RESUMEN
We present a three dimensional finite element analysis of stress distribution and menisci deformation in the human knee joint. The study is based on the Open Knee model with the geometry of the lateral meniscus which shows some degenerative disorders. The nonlinear analysis of the knee joint under compressive axial load is performed. We present results for intact knee, knee with complete radial posterior meniscus root tear and knee with total meniscectomy of medial or lateral meniscus. We investigate how the meniscus shape in the cross sectional plane influences knee-joint mechanics by comparing the results for flat (degenerated) lateral and normal medial meniscus. Specifically, the deformation of the menisci in the coronal plane and the corresponding stress values in cartilages are studied. By analysing contact resultant force acting on the menisci in axial plane we have shown that restricted extrusion of the torn lateral meniscus can be attributed to small slope of its cross section in the coronal plane. Additionally, the change of the contact area and the resultant force acting on the menisci as the function of compressive load are investigated.
Asunto(s)
Meniscos Tibiales/fisiopatología , Fenómenos Biomecánicos , Cartílago Articular/patología , Cartílago Articular/fisiopatología , Simulación por Computador , Análisis de Elementos Finitos , Humanos , Imagenología Tridimensional , Rodilla/fisiopatología , Traumatismos de la Rodilla/patología , Traumatismos de la Rodilla/fisiopatología , Meniscos Tibiales/patología , Modelos BiológicosRESUMEN
Between 1995-2003 84 patients were treated because of the tibial plateau fracture in the Department of Orthopaedics of Gdansk Medical University. 47 patients were evaluated at the follow-up. In the pure cleavage fractures after joint opening an open reduction and internal fixation via screws or buttress plate was performed. In the cleavage fractures combined with depression the treatment consisted of: open reduction, elevation of the depressed plateau "en mass", bone grafting of the metaphysis, fixation of the fracture with cancellous screws and buttress plating. Rasmussen modified scale was used to assess the outcome. Resnick and Niwoyama criteria were used in calculating the degree of the degenerative changes. The clinical results were very good in 5 patients, good in 26, fair in 9 and poor in 5 patients. In the radiological assessment a very good result were observed in 8 patients, good in 28, fair in 7 and poor in 4 patients. An anatomical reduction of the articular surface together with stable internal fixation of the fracture site decreases the risk of the degenerative changes and helps to achieve a good final result.
Asunto(s)
Fijación Interna de Fracturas/métodos , Fracturas de la Tibia/cirugía , Adulto , Anciano , Artroscopía , Placas Óseas , Trasplante Óseo , Femenino , Estudios de Seguimiento , Fijación Interna de Fracturas/instrumentación , Curación de Fractura , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Radiografía , Fracturas de la Tibia/diagnóstico por imagen , Resultado del TratamientoRESUMEN
Traumatic anterior shoulder instability is the most common type of shoulder instability. Treatment is surgical and there is no single best procedure. Arthroscopic Bankart repair restores stability by reattaching the labrum or capsule directly to the anterior glenoid rim. The aim of the study was to assess the clinical value of the arthroscopic Bankart repair. Between 2001 and 2005 twenty eight patients with traumatic anterior shoulder instability were treated. During the operation the capsulolabral tissue was mobilized from the anterior glenoid rim and neck of scapula, then 3 Mitek suture anchors were inserted and the labrum was sutured to the anterior glenoid rim. The patients were clinically evaluated according to MISS questionnaire. Up till now the recurrence of the anterior shoulder instability were not seen in the 25 patients operated with the aforementioned method. MISS questionnaire values were significantly higher following the surgery. Arthroscopic Bankart repair restores joint stability, helps to avoid complications associated With opening of the shoulder and gives a better cosmetic effect.