Attachments of the posterior layer of lumbar fascia

Study Design. Superficial and deep laminae of the posterior layer of lumbar fascia were dissected. The lumbar portion was measured for evidence of seg mental thickenings. Superior attachments were dissected, documented, and ph otographed. Objectives. To verify the existence of posterior accessory ligaments and es tablish the superior attachments and fiber angles of the posterior layer of lumbar fascia. Summary of Background Data. There have been two small dissection studies on the posterior layer. Their findings are conflicting in several areas of cl inical significance. Thickenings in the lumbar region were described in one study, but have not been verified. The superior attachments of the posteri or layer have not been formally documented. Methods. Study 1: In 21 embalmed cadavers, the lumbar region of the posteri or layer was dissected. The lumbar spinous processes and adjacent fascia we re marked. The fascia was removed and examined, and its thickness measured with a manual micrometer. Results were statistically analyzed. Study 2: Sup erior attachments of the posterior layer in 20 cadavers were dissected and photographed. Capacity to transmit tension was estimated and documented pho tographically, and fiber angles measured in situ. Results. Study 1: There was no evidence of macroscopic segmental thickening in the posterior layer. Study 2: The superficial lamina was continuous sup eriorly with the rhomboids, and the deep lamina with the tendons of spleniu s cervicis and capitis. These previously undocumented attachments were of v ariable thickness and fibrosity, and capable of transmitting tension. Conclusions. Both superficial and deep laminae of the posterior layer are m ore extensive superiorly than previously thought. This may have implication s for certain tests used in assessment and management of low back pain such as the slump and "nonorganic" tests. The thickness of the superior attachm ents is variable. Their capacity for load bearing is yet to be quantified.