Céline Salaud1, Stéphane Ploteau2, Olivier Hamel2, Olivier Armstrong2, Antoine Hamel2. 1. Laboratoire d'Anatomie, Faculté de Médecine de Nantes, 1 rue Gaston Veil, 44035, Nantes, France. celine.salaud@chu-nantes.fr. 2. Laboratoire d'Anatomie, Faculté de Médecine de Nantes, 1 rue Gaston Veil, 44035, Nantes, France.
Abstract
PURPOSE: There are only two descriptions of posterior longitudinal ligament (PLL) at the lumbar spine level but its morphologic characteristics are different to cervical and thoracic levels. METHOD: Spine explantation (from Th12 to L5) followed by resection of the neural arch and the dural sheath in 13 fresh cadavers was performed. The PLL was isolated from other epidural structures and its width was measured and compared to the vertebral body width at each vertebral levels. It was conducted at a microanatomic study concerning the PLL and the posterior outer annulus fibrosus. RESULTS: The PLL width was reduced craniocaudaly significantly, becoming thin from L4. The average width of PLL was 7.8 mm at L1 and 1.9 mm at L5. The width decreased gradually from L1 to L5 or abruptly from L4. The ratio of PLL width compared to the vertebral body width was 21% at L1 and 3% at L5. Microanatomic study confirmed that the PLL is less thick at its annulus fibrosus adhesion at L4-L5 and L5-S1. The relationship between the PLL and other epidural structures are discussed. CONCLUSIONS: The presence and function of the ilio-lumbar ligaments and the articular process orientation of L5-S1 may be explanations for PLL width decrease at L4-L5 and L5-S1. Furthermore, this aspect may be considered as one factor contributing to the occurrence of disc herniations at these levels, which levels are more frequently involved in this pathology.
PURPOSE: There are only two descriptions of posterior longitudinal ligament (PLL) at the lumbar spine level but its morphologic characteristics are different to cervical and thoracic levels. METHOD: Spine explantation (from Th12 to L5) followed by resection of the neural arch and the dural sheath in 13 fresh cadavers was performed. The PLL was isolated from other epidural structures and its width was measured and compared to the vertebral body width at each vertebral levels. It was conducted at a microanatomic study concerning the PLL and the posterior outer annulus fibrosus. RESULTS: The PLL width was reduced craniocaudaly significantly, becoming thin from L4. The average width of PLL was 7.8 mm at L1 and 1.9 mm at L5. The width decreased gradually from L1 to L5 or abruptly from L4. The ratio of PLL width compared to the vertebral body width was 21% at L1 and 3% at L5. Microanatomic study confirmed that the PLL is less thick at its annulus fibrosus adhesion at L4-L5 and L5-S1. The relationship between the PLL and other epidural structures are discussed. CONCLUSIONS: The presence and function of the ilio-lumbar ligaments and the articular process orientation of L5-S1 may be explanations for PLL width decrease at L4-L5 and L5-S1. Furthermore, this aspect may be considered as one factor contributing to the occurrence of disc herniations at these levels, which levels are more frequently involved in this pathology.
Authors: R Shane Tubbs; Marios Loukas; April Phantana-Angkool; Mohammadali M Shoja; Mohammad R Ardalan; Ghaffar Shokouhi; W Jerry Oakes Journal: Surg Radiol Anat Date: 2007-10-20 Impact factor: 1.246
Authors: Murray Echt; Ryan Holland; Wenzhu Mowrey; Phillip Cezayirli; Rafael De la Garza Ramos; Mousa Hamad; Yaroslav Gelfand; Michael Longo; Merritt D Kinon; Vijay Yanamadala; Saad Chaudhary; Samuel K Cho; Reza Yassari Journal: Global Spine J Date: 2020-08-03