A modified method to treat severe asymptomatic pre‐existing degeneration of adjacent segment: a retrospective case‐control study

Abstract Background Pre-existing degeneration of adjacent segment is an important risk factor for adjacent-segment (ASD), but only limited and controversial studies have addressed its management. Methods We retrospectively analyzed patients with symptomatic the L5/S1 warranting surgical interference severe asymptomatic L4/5 segment. Of these patients, those who underwent interbody fusion causative (L5/S1) distraction intervertebral space facet were included in Group A (n = 103), while both segments B 81). Clinical radiographic outcomes evaluated. Results Mean follow-up time was 58.5 months (range, 48–75 months). found no significant difference clinical or incidence ASD L3/4 between Groups B. Compared B, experienced less bleeding (315 ± 84 ml vs. 532 105 ml), shorter operation (107 34 min 158 55 min) lower costs (US $13,830 $2640 US $16,020 $3380; P < 0.05). In A, disc height ratio (DHR) significantly increased from a preoperative value 0.40 0.13 to last–follow-up 0.53 0.18 ( 0.05), degree canal stenosis (DCS) decreased 34.3 11.2% 15.9 9.3 % Conclusions This modified method could be effective treating pre-existing lumbar spine.