Cervicothoracic Pedicle Morphometry: Using an Osteological Collection to Characterize Trends in Pedicle Size

Pedicle screws are a common treatment option for spinal instability. Despite their popularity, pedicle screws carry the risk of transpedicular violation with subsequent neural and vascular damage. This study measured the pedicle dimensions of 500 dry specimens in an osteological collection. The data provide the orthopedic spine surgeon with an accurate measure of pedicle morphometry in light of previously limited and contradictory results. The study demonstrates that pedicle height at the cervicothoracic junction tends to increase with body height, particularly for females. Additionally, T1 pedicle width is smaller for females than males and, for males, tends to decrease with increasing body weight. These results are valuable to the spine surgeon because they suggest that taller patients may afford a larger margin for error in the vertical plane. However, they also demonstrate that heavier patients do not have wider pedicles and thus cannot be assumed to tolerate or require larger-diameter screws. (Journal of Surgical Orthopaedic Advances 27(1):33–38, 2018)
Key words: cervical pedicle, femoral head, fusion, instrumentation, morphometry, pedicle dimensions, pedicle height, pedicle screw, pedicle size, pedicle width, screw fixation, thoracic pedicle