Postoperative cervical spine specimens studied with the cryoplaning technique

Eight cervical spine specimens from patients who had undergone anterior and/or posterior screwplate fixation for traumatic or pathologic fractures and degenerative disorders were frozen in situ during clinical autopsies after the arteries were injected with red contrast medium. After partial thawing of the specimens, the metallic implants were extracted and the screw tracts and other implant cavities were filled with blue casting medium. Sagittal high-resolution computed tomography (CT) scans of the frozen specimens were obtained and correlated with closely spaced cryosectional images at the same levels. This technique not only facilitates accurate radiologic pathoanatomic correlations, but also detailed analysis of implant positioning, adequacy of reduction and decompression, and the cause of surgical complications.