Interbody fusion does not influence development of lumbar compensatory mechanisms 10 year after lumbar fusion — The International Society for the Study of the Lumbar Spine
  1. Schedule
  2. GENERAL POSTER SESSION
  3. Interbody fusion does not influence development of lumbar compensatory mechanisms 10 year after lumbar fusion

Interbody fusion does not influence development of lumbar compensatory mechanisms 10 year after lumbar fusion (#1118)

Kristian Høy 1 , Kamilla Troung 2 , Mads Henriksen 3 , Thomas Andersen 4
  1. Orthopedic Department, Spine section, Aarhus University Hospital, Denmark, Aarhus N, Danmark, Denmark
  2. Department of Neurosurgery, , Aarhus University Hospital, Denmark, Aarhus N, Danmark, Denmark
  3. Department of Radiology, , Aarhus University Hospital, Denmark, Aarhus N, Danmark, Denmark
  4. Department of Orthopedics, , Rigshospitalet University of Copenhagen, , Copenhagen, Denmark

INTRODUCTION: Restoration of lumbar lordosis in lumbar spine surgery is thought to be associated with better postoperative outcomes. Various inter- body fusion techniques can theoretical help to change and correct sagittal balance. Pelvic plays a central role in sagittal balance. The Three key pelvic parameters are pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS). The last 2 can change due to compensatory mechanism. Decrease in SS is posed to increase risk of adjacent segment degeneration (ASD) Aim: To assess radiographic signs of degenerative changes and compensatory mechanisms after lumbar fusion at 10 year follow-up and their relation to outcome comparing posterolateral instrumented fusion (PLF) to Transforaminal interbody lumbar fusion (TLIF) in a RCT
METHODS: 100 pat. enrolled in a RCT between TLIF and PLF had standing lumbar radiographs analyzed with respect to olisthesis, lordotic angle at adjacent level (AL) and differences in SS. SS was determined by PI = PT + SS. Clinical outcome was measured by Owestry disability index (ODI) and SF-36 Physical Function (PF), Bodily pain (BP) and Physical Component Summary(PCS). Data was analyzed using STATA
RESULTS: There was no difference in development of olisthesis at the (AL) between the two groups at 10 year follow-up (p=0.43). Lordotic angle of the adjacent disc decreased with 5 or more degrees in 6 patients in the TLIF group and 3 in the PLF group. Three pats in the TLIF group and 4 in the PLF group had an increase in lordotic angle at the adjacent disc, the remainders were unchanged (p=0.58). Five pat. in the TLIF group and 7 in the PLF groups had a decrease in SS of 5 degrees or more (p=0.51).There was no difference in ODI score nor PF, BS & PCS at 10 year follow-up between those who developed changes in adjacent disc angle and those who remained unchanged (p=0.49, p=0.20, p=0.94 p=0.65). The same held true for changes in SS (p=0.46, p=0.49, p=0.39, p= 0.58)
DISCUSSION: No difference between the two fusion methods with respect to degenerative changes visible on radiographs at 10 years follow-up. Signs suggesting development in compensatory mechanisms (SS) was not associated with poorer clinical outcome

#ISSLS2022