Variation of conus medullaris location based on magnetic resonance imaging of the lumbar spine in Indonesia: A study at Dr Soetomo General Academic Hospital, Surabaya, Indonesia

Introduction: Recognition of conus medullaris position, contains lumbosacral plexuses which supply motor and sensory innervation to the whole lower limb, pelvic and perineal areas, is critical to avoid injury due to lumbar procedures, such as spinal anesthesia and lumbar punctures. This study aimed to investigate the position of conus medullaris among Indonesians through magnetic resonance imaging (MRI) of the lumbar spine at Dr. Soetomo General Academic Hospital in order to minimize the risk of conus medullaris trauma. Methods: A retrospective study was conducted to investigate the conus medullaris level and its correlation to gender and age Indonesian patients. The data were collected from lumbar MRI at Dr Soetomo General Academic Hospital during January 2020 and December 2021. The level variations of conus medullaris were recorded and determined as the highest, lowest and most common location descriptively. Results: A total of 257 patients (126 male and 131 female) were included. The highest level of conus medullaris was in T11-T12 vertebrae (five patients). There were 12 patients in T12 vertebrae, T12–L1 in 86 patients, L1 in 62 patients, L1–L2 in 76 patients, and L2 in 12 patients. The lowest level was in between L2 and L3 vertebrae in 4 patients. Gender and age had no association with conus medullaris level. Conclusion: The lowest level of conus medullaris was in between L2 and L3 vertebrae. The lumbar procedure such as punctures should be done below the L3 to avoid conus medullaris puncture trauma.