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1.
PLoS One ; 19(7): e0307538, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39028745

RESUMEN

This study explored the impact of landing height on the tibiofemoral joint's medial compartment force (MCF) during drop jumps to help athletes prevent knee injury. Experienced male participants (N = 16) performed drop jumps with landing heights from 0.15 m to 0.75 m. Kinematic/kinetic parameters were collected using a motion capture system and a three-dimensional force platform. The Med-Lat Knee model was used to calculate biomechanical indicators of the knee joint, and data were analyzed using one-way analysis of variance and one-dimensional statistical parametric mapping (SPM1d). Findings indicated that landing height significantly affected the anterior-posterior and vertical MCF, flexion-extension torque, internal-external rotation torque, and vertical ground reaction force (p<0.05)-all increasing with elevated landing height-and significantly impacted the generated force of the vastus medialis, vastus lateralis, and vastus intermedius (p<0.05). SPM1d analysis confirmed these results within specific time intervals. Thus, both the knee moment and the MCF exhibited similar coordinated changes during drop jumps, indicating that these may be adaptive movement strategy. The impact of varying drop jump heights on muscle groups around the knee joint varied suggests that different heights induce specific muscular responses and improve muscle coordination to prevent knee joint injuries.


Asunto(s)
Traumatismos de la Rodilla , Articulación Tibiofemoral , Torque , Humanos , Articulación Tibiofemoral/fisiología , Tibia/fisiología , Fémur/fisiología , Músculo Esquelético , Fenómenos Biomecánicos , Traumatismos de la Rodilla/prevención & control , Adulto
2.
J Appl Biomech ; 40(4): 270-277, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38834183

RESUMEN

Imbalanced joint load distribution across the tibiofemoral surface is a risk factor for osteoarthritic changes to this joint. Lateral wedge insoles, with and without arch support, are a form of biomechanical intervention that can redistribute tibiofemoral joint load, as estimated by external measures of knee load. The objective of this study was to examine the effect of these insoles on the internal joint contact characteristics of osteoarthritic knees during weightbearing. Fifteen adults with tibiofemoral osteoarthritis underwent magnetic resonance imaging of the affected knee, while standing under 3 insole conditions: flat control, lateral wedge alone, and lateral wedge with arch support. Images were processed, and the surface area and centroid location of joint contact were quantified separately for the medial and lateral tibiofemoral compartments. Medial contact surface area was increased with the 2 lateral wedge conditions compared with the control (P ≤ .012). A more anterior contact centroid was observed in the medial compartment in the lateral wedge with arch support compared with the lateral wedge alone (P = .009). Significant changes in lateral compartment joint contact outcomes were not observed. These findings represent early insights into how loading at the tibiofemoral interface may be altered by lateral wedge insoles as a potential intervention for knee osteoarthritis.


Asunto(s)
Ortesis del Pié , Osteoartritis de la Rodilla , Soporte de Peso , Humanos , Osteoartritis de la Rodilla/fisiopatología , Osteoartritis de la Rodilla/diagnóstico por imagen , Femenino , Masculino , Persona de Mediana Edad , Articulación de la Rodilla/fisiopatología , Articulación de la Rodilla/diagnóstico por imagen , Anciano , Imagen por Resonancia Magnética , Fenómenos Biomecánicos , Articulación Tibiofemoral
3.
J ISAKOS ; 9(4): 562-567, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38636904

RESUMEN

OBJECTIVE: To determine the mean contact pressure, peak contact pressure, and mean contact area of the lateral tibiofemoral joint in lateral extra-articular tenodesis (LET) with tension on the graft in tibial neutral and external rotation. METHODS: A total of eight Thiel-embalmed cadaveric knees were prepared and divided into two groups (4 knees in each group): the LET-NR group (lateral extra-articular tenodesis tension in neutral rotation) and (2) the LET-ER group (lateral extra-articular tenodesis tension in external rotation). Each knee was prepared according to the corresponding technique. A hydraulic testing system (E10000, Instron) simulates an axial load of 735 â€‹N for 10 â€‹s in each group. RESULTS: The LET-ER group exhibited a statistically significant higher peak contact pressure compared to the LET-NR group. The peak contact pressure values in the LET-NR and LET-ER groups were 702.3 â€‹± â€‹233.9 â€‹kPa and 1235.5 â€‹± â€‹171.4 â€‹kPa, respectively (p â€‹= â€‹0.010, 95% CI, -888.0 to -178.5). The mean contact pressure values in the LET-NR and LET-ER groups were 344.9 â€‹± â€‹69.0 â€‹kPa and 355.3 â€‹± â€‹34.9 â€‹kPa, respectively (p â€‹= â€‹0.796, 95% CI, -105.1-84.2). The mean contact area values in the LET-NR and LET-ER groups were 36.8 â€‹± â€‹3.1 mm2 and 33.3 â€‹± â€‹6.4 mm2, respectively (p â€‹= â€‹0.360, 95% CI, -5.2-12.2). CONCLUSIONS: The peak contact pressure of the lateral tibiofemoral joint is greater in LET when the graft is tensioned in external rotation than in neutral rotation. However, no statistically significant difference in the mean contact pressure or the mean contact area was observed between the two groups. LEVEL OF EVIDENCE: III.


Asunto(s)
Presión , Tenodesis , Tibia , Articulación Tibiofemoral , Humanos , Fenómenos Biomecánicos , Cadáver , Fémur/cirugía , Rango del Movimiento Articular , Rotación , Tenodesis/métodos , Tibia/cirugía , Articulación Tibiofemoral/cirugía , Soporte de Peso/fisiología
4.
J Am Acad Orthop Surg ; 32(11): e558-e567, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38669669

RESUMEN

INTRODUCTION: The purpose of this study was to determine how variations in lower limb alignment affect tibiofemoral joint contact biomechanics in the setting of medial meniscus posterior root tear (MMPRT) and associated root repair. METHODS: A finite-element model of an intact knee joint was developed. Limb alignments ranging from 4° valgus to 8° varus were simulated under a 1,000 N compression load applied to the femoral head. For the intact, MMPRT, and root repair conditions, the peak contact pressure (PCP), total contact area, mean and maximum local contact pressure (LCP) elevation, and total area of LCP elevation of the medial tibiofemoral compartment were quantified. RESULTS: The PCP and total contact area of the medial compartment in the intact knee increased from 2.43 MPa and 361 mm 2 at 4° valgus to 9.09 MPa and 508 mm 2 at 8° of varus. Compared with the intact state, in the MMPRT condition, medial compartment PCP was greater and the total contact area smaller for all alignment conditions. Root repair roughly restored PCPs in the medial compartment; however, this ability was compromised in knees with increasing varus alignment. Specifically, elevations in PCP relative to the intact state increased with increasing varus, as did the total contact area with LCP elevation. After root repair, medial compartment PCP remained elevated above the intact state at all degrees tested, ranging from 0.05 MPa at 4° valgus to 0.27 MPa at 8° of varus, with overall PCP values increasing from 2.48 to 9.09 MPa. For varus alignment greater than 4°, root repair failed to reduce the total contact area with LCP elevation relative to the MMPRT state. DISCUSSION: Greater PCPs and areas of LCP elevation in varus knees may reduce the clinical effectiveness of root repair in delaying or preventing the development of tibiofemoral osteoarthritis.


Asunto(s)
Análisis de Elementos Finitos , Articulación de la Rodilla , Meniscos Tibiales , Lesiones de Menisco Tibial , Humanos , Fenómenos Biomecánicos , Lesiones de Menisco Tibial/cirugía , Lesiones de Menisco Tibial/fisiopatología , Articulación de la Rodilla/fisiopatología , Articulación de la Rodilla/cirugía , Meniscos Tibiales/cirugía , Meniscos Tibiales/fisiopatología , Tibia/cirugía , Extremidad Inferior/fisiopatología , Extremidad Inferior/cirugía , Fémur/cirugía , Articulación Tibiofemoral
5.
Ann Biomed Eng ; 52(5): 1393-1402, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38446329

RESUMEN

Osteochondral grafting has demonstrated positive outcomes for treating articular cartilage defects by replacing the damaged region with a cylindrical graft consisting of bone with a layer of cartilage. However, factors that cause graft subsidence are not well understood. The aim of this study was to develop finite element (FE) models of osteochondral grafts within a tibiofemoral joint, suitable for an investigation of parameters affecting graft stability. Cadaveric femurs were used to experimentally calibrate the bone properties and graft-bone frictional forces for use in corresponding image-based FE models, generated from µCT scan data. Effects of cartilage defects and osteochondral graft repair were measured by examining contact pressure changes using further in vitro tests. Here, six defects were created in the femoral condyles, which were subsequently treated with osteochondral autografts or metal pins. Matching image-based FE models were created, and the contact patches were compared. The bone material properties and graft-bone frictional forces were successfully calibrated from the initial tests with good resulting levels of agreement (CCC = 0.87). The tibiofemoral joint experiment provided a range of cases that were accurately described in the resultant pressure maps and were well represented in the FE models. Cartilage defects and repair quality were experimentally measurable with good agreement in the FE model pressure maps. Model confidence was built through extensive validation and sensitivity testing. It was found that specimen-specific properties were required to accurately represent graft behaviour. The final models produced are suitable for a range of parametric testing to investigate immediate graft stability.


Asunto(s)
Cartílago Articular , Articulación Tibiofemoral , Humanos , Análisis de Elementos Finitos , Cartílago Articular/diagnóstico por imagen , Cartílago Articular/cirugía , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Huesos
6.
Sci Rep ; 14(1): 1379, 2024 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-38228640

RESUMEN

Knee osteoarthritis (OA) is a public health problem affecting millions of people worldwide. The intensity of the tibiofemoral contact forces is related to cartilage degeneration, and so is the importance of quantifying joint loads during daily activities. Although simulation with musculoskeletal models has been used to calculate joint loads, it demands high-cost equipment and a very time-consuming process. This study aimed to evaluate consolidated machine learning algorithms to predict tibiofemoral forces during gait analysis of healthy individuals and knee OA patients. Also, we evaluated three different datasets to train each model, considering different combinations of primary kinematic and kinetic data, and post-processing data. We evaluated 14 patients with severe unilateral knee OA and 14 healthy individuals during 3-5 gait trials. Data were split into 70% and 30% of the samples as training and test data. Test data was independently evaluated considering a mixture of pathological and healthy individuals, and only OA and Control patients. The main results showed that accurate predictions of the tibiofemoral contact forces were achieved using machine learning methods and that the predictions were sensitive to changes in the input data as training. The present study provided insights into the most promising regressions methods to predict knee contact forces representing an important starting point for the broader application of biomechanical analysis in clinical environments.


Asunto(s)
Osteoartritis de la Rodilla , Articulación Tibiofemoral , Humanos , Marcha , Articulación de la Rodilla , Rodilla , Fenómenos Biomecánicos
7.
J Orthop Surg Res ; 19(1): 43, 2024 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-38184619

RESUMEN

BACKGROUND: The purpose of this study was to investigate the influence of different residual meniscus volume on the biomechanics of tibiofemoral joint after discoid lateral meniscus (DLM) surgery by finite element analysis. METHODS: A knee joint model was established based on CT and MRI imaging data. The DLM model was divided into five regions according to conventional meniscectomy, with volumes of 15%, 15%, 15%, 15%, 15%, and 40% for each region. Additionally, the DLM model was divided into anterior and posterior parts to obtain ten regions. The DLM was resected according to the design scheme, and together with the intact discoid meniscus, a total of 15 models were obtained. Finite element analysis was conducted to assess shear and pressure trends on the knee joint. RESULTS: The study observed significant changes in peak shear stress and compressive stress in the lateral meniscus and lateral femur cartilage. As the meniscus volume decreased, there was an increase in these stresses. Specifically, when the meniscus volume reduced to 40%, there was a sharp increase in shear stress (302%) and compressive stress (152%) on the meniscus, as well as shear stress (195%) and compressive stress (157%) on the lateral femur cartilage. Furthermore, the model grouping results showed that preserving a higher frontal volume in the meniscus model provided better biomechanical advantages. CONCLUSION: The use of finite element analysis has demonstrated that preserving more than 55% of the meniscus volume is necessary to prevent a significant increase in joint stress, which can potentially lead to joint degeneration. Additionally, it is crucial to preserve the front volume of the DLM in order to achieve improved knee biomechanical outcomes.


Asunto(s)
Meniscos Tibiales , Articulación Tibiofemoral , Fenómenos Biomecánicos , Análisis de Elementos Finitos , Meniscos Tibiales/diagnóstico por imagen , Meniscos Tibiales/cirugía , Volumen Residual , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía
8.
Arthroscopy ; 40(3): 896-897, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38219141

RESUMEN

Medial opening-wedge high tibial osteotomies are commonly performed to treat varus deformity and medial compartment osteoarthritis of the knee in active younger individuals. A common complication of this procedure is the development of a lateral hinge fracture. This can occur both acutely and with a delayed presentation. There are many considerations to reduce this fracture, including biplanar versus monoplanar osteotomy, amount of correction/gap width, level of the osteotomy, and lateral cortical distance of the osteotomy. To best reduce the risk of a lateral hinge fracture, place the level of the osteotomy at the level of the proximal tibiofibular joint, and maintain a gap width of no larger than ∼11 mm.


Asunto(s)
Fracturas Óseas , Osteoartritis de la Rodilla , Humanos , Tibia/cirugía , Articulación Tibiofemoral , Osteoartritis de la Rodilla/cirugía , Articulación de la Rodilla/cirugía , Osteotomía/efectos adversos , Osteotomía/métodos
9.
Skeletal Radiol ; 53(2): 329-338, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37466645

RESUMEN

PURPOSE: To analyze the accuracy of MRI in diagnosis of distal tibiofibular syndesmosis instability (DTSI) and construct new diagnostic parameters. MATERIALS AND METHODS: This retrospective study evaluated 212 patients with history of ankle sprains and 3 T MRI and received a final diagnosis of distal tibiofibular syndesmosis instability by ankle arthroscopic surgery from October 2017 and December 2021. We compared the accuracy of syndesmotic injury, qualitative index of distal tibiofibular joint effusion (DTJE), and quantitative index of distal tibiofibular joint effusion (DTJE) in diagnosing distal tibiofibular syndesmosis instability. The criteria for syndesmotic injury were consistent with previous literature, and DTJE was grouped according to the pre-experimental results. RESULTS: A total of 212 patients (mean age, 35.64 ± 11.79, 74 female and 138 male) were included. Independent predictive MRI features included syndesmotic injury, qualitative index of distal tibiofibular joint effusion, and quantitative index of DTJE including the height, projected area of equal-point method, and projected area of incremental-value method. The quantitative index of DTJE showed a higher area under the receiver operating characteristic curve (0.805/0.803/0.804/0.811/0.817/0.805 > 0.8, P < 0.05; in comparison with all other method). The height measurement method was simpler and easier to operate, that could be gotten only by measuring the DTJE distance of a MRI independent layer, and the cut-off value of the effusion height was 8.00 mm and the Youden index (0.56) was the best. CONCLUSIONS: Our research translated a complicated string of MRI multi-dimensional spatial measurements into a simple measuring process, and established the significance of quantifying DTJE in the diagnosis of DTSI. We found that the 8-mm height of DTJE was a more specific indicator for DTSI and could serve as a novel MRI diagnostic cutoff in clinical practice.


Asunto(s)
Traumatismos del Tobillo , Inestabilidad de la Articulación , Humanos , Masculino , Femenino , Articulación del Tobillo/diagnóstico por imagen , Articulación del Tobillo/cirugía , Tobillo , Estudios Retrospectivos , Articulación Tibiofemoral , Traumatismos del Tobillo/complicaciones , Inestabilidad de la Articulación/diagnóstico por imagen , Inestabilidad de la Articulación/etiología
10.
Artículo en Inglés | MEDLINE | ID: mdl-38170588

RESUMEN

BACKGROUND: The fact that lateral malleolar fracture is accompanied by posterior malleolar fracture may adversely affect syndesmosis malreduction rates. We aimed to compare syndesmosis malreduction rates determined on postoperative radiographs between isolated lateral malleolar fractures and lateral malleolar fractures accompanied by posterior malleolar fractures. METHODS: We retrospectively examined 128 operative patients: 73 with isolated lateral malleolar fractures (group L) and 55 with lateral + posterior malleolar fractures (group LP). In group LP, no patients received posterior fragment fixation. In both groups, indirect syndesmosis fixation was performed with a single screw after open reduction and internal fixation of the lateral malleolus. Patient age, sex, fracture side, fracture type (Lauge-Hansen and Danis-Weber classifications), Kellgren-Lawrence osteoarthritis classification, syndesmotic incongruency on postoperative radiographs, syndesmotic malreduction of postoperative fibula fracture, fracture union time, complication rates, accompanying injuries, and preoperative and postoperative radiographic syndesmotic measurements (tibiofibular overlap, tibiofibular clear space, medial clear space) were recorded, and the groups were compared. RESULTS: Mean ± SD age was 44.32 ± 15.66 years in group L and 48.93 ± 14.03 years in group LP (P = .087). There were no significant differences in preoperative and postoperative tibiofibular distance, tibiofibular overlap, and medial clear space values between groups (P > .05). The prevalence of grade 2 fractures according to the Kellgren-Lawrence classification was significantly higher in group LP (P = .047). Postoperative syndesmosis malreduction was detected in 12 patients in group L and in nine in group LP (P = .991). CONCLUSIONS: In lateral malleolar fractures accompanied by small-fragment posterolateral or avulsion-type posterior malleolar fractures, closed syndesmotic screw fixation does not cause syndesmosis malreduction.


Asunto(s)
Fracturas de Tobillo , Traumatismos del Tobillo , Humanos , Adulto , Persona de Mediana Edad , Estudios Retrospectivos , Tornillos Óseos , Articulación Tibiofemoral , Fijación Interna de Fracturas/efectos adversos , Tomografía Computarizada por Rayos X , Fracturas de Tobillo/diagnóstico por imagen , Fracturas de Tobillo/cirugía , Traumatismos del Tobillo/complicaciones , Traumatismos del Tobillo/diagnóstico por imagen , Traumatismos del Tobillo/cirugía , Articulación del Tobillo/cirugía , Resultado del Tratamiento
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