Sonographically Guided Knee Meniscus Injections: Feasibility, Techniques, and Validation

BackgroundThere is a growing interest in the use of biologic agents such as platelet‐rich plasma and mesenchymal stem/stromal cells to treat musculoskeletal injuries, including meniscal tears. Although previous research has documented the role of diagnostic ultrasound to evaluate meniscal tears, sonographically guided (SG) techniques to specifically deliver therapeutic agents into the meniscus have not been described.ObjectiveTo describe and validate SG injection techniques for the body and posterior horn of the medial and lateral meniscus.DesignProspective, cadaveric laboratory investigation.SettingAcademic institution procedural skills laboratory.SubjectsFive unenbalmed cadaveric knee‐ankle‐foot specimens from 5 donors (3 female and 2 male) ages 33‐92 years (mean age 74 years) with body mass indices of 21.1‐32.4 kg/m2 (mean 24.1 kg/m2).MethodsA single, experienced operator completed SG injections into the bodies and posterior horns of the medial and lateral menisci of 5 unenbalmed cadaveric knees using colored latex and a 22‐gauge, 38‐mm needle. After injection, coinvestigators dissected each specimen to assess latex distribution within the menisci and identify injury to intra‐articular and periarticular structures.Main Outcome MeasuresLatex location within the target region of meniscus (accurate/inaccurate), and iatrogenic injury to “at risk” intra‐ and periarticular structures (present/absent).ResultsSeventeen of 20 injections were accurate. Two of 3 inaccurate injections infiltrated the posterior horn of the medial meniscus instead of the targeted meniscal body. One inaccurate lateral meniscus injection did not contain latex despite sonographically accurate needle placement. No specimen exhibited injury to regional neurovascular structures or intra‐articular hyaline cartilage.ConclusionsSG meniscus injections are feasible and can accurately and safely deliver injectates such as regenerative agents into bodies and posterior horns of the medial and lateral menisci. The role of SG intrameniscal injections in the treatment of patients with degenerative and traumatic meniscal disorders warrants further exploration.Level of EvidenceNot applicable.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/147070/1/pmr2998.pd

Simulation of Subject-Specific Progression of Knee Osteoarthritis and Comparison to Experimental Follow-up Data : Data from the Osteoarthritis Initiative

Economic costs of osteoarthritis (OA) are considerable. However, there are no clinical tools to predict the progression of OA or guide patients to a correct treatment for preventing OA. We tested the ability of our cartilage degeneration algorithm to predict the subject-specific development of OA and separate groups with different OA levels. The algorithm was able to predict OA progression similarly with the experimental follow-up data and separate subjects with radiographical OA (Kellgren-Lawrence (KL) grade 2 and 3) from healthy subjects (KL0). Maximum degeneration and degenerated volumes within cartilage were significantly higher (p <0.05) in OA compared to healthy subjects, KL3 group showing the highest degeneration values. Presented algorithm shows a great potential to predict subjectspecific progression of knee OA and has a clinical potential by simulating the effect of interventions on the progression of OA, thus helping decision making in an attempt to delay or prevent further OA symptoms.Peer reviewe

Артроскопическая менискэктомия у больных гонартрозом: разрыв между доказательной медициной и мнением практикующего специалиста

Background. For many decades arthroscopy considered to be the least invasive procedure among all surgical interventions for treatment of knee osteoarthritis (OA). In the beginning of XXI century several randomized clinical studies (RCS) demonstrated inefficiency of lavage and debridement for knee OA. The evidence regarding partial meniscectomy for this category of patients remained uncertain. Therefore the published clinical guidelines are either controversial or inconclusive. The aim of this study was to critically review the current RCS and meta-analyses of RCS as well as actual clinical guidelines of international orthopedic societies and compare them to expert opinions. Methods. We searched PubMed and eLIBRARY databases for high evidence research and analyzed the current clinical guidelines dedicated to partial meniscectomy for knee OA. Sixty orthopedic surgeons specialized in this field interviewed anonymously to clarify the decision making process in real clinical practice. Results. More than patients with knee 2/3 OA of with degenerative meniscal tear benefit from non-surgical treatment therefore indication for arthroscopic partial meniscectomy is limited. The majority of current clinical guidelines consider surgery as an second option if conservative treatment failed and only for non-advanced knee OA. On the contrary experts interview demonstrated the lack of standardized approach as well as a lot of controversies in clinical decision making. Conclusion. The future research dedicated to partial meniscectomy in knee OA should be appropriately designed to clearly differentiate the sub-population of patient who may benefit from arthroscopy in the long-term without carrying the risk of rapid disease progression with premature conversion to arthroplasty.Актуальность. Артроскопия многие десятилетия считалась наименее инвазивным из всех существующих хирургических методов лечения больных гонартрозом, однако проведенные в начале XXI в. рандомизированные клинические исследования (РКИ) продемонстрировали бесполезность изолированного лаважа и дебридмента у данной категории пациентов. В отношении частичной менискэктомии при гонартрозе существующая доказательная база остается весьма разнородной, что отражается в противоречивости или неопределенности клинических рекомендаций большинства профессиональных сообществ, посвященных данной проблеме. Целью исследования стало проведение критического анализа публикаций высокого уровня доказательности и актуальных клинических рекомендаций, посвященных частичной менискэктомии у пациентов с гонартрозом для сравнения с мнением практикующих специалистов по данной проблеме. Материал и методы. Нами были проанализированы РКИ и метаанализы РКИ в базах данных eLIBRARY и PubMed, а также действующие клинические рекомендации ведущих профессиональных сообществ, посвященные частичной менискэктомии у больных гонартрозом. Для детализации понимания процесса принятия решений в реальной клинической практике и оценки роли мнения эксперта в иерархии доказательной медицины был произведен анонимный опрос 60 практикующих травматологов-ортопедов, специализирующихся на лечении пациентов с данной патологией. Результаты. Актуальные научные исследования высокого уровня доказательности демонстрируют, что более 2/3 больных гонартрозом с повреждением мениска достигают купирования симптомов в результате комплексного консервативного лечения, поэтому показания к артроскопии при дегенеративных заболеваниях коленного сустава носят весьма ограниченный характер. Большинство действующих клинических рекомендаций склоняются к артроскопической менискэктомии в качестве метода выбора лечения второго уровня после неэффективности неоперативного подхода и только у пациентов с минимальными клинико-рентгенологическими проявлениями гонартроза. В то же время проведенный нами опрос свидетельствует об отсутствии единого мнения о данной проблеме среди практикующих отечественных специалистов. Заключение. Основываясь на полученных данных, следует констатировать необходимость проведения качественных многоцентровых исследований, которые позволят выявить конкретную группу пациентов с определенным фенотипом гонартроза, у которых артроскопическая менискэктомия может быть эффективной в долгосрочной перспективе, не ускоряя прогрессирование заболевания с последующей необходимостью эндопротезирования

Finite element analysis of the meniscectomised tibio-femoral joint: implementation of advanced articular cartilage models

The article presents advanced computer simulations aimed at the accurate modelling of human tibio-femoral joints (TFJs) in terms of anatomy, physiological loading and constitutive behaviour of the tissues. The main objective of this research is to demonstrate the implications that the implementation of different articular cartilage models have on the prediction of the joint response. Several biphasic material constitutive laws are tested using a finite element package and compared to the monophasic linear elastic description, often still used to predict the instantaneous response of the cartilage in 3D knee models. Thus, the importance of adequately capturing the contribution of the interstitial fluid support is proved using a simplified 3D model; subsequently, a biphasic poroviscoelastic non-linear constitutive law is implemented to study the response of a patient-specific TFJ subjected to simplified walking cycles. The time evolution of stresses, pore pressure, contact areas and joint displacements is captured and compared with existing meniscectomised knee models. Contact pressures and areas obtained using the developed numerical simulations are in agreement with the existing experimental evidence for meniscectomised human knee joints. The results are then used to predict the most likely site for the origin of mechanical damage, i.e. the medial cartilage surface for the specific case analysed in the present contribution. Finally, future research directions are suggested. © 2013 © 2013 Taylor & Francis

Finite element analysis of the meniscectomised tibio-femoral joint: implementation of advanced articular cartilage models

The article presents advanced computer simulations aimed at the accurate modelling of human tibio-femoral joints (TFJs) in terms of anatomy, physiological loading and constitutive behaviour of the tissues. The main objective of this research is to demonstrate the implications that the implementation of different articular cartilage models have on the prediction of the joint response. Several biphasic material constitutive laws are tested using a finite element package and compared to the monophasic linear elastic description, often still used to predict the instantaneous response of the cartilage in 3D knee models. Thus, the importance of adequately capturing the contribution of the interstitial fluid support is proved using a simplified 3D model; subsequently, a biphasic poroviscoelastic non-linear constitutive law is implemented to study the response of a patient-specific TFJ subjected to simplified walking cycles. The time evolution of stresses, pore pressure, contact areas and joint displacements is captured and compared with existing meniscectomised knee models. Contact pressures and areas obtained using the developed numerical simulations are in agreement with the existing experimental evidence for meniscectomised human knee joints. The results are then used to predict the most likely site for the origin of mechanical damage, i.e. the medial cartilage surface for the specific case analysed in the present contribution. Finally, future research directions are suggested

Subject-Specific Finite Element Modeling of the Tibiofemoral Joint in Vivo: Development, Verification and Application

A new methodology for subject-specific finite element (FE) modeling of the tibiofemoral (TF) joint based on in vivo computed tomography (CT), magnetic resonance imaging (MRI), and dynamic stereo-radiography (DSX) data is presented. Two techniques to incorporate in vivo skeletal kinematics as FE boundary conditions were implemented and compared: one used MRI-measured tibiofemoral kinematics in a non-weight-bearing supine position and allowed five degrees of freedom at the joint in response to an axially applied force; the other used DSX-measured tibiofemoral kinematics in a weight-bearing standing position and permitted only axial translation in response to the same force. The model-predicted cartilage-cartilage contact areas were examined against ‘benchmarks’ from a novel in situ contact area analysis (ISCAA) in which the intersection volume between non-deformed femoral and tibial cartilage was characterized to determine the contact. The results showed that the DSX-based model predicted contact areas in close alignment with the benchmarks, and outperformed the MRI-based model. The importance of accurate, task-specific skeletal kinematics in subject-specific FE modeling and the necessity of subject-specific verification are discussed. A study of the effects of partial meniscectomy on the intra-articular contact mechanics was then conducted as an illustration of application of the verified models. A musculoskeletal dynamic model was used to generate the knee joint forces as boundary conditions for the above developed FE models. Thus, a sequence of quasi-static position-dependent FE models was developed for a series of time points throughout a decline walking task. These time points include heel-strike and in increments of 0.05 seconds up to 0.30 seconds, and additionally, the time points of the two peak compressive joint force values for each knee. Several factors were observed to measure the effects on intra-articular contact mechanics. The greatest maximum compressive stress was recorded in the partially meniscectomized compartment or in the opposite compartment of the contralateral knee throughout all time points. The significance of the application of the FE models for evaluation of the biomechanical effects of meniscectomy is demonstrated, and the importance of simultaneously observing joint kinematics and intra-articular contact mechanics at more than one time point during a dynamic task is discussed

The Effect of High Tibial Osteotomy Correction Angle on Cartilage and Meniscus Loading Using Finite Element Analysis

Medial opening wedge high tibial osteotomy (MOWHTO) is a popular clinical method for curing the osteoarthritis (OA) caused by varus deformity. However, the ideal alignment to maximize osteotomy successful rate and post-operative knee function remains controversial to date. Moreover, the between-patient variability of knee joint biomechanics, particularly during functional tasks, signifies critical importance of conducting patient-specific planning. For this reason, this study introduces a subject-specific modeling procedure to determine the biomechanical effects of simulated different alignments of MOWHTO on tibiofemoral cartilage stress distribution. A 3D finite element (FE) knee model was developed from MRI images of a healthy living subject and used to simulate different alignments following MOWHTO (i.e. 0.2°, 2.7°, 3.9° and 6.6° valgus). Loading and boundary conditions were assigned based on the subject-specific kinematic and kinetic data recorded during gait tests. The compressive and shear stress distributions in the femoral cartilage and tibia cartilage were quantified. It was found that when the loading axis shifted laterally, the peak stresses in the medial compartment decreased, but increased in the lateral compartment. The findings suggest that equal loading between two compartments can be successfully achieved by performing MOWHTO with a HKA angle around 3.9 to 6.6° valgus. More importantly, this patient-specific non-invasive analysis of stress distribution that provided a quantitative insight to evaluate the mechanical responses of the soft tissue within knee joint as a result of adjusting the loading axis, may be used as a preoperative assessment tool to predict the consequential mechanical loading information for surgeon to decide the patient specific optimal angle

Predicting Meniscus Mechanical Properties using Quantitative Magnetization Transfer Magnetic Resonance Imaging

Osteoarthritis (OA) is a degenerative joint disease that affects the entire knee joint, afflicting approximately 13% of the Canadian population. The meniscus plays a key role in load bearing and stability of the knee joint, and its functionality is compromised throughout OA progression. Currently there does not exist a way to study the relationship between meniscal tissue degeneration and mechanical properties in vivo, but Quantitative Magnetization Transfer Magnetic Resonance Imaging (qMT MRI) is a quantitative MRI technique which may be a good candidate for this application. This is because qMT models soft tissues in a comparable way to how tissues are modeled mechanically, and qMT is dependent on water/macromolecule interactions similar to meniscal tissue functionality. The aim of this project is to assess whether qMT metrics – bound-pool fraction (f), magnetization exchange rate (k), and relaxation times of the free and bound pools (T1f, T2f, and T2b) – accurately predict experimentally-derived mechanical properties – aggregate modulus (Ha) and permeability (kp) – of excised meniscal samples. Six human cadaver knee specimens were imaged using qMT MRI techniques in order to obtain imaging metrics of the menisci. Subsequent to imaging, 59 core meniscal samples were tested using a stress relaxation approach in a confined compression testing configuration in order to obtain Ha and kp of the samples as measures of mechanical properties. A Spearman’s rho correlation was then performed on the mechanical properties and the imaging metrics of the core samples of the menisci to determine how well the imaging metrics predict the mechanical properties. One correlation, albeit weak, was found between mechanical properties and qMT metrics (Ha and T2b); however, this may be due to homogeneity in meniscal health of the specimens limiting the ability for correlations to be detected. Moderate to strong negative correlations between T1 relaxation time and f, and k were found. These relationships should be further explored as T1 is an often neglected imaging metric, and qMT in the meniscus is quite unexplored. T1 was found to have a moderate correlation with T2. These results reinforce that qMT is viable to use in the meniscus, but that further work needs to be done in order to determine if it can be used as a non-invasive method of assessing meniscal tissue mechanical properties