Purpose

Adjacent segment disease (ASD) in the lumbar spine is a well-known sequela of lumbar fusion surgery. The annual incidence of adjacent level re-operation is approximately 3% with a ten-year prevalence of 20-30%. Frequently, the surgical treatment involves decompression of the adjacent level coupled with extension of the instrumentation and fusion. Advocates of this paradigm cite the altered kinematics and biomechanics of levels adjacent to a lumbar fusion mass. Furthermore, decompressed levels adjacent to a fused segments are associated with higher rates of ASD in retrospective studies. Yet, a retrospective review of higher quality data concluded decompression adjacent to single-level fusion provides similar outcomes compared to fusions extending across the decompressed segments. Given the conflicting data currently available, higher quality data are needed to guide surgical decision-making in ASD. The purpose of this trial is to prospectively compare decompression and decompression with fusion in patients with lumbar ASD.

Condition

Eligibility

Eligible Ages
Over 18 Years
Eligible Genders
All
Accepts Healthy Volunteers
Yes

Inclusion Criteria

  • Adult patients at least one year removed from a previous instrumented posterior lumbar fusion - Patients with any prior posterior fusion involving L2 to the sacrum, whether single-level or multilevel - Patients with symptoms related to central and lateral recess at the supradjacent level that have persisted despite at least six weeks of non-operative therapy modalities

Exclusion Criteria

  • Patients with previous uninstrumented lumbar fusions - Patients with traumatic, neoplastic, or infectious etiologies at the adjacent segment - Patients with prior iliac or sacroiliac fixation and those with nonunion as the primary indication for surgery - Patients with pre-existing instability at the supradjacent level. The definition of instability will be determined based on standing lateral, flexion and extension plain radiographs. Patients with >3mm of change between these views will be excluded. - Retrolisthesis will not be a criterion for exclusion

Study Design

Phase
Study Type
Observational
Observational Model
Cohort
Time Perspective
Prospective

Arm Groups

ArmDescriptionAssigned Intervention
Observational: Decompression Eligible patients may have a preference for the surgical procedure they wish to have. In these instances, they may choose to undergo a decompression alone or a decompression with extension of fusion. These patients are eligible for the study and will be enrolled under observational arms. This arm refers to the decompression alone observational study arm.
  • Procedure: Observational: Decompression
    Patients will undergo decompression alone of the supradjacent level. The surgical technique will be surgeon dependent. All surgeons will be encouraged to avoid damaging facet joints above the fusion mass, retaining 50% of the pars of the decompressed level and performing as minimal of a medial facetectomy as necessary.
Observational: Extension Fusion Eligible patients may have a preference for the surgical procedure they wish to have. In these instances, they may choose to undergo a decompression alone or a decompression with extension of fusion. These patients are eligible for the study and will be enrolled under observational arms. This arm refers to the decompression with extension of fusion observational study arm.
  • Procedure: Observational: Extension Fusion
    Patients will undergo decompression and extension of posterior instrumentation and fusion. This may or may not include exchange of pre-existing instrumentation. The use of interbody cages will be left to the discretion of the treating surgeon. The purpose of introducing this heterogeneity is to increase the generalizability of the trial results. The fusion cohort will not utilize bone morphogenetic protein products.

Recruiting Locations

Massachusetts General Hospital
Boston, Massachusetts 02114
Contact:
Daniel Tobert, MD

More Details

Status
Recruiting
Sponsor
Massachusetts General Hospital

Study Contact

Daniel Tobert, MD
617-643-3932
DTOBERT@mgb.org

Notice

Study information shown on this site is derived from ClinicalTrials.gov (a public registry operated by the National Institutes of Health). The listing of studies provided is not certain to be all studies for which you might be eligible. Furthermore, study eligibility requirements can be difficult to understand and may change over time, so it is wise to speak with your medical care provider and individual research study teams when making decisions related to participation.