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PURPOSE: To compare digital X-ray, CT, and MRI in the evaluation of ligamentous and osseous lesions in upper cervical spine specimens after artificial craniocervical injury with the findings of macroscopic preparation. MATERIALS AND METHODS: A rotation trauma of defined severity was applied to 19 human corpses. After dissection of the neck specimens, digital X-ray (DIMA Soft P41, Feinfocus), conventional and helical CT (CTi, High Speed, GE, collimation 1 mm; pitch 1.0), and MRI were performed from the skull base to C3. The findings were correlated with the macroscopic results of preparation. MR (Magnetom Vision, Siemens) imaging was obtained with a 1.5 T system using 2D- and 3D-sequences. RESULTS: Preparation revealed 6 fractures of the vertebral bodies, 5 fractures of the dens axis, 1 fracture of the arcus anterior of the atlas, 4 osseous flakes at the occipital condylus, and 6 lesions of the alar ligaments. Digital radiography showed all fractures and 4 osseous flakes at the occipital condylus. With conventional and helical CT, all fractures and all ruptured alar ligaments could be detected. 2D MRI depicted 9 of the fractures and 3D MRI showed fractures. With 2D MRI, 2 of the 4 osseous flakes at the condylus could be detected and with 3D MRI one occipital condylus fracture could be depicted. Ligamentous injuries were visualized by 2D MRI in 2 of 6 cases and by 3D MRI in one case. CONCLUSIONS: In post-mortem studies, CT was superior to MRI in the visualization of osseous and ligamentous injuries after trauma of the upper cervical spine. However, these results are not transferable to patients with rotation injury in general.

Rotation of the radius about the fixed ulna is analysed radiographically in an anatomic specimen. While rotating the styloid process of the radius migrates in relation to the ulna. Compared to the prone position supination leads to a more distal position of the styloid process.

The palmar plates of the PIP of the fingers are examined in 43 hands. Apart from macroscopic morphometric studies special attention is paid to the density of bone in the areas of insertion, measured with the help of a computerized image analysing system. Especially the distal area of insertion in the basis of the medial phalanx shows a low density of bone. The consequent low adaptation to stress explains clinical findings, describing most frequent osseous ruptures of the palmar plates in case of hyperextension injuries to the fingers. The fibrous structure of the palmar plate is studied in histological sections. A palmar layer of transversally running collagenous fibres, as well as a medial layer of diagonally and a dorsal layer of longitudinally running fibres can be differentiated. The distal area of the palmar plate mostly consists of transversal, the proximal area of longitudinal collagenous fibres. Therefore a hyperextension stress, hitting the fibres in a right angle distally, cannot be neutralized sufficiently. This result is closely linked to clinical observations describing mostly distal ruptures of the palmar plate in spite of its proximal region being of weaker structure.