This case study describes the experimental determination of displacements and stresses on a composite model of a pelvis that was modified to represent a healthy intact pelvic ring. The modified model was stressed statically up to 1750 N to simulate standing on one leg and also cyclically to model walking. For two different model settings in the loading machine the values of displacements and stresses at the pelvic ring were determined. The two different settings correspond to two different loading vectors applied on the pelvic ring, boundary conditions and degrees of freedom. The experimentally determined values of displacements in both settings are very similar and in accordance with the knowledge on the behaviour of a real human pelvis. The modified model is thus suitable for testing of newly developed implants for pelvis treatment and experimental determination of displacements and stresses in pelvic ring which are caused by application of implants.

• Klíčová slova
• Pelvic trauma, acetabulum, composite pelvic model, pubic symphysis, sacroiliac joint, stress and displacement in pelvis,
• MeSH
• biomechanika MeSH
• lidé MeSH
• pánev * MeSH
• pánevní kosti * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Intramedullary nailing is already established technique for the treatment of two and three-part fractures of proximal humerus. The aim of the study was to prospectively evaluate the efficacy and functional outcome after treatment of four-part fractures of proximal humerus with Multiloc proximal humeral nail. DESIGN: prospective monocentric cohort study. SETTING: single level 1 traumacenter. MATERIALS AND METHODS: From February 2011 to March 2016, 40 patients with displaced four-part proximal humeral fractures were treated with intramedullary nail inserted through anterolateral approach. Minimum one year follow up completed 35 patients and were involved into the study. RESULTS: After mean follow up period of 25.8 months 29 of 35 fractures healed. Average absolute Constant score in all 35 patients reached 57.7 points, relative side related Constants score 66.8% of contralateral extremity. Together there were 20 complications. in 6 cases (17%) developed complete avascular necrosis of the head. One deep infection was treated by implantation of antibiotic cement discs. Twelve secondary surgeries were performed, mostly for avascular necrosis development. Function and pain were significantly influenced by the quality of fracture reduction (p < 0.05) and development of complete AVN (p = 0.001). Group of 29 patients without AVN reached relative Constant score 73% of contralateral extremity. CONCLUSIONS: Intramedullary nailing can be used as possible fixation technique for the treatment of four-part fractures of proximal humerus. In experienced hands provides nailing osteosynthesis similar results as reconstruction with locking plates. Appropriate reduction of fracture fragments is the key for good functional result. LEVEL OF EVIDENCE: Level 2b - monocentric prospective cohort study.

• Klíčová slova
• Four-Part fracture, Intramedullary nailing, Multiloc PHN, Proximal humerus,
• MeSH
• dospělí MeSH
• fraktury proximálního humeru diagnostické zobrazování   patologie   chirurgie   MeSH
• hojení fraktur fyziologie   MeSH
• intramedulární fixace fraktury metody   MeSH
• lidé středního věku MeSH
• lidé MeSH
• následné studie MeSH
• osteonekróza diagnostické zobrazování   patologie   MeSH
• prospektivní studie MeSH
• radiografie MeSH
• senioři MeSH
• výsledek terapie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH