With continually growing availability of high performance computing resources, the finite element methods (FEM) are becoming increasingly more efficient and practical research tools. In the domain of computational biomechanics, FEMs have been successfully applied in investigation of biomedical problems that include impact and fracture mechanics of bone, load transmission through the joints, feasibility of joint replacements, and many others. The present research study was concerned with the development of a detailed, anatomically accurate, finite element model of the human hand and wrist. As a first step in this direction, we used a publically available database of wrist bone anatomy and carpal kinematics to construct a multi-body statistical shape model (SSM) of the wrist. The resulting model provides an efficient parameterization of anatomical variations of the entire training set and can thus overcome the major shortcoming of conventional biomechanical models associated with limited generalization ability. The main contributions of this work are: 1) A robust method for constructing multi-body SSM of the wrist from surface meshes. 2) A novel technique for resampling closed genus-0 meshes to produce high quality triangulations suitable for finite element simulations. Additionally, all techniques developed in the course of this study could be directly applied to create an equivalent model of the tarsus.

Introdução: Ao analisar a osteoartrose pós-traumática do punho a literatura demonstra que sua etiologia é, na maioria das vezes, secundária a lesões ligamentares ou a fraturas do carpo que, por sua vez, seguem um padrão definido e evolutivo de acometimento articular do punho. Várias abordagens cirúrgicas são descritas para o tratamento da osteoartrose pós-traumática do carpo. Considerando a carpectomia proximal e a artrodese dos quatro cantos, a literatura apresenta apenas estudos retrospectivos comparando os resultados funcionais entre as técnicas. O objetivo desta tese é comparar os resultados funcionais entre a carpectomia proximal e a artrodese dos quatro cantos no tratamento da osteoartrose pós-traumática do punho, sem acometimento da articulação mediocárpica. Método: Neste estudo prospectivo e randomizado 20 pacientes portadores de osteoartrose pós-traumática sem acometimento da articulação mediocárpica do punho, submetidos à carpectomia proximal ou a artrodese dos quatro cantos tiveram seus dados pós-operatórios analisados e comparados. Resultados: Todos os pacientes deste estudo referiram melhora da dor e da sua capacidade funcional. Em todos os casos houve diminuição dos valores pré e pós-operatórios de goniometria em ambos os procedimentos. Não houve diferença estatisticamente significante entre os procedimentos. Conclusão: Com relação aos resultados funcionais, a carpectomia proximal e a artrodese dos quatro cantos são procedimentos efetivos e semelhantes no tratamento dos pacientes portadores de SLAC/SNAC WRIST sem acometimento da articulação mediocárpica. / Introduction: Wrist arthritis results most of the times from ligaments tears or carpal bones fractures. Many surgical procedures are described in literature. Regarding proximal row carpectomy and four corner arthrodesis, there are only retrospective studies available in literature. The objective of this study is to compare the functional results between these two surgical procedures. Method: In this prospective and randomized study 20 patients underwent proximal row carpectomy or four corner arthrodesis for the treatment of wrist arthritis. In all patients the midcarpal joints were free of lesions. Functional results were compared. Results: Both proximal row carpectomy and four corner arthrodesis improved pain. All cases showed decreased range of motion after surgery. The differences between the groups were not statistically significant. Conclusion: Regarding functional results both procedures were similar and improved pain in patients with SLAC/SNAC WRIST without degenerative changes in midcarpal joint.

Introdução: Ao analisar a osteoartrose pós-traumática do punho a literatura demonstra que sua etiologia é, na maioria das vezes, secundária a lesões ligamentares ou a fraturas do carpo que, por sua vez, seguem um padrão definido e evolutivo de acometimento articular do punho. Várias abordagens cirúrgicas são descritas para o tratamento da osteoartrose pós-traumática do carpo. Considerando a carpectomia proximal e a artrodese dos quatro cantos, a literatura apresenta apenas estudos retrospectivos comparando os resultados funcionais entre as técnicas. O objetivo desta tese é comparar os resultados funcionais entre a carpectomia proximal e a artrodese dos quatro cantos no tratamento da osteoartrose pós-traumática do punho, sem acometimento da articulação mediocárpica. Método: Neste estudo prospectivo e randomizado 20 pacientes portadores de osteoartrose pós-traumática sem acometimento da articulação mediocárpica do punho, submetidos à carpectomia proximal ou a artrodese dos quatro cantos tiveram seus dados pós-operatórios analisados e comparados. Resultados: Todos os pacientes deste estudo referiram melhora da dor e da sua capacidade funcional. Em todos os casos houve diminuição dos valores pré e pós-operatórios de goniometria em ambos os procedimentos. Não houve diferença estatisticamente significante entre os procedimentos. Conclusão: Com relação aos resultados funcionais, a carpectomia proximal e a artrodese dos quatro cantos são procedimentos efetivos e semelhantes no tratamento dos pacientes portadores de SLAC/SNAC WRIST sem acometimento da articulação mediocárpica. / Introduction: Wrist arthritis results most of the times from ligaments tears or carpal bones fractures. Many surgical procedures are described in literature. Regarding proximal row carpectomy and four corner arthrodesis, there are only retrospective studies available in literature. The objective of this study is to compare the functional results between these two surgical procedures. Method: In this prospective and randomized study 20 patients underwent proximal row carpectomy or four corner arthrodesis for the treatment of wrist arthritis. In all patients the midcarpal joints were free of lesions. Functional results were compared. Results: Both proximal row carpectomy and four corner arthrodesis improved pain. All cases showed decreased range of motion after surgery. The differences between the groups were not statistically significant. Conclusion: Regarding functional results both procedures were similar and improved pain in patients with SLAC/SNAC WRIST without degenerative changes in midcarpal joint.

<p>Scaphoid fracture is most common in young individuals of working age. Without adequate diagnosis and treatment, long-term results are poor. Operative treatment is being recommended increasingly often instead of a long time in cast, although there is no evidence-based support for its superiority.</p><p>The present thesis focuses on diagnostic problems and therapeutic consequences of acute scaphoid fractures and of scaphoid reconstruction when other treatments have failed.</p><p>Simultaneous plain radiographs and computed tomography were done in 97 injured wrists. Structural assessments of plain radiography images were highly predictive with respect to the risk of having a displaced or comminute fracture as diagnosed on computed tomography. Any finding of a gap or step-off > 0.5 mm, the presence of an intermediate fragment or a dorsal lunate tilt of ≥ 15° identified 81 % of fractures that were displaced or comminuted when investigated with computed tomography.</p><p>Eighty-three patients were randomly allocated to and received either nonoperative treatment in cast or operative treatment with the aim of assessing long-term outcome of the two treatment options. Fifty-two of the patients were occupationally active. From an occupational perspective with an early return to work, surgical treatment was superior in individuals with manual employment, and from a health economic perspective conservative treatment was superior in non-manual workers.</p><p>Patients treated for scaphoid fractures generally do well up to 13 years after the injury based on limb-specific outcome scores. No benefits were identified with operative treatment compared to non-operative treatment in cast. On the contrary, there was an increased risk for osteoarthritis in the scaphotrapezial joint in those who were operated.</p><p>The patient-rated long-term results of silicone implant arthroplasty were good, with pain relief and reasonable hand function in many patients up to 20 years after surgery.</p>

Scaphoid fracture is most common in young individuals of working age. Without adequate diagnosis and treatment, long-term results are poor. Operative treatment is being recommended increasingly often instead of a long time in cast, although there is no evidence-based support for its superiority. The present thesis focuses on diagnostic problems and therapeutic consequences of acute scaphoid fractures and of scaphoid reconstruction when other treatments have failed. Simultaneous plain radiographs and computed tomography were done in 97 injured wrists. Structural assessments of plain radiography images were highly predictive with respect to the risk of having a displaced or comminute fracture as diagnosed on computed tomography. Any finding of a gap or step-off &gt; 0.5 mm, the presence of an intermediate fragment or a dorsal lunate tilt of ≥ 15° identified 81 % of fractures that were displaced or comminuted when investigated with computed tomography. Eighty-three patients were randomly allocated to and received either nonoperative treatment in cast or operative treatment with the aim of assessing long-term outcome of the two treatment options. Fifty-two of the patients were occupationally active. From an occupational perspective with an early return to work, surgical treatment was superior in individuals with manual employment, and from a health economic perspective conservative treatment was superior in non-manual workers. Patients treated for scaphoid fractures generally do well up to 13 years after the injury based on limb-specific outcome scores. No benefits were identified with operative treatment compared to non-operative treatment in cast. On the contrary, there was an increased risk for osteoarthritis in the scaphotrapezial joint in those who were operated. The patient-rated long-term results of silicone implant arthroplasty were good, with pain relief and reasonable hand function in many patients up to 20 years after surgery.