腰椎不安定椎に対するＰｏｓｔｅｒｏ‐Ｌａｔｅｒａｌ Ｓｐｉｎａｌ Ｆｕｓｉｏｎについて 特にその制動効果について

Abstract

In this paper, effect of P-L fusion was studied on the fixed intervertebral space and other lumbar intervertebral spaces in 20 patients who had gotten good union at L4/5 level. We regard P-L fusion as not a fixed operation but a breakage operation. With regard to radiological approach, we applied Pierre's method to measure the angle of displacement, horizontal displacement and disc space height. Evenly increase of motion angle was recognized at L2/3, L3/4 and L5/S1 levels respectively. At fixed intervertebral space, motion angle remained a little. Therefore, P-L fusion is not a completely fixed operative method but gives a small range of motion, which is very beneficial for other intervertebral spaces. Namely “breakage effect” protects other intervertebral spaces from new instability.