Abstract:
Objective
To determine the incidence and the risk factors of adjacent segment degeneration£¨ASD£©after
L4-5 fusion with posterior lumbar interbody fusion £¨PLIF£©or transforaminal lumbar interbody fusion £¨TLIF£©.
Methods
Results
Of the 355 patients who underwent spinal fusion at the L4-5 level, the ASD occurred in 42 patients£¨54 segments£©£¬including 3 patients at L1-2 £¨5%£©, 13 at L2-3 £¨24%£©, 29 at L3-4 £¨54%£©and 9 at L5S1 £¨17%£©, associated with a total incidence of 11.8%. In term of involved segment, the L3¡¢4 was the most susceptible level£¨P<0.001£©. Although The incidences of ASD in the PLIF was higher than the TLIF, there was not statistical difference between them £¨14% versus 9.5%, P=0.189£©. The cephalic ASD was statistically more common than the caudal ASD in both the PLIF £¨P<0.001£©and TLIF£¨P<0.001£©. The average elapsed time to ASD was 2 years after L4-5 fusion, however, no a statistical difference was noted between the PLIF and TLIF in time of ASD happened based on a Kaplan-Meier analysis £¨P=0.1559£©.
Conclusions
The cumulative incidence of ASD requiring reoperation is 12% over a mean period of 2 years with the most susceptible level at the L3-4. Both the PLIF and TLIF have similar incidences of ASD.