Lumbar Sympathetic Chain Tract and Mobility of Oblique Lumbar Interbody Fusion Approach: A Cadaveric Study

Objective: We sought to assess the lumbar sympathetic chain (LSC) relation to the surgical corridor for the oblique lumbar approach and the ability to mobilize the LSC.

Methods: Forty-three cadavers were included. A left-sided anterior retroperitoneal approach was performed in supine position. The distances between the great vessels and psoas muscle (oblique corridor) and distance between great vessels and LSC at the L2/3, L3/4, and L4/5 disk levels were measured. Mobilization of LSC at each disk level was done either close to or away from the psoas muscle, and each mobilization distance was measured.

Results: The presence rates of LSC in oblique corridor were 19.5%, 43%, and 75.7% at L2/3, L3/4, and L4/5 levels, respectively. At the L2/3 disk level, the mean distance between the psoas muscle and LSC and its mobility were 0.61 mm ± 1.31 mm and 2.72 mm ± 1.24 mm, respectively. At the L3/4 disk level, the mean distance between the psoas muscle and LSC and its mobility were 1.72 mm ± 2.53 mm and 3.11 mm ± 1.02 mm, respectively. At the L4/5 disk level, the mean distance between the psoas muscle and LSC and its mobility were 2.94 mm ± 3.52 mm and 2.53 mm ± 1.03 mm, respectively. The mean width of corridor of L2/3, L3/4, and L4/5 were 10.73 mm ± 5.82 mm, 12.63 mm ± 5.02 mm, and 15.43 mm ± 6.31 mm, respectively.

Conclusions: The LSC tract usually lies in the oblique corridor in L4/5 but keeps decreasing in prevalence when approaching L3/4 and L2/3 levels. It can be mobilized a few millimeters close to or away from the psoas muscle. Care should be taken to prevent an LSC injury, particularly when the LSC needs to be retracted along with the psoas muscle.