Reliability of pre-resection ligament tension assessment in imageless robotic assisted total knee replacement.

BACKGROUND: Ligament tension balance is a major determinant for the success of total knee replacement (TKR). The present study aimed at determining the inter-rater and intra-rater reliability in performing ligament tension assessment using an imageless robotic-assisted TKR. METHODS: Twenty-four knees in 21 patients who received robotic-assisted TKR for end-stage varus osteoarthritis were examined. Three orthopedic specialists and six orthopedic trainees participated in the operations. Data from the ligament tension assessment were collected during the operations. RESULTS: For the inter-rater reliability, "extension medial" and "flexion medial" had excellent reliability whilst "extension lateral" and "flexion lateral" had good-to-excellent reliability. For the intra-rater reliability, "extension medial" showed excellent reliability, "extension lateral" and "flexion medial" showed good-to-excellent reliability, and "flexion lateral" showed moderate-to-excellent reliability. CONCLUSIONS: Robotic-assisted technology provides a reliable solution to improve ligament tension assessment. All ligament tension assessments with the use of the technology could demonstrate at least good-to-excellent reliability except for the intra-rater reliability of "flexion lateral".

[Total knee replacement in patients under 60 years with high functional demand: functional outcomes and return to sports after an average 2-year follow-up]. / Reemplazo total de rodilla en pacientes menores de 60 años con demanda funcional elevada: resultados funcionales y retorno al deporte después de un promedio de dos años de seguimiento.

INTRODUCTION: a common concern in presurgical medical appointment of total knee replacement medical appointment is return to exercise. The purpose of this study was to analyze functional results and return to sport in patients under 60 years of age after this surgery. MATERIAL AND METHODS: we retrospectively analyzed 41 total knee replacements in 36 athletic patients (average age: 53 years [46-60]). Average follow-up of two years (6 months-5 years). Diagnoses: 37 osteoarthritis, three sequelae of Rheumatoid Arthritis, 1 extra-articular deformity. Functional and radiographic outcomes assessed using modified Knee Society and High Activity Arthroplasty Scores. RESULTS: average improvement from 31.95 to 91.61 in KSS and average from 7.95 to 13.73 in HAAS. Return to sport in 3.5 months average (range 2-6 months). Three patients did not return to sport. CONCLUSIONS: we consider that delaying surgery in these patients will cause progression in their osteoarthritis pathology and cessation of their sports activities. This makes the surgical technique difficult in addition to reducing the patient's physical performance. Analyzing the survival rate of implants in young patients, more than 80% is reported in a 25-year follow-up.

INTRODUCCIÓN: una inquietud frecuente en consultas prequirúrgicas de reemplazo total de rodilla es el regreso al ejercicio. El propósito de este estudio fue analizar resultados funcionales y retorno al deporte en pacientes menores de 60 años posterior a esta cirugía. MATERIAL Y MÉTODOS: analizamos retrospectivamente 41 reemplazos totales de rodilla en 36 pacientes deportistas (edad promedio: 53 años [46-60]). Seguimiento promedio de dos años (6 meses-5 años). Diagnósticos: 37 gonartrosis, tres secuelas de artritis reumatoidea, una deformidad extraarticular. Resultados funcionales y radiográficos evaluados mediante Knee Society modificado y High Activity Arthroplasty Score. RESULTADOS: mejoría promedio de 31.95 a 91.61 en KSS y promedio de 7.95 a 13.73 en HAAS. Retorno al deporte en 3.5 meses promedio (rango: 2-6 meses). Tres pacientes no retornaron al deporte. CONCLUSIONES: consideramos que el retraso de la cirugía en estos pacientes producirá progresión en su patología artrósica y cese de sus actividades deportivas. Esto dificulta la técnica quirúrgica además de disminuir el rendimiento físico del paciente. Analizando la tasa de supervivencia de implantes en pacientes jóvenes, se reporta más de 80% en seguimientos de 25 años.

The effect of kinesio taping on joint range of motion and balance in total knee replacement patients.

We adopted a within-subjects quasi-experimental approach to assess the impact of kinesio taping (KT) on joint range of motion (ROM), static balance, and dynamic balance. The research subjects were 15 patients who had, within the previous 3 weeks, undergone total knee replacement (TKR) by an orthopedic surgeon in 2022. We measured the ROM, static balance, and dynamic balance of the knee joint before and after applying KT. We then compared the pre- and post-tape measurements to assess the effects of KT on joint function and balance. The ROM of the knee joint was measured using a goniometer in the supine position before the KT application. The static and dynamic balance were assessed using a balance assessment device by measuring the sway area and length of the center of gravity during the measurement period. The effects of KT on the ROM and static and dynamic balance of the knee joint were investigated. The differences in joint ROM and static and dynamic balance between pre- and post-KT applications were analyzed using a paired-sample t-test. This study found that the ROM of the knee joint was significantly increased after applying KT. For static and dynamic balance, both the sway area and length of the center of gravity decreased after applying KT, indicating a significant improvement in static and dynamic balance. KT, when combined with standard physiotherapy, can be a useful therapeutic approach for TKR patients, effectively enhancing joint ROM and balance function.

No difference in clinical outcomes when retaining or sacrificing the posterior cruciate ligament in medial congruent total knee replacement. A retrospective study.

PURPOSE: The aim of this study is to evaluate the effect of retaining or sacrificing the posterior cruciate ligament (PCL) in patients who undergo primary total knee replacement (TKR) with the medial congruent (MC) implant. METHODS: This retrospective study looks at patients who underwent TKR with the MC implant. Comparison was made between the group with the PCL sacrificed (MC-PCLS) and the group with the PCL retained (MC-PCLR). Range of motion (ROM), Oxford knee score (OKS), Knee society knee score (KS-KS) and Knee society function score (KS-FS) were recorded. RESULTS: The study identified 76 patients. 50 in the MC-PCLS group and 26 in the MC-PCLR group. Both groups had similar patient demographics. Three months postoperatively, OKS and KS-KS had significant improvement. However, there was significant improvement in KS-FS score in the MC-PCLS group but not the MC-PCLR group (MC-PCLR: 33 ± 17, p = 0.07; MC-PCLS: 19 ± 24, p = 0.01). Twelve months postoperatively, the OKS continued to improve significantly for both groups, while the KS-FS and KS-KS scores appeared to stagnate. The ROM continued to improve significantly for the MC-PCLR group but not the MC-PCLS group (MC-PCLR: 7 ± 9, p = 0.03; MC-PCLS: 4 ± 9, p = 0.30). Both groups were similar in ROM, OKS and KSS scores at both the 3 and 12 month post-operative period. CONCLUSION: There is no difference in post-operative outcomes with the PCL retained or sacrificed. As such, surgeons can consider routinely sacrificing the PCL for easier balancing of the knee and shorter surgical time.

Carbon savings associated with changing surgical trends in total knee arthroplasty in England: a retrospective observational study using administrative data.

BACKGROUND: Best practice pathways for common surgical procedures, including total knee arthroplasty (TKA), have the potential to improve patient outcomes and reduce carbon emissions. We aimed to estimate the reduction in carbon emissions due to changing trends in the care of patients undergoing TKA in England. METHODS: This was a retrospective analysis of Hospital Episode Statistics data from 1 April 2013 to 31 March 2022 on adults undergoing elective primary TKA in England. The carbon footprint for each patient was calculated using carbon factors for multiple steps in the pathway, including ipsilateral knee arthroscopies in the year preceding the TKA, outpatient attendances, the index TKA, revisions of the TKA performed within 180 days of the index procedure, length of hospital stay and emergency readmissions. RESULTS: A total of 648,861 TKA operations were identified. Over the study period, the median length of stay reduced from four to three days, the proportion of patients undergoing ipsilateral knee arthroscopies performed within a year before TKA surgery fell from 5.9% to 0.5% and the number of early revisions and emergency readmissions also fell. The per-patient carbon footprint reduced from 378.8kgCO2e to 295.2kgCO2e over this time. If all the study patients had the same carbon footprint as the average patient in 2021/2022, 32.4kilotons CO2e would have been saved, enough to power 29,509 UK homes for one year. CONCLUSIONS: Practices that were introduced primarily to improve patient outcomes can contribute to a reduction in the carbon footprint.

Comparison of Six-Week, Three-Month, and One-Year Postoperative Clinical Results of Kinematic and Mechanical Alignment in Primary Medial Pivot Total Knee Arthroplasty.

BACKGROUND: Total knee replacement (TKR) is a common surgical solution for severe osteoarthritis. Kinematic alignment (KA) and mechanical alignment (MA) are two popular techniques. There is ongoing debate over the optimal method, influenced by varying long-term results and a scarcity of data on short-term postoperative outcomes. Early evaluation of these techniques is vital for improving rehabilitation outcomes and ensuring patient satisfaction.  Methods: This study retrospectively analyzed outcomes from 71 KA-TKRs and 85 MA-TKRs performed between 2019 and 2021. Knee flexion, visual analog scale (VAS) scores, EuroQol-5d (EQ-5d) quality of life measures, and dependence on walking aids were evaluated. Evaluations were conducted at baseline, six-weeks, three-months, and 12-months postoperatively using two-sample t-tests for continuous data and Pearson's chi-squared test for categorical data. RESULTS: At six-weeks and three-months postoperatively, the KA group exhibited significantly better outcomes in knee flexion (98.6° vs. 90.2° at six-weeks; 114.7° vs. 94.2° at three-months), pain management, and reduced walking aids compared to the MA group. By 12-months, these differences were no longer significant, with both groups showing comparable results in knee flexion, pain scores, and patient-reported outcomes.  Conclusion: KA offers substantial short-term advantages over MA for pain relief, increased knee flexion, and independence from walking aids. However, these benefits do not persist at one-year post-surgery, indicating a convergence of outcomes between the two techniques. Larger studies with extended follow-ups are required to determine the long-term implications of these alignment strategies.

Hypoallergenic Knee Implant Usage and Clinical Outcomes: Are They Safe and Effective?

Background: One of the most debated topics in modern total knee arthroplasty (TKA) is the impact of metal hypersensitivity (MH) as a potential cause of prosthesis failure. Implanting hypoallergenic prostheses to avoid potential problems in suspected cases of MH is one treatment option that can be used in such cases. However, their long-term clinical safety and efficacy are not well proven. Methods: All literature relevant to modern hypoallergenic implants were reviewed and summarized to provide a comprehensive synopsis. In addition, a detailed literature search was performed on PUBMED, MEDLINE, and Google Scholar to identify all the clinical studies reporting outcomes for hypoallergenic knee implants. Our search was confined to those studies published as full manuscripts in the English language from July 2018 to July 2023. Results: To minimize the risk of MH, new implant variants have been developed which are either under clinical evaluation or in routine clinical use. These include conventional metal implants with protective coatings (mono- or multilayer) and metal-free implants. However, there is insufficient clinical data to confirm the rationale and effectiveness of using these "hypoallergenic" TKA implants. Conclusions: Published studies and arthroplasty registry data analyses indicate no significant differences between hypoallergenic and standard TKAs with overall good survival rates. In the future, further high-quality studies are needed to better understand the complexity of this subject.

Do octogenarian patients undergoing total knee replacement return to physical activity? / ¿Los pacientes octogenarios sometidos a reemplazo total de rodilla regresan a la actividad física?

BACKGROUND AND OBJECTIVES: It has been shown that total knee replacement improves functional capacity and physical activity; however, the influence of age remains unclear. The objective is evaluate the pre and postoperative physical activity measured with the Knee Society Score (KSS) score and the Tegner score. MATERIALS AND METHODS: A retrospective cohort analysis was conducted on patients who underwent total knee replacement (TKR) between January 2016 and December 2019 at our institution. Demographic variables (age, sex, and body mass index), activities of daily living, age-adjusted Charlson Comorbidity Index, American Society of Anesthesiologists score, the Knee Society Score (KSS) in its clinical (KSSc) and functional (KSSf) subscales, the Tegner functional scale, activity variables from the 2011 KSS version, and pain assessment using the visual analog scale were collected. Differences in these variables were analyzed between two age groups: group A (between 65 and 79 years old) and group B (80 years or older). RESULTS: A total of 450 patients were evaluated (group A=245, group B=167). Group A showed a Tegner improvement of 1.19 (95% CI: 1.06-1.31), whereas group B averaged 0.61 (95% CI: 0.43-0.80) (P<.001). Age >80 was an independent risk factor for less Tegner improvement. In KSSc, group A improved by 43 points (95% CI: 40.82-46.14), while group B showed a greater increase of 53 points (95% CI: 49.74-57.80). Adjusted for confounders, those>80 showed significantly higher KSSc improvement (12.8 points). For KSSf, group A improved by 33.91 points (95% CI: 31.07-36.75), and group B by 15.57 points (95% CI: 11.78-19.35). Adjusted for confounders, patients >80 had less improvement than those <80 (19 points). CONCLUSIONS: Patients who underwent TKR experienced improvements in physical and functional activity parameters. While these improvements were seen in the entire population, they were most notable in patients younger than 80 years.

[Return to activity and return to sports after total knee replacement]. / "Return-to-activity" und "return-to-sport" nach endoprothetischer Versorgung des Kniegelenks.

BACKGROUND: Total knee arthroplasty (TKA) is one of the most common and successful operations in the field of orthopaedics, with a steadily increasing number of patients. However, as the patient population becomes younger, expectations regarding the outcome of the surgery are also changing. In addition to pain reduction and improved mobility, the longevity of the implant and the recovery of (everyday) activity in general (return-to-activity, RtA) and sporting activity in particular (return-to-sports, RtS) are becoming increasingly important. STATE OF THE STUDY: RtS with a tendency towards low-impact sports seems generally possible but is highly dependent on the individual characteristics of the patient. Despite comprehensive studies on treatment with TKA, there are no systematic studies and reliable conclusions on the key factors that enable patients to return to sports after TKA. Any recommendation by the responsible surgeons remains dependent on their subjective experience due to the lack of standardized implementation of an RtA/RtS assessment and the necessary long-term follow-up observation under control of patient-related confounding factors.

Prospective randomized study on the effect of concurrent bone filling of tibial peg holes in cementless total knee arthroplasty.

BACKGROUND: In total knee arthroplasty (TKA), cementless fixation is initially weaker than cement fixation. This study aimed to examine whether filling the tibial peg holes with bone improves initial fixation strength in cementless TKA. METHODS: This prospective, comparative study examined 88 joints in 66 patients randomized to the bone filling (48 joints) or conventional group (no bone filling; 40 joints). All patients underwent TKA with the NexGen® trabecular metal modular tibial component. In the bone filling group, resected cancellous bone was filled into the peg holes before insertion of the tibial component. We performed clinical and plain radiographic evaluations after the operation and measured bone mineral density (BMD) at five sites below the component at 1, 3, 6, and 12 months postoperatively. RESULTS: Operative time and clinical evaluations were not significantly different. Plain radiography showed significant longitudinal thickening of the trabecula below the peg (P<0.05) and decreased occurrence of reactive lines (P=0.07) in the bone filling group compared with the conventional group. BMD was significantly higher in the bone filling group in the medial region below the peg at 1, 3, and 6 months and in the central region at 1 and 3 months (all P<0.05). CONCLUSIONS: When using the NexGen trabecular metal modular tibial component, concurrent peg hole bone filling increases the initial component fixation strength. Possible effects on long-term stabilization warrant further study.

A case of recurrent proximal femoral fracture after open reduction and internal fixation with bilateral locking plates for a Rorabeck type II periprosthetic fracture.

INTRODUCTION AND IMPORTANCE: Periprosthetic distal femur fractures (PDFFs) are rare complications that may occur during or after total knee arthroplasty (TKA). The incidence of PDFFs is increasing. Plate internal fixation has demonstrated positive results. However, there is limited research available on the recurrence of periimplant fractures following open reduction and internal fixation with bilateral locking plates. CASE PRESENTATION: A 70-year-old female patient was diagnosed with a Rorabeck type II fracture. Based on the patient's physical condition and available surgical options, minimally invasive open reduction, bilateral plate fixation, and allograft artificial bone grafting were chosen. The postoperative recovery was successful. However, the patient experienced a fall 2 months after the surgery, resulting in a proximal femoral fracture. After considering the patient's condition and family preferences, conservative treatment was ultimately decided upon. CLINICAL DISCUSSION: Minimally invasive bilateral Locking Compression Plate (LCP) as a surgical approach can effectively reduce surgical risks prior to the procedure. Careful selection of screws and the use of C-arm fluoroscopy during plate contouring and fixation are essential to prevent screw penetration through the contralateral cortex. Treatment outcomes were not impacted in patients with normal bone mass; however, in this particular case, the patient had severe osteoporosis, significantly increasing the risk of refracture. It is crucial to improve postoperative monitoring and raise awareness about safety among patients and their families. CONCLUSION: The management of periprosthetic distal femur fractures (PDFFs) is influenced by the type of fracture and bone quality. Mechanical stability and stress dispersion of internal fixation are key factors to consider. In the perioperative setting, involving experienced clinicians is essential to reduce the risk of secondary injuries that may impact treatment outcomes, especially when choosing screws for fixation in patients with low bone density.

Preoperative vagal activity predicts clinical outcomes after total knee replacement.

Total knee replacement (TKR) surgery carries with it significant surgical trauma and activates complex inflammatory pathways, which initially assist healing. However, impaired regulation of inflammatory pathways can cause tissue damage and postoperative complications. The vagus nerve regulates inflammation, the activity of which is indexed by heart-rate variability (HRV), which predicts postoperative pain, longer hospitalization and improved recovery during the postoperative period. The present study examined the relationship between presurgical HRV, inflammation and complications after TKR. The present study assessed data from 41 patients undergoing TKR. A retrospective design was used, where preoperative electrocardiograms were scanned to determine HRV. Outcome measures included inflammation [C-reactive protein (CRP) levels] over four postoperative days, length of stay (LOS), and complications. Preoperative HRV predicted the trajectory of postoperative CRP levels. The low HRV group demonstrated higher overall postoperative CRP and a longer time to recover than patients with high HRV. Furthermore, the magnitude of inflammatory decline between postoperative days two and four was associated with LOS. However, HRV did not predict postoperative complications. In conclusion, patients with lower presurgical vagal activity had a worse postoperative inflammatory profile than those with high vagal tone. In the age of personalized medicine, such findings may have implications for identifying and preparing patients before surgery.

A Rare Presentation of Pseudoaneurysm of the Popliteal Artery After Total Knee Replacement: A Case Report and Review of the Literature.

Total knee replacement (TKR) is a common successful surgery in terms of the outcomes. The common complications of TKR are joint infection, deep venous thrombosis (DVT), wound complication, and postoperative knee instability. Arterial complications are not common. We are presenting a 61-year-old man who underwent left TKR. Upon postoperative regular follow-up, the patient developed symptoms and clinical presentation for DVT. However, initial duplex ultrasonography was negative for DVT. Repeated duplex ultrasonography showed a pseudoaneurysm of the popliteal artery, and the diagnosis was confirmed with computed tomography (CT) angiography. Pseudoaneurysm of the popliteal artery is a rare complication following primary TKR. Our patient underwent endovascular angioplasty and stenting of the pseudoaneurysm of the left popliteal artery. The patient completed three years and six months of follow-up with an uneventful course. We selected to share our experience of this rare case because pseudoaneurysm of the popliteal artery is a rare complication after TKR, which is usually present with symptoms that can mimic DVT, such as acute lower limb swelling, calf muscle pain, and pain with passive ankle dorsiflexion. Duplex ultrasonography is the preferred first diagnostic tool, and CT angiography (CTA) is needed to confirm the diagnosis and to plan treatment. Treatment with endovascular stent proved to be safe and successful with no infection risk or need for modifying rehabilitation protocol after more than three years of follow-up.

Mid-Term Clinical and Radiological Changes in the Ankle Joint in Varus Knee Osteoarthritis Following Total Knee Arthroplasty.

Background/Objectives: In patients with varus knee osteoarthritis, compensatory changes occur in the foot and ankle joints to compensate for the varus deformity of the knee. The aim of the study was to investigate the changes in the ankle of patients whose knee alignment was corrected with total knee arthroplasty (TKA) and to explore the clinical implications of these findings. Methods: In this retrospective observational study, we analyzed 204 knees of 179 patients who had regular follow-ups out of 431 patients who underwent TKA for varus knee osteoarthritis between January 2019 and July 2021. Patient demographics, body mass index, follow-up time, and radiographs were studied. The hip-knee-ankle (HKA) angle, joint line convergence angle (JLCA), talar tilt (TT) angle, ground talar dome (GT) angle, ground tibia plafond (GP) angle, and the American Orthopaedic Foot & Ankle Society (AOFAS) score were assessed preoperatively and at the last follow-up. Results: A total of 204 knees of 179 patients with a mean follow-up time of 32.50 ± 6.68 months were evaluated. It was found that the change in the HKA had a positive effect on the AOFAS score and a negative effect on the TT, GT, and GP angles. While the clinical score improved in 82 patients, it worsened in 8 patients. The age difference between the groups whose AOFAS score improved and worsened was statistically significant. Conclusions: The correction of the varus malalignment in the knee was shown to also improve the compensatory valgus in the foot and ankle over the mid-term, with a statistically significant improvement in the patients' clinical ankle scores.

[Prehabilitation before total knee arthroplasty]. / Prähabilitation vor Knieendoprothetik.

BACKGROUND: Prehabilitation before knee joint replacement surgery is gaining increasing importance due to the rising prevalence of knee osteoarthritis. The aim is to optimize the preoperative condition to improve postoperative recovery and reduce complications. MATERIALS AND METHODS: This review is based on a systematic literature search in the databases Medline, Cochrane Library, and Web of Science on the topic of prehabilitation in knee joint replacement. RESULTS: The current evidence shows heterogeneous results regarding the effectiveness of prehabilitation before knee joint replacement; some studies report improved postoperative outcomes such as reduced pain, increased function, and shorter hospital stays through preoperative training measures, while others found no significant differences. Additional preoperatively modifiable risk factors such as reduced physical fitness, substance abuse, nutritional status, comorbidities, and psychological factors should already be addressed during prehabilitation. Digital therapy and education measures offer a promising solution for the implementation of prehabilitation programs and are well received by patients. CONCLUSION: Overall, the evidence for preoperative training before knee joint replacement remains heterogeneous. Despite positive indications, evidence on exercise content, duration, frequency, and setting remains incomplete, requiring a critical review of current meta-analyses and systematic reviews. Modern prehabilitation before knee joint replacement should include musculoskeletal training and address preoperative risk factors to improve postoperative outcomes.

Thyroid Diseases After Total Knee Replacement: A Multi-center, Propensity-score-matched Cohort Study.

BACKGROUND/AIM: Thyroid diseases are prevalent endocrine disorders that significantly affect overall health. Although the impact of pre-existing thyroid dysfunction on total knee replacement (TKR) outcomes has been studied, the potential for TKR to increase the risk of developing thyroid disorders remains unexplored. PATIENTS AND METHODS: We examined electronic medical records from a large U.S. research network in the TriNetX research network. The study focused on patients with osteoarthritis, comparing those who had total knee replacement surgery (TKR) between 2005 and 2018 to a non-TKR group who did not have the surgery. Propensity score matching was employed to control for critical confounders. The hazard ratios (HRs) for the risk of thyroid diseases in TKR patients versus non-TKR controls were assessed. RESULTS: Post-matching, the TKR cohort demonstrated a significantly higher risk of developing thyroid diseases compared to the non-TKR cohort (unadjusted HR=1.218, 95%CI=1.169-1.269). This elevated risk persisted after adjusting for confounders (adjusted HR=1.126, 95%CI=1.061-1.196). Stratification analysis indicated that female TKR patients and those aged ≥65 years were at higher risk of developing thyroid diseases than their respective control groups. CONCLUSION: This study suggests a potential link between TKR and an increased risk of thyroid diseases, particularly among older adults and females. Potential mechanisms include inflammatory processes, surgical stress, autoimmune responses, and pharmacological effects. Healthcare providers should be vigilant in monitoring and managing thyroid dysfunction in TKR patients. Further research is necessary to elucidate the underlying mechanisms and develop preventive strategies.

Effect of Transcutaneous Electrical Nerve Stimulation on Patients with Total Knee Replacement: A Randomized Controlled Trial.

PURPOSE: The aim of this study was to determine the effect of transcutaneous electrical nerve stimulation (TENS) on pain, functionality, quality of life, and analgesic consumption in patients undergoing TKR. DESIGN: A single center, randomized controlled trial. METHODS: A total of 52 participants were randomly assigned to the intervention (n = 26) and control (n = 26) groups. The intervention group was exposed to conventional TENS. Data were collected with a Patient Identification Form, the Visual Analogue Scale (VAS), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Quality of Life Scale (SF-36), and the Analgesic Tracking Form. RESULTS: VAS and WOMAC scores significantly decreased in the intervention group, over time, while they increased in the control group. SF-36 scores significantly increased in the intervention group over time. It was determined that analgesic consumption was significantly lower in the intervention group than in the control group. CONCLUSIONS: TENS significantly reduced pain and increased functionality and quality of life. Our findings suggest that TENS may be an effective adjunctive analgesic therapy in patients receiving TKR; however, more testing is needed in larger and more heterogeneous populations. CLINICAL IMPLICATIONS: Nurses can provide effective postoperative pain control in patients undergoing TKR, increase functionality, accelerate the healing process, and improve their quality of life by using TENS, a non-pharmacological treatment method, in the perioperative period.

Computational biomechanical study on hybrid implant materials for the femoral component of total knee replacements.

Multifunctional materials have been described to meet the diverse requirements of implant materials for femoral components of uncemented total knee replacements. These materials aim to combine the high wear and corrosion resistance of oxide ceramics at the joint surfaces with the osteogenic potential of titanium alloys at the bone-implant interface. Our objective was to evaluate the biomechanical performance of hybrid material-based femoral components regarding mechanical stress within the implant during cementless implantation and stress shielding (evaluated by strain energy density) of the periprosthetic bone during two-legged squat motion using finite element modeling. The hybrid materials consisted of alumina-toughened zirconia (ATZ) ceramic joined with additively manufactured Ti-6Al-4V or Ti-35Nb-6Ta alloys. The titanium component was modeled with or without an open porous surface structure. Monolithic femoral components of ATZ ceramic or Co-28Cr-6Mo alloy were used as reference. The elasticity of the open porous surface structure was determined within experimental compression tests and was significantly higher for Ti-35Nb-6Ta compared to Ti-6Al-4V (5.2 ± 0.2 GPa vs. 8.8 ± 0.8 GPa, p < 0.001). During implantation, the maximum stress within the ATZ femoral component decreased from 1568.9 MPa (monolithic ATZ) to 367.6 MPa (Ti-6Al-4V/ATZ), 560.9 MPa (Ti-6Al-4V/ATZ with an open porous surface), 474.9 MPa (Ti-35Nb-6Ta/ATZ), and 648.4 MPa (Ti-35Nb-6Ta/ATZ with an open porous surface). The strain energy density increased at higher flexion angles for all models during the squat movement. At ∼90° knee flexion, the strain energy density in the anterior region of the distal femur increased by 25.7 % (Ti-6Al-4V/ATZ), 70.3 % (Ti-6Al-4V/ATZ with an open porous surface), 43.7 % (Ti-35Nb-6Ta/ATZ), and 82.5% (Ti-35Nb-6Ta/ATZ with an open porous surface) compared to monolithic ATZ. Thus, the hybrid material-based femoral component decreases the intraoperative fracture risk of the ATZ part and considerably reduces the risk of stress shielding of the periprosthetic bone.

Comparison of the effect of combined usage of povidone-iodine irrigation and topical vancomycin powder to the use of povidone-iodine irrigation alone on the periprosthetic joint infection incidence rate in patients undergoing primary total hip and knee arthroplasty: a protocol for multicenter prospective randomized clinical trial.

BACKGROUND: With the increasing number of joint replacement surgeries, periprosthetic joint infection (PJI) has become a significant concern in orthopedic practice, making research on PJI prevention paramount. Therefore, the study will aim to compare the effect of combined usage of povidone-iodine and topical vancomycin powder to the use of povidone-iodine alone on the PJI incidence rate in patients undergoing primary total hip (THA) and total knee arthroplasty (TKA). METHODS: The prospective randomized clinical trial will be conducted in two independent voivodeship hospitals with extensive experience in lower limb arthroplasties. The studied material will comprise 840 patients referred to hospitals for primary THA or TKA. The patients will be randomly allocated to two equal groups, receiving two different interventions during joint replacement. In group I, povidone-iodine irrigation and consecutively topical vancomycin powder will be used before wound closure. In group II, only povidone-iodine lavage irrigation will be used before wound closure. The primary outcome will be the incidence rate of PJI based on the number of patients with PJI occurrence within 90 days after arthroplasty. The occurrence will be determined using a combined approach, including reviewing hospital records for readmissions and follow-up phone interviews with patients. The infection will be diagnosed based on Musculoskeletal Infection Society criteria. The chi-square test will be used to compare the infection rates between the two studied groups. Risk and odds ratios for the between-groups comparison purposes will also be estimated. Medical cost analysis will also be performed. DISCUSSION: A randomized clinical trial comparing the effect of combined usage of povidone-iodine irrigation and vancomycin powder to the use of povidone-iodine irrigation alone in preventing PJIs after primary arthroplasty is crucial to advancing knowledge in orthopedic surgery, improving patient outcomes, and guiding evidence-based clinical practices. TRIAL REGISTRATION: ClinicalTrials.gov NCT05972603 . Registered on 2 August 2023.

Mid-term outcomes using a 'kinematic retaining' total knee replacement - A multicentre prospective study at five years follow-up.

Background: Although total knee replacement (TKR) surgery has succeeded in improving pain and deformity, a proportion of patients remain incompletely satisfied with their outcome. This prospective study aims to assess the survivorship, clinical, and radiological outcomes using a novel 'kinematic retaining' (KR) implant. Methods: 156 patients underwent TKR surgery for primary osteoarthritis using the Physica KR implant at three European Centres. Patients were followed up for five years using both radiographic and clinical evaluations. Results: Within 6 months post-operatively, 79.4% and 85.9% had good-excellent clinical and functional KSS values, this was maintained to 76.9% and 79.5% at five years. Mean Knee Society Score (KSS) improvement at 5 years was 32.8 (from 23 to 40) and 37.4 (from 30 to 50) (p < 0.01). All Knee Injury and Osteoarthritis Outcome Score (KOOS) sub-scores showed statistically significant improvement from before surgery at a mean of 34.7 (SD ± 16.1) to a mean of 86.6 (SD ± 16.1) at five years. The mean Oxford Knee Score (OKS) was 43.7 (±5.6), with over 80% of the patients having a good-excellent outcome at five years. OKS improved significantly by six weeks after surgery (p < 0.01) and remained constant throughout the 5-year follow-up. Visual Analogue Score (VAS) Satisfaction scores improved significantly after the post-operative time point of six weeks. From 1 year to 5 years, the average VAS was over 85 mm. The Forgotten Joint Score (FJS) increased from 64.5 at 1 year to 79.2 at 5 years after surgery (p < 0.01). No progressive adverse radiographic features were noted. Two patients were revised during the study period: one for infection and the other for aseptic loosening. Conclusions: This novel 'kinematic retaining' knee prosthesis has shown exceptional clinical and patient-reported improvements, with a remarkable 99.4% survivorship (95.5-99.9) at five years.