Demonstrating antibiotic stewardship while diagnosing and treating bilateral pseudoseptic arthritis: a case report.

INTRODUCTION: Although viscosupplementation is a commonly used treatment for osteoarthritis and is widely regarded as a safe treatment option, it is associated with the rare complication of pseudoseptic arthritis. Most existing case reports that cite this rare complication employed the use of early broad-spectrum antibiotics. CASE PRESENTATION: In this case report, we present a 61-year-old African American female patient who presented with bilateral knee pseudoseptic arthritis in the setting of viscosupplementation. She presented 3 days after bilateral viscosupplementation injections with bilateral knee swelling, discomfort, and pain with micromotion. Her white blood cell count (WBC) was 12.83 (4.5-11 normal), her C-reactive protein (CRP) level was 159 mg/L (0-10 normal), and her erythrocyte sedimentation rate (ESR) was 79 mm/hour (0-40 normal). Her left knee aspirate yielded 38,580 WBC with a negative gram stain and negative cultures. Her right knee aspirate yielded 29,670 WBC with a negative gram stain and negative cultures. Through the utilization of careful clinical monitoring, ice therapy, and non-steroidal inflammatory medication, we were able to successfully treat this patient while maintaining proper antibiotic stewardship. CONCLUSION: Pseudoseptic arthritis in the setting of viscosupplementation can be adequately treated and monitored without the use of antibiotics.

Analysis of cartilage loading and injury correlation in knee varus deformity.

Knee varus (KV) deformity leads to abnormal forces in the different compartments of the joint cavity and abnormal mechanical loading thus leading to knee osteoarthritis (KOA). This study used computer-aided design to create 3-dimensional simulation models of KOA with varying varus angles to analyze stress distribution within the knee joint cavity using finite element analysis for different varus KOA models and to compare intra-articular loads among these models. Additionally, we developed a cartilage loading model of static KV deformity to correlate with dynamic clinical cases of cartilage injury. Different KV angle models were accurately simulated with computer-aided design, and the KV angles were divided into (0°, 3°, 6°, 9°, 12°, 15°, and 18°) 7 knee models, and then processed with finite element software, and the Von-Mises stress distribution and peak values of the cartilage of the femoral condyles, medial tibial plateau, and lateral plateau were obtained by simulating the human body weight in axial loading while performing the static extension position. Finally, intraoperative endoscopy visualization of cartilage injuries in clinical cases corresponding to KV deformity subgroups was combined to find cartilage loading and injury correlations. With increasing varus angle, there was a significant increase in lower limb mechanical axial inward excursion and peak Von-Mises stress in the medial interstitial compartment. Analysis of patients' clinical data demonstrated a significant correlation between varus deformity angle and cartilage damage in the knee, medial plateau, and patellofemoral intercompartment. Larger varus deformity angles could be associated with higher medial cartilage stress loads and increased cartilage damage in the corresponding peak stress area. When the varus angle exceeds 6°, there is an increased risk of cartilage damage, emphasizing the importance of early surgical correction to prevent further deformity and restore knee function.

Cross-cultural adaption, validity, and reliability of the Japanese version of the Central Aspects of Pain in the Knee (CAP-Knee-J) questionnaire in patients with knee pain: a validation study.

BACKGROUND: Knee pain is a prominent concern among older individuals, influenced by the central nervous system. This study aimed to translate the Central Aspects of Pain in the Knee (CAP-Knee) questionnaire into Japanese and investigate its reliability and validity in older Japanese individuals with knee pain. METHODS: Using a forward-backward method, CAP-Knee was translated into Japanese, and data from 110 patients at an orthopedic clinic were analyzed. The Japanese version (CAP-Knee-J) was evaluated regarding pain intensity during walking, central sensitization inventory, and pain catastrophizing scale. Statistical analyses confirmed internal validity and test-retest reliability. Concurrent validity was assessed through a single correlation analysis between CAP-Knee-J and the aforementioned measures. Exploratory factor analysis was employed on each CAP-Knee-J item to examine structural validity. RESULTS: CAP-Knee-J showed good internal consistency (Cronbach's α = 0.86) and excellent test-retest reliability (intraclass correlation coefficient = 0.77). It correlated significantly with pain intensity while walking, central sensitization inventory scores, and pain catastrophizing scale scores. Exploratory factor analysis produced a three-factor model. CONCLUSIONS: CAP-Knee-J is a reliable and valid questionnaire for assessing central pain mechanisms specific to knee pain in older Japanese individuals, with moderate correlations with the CSI and weak with the PCS, thus indicating construct validity. This study supports the development of effective knee pain treatments and prognosis predictions.

Left knee septic monoarthritis in a pediatric patient due to shewanella putrefaciens: case report and literature review.

BACKGROUND: Shewanella putrefaciens is a gram-negative, nonfermenting, oxidase-positive, hydrogen sulfide-producing bacillus and a halophilic bacterium, known for causing unusual infections in humans and often regarded as an opportunistic pathogen. Its diverse symptoms have a significant impact on human health, with 260 documented disorders reported in the literature over the last 40 years, highlighting its potential danger. CASE PRESENTATION: We present the case of a previously healthy 15-year-old male patient who sustained a self-inflicted sharp-object injury while working in the field, resulting in secondary septic monoarthritis due to Shewanella putrefaciens. CONCLUSIONS: This case highlights the bacteriological and clinical characteristics, as well as the antibiogram, of Shewanella spp. Given the recent increase in notifications of Shewanella infections, predominantly by S. algae and S. putrefaciens, it is essential to consider these pathogens in patients with a history of contact with bodies of water. Special attention must be paid to their resistance patterns in patient management to prevent the development of intrinsic antimicrobial resistance.

Anterior cruciate ligament femoral side retained stump technique reduces enlargement of the femoral bone tunnel after anterior cruciate ligament reconstruction.

BACKGROUND: Enlargement of the bone tunnel has become an unavoidable early complication after anterior cruciate ligament (ACL) reconstruction, whether it is a single or double-bundle ACL reconstruction. Preservation of the ACL stump in ACL reconstruction reduces enlargement of the bone tunnel. The purpose of this study was to investigate the question of whether single-bundle ACL reconstruction using the ACL femoral side retained stump technique reduces enlargement of the femoral tunnel. METHODS: Forty patients who underwent single-bundle reconstruction of the ACL were included in this study. The patients were categorized into a Remnant preservation group (Group R) and the Non-remnant preservation group (Group N). In the Remnant preservation group, a high-flexion femoral side retained stump technique was used intraoperatively for the establishment of the femoral side bone tunnel, and in the Non-remnant preservation group, the conventional femoral positioning method was used (we used a femoral positioning drill for localization and drilling of the femoral bone tunnel), and MRI of the operated knee joints was performed at 6 months postoperatively. We measured the internal diameter of the femoral bone tunnel at 5 mm from the intra-articular outlet of the femoral bone tunnel on an MRI scan image perpendicular to the femoral bone tunnel. The size of the tunnel was compared between the intraoperative drilling of the bone tunnel and the size of the bone tunnel at 6 months postoperatively. Postoperative clinical assessment was Lysholm score. RESULTS: After a 6-month follow-up of 40 patients, the diameter of the femoral tunnel at a distance of 5 mm from the inner opening of the femoral tunnel was 10.96 ± 0.67 mm and 10.11 ± 0.62 mm in patients of group N and group R, respectively, and the difference was statistically significant (P < 0.05).The diameter of the femoral tunnel at 6 months postoperatively in group N and group R compared to the intraoperative bone tunnel increased by 2.58 ± 0.24 mm and 1.94 ± 0.31 mm, and the difference was statistically significant (P < 0.05).The femoral tunnel enlargement rates of group N and group R were 30.94 ± 3.00% and 24.02 ± 5.10%, respectively, and the differences were significant (P < 0.05). CONCLUSION: ACL femoral side retained stump technique does not sacrifice the ideal location of the femoral tunnel and is able to preserve the possible benefits of the ACL stump: reduced femoral tunnel enlargement.

Robot-assisted total knee arthroplasty system provides more precise control of the femoral rotation angle: A retrospective study.

BACKGROUND: Rotational alignment in total knee arthroplasty (TKA) is a crucial technical point that needs attention. We conducted a retrospective study to investigate whether a new robot-assisted TKA (RA-TKA) could improve the accuracy of rotational alignment and whether rotational alignment affects postoperative pain and functional evaluation of the knee. METHODS: A total of 136 consecutive patients who underwent TKA were included in this study. Half of the patients underwent RA-TKA and the other half underwent conventional TKA (CON-TKA) by the same group of surgeons. Collect the relevant parameters. RESULTS: The postoperative femoral rotation angle (FRA) was -0.72 ± 2.59° in the robot-assisted group and 1.13 ± 2.73° in the conventional group, and were statistically significantly different (p < 0.001). CONCLUSION: This study provides preliminary evidence that the RA-TKA provides more precise control of FRA than CON-TKA, and verifies that tibial rotation angle and combined rotation angle affect postoperative knee pain and functional evaluation.

Efficiency assessment of follow-up methodology of patients with knee replacement to predict post-surgical functionality: a protocol for randomised control PROKnee trial.

INTRODUCTION: Even when total knee arthroplasty (TKA) is an extended treatment, most patients experience a suboptimal evolution after TKA. The objectives of this study are the following: (1) to determine the effectiveness of two different prosthesis stabilisation systems on the functionality in activities of daily life, and (2) to determine prognostic biomarkers of knee prosthesis function based on radiological information, quantification of cytokines, intra-articular markers and biomechanical functional evaluation to predict successful evolution. METHODS AND ANALYSIS: The PROKnee trial was designed as a randomised controlled patient-blinded trial with two parallel groups that are currently ongoing. The initial recruitment will be 99 patients scheduled for their first TKA, without previous prosthesis interventions in lower limbs, who will be randomly divided into two groups that differed in the stabilisation methodology incorporated in the knee prosthesis: the MEDIAL-pivot group and the CENTRAL-pivot group. The maximum walking speed will be reported as the primary outcome, and the secondary results will be patient-reported questionnaires related to physical status, cognitive and mental state, radiological test, laboratory analysis and biomechanical instrumented functional performance, such as the 6-minute walking test, timed up-and-go test, gait, sit-to-stand, step-over, and ability to step up and down stairs. All the results will be measured 1 week before TKA and at 1.5, 3, 6 and 12 months after surgery. ETHICS AND DISSEMINATION: All procedures were approved by the Ethical Committee for Research with Medicines of the University Clinical Hospital of Valencia on 8 October 2020 (order no. 2020/181). Participants are required to provide informed consent for the study and for the surgical procedure. All the data collected will be treated confidentially since they will be blinded and encrypted. The results from the trial will be published in international peer-reviewed scientific journals, regardless of whether these results are negative or inconclusive. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT04850300).

Design and validation of a wearable dynamometry system for knee extension-flexion torque measurement.

Muscle strength assessments are vital in rehabilitation, orthopedics, and sports medicine. However, current methods used in clinical settings, such as manual muscle testing and hand-held dynamometers, often lack reliability, and isokinetic dynamometers (IKD), while reliable, are not easily portable. The aim of this study was to design and validate a wearable dynamometry system with high accessibility, accuracy, and reliability, and to validate the device. Therefore, we designed a wearable dynamometry system (WDS) equipped with knee joint torque sensors. To validate this WDS, we measured knee extension and flexion strength in 39 healthy adults using both the IKD and WDS. Comparing maximal isometric torque measurements, WDS and IKD showed strong correlation and good reliability for extension (Pearson's r: 0.900; intraclass correlation coefficient [ICC]: 0.893; standard error of measurement [SEM]: 9.85%; minimal detectable change [MDC]: 27.31%) and flexion (Pearson's r: 0.870; ICC: 0.857; SEM: 11.93%; MDC: 33.07%). WDS demonstrated excellent inter-rater (Pearson's r: 0.990; ICC: 0.993; SEM: 4.05%) and test-retest (Pearson's r: 0.970; ICC: 0.984; SEM: 6.15%) reliability during extension/flexion. User feedback from 35 participants, including healthcare professionals, underscores WDS's positive user experience and clinical potential. The proposed WDS is a suitable alternative to IKD, providing high accuracy, reliability, and potentially greater accessibility.

Factors influencing the posterior cruciate ligament buckling phenomenon-a multiple linear regression analysis of bony and soft tissue structures of the knee joint.

PURPOSE: To determine whether posterior cruciate ligament (PCL) buckling (angular change) is associated with anterior cruciate ligament (ACL) status (intact or ruptured), meniscal bone angle (MBA), anterior tibial translation (ATT), body weight, femoral-tibial rotation (FTR), posterior tibial slope (PTS), PCL length and femoral-tibial distance (FTD) and to identify the factors that have the greatest influence. METHODS: All enrolled participants were scanned with a 3.0 T, 8-channel coil MRI system (Magnetom Verio; Siemens). Bone and soft tissue parameters were measured by MIMICS software for each subject and each measured parameter was correlated with PCL buckling phenomena. The correlated and statistically significant parameters were then analyzed by multiple linear regression to determine the magnitude of the effect of the different parameters on the PCL buckling phenomenon. RESULTS: A total of 116 subjects (50 ACL ruptured and 66 age, weight and height matched volunteers with uninjured knees) were enrolled. Among all measured parameters, there were 8 parameters that correlated with PCL angle (PCLA), of which ACL status had the strongest correlation with PCLA (r = - 0.67, p = < 0.001); and 7 parameters that correlated with PCL-posterior femoral cortex angle (PCL-PCA), of which ATT had the strongest correlation with PCL-PCA (r = 0.69, p = < 0.001). PCLIA was not significantly correlated with any of the measured parameters. Multiple linear regression analyses revealed four parameters can explain PCLA, of which ACL status had the strongest effect on PCLA (absolute value of standardized coefficient Beta was 0.508). Three parameters can explain PCL-PCA, of which ATT had the strongest effect on PCLIA (r = 0.69, p = < 0.001), ATT has the greatest effect on PCL-PCA (absolute value of normalized coefficient Beta is 0.523). CONCLUSIONS: PCLA may be a simple and easily reproducible and important supplement for the diagnosis of ACL injury; PCL-PCA is a simple and easily reproducible and important complementary tool for the detection of ATT. The use of PCLA is more recommended to aid in the diagnosis of ACL injury.

Posture-induced modulation of lower-limb joint powers in perturbed running.

Despite evidence on trunk flexion's impact on locomotion mechanics, its role in modulating lower-limb energetics during perturbed running remains underexplored. Therefore, we investigated posture-induced power redistribution in the lower-limb joints (hip, knee, and ankle), along with the relative contribution from each joint to total lower-limb average positive and negative mechanical powers (i.e., over time) during perturbed running. Twelve runners (50% female) ran at self-selected (~15°) and three more sagittal trunk inclinations (backward, ~0°; low forward, ~20°; high forward, ~25°) on a custom-built runway, incorporating both a level surface and a 10 cm visible drop-step positioned midway, while simultaneously recording three-dimensional kinematics and kinetics. We used inverse dynamics analysis to determine moments and powers in lower-limb joints. Increasing the trunk forward inclination yielded the following changes in lower-limb mechanics: a) an elevation in total positive power with a distoproximal shift and a reduction in total negative power; b) systematic increases in hip positive power, coupled with decreased and increased contribution to total negative (during level-step) and positive (during drop-step) powers, respectively; c) reductions in both negative and positive knee powers, along with a decrease in its contribution to total positive power. Regardless of the trunk posture, accommodating drop-steps while running demands elevated total limb negative and positive powers with the ankle as a primary source of energy absorption and generation. Leaning the trunk more forward induces a distoproximal shift in positive power, whereas leaning backward exerts an opposing influence on negative power within the lower-limb joints.

Prediction of specific structural damage to the knee joint using qualitative isokinetic analysis.

BACKGROUND: An isokinetic moment curve (IMC) pattern-damaged structure prediction model may be of considerable value in assisting the diagnosis of knee injuries in clinical scenarios. This study aimed to explore the association between irregular IMC patterns and specific structural damages in the knee, including anterior cruciate ligament (ACL) rupture, meniscus (MS) injury, and patellofemoral joint (PFJ) lesions, and to develop an IMC pattern-damaged structure prediction model. METHODS: A total of 94 subjects were enrolled in this study and underwent isokinetic testing of the knee joint (5 consecutive flexion-extension movements within the range of motion of 90°-10°, 60°/s). Qualitative analysis of the IMCs for all subjects was completed by two blinded examiners. A multinomial logistic regression analysis was used to investigate whether a specific abnormal curve pattern was associated with specific knee structural injuries and to test the predictive effectiveness of IMC patterns for specific structural damage in the knee. RESULTS: The results of the multinomial logistic regression revealed a significant association between the irregular IMC patterns of the knee extensors and specific structural damages ("Valley" - ACL, PFJ, and ACL + MS, "Drop" - ACL, and ACL + MS, "Shaking" - ACL, MS, PFJ, and ACL + MS). The accuracy and Macro-averaged F1 score of the predicting model were 56.1% and 0.426, respectively. CONCLUSION: The associations between irregular IMC patterns and specific knee structural injuries were identified. However, the accuracy and Macro-averaged F1 score of the established predictive model indicated its relatively low predictive efficacy. For the development of a more accurate predictive model, it may be essential to incorporate angle-specific and/or speed-specific analyses of qualitative and quantitative data in isokinetic testing. Furthermore, the utilization of artificial intelligence image recognition technology may prove beneficial for analyzing large datasets in the future.

The Vega advanced third generation posterior stabilized total knee arthroplasty system enables the restoration of range of motion for high demanding daily activities - A 5-years follow-up study.

BACKGROUND: The Vega System® PS (Aesculap AG, Tuttlingen, Germany) is an advanced, third generation fixed implant that aims to mimic natural knee kinematics by optimizing pivotal motion while reducing surface stress. This study evaluated mid-term survival and clinical outcomes, including range of motion (ROM) of the modern posterior stabilized implant in order to analyse whether this biomechanically successful implant reaches good results in situ. METHODS: The first 100 patients to receive the Vega PS System for total knee arthroplasty were invited to take part in this single centre, single surgeon study. Of these, 84 patients were clinically assessed 5-6 years postoperatively. Data which was obtained during this follow-up examination included revision data, range of motion and clinical scores. RESULTS: The 5-year survival rate for exchange of any component was 97.6%, whereby two patients required replacement of the polyethylene gliding surface. Secondary patella resurfacing was performed in 7 patients. Significantly improved results in comparison to the preoperative state could be obtained at the follow-up: KOOS improved from 39.4 to 78.8, SF-12 PCS improved from 32.1 to 42 SF-12 MCS improved from 46 to 53.8 and patella pain improved from 2.7 to 0.3. The mean ROM of the 84 patients after 5 years was 133.1° and mean total KSS was 189.9. DISCUSSION & CONCLUSIONS: This study demonstrates a high survival rate of the Vega PS System® and significant improvements in clinical outcomes 5 years after implantation. The obtained mean ROM indicates that this implant provides good flexibility of the knee joint, allowing a high number of activities. However, due to the rate of secondary patella implantation, routine resurfacing of the patella for all PS TKA cases is highly recommended. CLINICAL TRIALS REGISTRATION: The study was registered at clinicaltrials.gov (NCT02802085).

Combining enhanced spectral resolution of EMG and a deep learning approach for knee pathology diagnosis.

Knee osteoarthritis (OA) is a prevalent, debilitating joint condition primarily affecting the elderly. This investigation aims to develop an electromyography (EMG)-based method for diagnosing knee pathologies. EMG signals of the muscles surrounding the knee joint were examined and recorded. The principal components of the proposed method were preprocessing, high-order spectral analysis (HOSA), and diagnosis/recognition through deep learning. EMG signals from individuals with normal and OA knees while walking were extracted from a publicly available database. This examination focused on the quadriceps femoris, the medial gastrocnemius, the rectus femoris, the semitendinosus, and the vastus medialis. Filtration and rectification were utilized beforehand to eradicate noise and smooth EMG signals. Signals' higher-order spectra were analyzed with HOSA to obtain information about nonlinear interactions and phase coupling. Initially, the bicoherence representation of EMG signals was devised. The resulting images were fed into a deep-learning system for identification and analysis. A deep learning algorithm using adapted ResNet101 CNN model examined the images to determine whether the EMG signals were conventional or indicative of knee osteoarthritis. The validated test results demonstrated high accuracy and robust metrics, indicating that the proposed method is effective. The medial gastrocnemius (MG) muscle was able to distinguish Knee osteoarthritis (KOA) patients from normal with 96.3±1.7% accuracy and 0.994±0.008 AUC. MG has the highest prediction accuracy of KOA and can be used as the muscle of interest in future analysis. Despite the proposed method's superiority, some limitations still require special consideration and will be addressed in future research.

Association of Preoperative Subchondral Bone Marrow Oedema with Outcomes after Lateral Unicompartmental Knee Arthroplasty.

OBJECTIVE: To determine whether the presence of preoperative subchondral bone marrow oedema (SBME) is associated with inferior outcomes after lateral unicompartmental knee arthroplasty (LUKA). STUDY DESIGN: Descriptive study. Place and Duration of the Study: Department of Orthopaedic Surgery, Chongqing Orthopaedic Hospital of Traditional Chinese Medicine, Chongqing, China, from January 2019 to June 2022. METHODOLOGY: Data on patients treated with LUKA were obtained from the Medical Registry Database. Two groups were made based on the presence and absence of SBME on preoperative magnetic resonance imaging (MRI). The visual analogue scale (VAS), American Knee Society Scores (AKSS), and rate of patient satisfaction were compared between the two groups. RESULTS: A total of 20 patients treated with LUKA were reviewed. The SBME was present in 9 cases and absent in 11 cases. Patients with SBME had inferior scores at preoperative evaluation and at 1, 3, and 6 months postoperatively. However, there was no significant difference between the groups at the 12-month follow-up. Eight (88.9%) patients with SBME were satisfied with the LUKA surgery versus 9 (81.8%) patients without SBME, showing no significant differences between groups. CONCLUSION: Presence of preoperative SBME is associated with inferior functional outcomes after LUKA within six months of follow-up. KEY WORDS: Bone marrow, Oedema, Knee, Arthroplasty, Outcome, Patient satisfaction.

A new and simple method for patellar height measurement: Fibula-condyle-patella angle.

OBJECTIVES: This study aims to evaluate the inter-observer reliability of fibula-condyle-patella angle measurements and to compare it with other measurement techniques. PATIENTS AND METHODS: Between January 01, 2023 and January 31, 2023, a total of 108 patients (20 males, 88 females; mean age: 47.5±12.0 years; range, 18 to 72 years) who underwent X-rays using the fibula-condyle-patella angle, Insall-Salvati, Caton-Deschamps, Blackburne-Pell, and plateau-patella angle (PPA) methods were retrospectively analyzed. Knee lateral radiographs taken in at least 30 degrees of flexion and appropriate rotation were scanned. All measurements were made by two orthopedic surgeons who were blinded to measurement methods. RESULTS: Right knee patellar height measurements were conducted in 56 patients, while left knee patellar heights were assessed in 52 patients. The highest inter-observer concordance was found in the fibula-condyle-patella angle. The second highest concordance was found in the Insall-Salvati. The highest concordance correlation was found with PPA in the measurements of both researchers. CONCLUSION: The fibula-condyle-patella angle is a reliable technique with a good inter-observer reliability for measuring patellar height. We believe that this study will inspire future research to establish comprehensive reference values for clinical applications.

Evaluation of the relationship between the anatomical characteristics of the vastus medialis obliquus muscle and the patella chondral lesion occurrence.

OBJECTIVES: The study aims to investigate the relationship between the vastus medialis obliquus (VMO) muscle distal insertion features and patellar chondral lesion presence. PATIENTS AND METHODS: This cross-sectional study included a total of 100 patients (18 males, 82 females, mean age 67.2±7.1 years; range, 50 to 86 years) who underwent total knee arthroplasty (TKA). Radiological assessments, including merchant view and standing orthoroentgenograms, were conducted. The current osteoarthritis stage, varus angle, quadriceps angle (Q angle), patella-patellar tendon angle (P-PT angle), congruence angle, and sulcus angle were calculated. The VMO tendon length, muscle fiber angle, tendon insertion width measurements, and patellar chondral lesion localization data were obtained intraoperatively. Grouping was done according to the distal insertion width of the VMO tendon to the medial edge of the patella. The medial rim of the patella was divided into three equal-sized sectors. The first group (Group 1, n=31) consisted of patients who had an insertion from the quadriceps tendon into the upper one-third of the patella. The second group (Group 1, n=48) consisted of patients with a distal insertion expanding into the middle one-third of the patella. The third group (Group 3, n=21) consisted of patients who had a distal insertion extending into the distal third region of the medial patella margin. The patella joint surface was divided into sectors, and the presence and location of cartilage lesions were noted in detail. RESULTS: The mean tendon insertion width rate was 45.99±16.886% (range, 16.7 to 83.3%). The mean muscle fiber insertion angle was 51.85±11.67º (range, 20º to 80º). The mean tendon length was 12.45±3.289 (range, 4 to 20) mm. There was no significant difference between the mean age, weight, height, body mass index, BMI, fiber angle, tendon length, varus angle, Q angle, sulcus angle, and congruence angle data among the groups. In terms of the P-PT angle, Groups 1 and 2 had a significant relationship (p=0.008). No relationship was found between the mean fiber insertion angle, mean tendon length, or the presence of chondral lesions. There was a statistically significant difference among the groups regarding the presence of chondral lesions. The highest percentage of chondral lesion frequency was observed in Group 3 (95.24%), followed by Group 1 (90.3%) and Group 2 (89.6%), respectively. Compared to the other two groups, Group 3 had a higher average ratio of lesion areas per patient. CONCLUSION: Our study results demonstrate that the formation and localization of the patellar chondral lesions are affected by the insertion width type of the VMO muscle into the patella. Group 2-type insertion is associated with a lower lesion frequency rate than Groups 1 and 3.

Gerdy's tubercle as a novel anatomical landmark for the proximal tibial cut in total knee arthroplasty.

OBJECTIVES: This study aimed to explore the use of Gerdy's tubercle (GT) as an innovative and dependable anatomical landmark for the proximal tibial cut in total knee arthroplasty (TKA) in cases with extensive knee degeneration. MATERIALS AND METHODS: One hundred dry tibia bones and 10 formalin-fixed cadaveric knee specimens of both sexes were examined. A Zimmer NexGen tibial cutting guide and a Mitutoyo digital caliper were utilized to align the guide with the tibia's mechanical axis. The procedure was replicated on cadaver knees using a standardized medial parapatellar arthrotomy approach. Measurements included the distance from GT superior border to the resection line and the length of the tibia. A radiological study involving magnetic resonance imaging examinations of 48 patients, which were evaluated focusing on the upper border of GT and the least degenerated segment of the posterolateral part of the lateral tibial condyle, was conducted. RESULTS: Anatomical measurements of GT and proximal tibial areas in 110 specimens showed slight but consistent variations with cadaver measurements. Magnetic resonance imaging analysis of 48 patients revealed notable sex differences in the distance between the superior border of GT and the tibia's posterolateral surface. There was also a significant negative correlation between the distance from GT to the posterolateral corner and cartilage thickness. CONCLUSION: Proper alignment in TKA is crucial for success, but identifying an extra-articular landmark for horizontal tibial resection remains challenging, particularly in severely arthritic knees. This study introduces GT as a novel anatomical landmark for TKA, offering a more reliable reference for achieving desired joint levels in knees with significant degenerative changes.

A comparative analysis of 3D bioprinted gelatin-hyaluronic acid-alginate scaffold and microfracture for the management of osteochondral defects in the rabbit knee joint.

OBJECTIVES: This study aims to compare the radiological, biomechanical, and histopathological results of microfracture treatment and osteochondral damage repair treatment with a new scaffold product produced by the three-dimensional (3D) bioprinting method containing gelatin-hyaluronic acid-alginate in rabbits with osteochondral damage. MATERIALS AND METHODS: A new 3D bioprinted scaffold consisting of gelatin, hyaluronic acid, and alginate designed by us was implanted into the osteochondral defect created in the femoral trochlea of 10 rabbits. By randomization, it was determined which side of 10 rabbits would be repaired with a 3D bioprinted scaffold, and microfracture treatment was applied to the other knees of the rabbits. After six months of follow-up, the rabbits were sacrificed. The results of both treatment groups were compared radiologically, biomechanically, and histopathologically. RESULTS: None of the rabbits experienced any complications. The magnetic resonance imaging evaluation showed that all osteochondral defect areas were integrated with healthy cartilage in both groups. There was no significant difference between the groups in the biomechanical load test (p=0.579). No statistically significant difference was detected in the histological examination using the modified Wakitani scores (p=0.731). CONCLUSION: Our study results showed that 3D bioprinted scaffolds exhibited comparable radiological, biomechanical, and histological properties to the conventional microfracture technique for osteochondral defect treatment.

Simultaneous medial closing wedge distal femoral varus osteotomy and double-bundle anterior cruciate ligament reconstruction in the symptomatic femoral valgus deformity: A case report.

Distal femoral varus osteotomy (DFVO) is a widely recognized surgical procedure used to address valgus malalignment in patients with knee joint disorders. However, it still remains unclear whether anterior cruciate ligament (ACL) reconstruction can be performed in a single procedure along with DFVO. Herein, we present a 73-year-old female patient who developed lateral osteoarthritis of the knee with valgus alignment due to chronic ACL deficiency following a twisting injury during skiing. She was physiologically very active, and strongly demanded to return to sports. We performed a combined procedure involving a medial closing wedge DFVO using an anatomical locking plate, along with double-bundle ACL reconstruction. The postoperative radiograph confirmed successful correction of knee alignment, specifically achieving varus alignment with precise conformance of the anatomical plate to the medial contour of the distal femur following the osteotomy. The patient resumed her previous sports activities without experiencing knee pain. The operated knee demonstrated restored anterior stability, as indicated by negative Lachman test results, and regained full range of motion. Both the Knee Injury and Osteoarthritis Outcome Score and the 2011 Knee Society score demonstrated continuous postoperative improvements over the three-year follow-up period, indicating positive functional outcomes and joint preservation. To the best of our knowledge, this is the first case of medial closing wedge DFVO with anatomic double-bundle ACL reconstruction in the symptomatic femoral valgus deformity with chronic ACL deficiency in the literature.

Impact of postoperative femorotibial axis on functional outcomes in unicompartmental knee arthroplasty.

OBJECTIVES: This study aimed to compare the functional outcomes of patients undergoing fixed-bearing medial unicompartmental knee arthroplasty (UKA) classified as either varus or neutral based on their postoperative femorotibial angle (FTA), with the goal of evaluating the impact of FTA on functional results. PATIENTS AND METHODS: A total of 38 knees of 35 patients (27 females, 8 males; mean age: 63.6±7.1 years; range, 52 to 75 years) were included in this retrospective study. The data was collected between December 15, 2020, and January 15, 2021. Patients were categorized into two groups based on their postoperative FTA. The neutral group consisted of patients with an FTA range of 5.1° to 7.4°, while the varus group included patients with an FTA range of 0.1° to 4.8°. Knee Outcome Osteoarthritis Score (KOOS), Visual Analog Scale (VAS) scores, sit to stand test results, and six minute walk test data were analyzed. RESULTS: The mean follow-up was 42.0±19.3 months. The postoperative VAS score for the varus group was 0.95±0.99, whereas the neutral group had a VAS score of 2.19±1.83 (p=0.021). The mean KOOS for the varus group was 88.01±7.88, whereas the neutral group had a mean KOOS score of 78.46±13.69 (p=0.006). CONCLUSION: In patients undergoing UKA, mild varus alignment could yield superior early and midterm functional outcomes compared to a neutral femorotibial angle.