ABSTRACT
@#In the stomatognathic system, a stable jaw position is influenced by occlusion, the temporomandibular joint and neuromuscular stability. The condylar position in the glenoid fossa is closely related to the jaw position, while no consensus has been reached on the optimum jaw position and its corresponding condylar position in oral therapy. This paper summarizes the controversial opinions regarding the selection of jaw position and the corresponding condylar position in prosthetics and orthodontics, including antero-superior, antero-inferior, and therapeutic positions. Their indications, theoretical bases and clinical applications are also included. The literature review results suggest that, the antero-superior position, in other words, centric relation, should be chosen when the patient has a stable jaw position without TMD. In cases where finding an ideal antero-superior position is difficult due to hyperplasia or deformation or disarrangement of the articular disc, the antero-inferior position is recommended to alleviate symptoms and facilitate reconstruction of the TMJ to obtain good stability. Moreover, for high-angle patients with Class Ⅱ malocclusion or for patients with mild skeletal malocclusion, camouflaged orthodontic treatment combined with antero-inferior jaw repositioning through the potential of condyle remodeling can be an alternative to orthognathic surgery and can simplify the treatment plan. While the therapeutic position is specifically proposed for coping with complicated situations related to cranio-mandibular dysfunction, such as maximal intercuspal position abnormalities or deflection, muscle and TMJ dysfunction, unstable jaw position, in which changes in the original occlusion or abnormal TMJ guidance are induced, and a new intercuspal position can be established and stabilized on the basis of occlusal support and modified guidance. The therapeutic position put aside the debate regarding condylar position, however, the specific position of the condyle has not been reported in this case. This review suggests that different jaw positions and condylar positions have different scopes of application, and their clinical selection should be based on based on whether the patient′s joints have organic changes and the stability of the jaw positions should be comprehensively considered. However, the long-term effects of oral therapy based on different jaw positions need to be further verified by controlled clinical trials in the future.
ABSTRACT
Introducción: El abordaje suboccipital retrosigmoideo es la vía principal para la resección de los schwannomas vestibulares (SV). La relación vascular más constante de los nervios del conducto auditivo interno es la arteria cerebelosa anteroinferior (ACAI); pudiendo su recorrido presentarse como un serio obstáculo para la resección completa de la lesión. Descripción del caso: Paciente varón de 38 años, con diagnóstico presuntivo de SV por resonancia magnética (Grado T3B). Se realiza cirugía por vía retrosigmoidea. Se observa a la ACAI totalmente recubierta por tejido dural y óseo, cuya liberación fue posible mediante fresado en la fosa subarcuata. Se logra una exéresis completa del tumor. El paciente evolucionó durante el estado posoperatorio sin déficit neurológico agregado. Discusión: La ACAI ha sido descripta fijada a la duramadre y/o incrustada en el hueso de la fosa subarcuata en escasas publicaciones, impidiendo la resección completa de un SV, especialmente de la porción intracanalicular. Sin embargo, su liberación supone riesgo adicional de lesión vascular. Conclusión: La lesión de la ACAI puede ser causal de alta morbilidad, por lo que el neurocirujano debe estar preparado para reconocer y resolver este tipo de situaciones.
Introduction: A retrosigmoid suboccipital approach is the route most commonly utilized to resect vestibular schwannomas (VS). However, the anterior inferior cerebellar artery (AICA) usually runs adjacent to internal auditory canal nerves, and its course may severely impede total tumor resection. Case report: A 38-year-old male patient presented with presumed grade T3B VS, diagnosed by magnetic resonance imaging (MRI). Surgery was performed using a retrosigmoid approach, during which the AICA was identified to be completely covered by dural and bone tissue. Further drilling in the subarcuate fossa was necessary to release the AICI, allowing for total gross resection of the VS. No neurological deficits were observed post-operatively. Discussion: On rare occasion, the AICA has been described fixed to the dura and/or embedded within subarcuate fossal bone, thereby preventing removal of the intra-canalicular portion of the VS and, hence, total resection. However, AICA release adds the risk of vascular injury. Conclusion: Injury to the AICA may cause high morbidity in patients with a vestibular schwannoma. Neurosurgeons must be able to recognize and deal with certain anatomical configurations that place patients at particularly-high risk.
Subject(s)
Humans , Neurilemmoma , Arteries , Neuroma, Acoustic , Ear CanalABSTRACT
Se realizó una revisión bibliográfica sobre las lesiones traumáticas de la articulación tibioperonea distal. Se recuerda y actualiza sobre aspectos como: anatomía, mecanismo de producción y cuadro clínico. Reciben especial énfasis los estudios imagenológicos y se subraya el uso e interpretación de la radiografía simple. Para terminar esta revisión se exponen las variantes de tratamiento tanto para las lesiones ligamentosas aisladas o asociadas a fractura del tobillo y su manejo posoperatorio.
A bibliographic review on the traumatic injuries of the distal tibiofibular joint was made. Aspects such as anatomy, mechanism of production and clinical picture were reminded and updated. The imaging studies were specially emphasized and the use and interpretation of the simple X-ray was underlined. To conclude this review, the variants of the treatment for isolated ligamentous injuries or for those associated with the ankle fracture, as well as their postoperative management, were exposed.