Title: DETERMINATION OF TRANSPEDICULAR SCREW PARAMETERS WITH THE HELP OF PEDICLE MORPHOMETRY OF THORACIC VERTEBRAE FOR SAFE TRANSPEDICULAR SCREW FIXATION - A CADAVERIC STUDY
Abstract:CONTEXT (BACKGROUND):It is very essential for a surgeon to have the knowledge of pedicle parameters for stabilizing the thoracic vertebra by Transpedicular screw fixation.AIM: To measure the anterior ...CONTEXT (BACKGROUND):It is very essential for a surgeon to have the knowledge of pedicle parameters for stabilizing the thoracic vertebra by Transpedicular screw fixation.AIM: To measure the anterior pedicle diameter, posterior pedicle diameter, pedicle diameter at isthmus (minimum pedicle diameter), sagittal pedicle diameter, pedicle length and chord length of all twelve thoracic vertebrae in south Indian population and to determine the length and diameter of the screw for accurate and hazardless surgery.SETTINGS AND DESIGN: A cadaveric study was done in a medical institution.METHODS AND MATERIALS: Study was done on 20 cadaveric specimens of thoracic region of vertebral column.All the thoracic vertebrae (T1-T12) were separated in all 20 specimens, and in total 480 pedicles were studied for anterior pedicle diameter, posterior pedicle diameter, pedicle diameter at isthmus, sagittal pedicle diameter, pedicle length, and chord length and with the help of these statistics the diameter and length of the screw were determined.STATISTICAL ANALYSIS USED: Simple analysis was used.RESULTS: Pedicle diameter at isthmus (minimum diameter) at T1 is 6.98±1.15,which decreases caudally to minimum at T4 (3.90±0.80)then gradually increases caudally to a maximum at T12 (7.88±1.38).Anterior pedicle diameter at T1 is 7.56±1.09which decreases caudally to minimum value at T5 (5.28±0.92),and again increases caudally reaching maximum value at T12 (9.04±1.63).Posterior pedicle diameter at T1 is (7.74±1.34)which decreases caudally to minimum at T4 (4.70±1.00),and increases caudally to a maximum value at T12 (8.51±1.20).Sagittal diameter at isthmus is gradually increasing from minimum at T1 (8.47±0.87) to maximum at T12 (15.40±2.20).The Chord length is minimum at T1 (31.88±2.67)and gradually increases caudally to a maximum at T12 (45.57±3.86).The Pedicle length is minimum at T1 (4.84±0.85)and increases caudally to a maximum at T8 (6.14±0.99)and again decreases caudally and at T12 Pedicle length is (5.15±0.64).CONCLUSIONS: Spinal surgeons, neurosurgeons or orthopaedic surgeons should have the essential knowledge of pedicle diameter and chord length for selecting the appropriate Transpedicular screw.Read More