RESUMO
BACKGROUND:Application of Wiltse paraspinal sacrospinalis splitting approach can reduce paraspinal muscle injuries caused by operations, but there are stil no precise criteria to determine anatomic locations of longissimus-multifidus cleavage planes. OBJECTIVE:To have an intimate knowledge of structural characteristics of Wiltse paraspinal sacrospinalis splitting approach, to determine specific locations of longissimus-multifidus cleavage planes in different lumbar segments, and to provide experiences and references for its clinical applications by observations and measurements of autopsies and magnetic resonance images in Chinese people. METHODS:Ten embalmed adult cadavers were used for anatomical observations. The natural cleavage planes between longissimus and multifidus were noted and bluntly dissected bilateraly. Measurements were done between these planes and the midline at levels of spinous processes of L2 and L4. 400 patients’ images of lumbar spines were also used for observations. Measurements were taken bilateraly between longissimus-multifidus cleavage planes and the midline at levels of discs from L2/L3 to L5/S1. The correlations between these distances and sex or age were analyzed. RESULTS AND CONCLUSION:No important vessels or nerves were found in the longissimus-multifidus cleavage planes of al 10 cadavers. Superior facets and roots of transverse processes could be exposed at the bottom of the planes. At L2, the mean distance was (2.3±0.3) cm; at L4, (3.4±0.6) cm. Of al 400 images, the mean distances from L2/L3 to L5/S1 were respectively (19.71±1.93) mm, (23.49±2.49) mm, (27.49±2.84) mm and (31.36±3.15) mm. No strong correlation was discovered between sex or age with respect to measured distances. This study provides valuable references for clinical application of Wiltse paraspinal sacrospinalis splitting approach. We suggest routine measurements of magnetic resonance imaging before surgeries to reduce iatrogenic injuries.