Original Article ISSN (O): 2455-5274; ISSN (P): 2617-5207 A Study of Transverse Diameter of The Lumbar Spinal Canal in Plain Radiograph in Population of Telangana, India Yousuf Begum 1 , Syed Rehan Hafiz Daimib 1 , Syeda Ayesha Fatima 2 , Syeda Khadija Fatima 3 1 Assistant Professor, Department of Anatomy, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, KSA, 2 Assistant Professor, Department of Pharmacology, Apollo Institute of Medical Sciences and Research, Jubilee Hills, Hyderabad, Telangana, India, 3 Assistant Professor, Department of Pathology, Kamineni Institute of Medical Sciences, Nalgonda, Telangana, India. Abstract Background: The present study was conducted to determine Transverse diameter (inter-pedicular distances) of the lumbar spinal canal measured in plain antero-posterior radiograph of 140 subjects (80 males, 60 females) aged between 20 to 60 years in population of Telangana. Subjects and Methods : The present study was conducted in the department of Anatomy, in a teaching medical college and hospital in Hyderabad, Telangana, India. It comprised of antero-posterior plain radiographs of lumbar spine of 140 subjects, aged between 20 to 60 years. Transverse diameter of the lumbar spinal canal or inter-pedicular distances (IPD), and transverse diameter of the vertebral body was measured using electronic Digital Vernier calipers, and the ratio between transverse diameter of vertebral canal and transverse diameter of the corresponding vertebral body were analyzed. Results: Out of 140 patients, males were 80 and females were 60. The mean inter-pedicular distance (IPD) at L1 was 24.2 mm in males and 23.4 mm in females, and at L5 was 30.2 mm in males and 29.6 mm in females. Mean transverse diameter of lumbar vertebral canal (I.P.D) is minimum at L1 vertebra in both sexes. The maximum values of I.P.D were recorded for vertebra L5 for both sexes. The values of IPD are higher in male population in comparison to female counterparts. The mean width of the vertebral body is gradually increasing from L1 to L5. Ratio between transverse diameter of vertebral canal and transverse diameter of the corresponding vertebral body is seen to be constant (0.6) at all lumbar level in both the sexes. Conclusion: Authors found that there is variation in the size of the lumbar vertebral canal between males and females. Even after the revolution of various imaging techniques like CT Scan, MRI, etc., the plain radiography remains the mainstay of investigative procedure particularly in rural setup. Keywords: Inter-pedicular distance, Lumbar vertebral canal, Lumbar spine Corresponding Author: Yousuf Begum, Assistant Professor, Department of Anatomy, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, KSA. E-mail: ybegum@iau.edu.sa Received: 25 September 2020 Revised: 18 November 2020 Accepted: 26 November 2020 Published: 22 December 2020 Introduction Lumbar part of vertebral canal lodges the cauda equina and narrowing of the bony ring of the canal which may be developmental or acquired may lead to compression of these nerve roots and causes low back pain. [1] Huizinga et al, in their studies on lumbar vertebrae obtained from Dutch cadavers, found that in developmental stenosis the interpedicular distance were normal, whereas the mid- sagittal diameters were reduced a fact later confirmed by Larsen. [2] Lumbar canal stenosis is one among the major causative factors producing low back pain. [2] Low back pain is one of the most common health problems affecting up to 85% of people at least once in their lifetime. [3] Stenosis due to decreased sagittal diameter has been reported in the cervical spine as well as in the lumbar spine. [4] Ahmad T et al, in their study of lumbar canal by MRI shows that stenosis of the spinal canal is due to decreased inter-pedicular distance. [5] It has been suggested that reduced interpedicular distance is one of the causes of primary narrowing of the spinal canal. Reports of value of lumbar interpedicular distance of white Americans, black and white South Africans, Nigerians, Spanish subjects and in adult Saudis have shown that the transverse diameter of lumbar spinal canal exhibits ethnic variations. [5,6] According to Christenson PB, Schonstrom NS et al, Hamanashi C et al the measurement of transverse diameter of lumbar canal is an important tool for diagnosis of narrowing of lumbar canal referred to as lumbar spinal stenosis (LSS). [7–9] The study of Amonoo-Kuofi HS, Hinck et al shows that the normal values of transverse diameter of lumbar canal show gender and regional variations and these values have been used to diagnose cases of LSS by morphometric Academia Anatomica International  Volume 6  Issue 2  July-December 2020 81