A Clinical Analysis of Degenerative Supondylolisthesis

ABSTRACT

The auther has studied 60 patients of degenerative spondylolisthesis diagnosed and operatively treated at Hanyang University Hospital from January 1987 to June 1992, and analized the outcome. The results were summarized as followings 1) Male to female ratio was 14, showing female predominance. Average peak ages were 5th and 6th decades. 2) "Pedicle-Facet Angle" and the degree of slipping had directly proportional relationship(Y=0.58X+110). The wider the angle is, the more slipping develops. 3) The significant symptom and sign were neurogenic intermittent claudication and negative straight-leg-raising test. 4) The degenerative spondylolisthesis developed most frequently at L4-5 level(74%), L5-S1(15%), L3-4(8%), 57 cases(95%) fell into Grade by Meyerding classification. 5) Complete or incomplete block on myelogram was present in 59%, and pseudodisc and lumbar spinal stenosis were noticed on CT. 6) Laminectomy with P.L.I.F. were done in 50 cases(83%) and total laminectomy and medial facetectomy and foraminotomy were done in only 4 cases(7%). In the comparision on the slipping degree before & after operation, in 55 cases(92%), slipping degrees showed no great change less than 2mm, but the almost showed exellent & good results. So we considered decom pression & fusion without excessive reduction was sufficient. 7) Threaded fusion cage(T.F.C) had the several benefits that 1) stability was good, 2) osteosynthesis through threaded was possible and 3) postoperative ambulation was possible earlier. Therefore recently, P.L.I.F. using T.F.C in the treatment of degenerative spondylolisthesis were used in many cases and further evaluation for T.F.C. should be considered.