MORPHOMETRIC STUDY OF THE LUMBAR VERTEBRAL PEDICLE IN MAHARAHTARIAN POPULATION

The pedicle a thick and strongest part of vertebrae is being used for the implantation or fixation of screw (Transpedicular screw fixation) in various spinal problems like fracture of lumbar spine, resection of tumours in vertebral bodies or deformity of vertebral column. However, the success of technique depends on the factors like choice of size of screw for a particular pedicle size and shape. Pedicle screw has its own disadvantage because mismatched size of screw and pedicle instrumentation may fail. For this reason, study of morphometry of pedicles is of special significance as dimensions of pedicle become pivotal information for selection of screw in fixation. In the present study comprehensive morphometric measurements have been taken and an attempt is made to look into all the dimensions of pedicle. Internal and external pedicle diameter measurements give us the exact idea about available thickness of outer cortical and inner cancellous bony part of pedicle. METHODS: The present study Twenty five vertebral columns were procured from the cadavers from Department of Anatomy of Dr. D. Y. Patil Medical College Pimpri, Pune. The cadavers were embalmed and fixed by 10% formalin solution. Normal vertebral columns were included in the study. Gross abnormalities such as scoliosis, kyphosis and pathological vertebrae were excluded. Cadavers were numbered from 1-25 at random. Gender differentiation was not done. Comprehensive dimensions which included pedicle width, pedicle height, internal pedicle height (IPDH) and internal pedicle width (IPDD) diameters were measured using vernier calipers. Statistical mean, standard deviation and range were obtained. Results were tabulated and analyzed. RESULT: In the present study Pedicle height was maximum at L1 (mean 15.2±1.7, range: 12.5 to 18.8) vertebra. Pedicle width increase from L1 (mean 8.2±2.4, range 4.8to16.5) to L5 (mean: 18.4±2.2, range 13 to 22). Internal height gradually increase from L2 to L5 on both sides, and then it increased onL1, on left side. Internal width showed a gradual increase from L1 (mean: 5.4±1.5) to L5 (mean: 8.9±1.9).