Medial Compartment Knee Research Articles

Inpatient cost comparison of total and unicompartmental knee arthroplasty in patients with medial compartmental osteoarthritis using time-driven activity-based costing.

Using time-driven activity-based costing (TDABC), we sought to compare the total facility costs, comprising supply and personnel costs during the episode of care for the index procedure, in patients with isolated medial compartmental knee osteoarthritis (OA) undergoing unicompartmental knee arthroplasty (UKA) versus total knee arthroplasty (TKA). We conducted a retrospective analysis of 100 UKAs and 100 TKAs from 2019 to 2022. From a larger sample of 4899 TKAs and 137 UKAs, patients with isolated medial OA (Kellgren-Lawrence Grade <2 in other compartments) were radiographically identified. Demographic data included age, sex and body mass index, with comorbidities controlled using the Charlson comorbidity index. Facility costs were calculated using TDABC and standardized in cost units (CUs), a metric for comparing costs across procedures. Multiple regression analysis was used to assess the independent effect of TKA versus UKA on facility costs. TKA patients had similar operative times (TKA vs. UKA: 1.01×, p = 0.783) and supply costs (1.00×, p = 0.866), where 'x' denotes the relative cost ratio. However, TKA was associated with higher personnel costs (260.0 vs. 222.5 CUs [1.17×], p < 0.001) and total facility costs, both including (706.3 vs. 667.5 CUs [1.06×], p = 0.007) and excluding implants (353.8 vs. 312.5 CUs [1.13×], p < 0.001). Adjusted for demographics and comorbidities, TKA had increased facility costs, including (32.2 CUs, 95% confidence interval [CI]: 2.9-61.5, p = 0.031) and excluding implants (37.8 CUs, 95% CI: 15.2-60.3, p = 0.001). TDABC analysis revealed higher total facility costs for the index procedure in TKA, suggesting UKA may be a cost-saving alternative for isolated medial compartment knee OA. Level III, retrospective comparative study.

Population-based in silico modeling of anatomical shape variation of the knee and its impact on joint loading in knee osteoarthritis.

Anatomical knee joint features and osteoarthritis (OA) severity are associated, however confirming causals link to altered knee loading is challenging. This study leverages statistical shape models (SSM) to investigate the relationship between joint shape/alignment and knee loading during gait in knee OA(KOA) patients to understand their contribution to elevated medial knee loading in OA. Musculoskeletal (MSK) models were created for the mean as well as the first eightSSM principal modes of variation (-3,-2,-1, +1, +2, +3 standard deviations for each mode) and used as input to a MSK modeling framework. Using an identical KOA gait pattern (i.e., joint kinematics and ground reaction forces), we ran simulations for each MSK model and evaluated medial compartment loading magnitude and contact distribution at the instant of first and second peak of knee joint loading. An increase in external rotation, posterior tibia translation and a decrease in medial joint space and medial femoral condylar size predisposed the medial compartment knee joint to overloading during gait. This was coupled with an anterior and medial shift in contact location with increasing external rotated tibial position and increasing posterior tibial translation with respect to the femur. Next, results also highlighted a posterior shift of the medial compartment loading location with decreasing medial joint space. This study provides important population-based insights on how knee shape and alignment predispose individuals with KOA to elevated medial compartmental knee loading. This information can be crucial in assessing the risk for medial KOA development and progression.

Stochastic lattice-based porous implant design for improving the stress transfer in unicompartmental knee arthroplasty

BackgroundUnicompartmental knee arthroplasty (UKA) has been proved to be a successful treatment for osteoarthritis patients. However, the stress shielding caused by mismatch in mechanical properties between human bones and artificial implants remains as a challenging issue. This study aimed to properly design a bionic porous tibial implant and evaluate its biomechanical effect in reconstructing stress transfer pathway after UKA surgery.MethodsVoronoi structures with different strut sizes and porosities were designed and manufactured with Ti6Al4V through additive manufacturing and subjected to quasi-static compression tests. The Gibson-Ashby model was used to relate mechanical properties with design parameters. Subsequently, finite element models were developed for porous UKA, conventional UKA, and native knee to evaluate the biomechanical effect of tibial implant with designed structures during the stance phase.ResultsThe internal stress distribution on the tibia plateau in the medial compartment of the porous UKA knee was found to closely resemble that of the native knee. Furthermore, the mean stress values in the medial regions of the tibial plateau of the porous UKA knee were at least 44.7% higher than that of the conventional UKA knee for all subjects during the most loading conditions. The strain shielding reduction effect of the porous UKA knee model was significant under the implant and near the load contact sites. For subject 1 to 3, the average percentages of nodes in bone preserving and building region (strain values range from 400 to 3000 μm/m) of the porous UKA knee model, ranging from 68.7 to 80.5%, were higher than that of the conventional UKA knee model, ranging from 61.6 to 68.6%.ConclusionsThe comparison results indicated that the tibial implant with designed Voronoi structure offered better biomechanical functionality on the tibial plateau after UKA. Additionally, the model and associated analysis provide a well-defined design process and dependable selection criteria for design parameters of UKA implants with Voronoi structures.

Influence of Internal and External Foot Rotation on Peak Knee Adduction Moments and Ankle Moments during Gait in Individuals with Knee Osteoarthritis: A Cross-Sectional Study.

The aim of the study was to verify the effects of foot progression angle (FPA) modification during walking on the internal moments of the ankle and knee joints in individuals with knee osteoarthritis (OA). Biomechanical changes such as increased knee adduction moment (KAM) during walking are known to be involved in the development and severity of knee OA. Although various FPA modifications during gait have been applied to reduce peak KAM, few studies have investigated the effects of applying toe-in or toe-out walking modifications for knee OA on peak KAM and three-dimensional (3D) moments of the ankle joint. Kinetic moment variables were acquired from 35 individuals with medial knee compartment OA. A 3D motion analysis system and two force platforms were used to acquire KAM and 3D moments of both ankle joints during gait. Visual3D was used to obtain final moment data for statistical processing. Repeated-measures analysis of variance with Bonferroni adjustment was used to compare kinetic and kinematic values for each FPA walking condition. There was a significant decrease (p < 0.01) in first peak KAM when walking with an internal rotation foot position compared to normal foot position walking. Also, there was a significant decrease (p < 0.01) in second peak KAM when walking with an external rotation foot position compared to normal foot position walking. Compared to a normal foot position, peak ankle inversion moment of the external rotation foot position walking showed a significant decrease (p < 0.05). There were no interactive effects between FPA condition and limb sides for any KAM values (p > 0.05). The results showed no significant increase in the ankle joint moment value during gait for FPA modification conditions. Thus, the clinical implications of this study suggest that modification of the FPA in patients with OA to reduce KAM does not negatively impact the 3D ankle moments.

Application of Autologous Bone Graft versus Non Grafting in Medial Opening Wedge High Tibial Osteotomy Less than 14 mm: A Systematic Review and Meta-Analysis

Abstract Background Unicompartmental Knee osteoarthritis KOA due to varus malalignment is increased in young active patients which occurs predominantly in the medial compartment. Aim of the Work The objective of this study to compare MOWHTOs with autologous bone graft and without bone graft (wedge space mean less than 14 mm) in treatment of unicompartmental KOA and varus malalignment of the knee to determine which is better in decision-making according to outcomes. Patients and Methods Studies that matched the inclusion criteria were included in this meta-analysis. participants with medial compartmental knee osteoarthritis and varus malalignment were shown in the investigation. The age of the participants was unrestricted. Plate as a fixation method was the only option regardless of plate type. During 2000 and 2021, a research study of internet databases (Egyptian Universities Research, Medline, PubMed, Cochran library, medical journals) was conducted. Following that, the references from the user research were examined, and specialists were approached for assistance in locating other papers. Two independent reviewers extracted data separately and cross-checked it. Results The Knee Society Knee score (KSKS) and Knee Society Function score (KSFS) are most commonly used for the assessment of the knee joint reveled that there is no statically significant difference between bone graft vs non graft. Regarding this systematic review the radiological outcomes, the clinical bone union and the full weight bearing movement, are rendering any statistical analysis meaningless. Regarding complications presented, there was a similar tendency for complication rate when compared according to grafting or non- grafting. The use of autograft accelerates radiographic healing of the osteotomy gap after OWHTO while shorten the union time but confers no advantages in terms of functional or patient elated out comes at 3 or 12 months postoperatively. Conclusion MOWHTO can be performed without a graft with less operative time and avoiding graft harvest comorbidity with similar clinical and radiological results regarding bone union and posterior tibial slope alteration and knee scores.

Better clinical outcomes and return to sport rates with additional medial meniscus root tear repair in high tibial osteotomy for medial compartmental knee osteoarthritis.

This retrospective study aimed to investigate whether the repair of medial meniscus posterior root tears (MMPRTs) is effective for improving clinical outcomes and return to sports rates in young patients (50 years old or younger) with medial compartment knee osteoarthritis (KOA) and MMPRTs. Between 2016 and 2019, 153 patients with KOA and MMPRTs who underwent open-wedge high tibial osteotomy (OWHTO) were retrospectively included. The patients were divided into OWHTO combined with MMPRT repair (n = 73) and isolated OWHTO (n = 80) groups. Lysholm scores, Hospital for Special Surgery (HHS) scores, Tegner scores, flexion contracture, range of knee flexion, return to sports rates and postoperative complications were compared. Radiological outcomes, including hip-knee-ankle angle (HKA), medial proximal tibial angle (MPTA), joint line convergence angle (JLCA) and Kellgren-Lawrence (K-L) grade, were compared between the two groups. After a mean follow-up of 30.1 ± 3.0 months, the OWHTO + Repair group observed better clinical outcomes compared with the OWHTO group (Lysholm score: 86.7 ± 7.4 vs. 81.6 ± 6.9, p = 0.023. HHS score: 85.4 ± 8.20 vs. 80.5 ± 7.1, p = 0.039). The OWHTO + Repair group had higher Tegner scores and return to sports rates than the OWHTO group (Tegner score: 6 vs. 5, p = 0.020; return to sports rates: 38% vs. 15%, p = 0.001). No fracture or major complications occurred. Radiological outcomes showed no significant differences between the two groups (HKA: 181.1 ± 2.7 vs. 180.1 ± 1.5 n.s; MPTA: 90.1 ± 1.8 vs. 89.2 ± 1.4, n.s; JLCA:1.9 ± 0.7 vs. 2.1 ± 0.7, n.s). Additional MMPRT repair during OWHTO was associated with better clinical outcomes and higher rates of return to sports in young patients with medial compartment KOA and MMPRTs. Level III.

High tibial osteotomy versus unicompartmental knee arthroplasty in advanced medial compartmental knee arthrosis: A comparative study with propensity score matched analysis

BackgroundIsolated knee medial compartmental osteoarthritis(MOA) can be treated with High Tibial Osteotomy (HTO) or Unicompartmental Knee Arthroplasty (UKA).This study aims to describe and compare outcomes of HTO and UKA in patients with isolated severe MOA. The authors hypothesized that similar outcomes can be achieved. MethodsData was collected prospectively of HTOs and UKAs performed between January-2016 and April-2021 by a knee surgeon. Oxford Knee Score (OKS), Knee Society Knee Score (KSKS) and Function Score (KSFS) were collected pre-operatively, six-months and two-years post-surgery. OA severity was graded on pre-operative radiograph. Medial Proximal Tibia Angle (MPTA), Lateral Distal Femoral Angle (LDFA), Joint Line Convergence Angle (JLCA) and Hip-Knee-Ankle Angle (HKAA), were measured on full-length radiograph.47 HTO and 74 UKA were included. Propensity score matching was performed, accounting for preoperative scores, age, gender and body mass index (BMI), before statistical analysis. Level of significance was set at 0.05. ResultsBoth groups were similar in age(56.42 vs 58.57, p = 0.067), BMI(29.82 vs 29.09, p = 0.484), gender distribution (p = 0.663) and laterality (p = 0.836).Pre-operatively, both groups were similar in clinical scores and lower limb alignment. On follow-up, both groups achieved similar improvements in clinical scores. However, the HTO group reported poorer extension at 6-months (7.91° vs 4.80°, p = 0.013) and 2-years (5.57° vs 3.24°, p = 0.018).Three cases of hinge fracture and six cases of implant removal occurred in the HTO group. One case of tibial fracture occurred in the UKA group. ConclusionsIn severe MOA, similar outcomes were achieved with HTO and UKA at two years.

Cartilage regeneration and long term survival in medial OA knee patients treated with HTO and OATS

BackgroundOsteoarthritis (OA) of the knee, in most instances primarily, affects medial compartment of knee. Combining Osteochondral Autologous Transfer System (OATS) with Medial Open-Wedge High Tibial Osteotomy (MOWHTO) may represent an integrated approach to sustaining long-term knee functionality in OA patients. Materials and methodsFrom 2009 to 2016, combined OATS and MOWHTO was performed in 66 knees of 63 patients with medial compartment knee OA. Cartilage regeneration was assessed by 2nd look arthroscopy and Knee function was assessed by knee society scoring (KSS) pre-operatively and post-operatively. The survival rate of MOWHTO plus OATS was assessed. Failure is characterized by the need to convert into total knee replacement. ResultsThe KSS knee score (from 48.3 to 90.4) and function score (from 42.6 to 88.7) showed a statistically significant improvement (p-value of <0.0001) at a mean follow-up period of 9.49 years. Second look arthroscopy done at the time of implant removal showed 100 % cartilage regeneration with even hyaline cartilage regeneration in 49 out of 57 knees assessed and partial regeneration in 8 knees. The Kaplan Meier survivorship analysis was 96.7 % at the mean 9.49 years after surgery. Only 2 patients needed TKA conversion in follow-up. ConclusionCombining OATs and valgus MOWHTO provides good option to successfully manage patients of OA and varus malalignment. This resulted in significant improvement in knee function, lowering pain intensity, good cartilage regeneration, and a high survivorship rate for 10 years postoperatively.

In vivo human knee varus-valgus loading apparatus for analysis of MRI-based intratissue strain and relaxometry

The diagnosis of early-stage osteoarthritis remains as an unmet challenge in medicine and a roadblock to evaluating the efficacy of disease-modifying treatments. Recent studies demonstrate that unique patterns of intratissue cartilage deformation under cyclic loading can serve as potential biomarkers to detect early disease pathogenesis. However, a workflow to obtain deformation, strain maps, and quantitative MRI metrics due to the loading of articular cartilage in vivo has not been fully developed. In this study, we characterize and demonstrate an apparatus that is capable of applying a varus-valgus load to the human knee in vivo within an MRI environment to enable the measurement of cartilage structure and mechanical function. The apparatus was first tested in a lab environment, then the functionality and utility of the apparatus were examined during varus loading in a clinical 3T MRI system for human imaging. We found that the device enables quantitative MRI metrics for biomechanics and relaxometry data acquisition during joint loading leading to compression of the medial knee compartment. Integration with spiral DENSE MRI during cyclic loading provided time-dependent displacement and strain maps within the tibiofemoral cartilage. The results from these procedures demonstrate that the performance of this loading apparatus meets the design criteria and enables a simple and practical workflow for future studies of clinical cohorts, and the identification and validation of imaging-based biomechanical biomarkers.

Allotendoplasty in Treatment of Habitual Patella Dislocation in Adults

Background. Habitual dislocation of patella is a congenital disease that manifests in early childhood or adolescent age and requires surgical treatment. In case this condition has not been rectified timely, the congenial patellar luxation develops the properties of a habitual dislocation accompanied by pain syndrome and osteoarthrosis development in the patellofemoral and knee joints. In most cases reconstructive surgery is used for this disease treatment; it is aimed at the strengthening of the knee joint interval compartment, with the formation of a fibrous graſt or a vertical strip of it, which are moved to the knee joint outside compartment and fixed to adjacent tissues with sutures. However, such surgery is possible only in case of preserved anatomic structures of the knee medial compartment. In adult patients, aſter multiple patellar dislocations, the interval joint capsule and medial aponeurosis lose their normal structure, become weakened, strained, and loose. That is why the patient’s own tissues from that area cannot be used for reconstructive surgery.The purpose of the study is to develop the new low-traumatic method of treatment for habitual dislocation of kneecap in adult patients to ensure its reliable stabilization as related to the joint surface on distal femoral epimetaphys, and to prevent patella dislocation relapse.Material and methods. Surgery technique consists of the lateral release of knee joint, mobilization of patellar ligament and its excision together with the fragment of tibial tuberosity osseous. On 1.5–2.0 cm medially from the area of own patellar ligament harvesting in tibia epimetaphys, the new bed with the similar form and shape is formed, and the excised tibial tuberosity fragment with patellar ligament is introduced there and fixed with a Cancellous screw.The area of own patellar ligament harvestingis filled up with autogenous osseous tissue taken from the medial part of tibia epimetaphys when forming the new bed for the excised tibial tuberosity fragment. Transversal tunnelis formedin the quadriceps tendon above the patella; allotendonis pulledvia this tunnel. The allotendon ends are sutured together, thus forming the duplication, analogous to the ligament, and fixit, stretched to “pes anserinus” of the shin onits anterior-interior surface.Conclusion. The new technology of allotendoplasty for the treatment of habitual kneecap dislocation in adult patients facilitates the surgical technique, additionally strengthens medial compartment tissues of the knee, reliably stabilizes the patella as related to its joint surface on distal femoral epimetaphys, eliminates patella dislocation relapse, normalizes the knee and patellofemoral joints functioning by preventing osteoarthrosis progression in them.

The effect of incline walking on lower extremity and trunk mechanics in older adults

Older adults are at an increased risk of developing knee osteoarthritis. High internal knee abduction moment during daily activities may elevate the risk of knee osteoarthritis. Incline walking exercise has been found to decrease knee abduction moment in healthy young adults. However, it is unknown if this occurs in healthy older adults. The purpose of this study was to quantify the internal knee abduction moment at different treadmill grades to determine if incline walking could reduce the knee abduction moment in healthy older adults. Twelve healthy older adult males walked on a treadmill at five incline grades (0%, 5%, 10%, 15%, and 20%) at 1.34 ​m⋅s-1. The primary outcome variable was the internal knee abduction moment. A one-way repeated measures multivariate analysis of variance was performed to determine differences in the dependent variables among incline gradients. Peak knee abduction moment significantly decreased from level walking at all gradients in 10% increments (0%–10%, p ​< ​0.001; 5%–15%, p ​< ​0.002; and 10%–20%, p ​= ​0.04). A reduction in knee abduction moment during incline walking could result in decreased knee joint loading on the medial knee compartment. For older adults, who are looking to exercise to improve their health, incline walking may be beneficial to promote lower body strength and cardiovascular ability without inflicting further harm to the aging knee joints. However, because the frontal plane knee joint was of primary interest in this study, further research is needed to determine the effects of incline walking on other joints and in other planes of motion.

Influence of leg axis alignment on MRI T2* mapping of the knee in young professional soccer players

BackgroundInvestigation of the association between leg axis alignment and biochemical MRI in young professional soccer players in order to identify a potential influence of the leg axis on cartilage regions at risk.MethodsSixteen professional soccer players (21 ± 3 years) underwent static and dynamic leg axis analysis via radiation free DIERS formetric 4 D as well as 3-T MRI examination of both knees. Quantitative T2* mapping of the knee cartilage was performed and T2* values were evaluated as 144 regions of interest. Subgroup analysis was performed in players with severe varus alignment (> 6°).ResultsAnalysis of the leg axis geometry revealed a mean static alignment of 6.6° ± 2.5 varus and a mean dynamic alignment of 5.1° ± 2.6 varus. Quantitative T2* mapping showed significantly increased T2* values in the superficial cartilage layer compared to the deeper region (p < 0.001) as well as a significant increase in relaxation times in the femoral cartilage from anterior to intermediate to posterior (p < 0.001). Combination of both methods revealed a significant correlation for the degree of varus alignment and the femoral, posterior, deep region of the medial knee compartment (r = 0.4; p = 0.03). If severe varus alignment was present this region showed a significant increase in relaxation time compared to players with a less pronounced leg axis deviation (p = 0.003).ConclusionThis study demonstrates that varus alignment in young soccer players is associated with elevated T2* relaxation times in the deep cartilage layer of the medial, posterior, femoral compartment and might therefore be a contributing factor in the early pathogenesis of manifest cartilage lesions. Therefore, these findings should be considered in the development of preventive training programs.

Mid-term effects of unicompartmental knee arthroplasty combined with anterior cruciate ligament reconstruction for the medial compartment osteoarthritis with anterior cruciate ligament deficiency by proportioning with the pure medial compartment osteoarthritis

Objective: To evaluate the mid-term efficacy of one-stage unicompartmental knee arthroplasty (UKA) combined with anterior cruciate ligament (ACL) reconstruction in the treatment of medial compartment osteoarthritis (OA) with ACL deficiency. Methods: Retrospective cohort study. The clinical data of 13 patients (14 knees) who underwent UKA with ACL reconstruction for knee medial compartment OA combined with ACL deficiency in Wangjing Hospital of China Academy of Chinese Medical Sciences from January 2012 to January 2020 were retrospective analyzed. A 1∶1 proportioning study was conducted with 13 patients (14 knees) who underwent UKA due to medial compartment OA with intact ACL during the same period. The matching conditions were the same gender, age, surgical side, anesthesia method, comorbidities, and imaging lesions. There were 26 patients (28 knees) in the two groups, including 6 males (6 knees) and 20 females (22 knees), aged (58.9±4.2) years. The range of motion (ROM) and Oxford Knee Score (OKS) were used to evaluate the knee joint function at the last follow-up. The anteroposterior, lateral and axial X-ray films of the knee joint and the weight-bearing full-length X-ray films of the lower limbs were taken during follow-up. The hip knee ankle (HKA) angle, the posterior slope angle (PSA) of tibial prosthesis, and the anterior tibial translation (ATT) were recorded and compared between the two groups. The progression of lateral compartment OA, prosthesis loosening, and dislocation were evaluated. The mid-term follow-up clinical efficacy of the two surgical methods was compared, and the etiology of the patients was analyzed to verify the clinical efficacy and patient selection of one-stage UKA combined with ACL reconstruction. Results: The follow-up time of the two groups was (7.14±2.45) years. At the last follow-up, there was no significant difference in joint ROM between the combined group and the UKA group (120.90°±2.95° vs 122.29°±3.22°, P=0.260). There was no significant difference in OKS score between the two groups [(42.50±1.99) vs (43.21±2.26), P=0.380]. There was no significant difference in HKA angle and ATT distance between the two groups before operation (both P>0.05). At the last follow-up, the results were better than those before operation, and the differences were statistically significant (both P<0.05). At the last follow-up, there was no significant difference in HKA Angle between the combined group and the simple group (177.79°±1.25 ° vs 177.86°±1.29°, P=0.880). Tibial prosthesis PSA and ATT distance were not significantly different between the two groups [(4.57°±0.94° vs 4.50°±1.34°and (0.21±0.89) mm vs (0.14±1.35) mm, both P>0.05)]. There was no prosthesis loosening and obvious progression of lateral compartment OA in both groups at the last follow-up. Conclusion: For young patients with medial compartment OA secondary to ACL deficiency, UKA combined with ACL reconstruction is recommended, it can obtain good mid-term results.

Load-induced blood marker kinetics in patients with medial knee compartment osteoarthritis are associated with accumulated load and patient reported outcome measures.

This study aimed to quantify the mechanoresponse of 10 blood marker candidates for joint metabolism to a walking stress test in patients with knee osteoarthritis and to determine the association among marker kinetics and with accumulated load and patient reported outcomes. 24 patients with knee osteoarthritis completed questionnaires, and a 30-minute walking stress test with six blood serum samples and gait analysis. Concentrations of cartilage oligomeric matrix protein (COMP), matrix metalloproteinases (MMP)-1, -3, and -9, epitope resulting from cleavage of type II collagen by collagenases (C2C), type II procollagen (CPII), interleukin (IL)-6, proteoglycan (PRG)-4, A disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)-4, and resistin were determined by enzyme-linked immunosorbent assays, Joint load (moments and compartmental forces) was estimated using musculoskeletal modeling using gait analysis data. COMP and MMP-3 showed an immediate increase after the walking stress followed by a decrease. MMP-9 and resistin showed a delayed decrease below pre-stress levels. ∆COMP correlated with ∆MMP-3 for most time points. ∆MMP-9 correlated with ∆resistin for most time points. The load-induced increase in blood marker levels correlated among blood markers and time points. C2C and resistin correlated positively and C2C/CPII and MMP2 correlated negatively with load during gait. Immediate relative ∆CPII and ∆MMP1 and delayed relative ∆COMP, ∆IL6, ∆C2C, ∆CPII, ∆MMP1 and ∆MMP3 correlated with the load accumulated during the walking stress. Baseline C2C levels correlated with Knee Osteoarthritis Outcome Score (KOOS) subscales and load-induced changes in MMP-3 with KOOS and Short Form 36 quality of life subscores (P<0.05). The distinct and differentiated physiological response to the walking stress depends on accumulated load and appears relevant for patient reported osteoarthritis outcome and quality of life and warrants further investigation in the context of disease progression.ClinicalTrials.gov registration: NCT02622204.

Advancements in health informatics: finite element insights into medial open-wedge high tibial osteotomy and lateral meniscal tears.

Knee medial compartment osteoarthritis is effectively treated by a medial open-wedge high tibial osteotomy (MOWHTO). The feasibility and safety of MOWHTO for mild lateral meniscal tears are unknown. This study examined the feasibility and safety of knee joint weight-bearing line ratio (WBLr) adjustment during MOWHTO with lateral meniscal injuries. We used a healthy adult male's lower extremities computed tomography scans and knee joint magnetic resonance imaging images to create a normal fine element (FE) model. Based on this model, we generated nine FE models for the MOWHTO operation (WBLr: 40-80%) and 15 models for various lateral meniscal injuries. A compressive load of 650N was applied to all cases to calculate the von Mises stress (VMS), and the intact lateral meniscus' maximal VMS at 77.5% WBLr was accepted as the corrective upper limit stress. Our experimental results show that mild lateral meniscal tears can withstand MOWHTO, while severe tears cannot. Our findings expand the use of MOWHTO and provide a theoretical direction for practical decisions in patients with lateral meniscal injuries.

Effect of adding hip exercises to general rehabilitation treatment of knee osteoarthritis on patients’ physical functions: a randomized clinical trial

BackgroundHip adductor and abductor strength were both reduced in KOA patients. But to date, most of the researches have only focused on quadriceps combined with hip abductor strengthening versus quadriceps strengthening.ObjectiveThe aim of the study is to evaluate the effect of adding hip abductor and adductor strengthening to quadriceps strengthening on lower limb strength, knee pain and physical function in patients with medial compartmental knee osteoarthritis.MethodsIn this study, 42 participants, were randomly divided into two groups: the general treatment group (GT group) and the added-hip-exercise group (AH group). All participants were given a general rehabilitation treatment. The AH group performed hip abductor and adductor strengthening in addition to the general rehabilitation treatment. Knee and hip muscle strength, Five Times Sit-to-Stand Test (FTSST), the Timed Up and Go Test (TUGT), Numerical Rating Scale (NRS), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were assessed at baseline and 6 weeks. A two-sided 2-sample unpaired t test was performed to compare the difference in mean change scores between AH and GT groups.ResultsFinally, 36 participants completed the study: both groups consist of 18 participants. In the per-protocol analysis, the AH group had a greater improvement in knee extension strength (mean changes, 7.84 versus 36.48; P < 0.001) and hip abduction strength (mean changes, 5.05 versus 26.62; P = 0.001) than the control group. Similarly, the AH group had a greater improvement in the FTSST time (mean changes, 0.40 s versus 3.57 s; P < 0.001) and the TUFT time (mean changes, 0.18 s versus 1.67 s; P = 0.002) than the GH group. No statistical difference was found in the change of WOMAC pain scores and NRS between the 2 groups.ConclusionsOlder adults with knee OA in the AH group had superior muscle strength, symptoms and daily activity performance at the 6th week than those in the GT group. And adding hip exercises could expedite improvement of pain at the 2th week, but not at the 6th week.Trial registrationClinical trial registration numbers and date of registration: ChiCTR-IOR-16009124, Registered 30 August 2016.

THE MECHANICAL REGULATION OF SEMA3A IN PATIENT SYNOVIAL FLUID WITH CHRONIC KNEE VARUS MALALIGNMENT

AbstractOBJECTIVEKnee varus malalignment increases medial knee compartment loading and is associated with knee osteoarthritis (OA) progression and severity1. Altered biomechanical loading and dysregulation of joint tissue biology drive OA progression, but mechanistic links between these factors are lacking. Subchondral bone structural changes are biomechanically driven, involve bone resorption, immune cell influx, angiogenesis, and sensory nerve invasion, and contribute to joint destruction and pain2. We have investigated mechanisms underlying this involving RANKL and alkaline phosphatase (ALP), which reflect bone resorption and mineralisation respectively3 and the axonal guidance factor Sema3A. Sema3A is osteotropic, expressed by mechanically sensitive osteocytes, and an inhibitor of sensory nerve, blood vessel and immune cell invasion4. Sema3A is also differentially expressed in human OA bone5.HYPOTHESIS: Medial knee compartment overloading in varus knee malalignment patients causes dysregulation of bone derived Sema3A signalling directly linking joint biomechanics to pathology and pain.METHODSSynovial fluid obtained from 30 subjects with medial knee OA (KL grade II-IV) undergoing high tibial osteotomy surgery (HTO) was analysed by mesoscale discovery and ELISA analysis for inflammatory, neural and bone turnover markers. 11 of these patients had been previously analysed in a published patient-specific musculoskeletal model6 of gait estimating joint contact location, pressure, forces, and medial-lateral condyle load distribution in a published data set included in analyses. Data analysis was performed using Pearson's correlation matrices and principal component analyses. Principal Components (PCs) with eigenvalues greater than 1 were analysed.RESULTSPC1 (32.94% of variation) and PC2 (25.79% of variation) from PCA analysis and correlation matrices separated patients according to correlated clusters of established inflammatory markers of OA pain and progression (IL6/IL8, r=0.754, p&lt;0.001) and anti-inflammatory mediators (IL4/IL10, r=0.469, p=0.005). Bone turnover marker ALP was positively associated with KL grade (r=0.815, p=0.002) and negatively associated with IL10 (r=−0.402, p=0.018) and first peak knee loading pressures (r=−0.688, p=0.019). RANKL was positively associated with IL4 (r=0.489, p=0.003). Synovial fluid Sema3A concentrations showed separate clustering from all OA progression markers and was inversely correlated with TNF-α (r=−0.423, p=0.022) in HTO patients. Sema3A was significantly inversely correlated with total predicted force in the medial joint compartment (r=−0.621, p=0.041), mean (r=−0.63, p=0.038) and maximum (r=−0.613, p=0.045) calculated medial compartment joint pressures during the first phase and mean (r=−0.618, p=0.043) and maximum (r=−0.641, p=0.034) medial compartment joint pressures during midstance outputs of patient-specific musculoskeletal model.CONCLUSIONSThis study shows joint inflammatory status and mechanical overloading influence subchondral bone-remodelling. Synovial Sema3A concentrations are inversely correlated to patient-specific musculoskeletal model estimations of pathological medial overloading. This study reveals Sema3A as a biological mediator with capacity to induce OA pain and disease progression that is directly regulated by gait mechanical loading.Declaration of Interest(b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Medial opening-wedge high tibial osteotomy with microfracture in treatment of varus medial compartmental knee osteoarthritis: clinical outcomes and second-look arthroscopic results.

Objective: This study aimed to investigate the clinical outcomes of medial opening high tibial osteotomy (MOWHTO) combined with arthroscopic microfracture in the treatment of varus medial compartmental knee osteoarthritis and to assess cartilage regeneration using second-look arthroscopy. Methods: This study involved 86 patients (86 knees) who underwent MOWHTO and microfracture from August 2016 to August 2020, including 15 men and 71 women with an average age of 55.3 ± 7.6years (range, 42-71years). The patients underwent a second-look arthroscopy to evaluate the status of cartilage regeneration at the time of plate removal, an average of 2years after the initial osteotomy. Clinical and radiological examinations were performed preoperatively and at the final follow-up visit. The radiologic evaluation included the weight-bearing line ratio (WBL ratio), mechanical femorotibial angle (FTA), medial proximal tibial angle (MPTA), posterior tibial slope angle (PTS) and Kellgren-Lawrence (KL) grade. Clinical outcomes were assessed using the Knee Society score (KSS) and International Knee Documentation Committee (IKDC) scores. Arthroscopic findings were assessed by macroscopic evaluation of cartilage repair according to the International Cartilage Repair Society (ICRS) grading system. Results: The mean KSS and IKDC scores significantly improved at the final follow-up compared to the scores obtained preoperatively (p < 0.05). At the time of plate removal, a second-look arthroscopic examination showed that the ICRS grade of the medial femoral condyle was as follows: grade I -11 cases, grade II -56, grade III-12, and grade IV-7, and cartilage regeneration was seen in 85% of knees (73/86). The ICRS grade of medial tibial plateau was grade I-12 cases, grade II-44, grade III-22, and grade IV-8, and cartilage regeneration was seen in 63% of knees (54/86). Significant differences were observed between cartilage regeneration and clinical outcomes (p < 0.05). Clinical results were better in the good cartilage regeneration group (grades I and II) than were in the poor cartilage regeneration group (grades III and IV). Conclusion: MOWHTO combined with arthroscopic microfracture can effectively improve clinical outcomes in the treatment of varus medial compartmental knee osteoarthritis. Cartilage regeneration can be promoted by correcting varus deformities, which affect clinical outcomes.

Derotational Hybrid Closed-Wedge High Tibial Osteotomy for Knee Osteoarthritis With Patellar Subluxation Caused by Tibial Torsional Deformity

Patellar subluxation and recurrent dislocation are commonly treated with medial patellofemoral ligament reconstruction, and patients with predisposing factors for these problems often require additional bony realignment procedures. However, these procedures mainly address problems in the axial plane, and patients with medial-compartmental knee osteoarthritis may require further realignment in the coronal plane. In this Technical Note article, we introduce our technique for derotational hybrid closed-wedge high tibial osteotomy. Using this technique, simultaneous 3-dimensional realignment in the axial, coronal, and sagittal planes can be achieved in patients with medial compartmental knee osteoarthritis and patellar subluxation caused by a tibial torsional deformity. The indications for the technique and the preoperative planning assessments involving a static torsional deformity analysis on computed tomography images and a dynamic gait analysis by our walking-on-paper method are presented. This is followed by a detailed description of the surgical procedure, together with consideration of the pearls and pitfalls of the procedure. A video of the surgery performed in a representative case with medial knee osteoarthritis and patellar subluxation in the right knee owing to an outward tibial torsion deformity is also provided.

FUNCTIONAL OUTCOME OF PATIENTS WITH MODERATE-TO-SEVERE MEDIAL COMPARTMENT OSTEOARTHRITIS KNEE TREATED BY HIGH TIBIAL OSTEOTOMY AT A TERTIARY CARE CENTER

Objectives: (1) The aims and objectives of the study are to assess functional outcomes in knee osteoarthritis (OA) cases treated by high tibial osteotomy (HTO) and (2) to study the complications in patients undergoing HTO. Methods: This was a prospective study conducted in the Department of Orthopedics of a tertiary care medical college. 50 patients with moderate-to-severe OA of medial compartment of knee were included in this study. All patients underwent HTO. Post-operatively, patients were followed up for 6 months. During follow-up visits, reduction in pain intensity and functional outcome were assessed by visual analog scale (VAS) score and Japanese Orthopedic Association (JOA) Score. Patients were also assessed for complications if any. For statistical purposes, p&lt;0.05 was taken as statistically significant. Results: Out of 50 studied cases, there was a female preponderance with an M: F ratio of 1:1.38. The mean age of affected cases was found to be 62.32±8.94 years. 11 (22.00%) patients were obese (body mass index [BMI] ≥30) and 32 (64.00%) patients were overweight (BMI ≥25 but &lt;30). 7 (14.00%) patients had BMI &lt;25. 38 (76%) patients had severe OA whereas in remaining 12 (24%) patients, there was moderate OA. There was a significant reduction in pain, as assessed by VAS score, at the time of final follow-up as compared to VAS score at the time of presentation (p&lt;0.0001). Similarly, there was a significant functional improvement, as assessed by JOA score, at the time of final follow-up as compared to JOA score at the time of presentation (p&lt;0.0001). 7 (14%) patients developed minor complications. All these complications were managed conservatively. Conclusion: Patients with moderate to severe OA of medial compartment of knee treated by HTO show excellent outcomes in terms of pain relief and functional outcomes.