Increase in Postoperative Body Mass Index in Patients After Total Knee Arthroplasty.

Objectives The aim of this is to investigate the changes in body mass index (BMI) following knee arthroplasty and to evaluate their impact on patient-reported outcomes and functional evaluations. Methods This observational study included 90 patients who underwent total knee arthroplasty (TKA) and were followed up for a median period of 2.6 years. BMI measurements were recorded before and after surgery, and patient-reported outcomes and functional evaluations were assessed using standardized scales and tests. Results Following TKA, BMI increased statistically significantly (Wilcoxon signed-rank test, p < 0.000). In addition, half of the patients experienced an increase in BMI, with 32% moving up in their BMI category. However, there were no clinically significant differences in patient-reported outcomes or functional evaluations between the group that gained BMI and the group that maintained or lost BMI. Conclusion This study reveals that patients tend to have increased BMI following TKA. However, these BMI changes do not significantly impact patient-reported outcomes or functional evaluations. It underscores the importance of patient education regarding healthy lifestyle habits, including diet and physical activity, to address postoperative weight gain effectively.

Anterior knee pain and sit-up tests predicts patients' satisfaction and improvement in quality of life after anterior stabilized total knee replacement without patellar resurfacing.

PURPOSE: The purpose of this study was to assess patient satisfaction and identify risk factors for dissatisfaction after anterior stabilised conventional total knee arthroplasty (TKA) without patellar resurfacing, using the Goodman score. METHODS: We conducted a cross-sectional study using data from our institutional database from 1 January 2018 to 1 March 2021. Patients who underwent TKA with the Vanguard® Cruciate Retaining Anterior Stabilized Knee System (Zimmer Biomet, Warsaw, Indiana, USA) without patellar replacement were included. Patients with other bearing surfaces (posterior stabilised or medial congruent) or diagnosed with infection or instability were excluded. Patients' reported outcomes, body mass index (BMI), passive range of motion, the timed up-and-go test, sit-up test, and algometry were assessed. Patients were also asked if they had anterior knee pain. Satisfaction was assessed using the Goodman scale, and logistic multivariate regression was used to identify variables associated with dissatisfaction and perceived improvement in quality of life. RESULTS: A total of 131 TKA patients were included in the study. The median satisfaction score was 100 (interquartile range [IQR], 87.5 to 100), with the 75-point threshold at the 90th percentile according to Section A of Goodman. Section B of Goodman showed that 113 TKA patients (86.26%) reported "great improvement" or "more than I ever dreamed." Multivariate logistic regression revealed that anterior knee pain (OR 5.16, 95% CI 1.24 to 21.39), the sit-up test (OR 0.63, 95% CI 0.49 to 0.81), and BMI (OR 0.84, 95% CI 0.70 to 0.99) were significantly associated with patient dissatisfaction and a worse perceived improvement in quality of life. The receiver operating characteristics curve for the models had areas under the curve of 0.83 (95% CI 0.69 to 0.97) and 0.82 (95% CI 0.70 to 0.94), respectively. CONCLUSION: Anterior stabilised TKA without patellar resurfacing can achieve 90% satisfaction and 86% improvement in quality of life. To improve these results, it is essential to prevent and treat anterior knee pain and enhance quadriceps strength. LEVEL OF EVIDENCE: Level III (retrospective cohort study).

Gonyautoxins 2/3 Local Periarticular Injection for Pain Management after Total Knee Arthroplasty: A Double-Blind, Randomized Study.

The purpose of this study was to compare the efficacy of periarticular infiltration of gonyautoxin 2/3 (GTX 2/3) and a mixture of levobupivacaine, ketorolac, and epinephrine for pain management after total knee arthroplasty (TKA). Forty-eight patients were randomly allocated to receive periarticular infiltration of 40 µg GTX 2/3 (n = 24) diluted in 30 mL of sodium chloride 0.9% (study group) or a combination of 300 mg of levobupivacaine, 1 mg of epinephrine, and 60 mg ketorolac (n = 24) diluted in 150 mL of sodium chloride 0.9% (control group). Intraoperative anesthetic and surgical techniques were identical for both groups. Postoperatively, all patients received patient-controlled analgesia (morphine bolus of 1 mg; lockout interval of 8 minutes), acetaminophen, and ketoprofen for 72 hours. A blinded investigator recorded morphine consumption, which was the primary outcome. Also, the range of motion (ROM) and static and dynamic pain were assessed at 6, 12, 36, and 60 hours after surgery. The incidence of adverse events, time to readiness for discharge, and length of hospital stay were also recorded. The median of total cumulative morphine consumption was 16 mg (range, 0-62 mg) in the GTX 2/3 group and 9 mg (range, 0-54 mg) in control group, which did not reach statistical difference (median test, p = 0.40). Furthermore, static and dynamic pain scores were similar at all time intervals. GTX 2/3 was inferior in range of motion at 6 and 12 hours; nevertheless, we noted no difference after 36 hours. No differences between groups were found in terms of complications, side effects, or length of hospital stay. No significant differences were found between groups in terms of breakthrough morphine requirement. However, local anesthetic use resulted in an increased ROM in the first 12 hours. This prospective randomized clinical trial shows that GTX 2/3 is a safe and efficient drug for pain control after TKA; nevertheless, more studies using GTX 2/3 with larger populations are needed to confirm the safety profile and efficiency. This is level 1 therapeutic study, randomized, double-blind clinical trial.

Cohorte histórica de artroplastia unicompartimental de rodilla en un hospital universitario chileno / Historical cohort of unicompartmental knee arthroplasty in a Chilean university hospital

OBJETIVO Describir el resultado funcional informado por el paciente de una cohorte de pacientes sometidos a artroplastia unicompartimental de rodilla (AUR) en un hospital universitario chileno. MÉTODOS Se diseñó un estudio de cohorte histórica. Se incluyeron todos los pacientes que se sometieron a AUR de platillo fijo entre 2003 y 2019. Un evaluador independiente se puso en contacto con los pacientes en junio de 2020. Se utilizó el índice de artritis de las universidades de Western Ontario y McMaster (WOMAC) para comparar los procedimientos de AUR (medial o lateral), la edad (mayor o menor de 70 años), y el seguimiento (más o menos de 5 años). RESULTADOS Se incluyeron 78 pacientes, en un total de 94 AURs. La mediana de edad fue de 64 años (rango: 43 a 85 años). Hubo 72 (76,6%) casos de AUR medial. Un paciente necesitó revisión para artroplastia total de rodilla (ATR). Un total de 60 pacientes (76,9%), correspondientes a 72 AURs (76,7%), fueron contactados con éxito por teléfono para el seguimiento final. La mediana del puntaje en los dominios del WOMAC fue: dolor ­ 1 (rango: 0 a 12); rigidez ­ 0 (rango: 0 a 4); y función física ­ 2 (rango: 0 a 29). La mediana del puntaje total en el WOMAC fue de 4 (rango: 0 a 44). Los pacientes sometidos a AUR lateral lograron mejores puntuaciones funcionales (p » 0,0432), y el puntaje total en el WOMAC fue similar en pacientes mayores o menores de 70 años (p » 0,3706). CONCLUSIONES La AUR es un tratamiento eficaz y reproducible para pacientes con artrosis de rodilla unicompartimental. La edad parece no afectar los resultados funcionales, y la AUR es un tratamiento eficaz en pacientes mayores de 70 años. Estos resultados deberían animar a los cirujanos de rodilla a aprender esta técnica y a los responsables de las políticas de salud pública a considerar la AUR para la osteoartritis de rodilla.

PURPOSE To describe the patient-reported functional outcome of a cohort of patients undergoing unicompartmental knee arthroplasty (UKA) in a Chilean university hospital. METHODS A historical cohort study was designed. All patients who underwent fixedbearing UKA between 2003 and 2019 were included. An independent evaluator contacted the patients in June 2020. The Western Ontario and McMaster Universities Arthritis Index (WOMAC) was used to compare UKA procedures (medial or lateral), age (over or under 70 years), and follow up (longer or shorter than 5 years). RESULTS A total of 78 patients, corresponding to 94 UKAs, were included. The median age was 64 years (range: 43 to 85 years). There were 72 (76.6%) cases of medial UKA. One patient needed revision to total knee arthoplasty (TKA). A total of 60 patients (76.9%), corresponding to 72 UKAs, were successfully contacted by phone for the final follow-up. The median scores on the WOMAC domains were: pain ­ 1 (range: 0 to 12); stiffness ­0 (range: 0 to 4); and physical function ­ 2 (range: 0 to 29). The median total score on the WOMAC was 4 (range: 0 to 44). Patients submitted to lateral UKA had better functional scores (p » 0.0432), and the total WOMAC score was similar among patients older or younger than 70 years of age (p » 0.3706). CONCLUSIONS For patients with unicompartmental knee osteoarthritis, UKA is an effective and reproducible treatment. Age does not seem to affect the functional results, and UKA is an effective treatment in patients over 70 years old. These results should encourage knee surgeons to learn this technique and those responsible for public health policies to consider UKA for knee osteoarthritis

Impact of the COVID-19 Outbreak on Orthopedic Surgery: A Nationwide Analysis of the First Pandemic Year.

Purpose To analyze the impact of the coronavirus disease 2019 (COVID-19) outbreak during the first pandemic year in a single country. Methods A cross-sectional study was designed. The free access database of the Chilean Department of Statistics and Health Information (DEIS) was used to compare the number of orthopedic procedures between 2019 and 2020. Country mobility was exported from the Institute of Complex Engineering Systems (ISCI) free-access database; this corresponds to a direct measurement of the degree of confinement of the country. Spearman correlation (rho) was used to analyze the total monthly COVID infection trend and mobility to orthopedics procedures. Results The number of orthopedic surgeries fell by 22.8% during the first year of the pandemic. All surgical procedures were adversely affected, with the fracture/trauma surgeries being the least affected. The maximum adverse impact was seen in knee arthroplasty (-64%), followed by hip arthroplasty (-41%) and knee ligament reconstruction (-44%). The number of orthopedic procedures had a mild correlation to the monthly number of COVID-19 cases (rho=-0.53, p=0.08) and a strong correlation with the country's mobility (rho=0.94, p=0.0001). Conclusions The COVID-19 outbreak diminished the number of orthopedic procedures during 2020, and the impact was directly correlated to the country's mobility. The public health network did have a more significant adverse impact in elective surgeries due to a slower recovery than private institutions. An increase in the waiting list should be expected, which will widen the difference in access to orthopedic surgery in Chile.

Construct Validity of a Virtual Reality Simulator for Surgical Training in Knee Arthroscopy.

Objective Surgical techniques are learned gradually throughout an orthopedic residency. Training on real patients carries drawbacks such as limited access and elevated risk. Alternatively, surgical simulation allows residents to practice in a safe environment with greater access to standardized surgical tasks. Virtual reality simulators display images inside an artificial joint, often providing real-time haptic feedback to allow for realistic interaction. The objective of this study was to evaluate the construct validity of a virtual reality simulator for knee arthroscopy by analyzing the capacity of system parameters to distinguish between expert and novice surgeons. Design This comparative cross-sectional study contrasts the automated performance reports for novice and expert orthopedic surgeons after executing surgical tasks on the ARTHRO Mentor virtual reality simulator. Setting Surgical simulation center at the University of Chile Clinical Hospital, Santiago, Chile. Participants The novice group consisted of 20 second-year orthopedic and traumatology residents at the University of Chile School of Medicine. The expert group consisted of 10 experienced arthroscopic surgeons. All participants carried out standardized tasks in the knee arthroscopy virtual reality simulator. The median performance scores of the two groups were compared, and multivariate logistic regression was performed to assess the capacity of the system to discriminate between the two groups. Results Median performance on the vast majority of surgical tasks was superior for the expert group. The expert group had performance values equal to or higher than the novice group on 43 of the 44 variables recorded for the basic tasks and 74 of the 75 advanced task variables. The multivariate logistic regression analysis discriminated expert from novice users with 100% accuracy. Conclusion The virtual reality simulator for knee arthroscopy showed good construct validity, with performance metrics accurately discriminating between expert and novice users.

The Distance between Tibial Tubercle and Trochlear Groove Correlates with Knee Articular Torsion.

This study aims to correlate the tibial tubercle to trochlear groove (TT-TG) distance with knee axial alignment. The hypothesis is that as internal torsion of the distal femur or external torsion of the proximal tibial increases, the TT-TG distance increases. We designed a cross-sectional study approved by our institutional ethics review board. We reviewed 32 computed tomography angiographies of patients that have nonjoint or bone-related symptoms. Distal femoral torsion, proximal tibial torsion, knee articular torsion (AT), and TT-TG distance were measured. A regression analysis between the TT-TG distance and the AT was performed. A positive correlation between the TT-TG distance and the AT was found. An increase in external torsion of the proximal tibial or an increase in internal torsion of the distal femur increases the TT-TG distance. For a correct interpretation of the TT to trochlear groove distance, we propose that the axial alignment should be included in the regular analysis of patellofemoral disease.

A Novel Approach to Lower-limb Axial Alignment Analysis: A CT Study.

To analyze the torsion of the lower extremities in a healthy cohort and to determine the contribution of different segments of the femur and tibia to the torsion of both bones. METHODS: In this cross-sectional study, 32 patients with nonjoint or bone-related symptoms were analyzed by CT angiography. Lower-limb torsion, femoral torsion, proximal femoral torsion, femoral shaft torsion, distal femoral torsion, tibial torsion, proximal tibial torsion, and distal tibial torsion were measured. RESULTS: The median total limb torsion was 25° external torsion, with the median femoral torsion being -9° and the median tibial torsion 30°. Both femoral metaphyses had internal torsion, with the internal torsion of the proximal metaphysis being approximately three times greater than that of the distal femoral metaphysis. The shaft was found to compensate with an external torsion of approximately two-thirds of the internal torsion of both femoral metaphyses. The proximal metaphysis of the tibia accounted for approximately one-third of the external torsion, with the segment from the distal to the tibial tubercle accounting for the remaining two-thirds of the tibial torsion. CONCLUSIONS: The diaphysis and distal metaphysis are the major contributors to external torsion of the tibia, whereas the proximal metaphysis is the major contributor to the internal torsion of the femur.

Gonyautoxins: First evidence in pain management in total knee arthroplasty.

Improvements in pain management techniques in the last decade have had a major impact on the practice of total knee arthroplasty (TKA). Gonyautoxin are phycotoxins, whose molecular mechanism of action is a reversible block of the voltage-gated sodium channels at the axonal level, impeding nerve impulse propagation. This study was designed to evaluate the clinical efficacy of Gonyautoxin infiltration, as a long acting pain blocker in TKA. Fifteen patients received a total dose of 40 µg of Gonyautoxin during the TKA operation. Postoperatively, all patients were given a standard painkiller protocol: 100 mg of intravenous ketoprofen and 1000 mg of oral acetaminophen every 8 hours for 3 days. The Visual Analog Scale (VAS) pain score and range of motion were recorded 12, 36, and 60 hours post-surgery. All patients reported pain of 2 or less on the VAS 12 and 36 hours post-surgery. Moreover, all scored were less than 4 at 60 hours post-surgery. All patients achieved full knee extension at all times. No side effects or adverse reactions to Gonyautoxin were detected in the follow-up period. The median hospital stay was 3 days. For the first time, this study has shown the effect of blocking the neuronal transmission of pain by locally infiltrating Gonyautoxin during TKA. All patients successfully responded to the pain control. The Gonyautoxin infiltration was safe and effective, and patients experienced pain relief without the use of opioids.