2023 Undergraduate Research Symposium: Carly Ghanem The standard treatment for lower back pain has been interbody fusion: Transforaminal Lumbar Interbody Fusion (TLIF). The invasive nature leads to muscle detachment and damaged nerves. To address these issues, minimally invasive (MI) TLIF techniques have been developed. While MI TLIFs show decreased blood loss and complication rates relative to open TLIF, surgery times and long-term outcomes are reported to be similar. Oblique lateral lumbar interbody fusion (OLLIF) is a MI lumbar spinal fusion through a single 10-15 mm incision, with a faster surgery time and easier approach. Anesthesia, surgery times, and blood loss were recorded for all patients that entered into the EMR. Because no suction is used in OLLIF procedures, blood loss was measured by weighing sponges and subtracting dry weight. To monetize the cost per minute for a hospital, a published reference was utilized and adjusted with the consumer price index. These values were reported in aggregate and stratified, based on spinal level(s) of surgery. Mann-Whitney U-tests were utilized to test the null hypothesis that the OLLIF and TLIF groups have the same or identical mean distributions for age, BMI, blood loss, and uncensored time duration variables. Data analyses were performed using IBM SPSS. A shorter length of stay than TLIF by 58.5% across all surgeries studied was found. The trend of shorter lengths of stay remained consistent when surgeries were stratified based on the spinal level(s) involved. OLLIF also had a lower surgical admission cost than TLIF, with a difference of $6,701 versus $11,583. These findings suggest that OLLIF may be a more cost-effective and efficient alternative to TLIF for treating lower back pain, particularly for hospitals with limited resources.

1. Introduction:
The standard treatment for lower back pain has been
interbody fusion: Transforaminal Lumbar Interbody
Fusion (TLIF). The invasive nature portends significant
morbidity from muscle detachment and denervation. To
address these issues, minimally invasive (MI) TLIF
techniques have been developed. While M}J1IDshow
decreased blood loss and complication rates relative to
open TLIF, surgery times and long-term outcomes are
reported to be similar. Oblique lateral lumbar interbody
fusion (OLLIF) is a MI lumbar spinal fusion through a
single 10-15 mm incision, with a faster surgery time and
easier approach.
Material and Methods:
Anesthesia, surge1ytimes, and blood loss were recorded
for all patients and entered into the EMR. Because no
suction is used in OLLIF procedures, blood loss was
measured by weighing sponges and subtracting d1y
weight. To monetize the cost per minute for a hospital, a
published reference was utilized and adjusted with the
consumer price index. These values were reported in
aggregate and stratified, based on spinal level(s) of
surgery. Mann-Whitney U-tests were utilized to test the
null hypothesis that the OLLIF and TLIF groups have
the same or identical mean distributions for age, BMI,
blood loss, and uncensored time duration variables. Data
analyses were performed using IBM SPSS.
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,..
Results:
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spine
Superior End-Plate of
Inferior Vertebral Body
Overall, across all surgeries studied - length of stay (LOS) for OLLIF
was 58.5% of that seen with TLIF (3.1 vs. 5.3 days). The trend of
shorter LOS for OLLIF remained consistent when surgeries were
stratified and matched for the same number of levels involved (2.6 vs.
4.2 for one, 3.2 vs. 5.8 for two, 3.2 vs. 4.3 for three, and 4.6 vs. 6.7 for
four). Overall, when LOS was converted to inpatient operating costs of
the hospital, the difference in cost of surgical admission was $6,701
OLLIF vs. $11,583 TLIF.
SurgeryTime
■OLLIF IIF
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HospitalStay Costper surgery
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OLLIFvs. TLIF
. Cost reduction
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$ 11,834 per surgery
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Potential Impact on U.S. Healthcare Spending
400,00
lumbar fusions
per year approx.
2022
X $11,834
Cost reduction
per surgery
= $ A,733,600,000
Potential for OLLIF U.S.
health care cost reduction
Conclusion:
The cost reductions and faster recovery times associated with OLLIF make it an appealing alternative to
TLIF. The reduction in resource use suggests that constrained hospitals can achieve greater throughput
efficiency by advocating for OLLIF surgery.