Can the Interspinous Device, SPIRETM, be an Alternative Fixation Modality in Posterior Lumbar Fusion Instead of Pedicle Screw?
OBJECTIVE
Although conventional posterior lumbar interbody fusion (PLIF) using pedicle screws provides successful outcomes, pedicle screw related complications are sometimes noted. SPIRE? was invented as an interspinous fixation device (ISD) to replace pedicle screw. The aim of this study is to evaluate the clinical and radiological outcomes in patients who underwent unilateral PLIF using SPIRE? compared with a pedicle screw.


METHODS
All consecutive patients who show medically intractable lumbar degenerative disease with unilateral radiculopathy and mild instability were enrolled. Thirteen patients who underwent the PLIF using SPIRE? (ISD group), and age, gender, and index level matched patients who underwent the PLIF using pedicle screw (PS group) were recruited in a 1:1 ratio. Pain, Oswestry Disability Index (ODI), disc height, and slippage were evaluated.


RESULTS
Both PS and ISD groups revealed significant improvement and there was no significant difference between them (back pain, p=0.18; leg pain, p=0.51; ODI, p=0.82). Although the ISD group showed spondylolisthesis for the first 3 months after the surgery, there was no significant difference compared with the PS group (p=0.65). Disc height decreased in both the ISD group (10.8 mm?7.7 mm) and the PS group (12.8 mm?10.8 mm), and this difference had statistical significance (p < 0.01). In aspect of perioperative outcomes, the ISD group displayed better outcomes than the PS group (blood loss, p < 0.001; surgery time, p=0.017).


CONCLUSIONS
SPIRE? fixation for PLIF demonstrates comparable clinical outcomes with pedicle screw. It may provide weak fixation but it is acceptable. This technique may be an alternative for the patients with unilateral radiculopathy and mild instability.
Seoul National University Bundang Hospital, Seoul National University College of Medicine, Spine Center, Department of Neurosurgery, Seongnam, Gyeonggi, Republic of Korea.
Chang-Hyun
CH
Lee
Seung-Jae
SJ
Hyun
Ki-Jeong
KJ
Kim
Tae-Ahn
TA
Jahng
Hyun-Jib
HJ
Kim
D000368:Aged; D005260:Female; D006801:Humans; D016268:Internal Fixators; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D065289:Pedicle Screws; D011843:Radiculopathy / Q000000981:diagnostic imaging* / Q000601:surgery*; D012189:Retrospective Studies; D013123:Spinal Fusion / Q000295:instrumentation* / Q000379:methods