Radiologic stability analysis of adjacent segments after different fusion segments of posterior lumbar interbody fusion

LIU Yu-zeng; HAI Yong; YANG Jin-cai; GUAN Li

doi:10.3969/j.issn.2095-252X.2013.10.005

Abstract：Objective To investigate the radiologic stability of adjacent segments after single, double and triple fusion segments of posterior lumbar interbody fusion ( PLIF ). Methods All 45 patients who were treated by PLIF were divided into 3 groups, including group A of single segment, group B of double segments and group C of triple segments, with 15 patients in each group. The effects on the stability of adjacent segments after fusion were retrospectively analyzed. The preoperative and postoperative lumbar lordosis angle and range of motion ( ROM ) of upper adjacent segments were measured. Results The results showed the lumbar ROM was decreased in the latest follow-up when compared with that preoperatively by 10.4° in group A, 11.4° in group B and 16° in group C on average. And the ROM of adjacent segments was increased in the latest follow-up when compared that preoperatively by 2.1° in group A, 1.9° in group B and 8.1° in group C on average. The preoperative ROM of adjacent segments was ( 3.6±2.0 ) °, ( 8.4±5.5 ) ° and ( 5.0±4.5 ) ° in group A, group B and group C, and the postoperative ROM was ( 6.5±1.6 ) °, ( 9.8±9.5 ) ° and ( 13.0±7.6 ) ° respectively. The differences between the preoperative and postoperative ROM in each group were statistically signiifcant ( P<0.01 ), and the differences of the postoperative ROM among all groups were statistically signiifcant ( P<0.01 ). Conclusions With the adding of fusion segments, the ROM of adjacent segments also increases. Based on the preoperative lumbar lordosis angle, a modest recovery of the physiological lordosis angle is achieved during the operation. It is an effective method to maintain the stability of adjacent segments.