Applied anatomical study of the compression of posterior ramus of lumbar nerve

Objective:To explore the primary factor of the compression of posterior ramus of lumbar nerve.Methods:The relationship of the position between posterior ramus of lumbar nerve and bone fibrous foramen,the diameter of the canal and its location were observed on 20 adult cadavers.Results:The longitudinal and transverse diameters of the foramen L\-3 were 5.6±0.9mm and 3.4±0.5mm,L\-5 3.5±0.3mm and 2.1±0.2mm respectively.The intertransverse ligament of L\-\{4-5\} was 1.5±0.7mm and 2.0±0.8mm in thickness.The location was 30～40mm on both sides of the middle line of corresponding lumbar vertebra.Conclusion:The characteristics of the structure of bone fibrous foramen are the morphological basis for compression of posterior ramus of lumbar nerve and provide the anatomical basis for clinical treatment of lumbar back pains.