Incidence of Adjacent Segment Disease Requiring Reoperation After Lumbar Laminectomy Without Fusion: A Study of 398 Patients.
BACKGROUND
Adjacent segment disease (ASD) has not been described after laminectomy without fusion.


OBJECTIVE
To determine the incidence of ASD after a 1- or 2-level lumbar laminectomy.


METHODS
We retrospectively reviewed medical records of all patients who underwent 1- or 2-level, bilateral lumbar laminectomy without fusion for degenerative spinal disease (all follow-up ≥1 year). ASD was defined as clinical and/or radiographic evidence of degenerative spinal disease that required reoperation at the level above or below the index laminectomy.


RESULTS
Of the 398 patients, the incidence of ASD requiring reoperation was 10%. The 39 ASD cases were almost equally distributed at L2-L3 (31%), L3-L4 (26%), and L5-S1 (31%), and to a lesser extent at L4-L5 (15%) (P = .51). The ASD incidences of 10% and 9% were equivalent after a 1- and 2-level laminectomy, respectively (P = .76). Rostral ASD was statistically more common than caudal ASD after both the 1- (P < .001) and 2- (P < .001) level laminectomy. Of the 39 ASD cases, 95% required laminectomy, 26% discectomy, and 49% fusion. Average time to ASD was 4 years. After a Kaplan-Meier analysis, time to reoperation for ASD was equivalent among the 1- and 2-level laminectomy cohorts (log-rank test, P = .13).


CONCLUSIONS
The cumulative incidence of ASD requiring reoperation was 10% over a mean of 4 years. Both the 1- and 2-level laminectomy cohorts experienced equivalent incidences and rates of ASD. Of the 39 operations for ASD, about half required a fusion.
‡Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland; §Johns Hopkins Spinal Biomechanics and Surgical Outcomes Laboratory, Baltimore, Maryland.
Mohamad
M
Bydon
Mohamed
M
Macki
Rafael
R
De la Garza-Ramos
Kelly
K
McGovern
Daniel M
DM
Sciubba
Jean-Paul
JP
Wolinsky
Timothy F
TF
Witham
Ziya L
ZL
Gokaslan
Ali
A
Bydon
D000328:Adult; D000368:Aged; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007796:Laminectomy / Q000009:adverse effects*; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D012086:Reoperation; D012189:Retrospective Studies; D024162:Second-Look Surgery / Q000379:methods*; D013122:Spinal Diseases / Q000175:diagnosis* / Q000601:surgery*; D013123:Spinal Fusion