Patients who underwent posterior lumbar fusion for spondylolisthesis with stenosis with spinous process fixation compared with pedicle screws had reduced operative times and hospital stays and improved outcome scores, according to a study presented at the Congress of Neurological Surgeons Annual Meeting.
In a prospective, non-randomized study, Robert L. Tatsumi, MD, of the Northwest Spine Research Foundation in Tualatin, Ore., studied 59 patients who underwent either posterior lumbar fusion with pedicle screws or the spinous process fixation system (ASPEN system, Lanx). All patients had symptomatic degenerative spondylolisthesis with stenosis and an average age of 71 years. Oswestry Disability Index (ODI) and SF-36 values were collected preoperatively and up to 2 years postoperatively.
Tatsumi found hospital stays of 28 hours for patients in the spinous process fixation group compared to 66 hours for patients in the pedicle screw group. ODI scores increased 26 points when using the spinous process fixation system, compared to 13 points for patients in the pedicle screw group, according to the abstract.
The spinous process group also significantly differed from the pedicle screw group for operating room time (113.28 minutes vs. 232.67 minutes).
The spinous process group had lower hardware/biologic costs ($11,449 vs. $13,546) and hospital costs ($30,415 vs. $45,458) when compared with the pedicle screw group, however, there was no significant difference in the insurance payments. The hospitals collected a higher percentage of their charges with the spinous process group vs. the pedicle screw group (75.6% vs. 55.1%).
The researcher found no statistical difference among age groups, with older patients experiencing similar postoperative improvement to younger patients.
"These findings help confirm the positive patient experiences we have been seeing in our practice, and support the use of the ASPEN device as preferred instrumentation for many patients, such as the elderly, who may not be able to tolerate traditional procedures,” Tatsumi stated in a Lanx press release.
Tatsumi, RL. Posters #1227 and #1388. Presented at the 2012 Congress of Neurological Surgeons Annual Meeting; Oct 6-10; Chicago.
Disclosure: Tatsumi is a clinical research and education consultant for Lanx Inc.