BACKGROUND: The acromion projects laterally in a curving orientation. When a fracture of the acromion occurs, despite being rare, matching the best-fit fixation plate is challenging due to few options and limited availability of fixation plate types. Alternative fixation methods can carry risk of nonunion complications. PURPOSE: The objective of this study was to investigate the morphological curvature pattern of the acromion to assess the level of the fixation plates fitness and provide the suitable imaging modalities for evaluating the acromion curvature. BASIC PROCEDURES: The correlation between the acromion curvature and five fixation plates were calculated and their fitness level was evaluated statistically. The curvature of acromion and the five available fixation plates were photographed and assessed digitally by software (FIJI ImageJ and Microsoft Excel). The method entails plotting seven points along the curving surface and margins of the acromion, while the Excel Solver function calculates the regression, ultimately giving curvature values. First, the acromion parameters were studied on 180 paired healthy dry scapulae. Then, the acromion curvature values were compared to the fixation plates curvatures. Likewise, the acromion curvature was assessed as applicable on 153 (100 AP- views, 50 Y- views, and 3 superior-views) retrospective plain X-rays and 40 3D-CT scapula reconstructions of healthy acromia. MAIN FINDINGS: The mean length of the acromion was 48.70 ± 5.29 mm, mean thickness was 8.51 ± 1.67 mm, and mean width was 25.97 ± 5.97 mm. The calculated values of the mean curvatures were 0.050 ± 0.015 mm-1 for the mean acromion surface, 0.042 ± 0.027 mm-1 for the internal margin, and 0.055 ± 0.010 mm-1 for the external margin. The curved geometry of the acromion was plotted on a graph giving a spectrum of curvature patterns with distribution values revealing fixation plates fitness represented by area under the curve with frequencies of 4.32 % for the acromion-specific fixation plate, 14.28 % for the large clavicle fixation plate, 0.26 % for the small clavicle fixation plate, 53.38 % for the flexible universal fixation plate, and none for the rigid universal fixation plate. PRINCIPAL CONCLUSIONS: Approximately 27.76 % of the acromion surface curvatures distribution does not overlap with any of our measured fixation plates. Evaluating the acromion surface curvature was possible on plain X-rays in the Y-view only.

• Klíčová slova
• Acromion, Acromion curvature, Acromion fixation, Acromion fractures,
• MeSH
• akromion * diagnostické zobrazování   zranění   anatomie a histologie   chirurgie   MeSH
• fraktury kostí * chirurgie   diagnostické zobrazování   MeSH
• kostní destičky * MeSH
• lidé MeSH
• lopatka * diagnostické zobrazování   anatomie a histologie   MeSH
• radiografie MeSH
• vnitřní fixace fraktury * metody   přístrojové vybavení   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

PURPOSE: Until now, classifications of coracoid fractures have been based on plain radiographs, without use of 3D CT reconstructions. Therefore, the aim of the present study has been to describe the pathoanatomy of these fractures and their associated injuries to the shoulder girdle, on the basis of 3D CT reconstructions. METHODS: The cohort comprised 39 patients, who each sustained a coracoid fracture investigated with 3D CT reconstructions. The patients were assessed in terms of age, gender, pathoanatomy of the coracoid fracture, fractures of other parts of the scapula, and associated injuries to the shoulder girdle. RESULTS: We identified 24 fractures of the base, one fracture of the beak body, eight fractures of the apex, and six comminuted fractures of the coracoid process. A total of 22 associated injuries were found (7 fractures of the acromion, 5 fractures of the anterior glenoid rim, 3 fractures of the superior glenoid, 1 fracture of the inferior glenoid, 4 fractures of the surgical neck, 2 fractures of the scapular body) and 18 other associated injuries to the shoulder girdle (8 AC dislocations, 5 proximal humeral fractures, and 5 clavicular fractures). CONCLUSION: On the basis of 3D CT reconstructions, four basic coracoid fracture patterns were identified. The authors´ findings and literature review have shown that a considerable number of coracoid fractures are combined with injuries to other parts of scapula and shoulder girdle. These associated injuries must be taken into account and targeted when taking the patient's history, and during clinical and primarily radiological examinations.

• Klíčová slova
• Classification, Coracoid process fractures, Pathoanatomy, Scapular fractures,
• MeSH
• akromion MeSH
• fraktury kostí * diagnostické zobrazování   epidemiologie   MeSH
• klíční kost MeSH
• lidé MeSH
• lopatka diagnostické zobrazování   MeSH
• počítačová rentgenová tomografie MeSH
• processus coracoideus * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH