Outcome of Two Fusion Methods In Isthmic and Degenerative Spondylolisthesis of the Lumbar Spine

Abstract

‐ Abstract ‐ Design : A retrospective study was performed in isthmic and degenerative spondylolisthesis patients who had undergone posterolateral fusion (PLF) only (group Ⅰ) or posterolateral fusion (PLF) with posterior lumbar interbody fusion (PLIF) (group Ⅱ). Objectives : The objective of this study was to help in the selection of a surgical treatment option for spondylolisthesis. Summary of Literature Review : Irrespective of whether groupⅠ or groupⅡ, satisfactory results have been reported in the surgical treatment of spondylolisthesis. However, isthmic and degenerative types have not been investigated in terms of outcome. Material and Methods : We analyzed 112 patients (Isthmic: groupⅠ(32), groupⅡ(22), Degenerative : groupⅠ(37), groupⅡ(21)) who underwent surgical treatment for spondylolisthesis between April 1995 and December 2000. Kirkaldy-Willis criteria, radiologic union state, reduction ratio of slippage, change of disc space and change of segmental angle were analyzed as indicators of outcome. Results : We found the following by radiologic analysis: In isthmic spondylolisthesis, groupⅡ was better than groupⅠ in terms of reduction ratio of slippage (reduction loss:3.38% vs. 2.3%, P=0.15), change of segmental angle (reduction loss : 2.11 ° vs. 1.6° , P=0.15), bone union (83% vs. 92%, P=0.45) and change of disc space (reduction loss : 2.83 mm vs. 1.9 mm, P=0.02). In the degenerative spondylolisthesis, groupⅡ did not show significant difference from groupⅠ in terms of reduced slippage (reduction loss: 3.8% vs. 3.85%, P=0.47), change of segmental angle (reduction loss: 2.73。vs. 2.64。 , P=0.43), bone union (80% vs. 87%, P=0.72) or disc height (reduction loss: 3.2 mm vs. 3.14 mm, P=0.45). In terms of clinical outcome, groupⅡ was better than groupsⅠ in cases of isthmic spondylolisthesis (fair≤:85% vs. 93%, P=0.72), however, groupsⅡ was not better than groupsⅠ in cases of degenerative spondylolisthesis (fair≤:83% vs. 85%, P=0.23). Conclusions : In the degenerative spondylolisthesis patient, no significant difference was found between groupⅠ and groupⅡ, but in the isthmic spondylolisthesis patient, groupⅠ and groupⅡ were found to be significantly different in terms of the reduction ratio of the disc heights.