients required manipulation under anesthesia (MUA) compared to none in the resurfaced group (p = 0.44). Discussion: There was no difference in the frequency of major patella-specific complications between the groups. However, there was a non-statistically significant trend towards increased patellofemoral pain and MUA in the non-resurfaced group. Based on this study both methods of treatment remain viable options, but the trend towards increased pain and stiffness should continue to be closely evaluated.

An evaluation of the diagnostic performance of the triphasic bone scintigraphy in patients suspected of aseptic total knee arthroplasty loosening.

Background: Total Knee Arthroplasty (TKA) is a widely conducted and successful orthopedic procedure. However, aseptic loosening, a common cause of TKA failure, necessitates revision surgery. Diagnostic accuracy of triphasic bone scintigraphy, a common imaging modality for aseptic loosening detection, remains controversial. This study investigated the diagnostic accuracy of bone scintigraphy when separately evaluated by a nuclear physicist and an orthopedic surgeon, and the interrater reliability between the two. Methods: Patients undergoing knee revision surgery due to suspected aseptic loosening at three medical centers from 2006 to 2023 were included. Relevant demographic, clinical, and procedural data were extracted from the records. The bone scintigraphy results as noted by the nuclear physicist and orthopedic surgeon were used as index test and intraoperative findings of loosening were used as reference tests. Accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were calculated, and kappa's agreement was assessed. Results: Out of 611 revision TKAs, 59 cases were analyzed. The nuclear physicist's evaluation of bone scintigraphy had a sensitivity of 73 %, specificity of 0 %, positive predictive value of 93 %, negative predictive value of 0 %, and diagnostic accuracy of 69 %. The orthopedic surgeon's evaluation showed higher sensitivity, specificity, positive and negative predictive values, and an accuracy of 84 %. Agreement levels were moderate (kappa = 0.46) between the nuclear physicist's and orthopedic surgeons evaluation. Interpretation: The diagnostic accuracy of bone scintigraphy for aseptic loosening is 84 % when evaluated by the orthopedic surgeon compared to 69 % for the nuclear physicist's evaluation. Kappa's agreement between the two was moderate.

Quadriceps angle as an outcome measure for structural integrity following total knee arthroplasty in individuals with severe knee osteoarthritis.

Purpose: Total knee arthroplasty (TKA) is routinely performed for pain relief and to improve performance of the knee in individuals with severe knee osteoarthritis (OA). The quadriceps angle (Q-angle) is a key component of knee joint stability. However, there is a dearth of literature evaluating Q-angle as an outcome measure after TKA in individuals with severe knee OA. Objectives: The objective of the study was to assess the Q-angle as an outcome measure before and after TKA and to find the correlation of Q-angle with pain, quadriceps strength, and knee flexion range of motion (ROM) after TKA in individuals with severe knee OA. Methods: The Q-angles of 34 individuals (male: female = 17:17) were measured using standardized procedures. Pain, quadriceps strength, and knee flexion ROM were measured. The measurements were taken preoperatively (one day before surgery), and postoperatively at the sixth week and third month after TKA. Results: The mean Q-angle was 19.17° (SD = 1.92°) before TKA, 16.06° (SD = 1.87°) at the sixth week and 13.43° (SD = 1.77°) at the third month after TKA. Significant linear correlations were noted between the Q-angle and pain, quadriceps strength, and knee flexion ROM following TKA. Conclusion: The Q-angle was measured before and after TKA using a standardized clinical goniometric method. Understanding the Q-angle before and after TKA and its relationship with various clinical and functional variables is imperative in clinical practice for orthopedic surgeons and rehabilitation professionals.

Geographical incidence of testosterone supplementation in total hip and knee arthroplasty.

Introduction: Prescription testosterone usage in the United States declined after 2013 following reports of its association with myocardial infarction and stroke. However, more recently there has been a documented increase in testosterone prescriptions. Recently, testosterone levels have also been hypothesized to increase infection risk in patients undergoing elective shoulder arthroplasty. Furthermore, testosterone may increase the risk of venous thromboembolism. These complications are perioperative concerns for total hip and knee arthroplasties (THA/TKA). Therefore, the purpose of our study is to identify trends in the incidence of testosterone prescriptions in patients who underwent THA/TKA with respect to geographical population data. Methods: We retrospectively reviewed 40,711 primary THAs and 50,893 primary TKAs performed in males between 1/1/2016 and 12/31/2021 using a commercial claims database. Records were reviewed for demographics, geographical location, and supplemental testosterone prescriptions within 1 year prior to surgery. Patient Metropolitan Statistical Area (MSA) was assessed with respect to United States Census Population Data. Results: We identified 91,604 males who underwent primary THA (n = 40,711) or TKA (n = 50,893). For THA/TKA, patients who were younger had a higher likelihood of having a supplemental testosterone prescription (OR = 0.99, 95 % CI [0.99-1.00], p < 0.001). TKA patients (2,507, 4.9 %) had a higher rate of testosterone prescriptions than THA patients overall (1,413, 3.4 %), (OR = 1.44 95 % CI [1.35, 1.54], p < 0.001) as well as within each year.For THA and TKA patients, patients in the Midwest (OR = 1.61, p < 0.001), South (OR = 3.04, p < 0.001), and West (OR = 2.28, p < 0.001) regions all had higher testosterone prescription rates than the Northeast. Patients living in a city (MSA population ≥200,000) were more likely to be prescribed testosterone (OR = 1.20, p = 0.002). Conclusion: Surgeons conducting TKA/THA should be aware that younger patients, those in higher population areas, and those in the Midwest, South, and West regions are more likely to be prescribed testosterone than those in the Northeast.

Gender, BMI, and Age-Related Variations in Lower Limb Alignment Parameters and CPAK Phenotypes in Chinese Patients with Knee Osteoarthritis.

OBJECTIVES: Research on the distribution of and the variation in coronal plane alignment of the knee (CPAK) in the Chinese osteoarthritis population is limited. We aimed to establish the CPAK classification based on the characteristics of lower limb alignment in the Chinese osteoarthritis population. We also investigated variations in lower limb alignment parameters and CPAK phenotypes based on gender, body mass index (BMI), and age. METHODS: A retrospective study was conducted on a total of 944 knees diagnosed with osteoarthritis in 479 patients from January 2017 to December 2023. A scatterplot was used to describe the distribution of the CPAK classification, and the differences in lower limb alignment parameters and the CPAK classification were compared across genders (male, female), ages (middle-aged/<65 years, elderly/≥65 years), and BMI categories (normal/<25 kg/m2, overweight and obese/≥25 kg/m2) using the chi-squared test or Fisher's exact test. RESULTS: The average arithmetic hip-knee-ankle angle and joint line obliquity (JLO) were -3.03° ± 5.69° and 174.45° ± 4.29°, respectively. There was a higher prevalence of constitutional varus alignment in males and the overweight or obese group, while constitutional valgus alignment was more common in females and the normal BMI group (p < 0.05). Additionally, females had a greater apex distal JLO than males (p < 0.05). There were no statistically significant differences in lower limb alignment parameters among different age groups (p > 0.05). Although there were variations in alignment parameters across different genders and BMI categories in the knee osteoarthritis population, the predominant CPAK classifications were type I (38.03%), followed by type II (20.02%) and type IV (17.06%). CONCLUSION: The most common CPAK types were I, II, and IV, and they were not influenced by gender, BMI, or age, indicating that the CPAK classification can reliably reflect constitutional alignment. A better understanding of native alignment variability can aid in providing patient-specific recommendations when considering orthopedic alignment strategies.

Revision ACL reconstruction, but not bilateral ACL reconstruction, is associated with clinically relevant inferior subjective knee function compared with primary ACL reconstruction: A comparative analysis of 6831 patients.

PURPOSE: To evaluate and compare the subjective knee function in patients undergoing revision and bilateral anterior cruciate ligament (ACL) reconstruction (ACLR) with those undergoing primary ACLR in a large cohort. METHODS: Patients without concomitant ligament injuries who underwent primary, revision or bilateral ACLR at the Capio Artro Clinic, Stockholm, Sweden, between 2005 and 2018 were identified. The Knee injury and Osteoarthritis Outcome Score (KOOS) was collected preoperatively and at 1, 2 and 5 years postoperatively from the Swedish National Knee Ligament Registry. Patients who underwent revision and bilateral ACLR were compared with those who underwent primary ACLR (control group) using Student's t test. RESULTS: A total of 6831 patients (6102 with primary ACLRs, 343 with revision ACLRs and 386 with bilateral ACLRs) were included. Preoperatively, there were significant but nonclinically relevant differences in favour of the revision ACLR group for KOOS Symptoms, Pain, Activities of Daily Living (ADL) and Sport/Rec subscale scores compared with the primary ACLR group. Postoperatively, except for the 1-year Symptoms and ADL subscales, the revision ACLR group reported significantly lower scores on all KOOS subscales than the primary ACLR group, with clinically relevant differences (>8-10 points) for the 1-, 2- and 5-year Sport/Rec and Quality of Life (QOL) subscales. The bilateral ACLR group reported significantly, but not clinically relevant, inferior scores on the 1-year Symptoms and QOL subscales and the 5-year Sport/Rec and QOL subscales compared with the primary ACLR group. CONCLUSIONS: Revision ACLR, but not bilateral ACLR, was associated with clinically relevant inferior subjective knee function compared with primary ACLR. It is important to counsel patients regarding their future subjective knee function after repeated ACLR. Compared to primary ACLR, inferior subjective results should be expected after revision ACLR, but not after bilateral ACLR. LEVEL OF EVIDENCE: Level III.

A radiographic artificial intelligence tool to identify candidates suitable for partial knee arthroplasty.

INTRODUCTION: Knee osteoarthritis is a prevalent condition frequently necessitating knee replacement surgery, with demand projected to rise substantially. Partial knee arthroplasty (PKA) offers advantages over total knee arthroplasty (TKA), yet its utilisation remains low despite guidance recommending consideration alongside TKA in shared decision making. Radiographic decision aids exist but are underutilised due to clinician time constraints. MATERIALS AND METHODS: This research develops a novel radiographic artificial intelligence (AI) tool using a dataset of knee radiographs and a panel of expert orthopaedic surgeons' assessments. Six AI models were trained to identify PKA candidacy. RESULTS: 1241 labelled four-view radiograph series were included. Models achieved statistically significant accuracies above random assignment, with EfficientNet-ES demonstrating the highest performance (AUC 95%, F1 score 83% and accuracy 80%). CONCLUSIONS: The AI decision tool shows promise in identifying PKA candidates, potentially addressing underutilisation of this procedure. Its integration into clinical practice could enhance shared decision making and improve patient outcomes. Further validation and implementation studies are warranted to assess real-world utility and impact.

Identifying high-risk groups for deep vein thrombosis after primary total knee arthroplasty using preoperative Caprini scores and D-dimer levels.

BACKGROUND: Caprini score and D-dimer are well-recognized markers in deep vein thrombosis (DVT) assessment. However, their utility in guiding post-arthroplasty DVT risk is hampered by susceptibility to various post-operative factors, limiting their effectiveness as reminders. Conversely, these markers exhibit greater stability in the pre-operative setting. Despite this, research on the pre-operative predictive value of Caprini score and D-dimer for DVT following primary total knee arthroplasty (TKA) remains scarce. METHODS: In a retrospective study, we analyzed data from patients who underwent primary TKA, between August 2015 and December 2022. Upon admission, Caprini scores were assessed, and comprehensive blood panels were obtained from fasting blood samples. For all patients, lower limb vascular Doppler ultrasonography was performed pre-operatively to exclude those with pre-existing DVT, and all patients underwent DVT examination again post-operatively. RESULTS: Our study included 2,873 patients, averaging 67.98 ± 7.54years, including 676 men and 2,197 women. In this study, 303 (10.55%) patients developed postoperative DVT, and 57 (1.98%) cases presented with lower limb symptoms. DVT incidence in patients with pre-operative Caprini scores of 1-2 (6.50%), 3 (10.28%), and ≥ 4 (18.05%) showed significant differences (P < 0.05). DVT rates were 14.80% in patients with pre-operative D-dimer levels of ≥ 1 mg/L, higher than the 8.98% in those with levels of < 0.5 mg/L, and 10.61% in those with levels 0.5-1 mg/L (P < 0.05). In patients with Caprini scores of 1-2 and D-dimer levels ≤ 0.5 mg/L, the occurrence rate of postoperative DVT was only 5.84%. For patients with Caprini scores ≥ 4 and D-dimer levels ≥ 1.0 mg/L, the postoperative DVT occurrence rate soared to 24.81%, with the OR(odds ratio) was 4.744 compared to the former group. CONCLUSION: Patients with preoperative higher Caprini scores and D-dimer are more likely to develop DVT after TKA. Additionally, those with a preoperative Caprini score ≥ 4 and D-dimer level ≥ 1.0 mg/L have a significantly increased risk (24.81%) of developing DVT, identifying them as a high-risk group for DVT following TKA. These findings hold significant value for DVT risk stratification in primary TKA patients and the formulation of preoperative interventions to mitigate the risk of DVT.

The Child Opportunity Index and Outcomes After Pediatric Anterior Cruciate Ligament Reconstruction.

Background: Research at the intersection between social determinants of health (SDOH) and orthopaedics remains an area of active exploration, with recent literature demonstrating significant disparities in a wide array of orthopaedic outcomes in patients with different SDOH. Purpose/Hypothesis: The purpose of this study was to use a validated composite measure of SDOH mapped to census tracts (Child Opportunity Index [COI]) to explore disparities in functional outcomes after anterior cruciate ligament (ACL) reconstruction. It was hypothesized that patients with a lower COI score would have delayed surgical care and worse functional outcomes after ACL reconstruction. Study Design: Cohort study; Level of evidence, 3. Methods: Demographic, surgical, and functional outcomes data were extracted for all patients aged ≤18 years who underwent primary ACL reconstruction at our institution between 2009 and 2019. Strength deficits were calculated, and COI quintile scores were obtained. One-way analysis of variance, the chi-square test, and the Fisher exact test were used to compare variables of interest between the lower 2 quintiles (low group) and the upper 2 quintiles (high group). Results: Of the 1027 patients, 226 (22.0%) were in the low group, while 801 (78.0%) were in the high group. There was a significantly greater time from injury to surgery in the low group than in the high group (98.15 ± 102.65 vs 71.79 ± 101.88 days, respectively; P < .001). The low group had a significantly lower extension-flexion range of motion at 1- and 3-month follow-up (P = .03 and P = .02, respectively) but no difference at 6-month follow-up (P = .27). The low group attended fewer physical therapy visits than the high group (24.82 ± 10.55 vs 37.81 ± 18.07, respectively; P < .001). The low group had significant deficits in quadriceps strength at 3, 6, and 9 months at 180 deg/s (P = .03, P < .001, and P = .01, respectively) and at 6 months at 300 deg/s (P = .002). Conclusion: In this study, we found that the COI was associated with disparities in key clinical outcomes including time to surgery, postoperative range of motion, and postoperative strength.

Patient Engagement in a Mobile App-Based Rehabilitation Program for Total Hip or Knee Arthroplasty: Secondary Data Analysis of a Randomized Controlled Trial.

BACKGROUND: Health care professionals use mobile apps to support patients' rehabilitation after total hip or knee arthroplasty. Understanding patient engagement in such mobile health interventions can help tailor these interventions to better support patients. OBJECTIVE: This study aimed to investigate patient engagement in a mobile app-based arthroplasty rehabilitation program and to investigate the association between patient engagement and their characteristics. METHODS: Data were extracted from a pool of 42 participants in the experimental arm of a randomized controlled trial that used a mobile app (WeChat [Tencent Holdings Limited])-based program to support patients' rehabilitation after total hip or knee arthroplasty. The primary outcomes were the number of days the participants accessed the program and completed recommended rehabilitation tasks. Secondary outcomes included data on the participants' posts on a discussion forum, messages sent by the participants, access to the program components, and reading and sharing the program content. Generalized linear models were used to analyze the association between patient engagement and personal characteristics. RESULTS: The participants reported in a rehabilitation diary accessing the program on a mean of 5.2 (SD 2) days per week and completing recommended rehabilitation tasks on a mean of 6.5 (SD 0.8) days per week. The majority (31/42, 74%) posted on the discussion forum, with a mean of 18.1 (SD 21.2) posts. Most participants (37/42, 88%) sent messages to health care professionals, with a mean of 14 (SD 15.9) messages. The program components were visited for a total of 525 times. The program content was read 898 times and shared 82 times in total. Generalized linear models showed that both primary outcomes, the number of days the participants accessed the program (B=6.46, 95% CI 1.98-15.35; χ21=11.1, P=.001) and the number of days they completed rehabilitation tasks (B=2.65, 95% CI 0.45-5.48; χ21=5.7, P=.02), were positively associated with having a high school education or above. In addition, the number of posts on the discussion forum was positively associated with living with family, having a high school education or above, undergoing total knee arthroplasty, having comorbidities, and the score of self-efficacy but was negatively associated with age. The number of messages sent by the participants was positively associated with having a high school education or above, having comorbidities, and the score of self-efficacy. CONCLUSIONS: Patient engagement in mobile arthroplasty rehabilitation is associated with their education level, cohabitation status, age, type of surgery, presence of comorbidities, and sense of self-efficacy. Program developers can consider these characteristics and use strategies, such as family involvement, in the design of mobile arthroplasty rehabilitation programs to enhance patient engagement in such interventions. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12621000867897; https://tinyurl.com/mtdw25fp.

Reconstructive surgery for gunshot injuries of the knee: experience from the Russo-Ukranian War 2022-2024.

The invasion of Ukraine by the Russian Federation in February 2022 has witnessed the first peer-on-peer full-scale European conflict since World War 2. We have noted that the vast majority of injuries affect the extremities. Within that group, injuries to the joints pose a huge clinical challenge. Specifically, 17.1% of all gunshot injuries (GSWs) involved the joints, which represents 22.3% of all limb injuries. 55.6% of all GSW to the joints involved the knee; 10% had a concomitant vascular injury and 15%-20% had a nerve injury.The surgical management of ballistic knee injuries includes initial damage control surgery with debridement of non-vitalised tissue, vascular reconstruction and fasciotomies where necessary, with stabilisation of bone injury with a spanning external fixator. Following repatriation to Role 4 facilities, staged reconstruction is performed with cement spacers followed by autograft, endoprosthesis or arthrodesis. Where reconstruction is not possible, above-knee amputation remains an option.In this paper, based on the analysis of 33 cases, we describe the Ukrainian early experience of the management of gunshot wounds to the knee joint with three clinical case studies as representative examples.

Failure and complication rates following meniscal all-inside and inside-out repairs: A systematic review and meta-analysis.

PURPOSE: This study examines failure rates, complication rates and patient-reported outcome measures (PROMs) for meniscal all-inside (AI) and inside-out (IO) repair techniques. METHODS: A systematic search was conducted on PubMed, Embase and Cochrane (inception to January 2024) assessing for Level I-III studies evaluating outcomes after meniscal repair. The primary outcome regarded differences in failure rates between AI and IO repair techniques. Secondary outcomes included a comparison of complication rates and PROMs. Quality assessment was performed using the Grading of Recommendations Assessment, Development and Evaluation and Methodological Index for Non-Randomized Studies criteria. A meta-analysis was conducted for outcomes reported by more than three comparative studies. RESULTS: A total of 24 studies (13 studies and 912 menisci for AI vs. 17 studies and 1,117 menisci for IO) were included. The mean follow-up ranges were 22-192 months (AI) and 18.5-155 months (IO). The overall reported AI failure rate ranged from 5% to 35% compared to 0% to 25% within the IO group. When comparing meniscal repair failure rates in the setting of concomitant anterior cruciate ligament reconstruction, the AI group had a failure rate (AI: 5%-34%; IO: 0%-12.9%). The complication rate ranged from 0% to 40% for AI and 0% to 20.5% for IO. Post-operative PROM scores ranged from 81.2 to 93.8 (AI) versus 89.6 to 94 (IO) for IKDC and 4.0-7.02 (AI) versus 4.0-8.0 (IO) for Tegner. Upon pooling of six comparative studies, a significantly lower failure rate favouring the IO technique was observed (15.9% AI vs. 11.1% IO; p = 0.02), although this result was influenced by a study with a predominantly elite athlete population. Moreover, no significant differences were found regarding complication rates between cohorts (7.3% AI vs. 4.8% IO; p = 0.86). CONCLUSION: The present study underscores comparable clinical success between AI and IO meniscal repair techniques, with both techniques demonstrating similar complication rates. However, the AI repair technique was associated with 1.77 times higher odds of failure compared to the IO cohort. LEVEL OF EVIDENCE: Level III.

[Improving the Accuracy of Patient Self-Care After Joint Replacement Surgery].

BACKGROUND & PROBLEMS: Joint replacement wound stitches are typically not removed until two weeks after the operation. Therefore, patients with joint replacement must be able to execute proper wound care after discharge from the hospital to reduce the risk of wound infection. Prior data from Chang Gung Memorial Hospital's orthopedics ward indicate only 69% of joint-replacement patients are able to perform wound care properly at home. Potential causes for this noted by patients include age-related forgetfulness, being unable to discern redness or swelling in the wound, and language comprehension difficulties (i.e., Taiwanese vs. Mandarin). Poor rates of wound care may also be attributable to incomplete wound care education by nursing staff and wound care education being provided without adequate practice on the day of patient discharge. PURPOSE: This project was implemented to improve the accuracy of wound self-care performed by patients after joint replacement surgery and to enhance their related knowledge and wound-care technical correctness. RESOLUTION: A wound care education checklist, wound care cue cards, wound care video clips, wound condition red flag cue cards, and customized wound care pack were proposed and implemented. RESULTS: The rate of accuracy of wound self-care performance increased from 69% pretest to 98% posttest, showing the intervention to have effectively improved post-discharge wound care quality. CONCLUSIONS: To effectively improve the post-discharge accuracy of wound self-care in patients with joint replacement, the consistency of post-surgery wound care education given by nursing staff to patients should be improved, patients should be reminded of wound assessment and care steps, and patients should be aware that wound abnormalities require an immediate return to the hospital for follow-up treatment.

Effects of combining rehabilitation training on the recovery of athletic ability after reconstruction of injured ligament.

This paper aims to investigate the impact of conventional rehabilitation training and neuromuscular electrical stimulation (NMES) on the recovery of motor abilities in patients following ligament injury reconstruction. Forty postoperative patients who underwent surgery for anterior cruciate ligament reconstruction (ACLR) were randomly allocated to either the conventional rehabilitation group or the NMES group. The NMES group received NMES treatment in addition to the conventional rehabilitation program starting from eight weeks postoperatively. Various parameters, including knee joint function, stability, and balance, were compared between the two groups at eight weeks and 12 weeks postoperatively. Compared to the data at eight weeks postoperatively, both groups exhibited significant improvements in all measured indicators at 12 weeks postoperatively (p < 0.05). In the 12th week after the surgery, the NMES group demonstrated a Lysholm score of 93.18 ± 3.67 points, an IKDC score of 84.65 ± 2.33 points, a KT-2000 measurement of 0.88 ± 0.45 mm, a thigh circumference difference of -1.33 ± 0.55 cm, a knee flexion angle of 130.12 ± 4.21°, a single-leg standing time of 60.12 ± 9.33 s, a YBT score of 70.26 ± 2.68 points, and a Bulgarian split squat 1RM size of 58.07 ± 6.85 kg; all of these results were significantly superior to those observed in the conventional group (p < 0.05). NMES significantly enhances the recovery of athletic ability in patients following postoperative ACLR and can be effectively applied in clinical practice.

Unexpected positive cultures in conversion hip and knee arthroplasty.

PURPOSE: Total hip and knee arthroplasty in patients with previous history of periarticular surgery, such as osteosynthesis, can be surprisingly complex. This type of procedure is known as conversion arthroplasty (cTHA or cTKA) and has a higher risk of complications. The rates of unexpected positive cultures (UPC) and the risk of periprosthetic joint infection (PJI) compared to primary arthroplasty is unclear. The main purpose of this study was to evaluate rates of Unexpected Positive Cultures (UPC) in a series of conversion arthroplasty patients. The main questions to answer are: 1. Are the patients with conversion arthroplasties more susceptible to UPC than other causes of revision arthroplasties? 2. Are the conversion patients with UPC more susceptible to developing PJI? METHODS: This was a retrospective review of patients submitted to cTHA and cTKA from January 2012 to September 2018. Patients with history of previous infection or with missing intraoperative cultures were excluded. The UPC was defined as a single positive culture obtained during a procedure previously considered aseptic and PJI was defined according to the 2018 ICM criteria. After excluding 141 cases, 205 patients were analyzed, 160 hips and 45 knees. RESULTS: Nine (4.4%) UPC were identified, five (3.1%) in the hip group and four (8,9%) in the knee group. Staphylococcal species were the most common isolated bacteria (n = 7, 77.7%). During the study period, four (1,9%) patients were diagnosed with PJI. Only one case had an UPC and a different germ was identified during revision arthroplasty workup. CONCLUSIONS: While UPC are more prevalent in conversion knee arthroplasties compared to conversion hip arthroplasties, the rates are similar to those observed in revision arthroplasty for other indications. Importantly, the presence of a UPC in conversion arthroplasty does not appear to elevate the risk of subsequent periprosthetic joint infection, provided a thorough PJI workup has been conducted preoperatively. Therefore, in such cases, UPCs may be safely disregarded.

The Effectiveness of Temporary Hemiepiphysiodesis for Non-idiopathic Coronal Angular Deformity of the Knee in Children: A Comparison of Hinge Eight-Plate and Traditional Eight-Plate.

OBJECTIVE: Temporary hemiepiphysiodesis (TH) is a very common technique for coronal angular deformity of the knee in children, especially non-idiopathic. However, there is currently a dearth of comparative research on the hinge eight-plate (HEP) and traditional eight-plate (TEP). This study aimed to assess the clinical effectiveness and implant-related complication rates of TH using TEP and HEP for non-idiopathic coronal angular deformity, as well as to identify clinical factors affecting correction velocity. METHODS: We retrospectively observed a consecutive series of patients with non-idiopathic coronal angular deformity of the knee who underwent TH using HEP or TEP and completed the deformity correction process from July 2016 to July 2022. According to the kind of eight plates, we divided those patients into the HEP group and the TEP treatment group. Relevant clinical factors, including the mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibial angle (mMPTA), screw divergence angle (SDA), angle of plate and screw (APS), hinge angle of HEP (HA), and the knee zone location of the lower extremity mechanical axis, were documented. Additionally, deformity correction velocity, complications, and clinical efficacy were assessed. Categorical variables were analyzed using the chi-squared test, Fisher exact test, or Wilcoxon test, while continuous variables were evaluated using the t-test or analysis of variance (ANOVA). RESULTS: There were 29 patients in the HEP treatment group (seven girls and 22 boys) and 33 patients (12 girls and 21 boys) in the TEP treatment group. In all, 91.86% (79/86 knees) of the genu angular deformities were completely corrected, 6.98% (6/86 knees) had the overcorrection condition, and 10.47% (9/86 knees) had screw loosening. The swayback HEP rate was 11.29% (7/62 HEPs), which was related to the screw loosening in the HEP group (p < 0.001). The overall correction velocities and screw divergence angle change speeds in the HEP group were all significantly faster than those in the TEP group (p < 0.05). The initial APS of the HEP implanted was higher than that of TEP (p < 0.01), and multisite changes of APS during deformity correction of the HEP group were smaller than that of the TEP group. CONCLUSION: HEP proved to be an appropriate device for TH for non-idiopathic coronal angular deformities of the knee with high correction velocity in children. Avoiding the occurrence of the swayback phenomenon may reduce the complications of HEP.

Incidence of and risk factors for preoperative deep vein thrombosis in elderly patients with end-stage osteoarthritis following total knee arthroplasty: a retrospective cohort study.

BACKGROUND: Deep vein thrombosis (DVT) is a common and serious risk in elderly patients with knee osteoarthritis (OA), making preoperative detection crucial. Despite this, identifying OA patients at high risk for preoperative DVT and appropriately targeting them for venous ultrasound screening remains a challenge. There is limited research-based evidence on the risk factors for preoperative DVT in elderly patients with end-stage OA. We examined the incidence of and risk factors for preoperative DVT in elderly patients with end-stage OA scheduled for total knee arthroplasty. METHODS: We retrospectively analyzed the demographic data (age, sex, body mass index, current smoking, alcohol consumption, walking status, and Barthel index score), medical history, and laboratory test indices of 1411 patients with end-stage OA aged ≥ 60 years scheduled for total knee arthroplasty from January 2015 to December 2018. Risk factors for preoperative DVT were evaluated by univariate and multivariate logistic analyses. Receiver operating characteristic analysis was performed to determine optimal cut-off values. RESULTS: The incidence of preoperative DVT was 4.5% (63 of 1411 patients). Seven independent risk factors were correlated with preoperative DVT in the multivariate logistic regression: age (odds ratio [OR], 1.073; P = 0.002), D-dimer concentration (OR, 1.173; P = 0.003), hyperlipidemia (OR, 2.038; P = 0.045), atrial fibrillation (OR, 4.004; P = 0.033), chronic renal failure (OR, 6.732; P = 0.008), chronic obstructive pulmonary disease (COPD) (OR, 8.721; P = 0.001), and walking status (wheelchair) (OR, 2.697; P = 0.002). The optimal cut-off values for predicting preoperative DVT were 0.585 µg/mL for the D-dimer concentration (area under the curve [AUC], 0.769; P < 0.001) and 72.5 years for age (AUC, 0.668; P < 0.001). CONCLUSION: Among elderly patients with end-stage OA, venous ultrasonography to rule out DVT risk should be prioritized in those with a high D-dimer concentration (> 0.585 µg/mL), high age (> 72.5 years), hyperlipidemia, atrial fibrillation, chronic renal failure, COPD, and walking status (wheelchair).

High expression of transcription factor EGR1 is associated with postoperative muscle atrophy in patients with knee osteoarthritis undergoing total knee arthroplasty.

BACKGROUND: Muscle atrophy is a typical affliction in patients affected by knee Osteoarthritis (KOA). This study aimed to examine the potential pathogenesis and biomarkers that coalesce to induce muscle atrophy, primarily through the utilization of bioinformatics analysis. METHODS: Two distinct public datasets of osteoarthritis and muscle atrophy (GSE82107 and GSE205431) were subjected to differential gene expression analysis and gene set enrichment analysis (GSEA) to probe for common differentially expressed genes (DEGs) and conduct transcription factor (TF) enrichment analysis from such genes. Venn diagrams were used to identify the target TF, followed by the construction of a protein-protein interaction (PPI) network of the common DEGs governed by the target TF. Hub genes were determined through the CytoHubba plug-in whilst their biological functions were assessed using GSEA analysis in the GTEx database. To validate the study, reverse transcriptase real-time quantitative polymerase chain reaction (qRT-PCR), enzyme-linked immunosorbent assay (ELISA), and Flow Cytometry techniques were employed. RESULTS: A total of 138 common DEGs of osteoarthritis and muscle atrophy were identified, with 16 TFs exhibiting notable expression patterns in both datasets. Venn diagram analysis identified early growth response gene-1 (EGR1) as the target TF, enriched in critical pathways such as epithelial mesenchymal transition, tumor necrosis factor-alpha signaling NF-κB, and inflammatory response. PPI analysis revealed five hub genes, including EGR1, FOS, FOSB, KLF2, and JUNB. The reliability of EGR1 was confirmed by validation testing, corroborating bioinformatics analysis trends. CONCLUSIONS: EGR1, FOS, FOSB, KLF2, and JUNB are intricately involved in muscle atrophy development. High EGR1 expression directly regulated these hub genes, significantly influencing postoperative muscle atrophy progression in KOA patients.

Functional Outcome in Obese Patients Undergoing Image-Based Cruciate Retaining Robotic-Assisted Total Knee Arthroplasty Using the Subvastus Approach: A Short-Term Study.

Introduction Knee osteoarthritis (OA) is a prevalent degenerative joint disease that significantly affects quality of life, especially among obese and morbidly obese individuals. Total knee arthroplasty (TKA) is an effective treatment for end-stage OA, but it presents unique challenges in obese patients. The mini-subvastus approach (SA) and robotic-assisted TKA (RA-TKA) are emerging techniques that may address these challenges. This study evaluates the clinical and radiological outcomes of cruciate-retaining (CR) RA-TKA using the mini-subvastus approach in obese and morbidly obese patients. Methods This study included 114 obese patients (215 knees) with primary OA who underwent CR RA-TKA (Maxx Meril CR knee, USA) using the Cuvis Joint® robotic system. Patients had a BMI of ≥30 kg/m² (n=101) and morbid obesity with a BMI ≥40 kg/m² (n=13). Preoperative planning involved CT scans and the J-planner for optimal implant size and positioning. Surgery was performed without tourniquets, and patients were mobilized postoperatively. Clinical outcomes were assessed using visual analog scale (VAS) scores and the American Knee Society Score (AKSS) at three and six months. Results The study included 85 females and 29 males with an average age of 61.8 years. Satisfactory knee exposure was achieved in all cases using SA, with no major complications such as wound infections, deep vein thrombosis, or component misalignment. Intraoperative challenges were managed effectively, including two cases of medial collateral ligament avulsion and one partial patellar tendon avulsion. Postoperative VAS scores showed significant pain reduction from pre-op (6.54) to post-op day 3 (1.3). AKSS improved from a pre-op average of 33.9 to 70.7 at three months and 80.9 at six months. Most patients (80%) achieved exceptional range of motion (ROM) ≥120° at six months. Discussion The mini-subvastus approach in RA-TKA offers several advantages, including reduced postoperative pain, faster recovery, and improved quadriceps strength, even in obese patients. The use of robotic assistance ensures accurate component positioning and alignment, mitigating the challenges typically associated with obese patients undergoing TKA. Conclusion The study demonstrates the feasibility and effectiveness of CR RA-TKA using the mini-subvastus approach in obese and morbidly obese patients. This technique provides adequate exposure, reduces pain, and promotes early mobilization and recovery with satisfactory clinical and radiological outcomes. The findings support the potential for wider adoption of this approach in managing knee OA in obese populations, though further studies with longer follow-up are warranted.

Rate and Timing of Revision and Contralateral Anterior Cruciate Ligament Reconstruction Relative to Index Surgery.

Background: After anterior cruciate ligament (ACL) reconstruction (ACLR), ipsilateral ACL graft reinjury or contralateral ACL injury has been reported. The rate and predictors of such subsequent ACL injuries have not been reported in recent years and in large patient cohorts. Purpose: The current study utilized a large, national, multi-insurance, administrative database to assess subsequent ACLR and factors associated with its occurrence. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Using the PearlDiver M151 database, patients who underwent ACLR within the United States between 2015 and 2021 were abstracted. All included patients had ≥3 years of evaluation after initial ACLR. Patients who underwent a subsequent reconstruction (ipsilateral or contralateral) within 3 years were determined and the timing assessed. Using univariable and multivariable logistic regression, the factors associated with having a subsequent ACLR and the factors associated with returning for ipsilateral versus contralateral ACLR were examined. Results: In total, 40,151 patients who underwent initial ACLR during the study period were identified. Of these, subsequent ACLR was performed for 1689 patients (4.2%). These included ipsilateral revision for 1018 (60.3%) and contralateral reconstruction for 671 (39.7%) patients. Patients returning for ipsilateral reconstruction did so sooner than patients needing a contralateral reconstruction. On multivariable analysis, the only factor independently associated with subsequent ACLR was younger age (odds ratio [OR] = 4.17 for 10-14 years relative to 25-29 years; P < .0001). Factors associated with returning for an ipsilateral revision ACLR as opposed to contralateral ACLR were earlier revision (OR = 1.49 within 1.5 years relative to after 1.5 years; P = .0001) and female sex (OR = 0.62 relative to male sex; P < .0001). Conclusion: The overall rate of requiring a subsequent ACLR was found to be 4.2%, with 60.3% of these being to the ipsilateral ACL. This information may be helpful for evolving injury-prevention programs and patient counseling.