A STUDY OF PEDICLE MORPHOLOGY OF LOWER THORACIC AND LUMBAR VERTEBRA

Abstract

Siddhartha Avuthu 1 , Parameswara Rao Gompa 2

BACKGROUND Anatomy of pedicle has gained importance because of accelerated use of pedicle fixation devices. The detail of pedicle morphometry becomes important as it helps in the selection of most suited pedicle screw. METHODS Computed tomography scans of lower thoracic and lumbar vertebrae (T9-L5) were reviewed. Using the bone window, the transverse section on which the left and right pedicle appeared largest is selected. Transverse pedicle width, Transverse pedicle angle, Chord length/Screw path length were measured. RESULTS Widest pedicle was seen at L5 with a mean of 12.74 mm. The narrowest was seen at T9 with a mean of 5.81 mm. The shortest distance is seen at T11 with a mean of 31.59 mm. The longest distance is seen at L5 with a mean of 40.12 mm. The largest angle is seen at L5 with a mean angle of 20.4o . The shallowest was at T12 with a mean of -0.160 . CONCLUSION Differences exist between the pedicles within same population. Preoperative CT-based pedicle dimensions should be recorded if possible for preoperative planning of pedicle implant placement and sizes to avoid inadvertent complications.

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