Cobb angle measurements on lateral lumbar radiographs obtained in the lateral recumbent position: A Ghanaian study

Background: Lumbar lordosis and its quantification are important for clinical consideration. The Cobb method is one of the important radiographic methods for estimating lumbar lordosis. Supine lateral lumbar radiographs remain the gold standard for accurate measurement of lumbar lordosis. This study aimed at measuring the average lumbar lordosis of Ghanaian patients using the Cobb method. Methods Using a goniometer, Cobb angle measurements were manually made on lumbar spine radiographs with no spinal deformities obtained from three study sites from April 2021 to June 2021. Subgroup analyses of lumbar lordotic angles (LLAs) were also conducted. Results The average LLAs obtained from the radiographs of the 118 patients were 27.18 o (SD = 13.05 o ) for the L1-L5 and 43.56 o (SD = 14.58 o ) for the L1-S1. The LLAs for females [L1-L5: 29.85 o (SD = 11.59 o ), L1-S1: 47.076 o (SD = 13.354 o ) were higher than males: L1-L5:24.32 o (SD = 13.98 o ); L1-S1: 39.81 o (SD = 15.05 o ). Younger patients had higher LLAs. There was a strong positive correlation between L1-S1 and L1-L5 values ( R  = 0.825) in the Ghanaian populace. The LLAs generally decreased with aging. Finally, LLAs are gender dimorphic among Ghanaians with higher values reported in females. Conclusion This study revealed the existence of an association between age and angle of lumbar lordosis and gender dimorphism in Ghanaian patients. Disc herniation occurs at higher levels of the spine as age increases and lumbar lordotic Cobb’s angle decreases. The LLA and age can therefore be assumed as predictors of the level of lumbar disc herniation.