Stojanka Arsic

The Parametric Model of the Human Mandible Coronoid Process Created by Method of Anatomical Features.

Geometrically accurate and anatomically correct 3D models of the human bones are of great importance for medical research and practice in orthopedics and surgery. These geometrical models can be created by the use of techniques which can be based on input geometrical data acquired from volumetric methods of scanning (e.g., Computed Tomography (CT)) or on the 2D images (e.g., X-ray). Geometrical models of human bones created in such way can be applied for education of medical practitioners, preoperative planning, etc. In cases when geometrical data about the human bone is incomplete (e.g., fractures), it may be necessary to create its complete geometrical model. The possible solution for this problem is the application of parametric models. The geometry of these models can be changed and adapted to the specific patient based on the values of parameters acquired from medical images (e.g., X-ray). In this paper, Method of Anatomical Features (MAF) which enables creation of geometrically precise and anatomically accurate geometrical models of the human bones is implemented for the creation of the parametric model of the Human Mandible Coronoid Process (HMCP). The obtained results about geometrical accuracy of the model are quite satisfactory, as it is stated by the medical practitioners and confirmed in the literature.

Aspects of Orthodontic-Prosthetic Rehabilitation of Dentofacial Anomalies

Skeletal class III malocclusion is one of the most difficult dentofacial anomalies, characterized by deviation in the development of the mandible and maxilla in the sagittal plane, where the mandible is dominant in relation to the maxilla. In patients with class III malocclusion, anomalies in the dentoalveolar level and esthetic discrepancies are also frequent. The etiology of class III malocclusion is multifactorial due to the interaction of hereditary and environmental factors. Rehabilitation and treatment of malocclusion is one of the major goals of modern dentistry. This article presents the orthodontic-prosthetic therapy and rehabilitation of a 45-year-old patient with an abnormal occlusal vertical dimension and a skeletal class III malocclusion. The patient came to the clinic complaining about degraded esthetics and disordered functions of the orofacial region (functions of eating, swallowing, speech) and also pain in the temporomandibular joint. After the diagnosis was made, the patient was first referred to orthodontic treatment with fixed orthodontic appliances (self-ligating brackets system Rot 0.22). Upon completion of the orthodontic treatment, the patient was sent for further prosthetic treatment. Fixed prosthetic restorations were made in the upper and lower jaw, thus achieving a satisfactory result in terms of esthetics and function of the stomatognathic system.

Symptomatic idiopathic noncommunicating intradural arachnoid cyst of the S1 nerve root: a case report.

Study Design. A case report of a rare symptomatic, idiopathic, noncommunicating intradural arachnoid cyst (IAC) of the proximal part of the S1 nerve root (NR). Objective. To discuss the possible pathophysiology, clinical and magnetic resonance imaging (MRI) presentation, intraoperative findings, and follow-up of IAC of the proximal part of the S1 NR. Summary of Background Data. Rare variety of the Naborss Type 3 spinal IAC. The etiopathogenesis are uncertain. Surgical NR decompression with extirpation of the cyst is the treatment of choice. Methods. A 37-year-old woman clinically presented as monoradiculopathy with a 9-month history of progressive, posture-dependent radicular pain, paresthesia and hypoesthesia in the right S1 dermatome, and mild weakness of the ipsilateral plantar flexors. Magnetic resonance imaging (MRI) showed a noncommunicating IAC of the proximal part of the S1 NR on the right side. Surgical exploration through the ipsilateral L5-S1 hemilaminectomy was performed with microsurgical arachnolysis of the compressed and stretched S1 NR fascicles that surrounded the cyst, during which the cyst spontaneously collapsed. The remnant of the cyst wall was extirpated and histopathology confirmed the diagnosis. Results. After surgery an excellent clinical outcome was archived: the leg pain was no longer present and the paraesthesia, hypoesthesia, and motor weakness were resolved within 3 months. At 12 months of follow-up, the patient continues to be completely asymptomatic with no evidence of recurrence on MRI. Conclusion. A rare case of symptomatic, idiopathic, noncommunicating IAC of the proximal part of the S1 NR has been presented. Early recognition and treatment resulted in complete symptom resolution, with preservation of the full working capacity and good quality of life. Isolated monoradiculopathy with progressive, posture-dependent radicular pain seem to be typical clinical findings for such a lesion. Attending physicians should always be mindful of this fact in the total clinical evaluation of such cases.

Obtaining patient-specific point model of the human ilium bone in the case of incomplete volumetric data using the method of parametric regions

In this paper, we present the methodology for determining the point model of the ilium bone in cases when volumetric data of the whole bone are not available. An extreme traumatic bone damage, osteoporosis, destruction of bone tissue by malignant bone tumors or the existence of only 2D medical image (X-ray) can be the reason for the lack of complete volumetric data. Points on the bone surface were defined at the curves that run through 26 previously defined parameters, at the edges of anteroposterior (A–P) and lateral projections and at the parts of the surface between some parameters. Those parts of the surface, enclosed by parameters, represent ten parametric regions. The values of coordinates, which represent the input data in the statistical program, were measured in a uniquely defined coordinate system. After establishing the correlations between the values of coordinates, 8869 different linear and nonlinear regression models were obtained. The prediction values for point coordinates were calculated and exported to a CAD program. Results obtained were tested on a randomly chosen male right ilium bone, applying the methodology for creating the prediction model using the method of parametric regions, which allows creating a complete polygonal model, for each region separately or just for some parts of the region. Results obtained in the form of regression equations for the right ilium bone can be applied to the left ilium bone. The results of the research were verified using a comparative deviation and distance analysis between the initial and obtained polygonal models.

Fractures of Joint Ankle

Fractures of Joint Ankle Joint ankle represents one of the most complicated anatomic-functional structures of locomotoric apparatus. Upper joint ankle (talocruralis) bind low tip-end of shank (tibia) and fibula with joint bone (talus) and represent joint among the bones of shank and foot bones. Upper joint ankle joint together with lower ankle joint acts like functional, anatomical and clinical entity not only in physiological conditions but as well in injuries. These injuries cause not only damages of bone structure but also of ligaments and soft structures. Fractures of maleolus as the most frequent of low extremities represent 10-12% of all fractures. As the most frequent mechanism of injury of joint ankle the inversion of foot is stated when it is in supination and adduction. This analysis had 151 patient who had joint ankle fracture both sexes, age 18-45, and among them there were 102 men (67.55%) and 49 women (32.45%). The patients whose diagnosis was joint ankle fracture were observed in Orthopedic - Casualty ward of Clinical Centre in Podgorica. The research period was May 2005-May 2009. The results of our research show that the most frequently fractures of joint ankle happened while running 52 patients (34.44%) and the least by fall from the height 22 (14.57%). The most frequent fracture type was SE type 48 (31.79%) and the least PA type 25 (16.56%).