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. 2016 Jun;13(2):57-62.
doi: 10.14245/kjs.2016.13.2.57. Epub 2016 Jun 30.

Clinical and Radiological Comparison of Semirigid (WavefleX) and Rigid System for the Lumbar Spine

Do-Keun Kim  1 , Hyunkeun Lim  2 , Dae Cheol Rim  3 , Chang Hyun Oh  4
Affiliations

Clinical and Radiological Comparison of Semirigid (WavefleX) and Rigid System for the Lumbar Spine

Do-Keun Kim et al. Korean J Spine. 2016 Jun.

Abstract

Objective: Spinal fusion operation is an effective treatment in the spinal pathology, but it could change the physiological distribution of load at the instrumented and adjacent segments. This retrospective study compared the radiological and clinical outcomes of patients undergoing lumbar fusion with semirigid rods versus rigid rods system.

Methods: Using transpedicular fixation and posterior lumbar interbody fusion at the level of L4/L5, 20 patients were treated with semirigid rods (WavefleX, SR group), and 20 patients with rigid rods (titanium, RR group). Clinical and radiological outcomes were evaluated, including visual analog score for lower back pain and leg pain, Prolo functional and economic scores, statues of implanted instruments, fusion rate, and complications during 24-month follow-up.

Results: Clinical scores were significantly improved until postoperative 24-month follow-up as compared with preoperative scores in both groups (p<0.05), with similar levels of improvement observed at the same time points postoperatively between the 2 groups. Prolo economic scores were significantly improved in SR group compared to RR until 12 months, but this improvement became similar after 18 months. The overall fusion rate was 94.1% until the 24-month follow-up for both groups. No significant complication was observed in both groups.

Conclusion: The results of the present study indicate that semirigid rods system with posterior lumbar interbody fusion showed similar clinical and radiological result with rigid rods system until 2 years after instrumentation. The WavefleX rods system, as a semirigid rods with unique characteristics, may be an effective alternative treatment for patients in lumbar fusion.

Keywords: Fusion; Outcome; Semirigid instruments; Spinal fusion; WavefleX.

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Conflict of interest statement

CONFLICT OF INTEREST: No potential conflict of interest relevant to this article was reported.

Figures

Fig. 1
Fig. 1. Image of WavefleX rods system(Medyssey Co., Uijeongbu, Korea) as a semirigid rods.
Fig. 2
Fig. 2. Postroperative segmental dynamic angle changes at L3/4 (A) and L5/S1 (B) level.
Fig. 3
Fig. 3. (A) Radiographic evaluation or adjacent segment sagittal angle, and (B-D) postoperative fusion status.
Fig. 4
Fig. 4. Postoperative visual analog score (VAS) changes for back pain (A) and leg pain (B). SR, semirigid rod; RR, rigid rod.
Fig. 5
Fig. 5. Postoperative changes for functional (A) and economic (B) Prolo score. SR, semirigid rod; RR, rigid rod. *p<0.05, statistically significant differences between the 2 groups.
See this image and copyright information in PMC

References

    1. Ahn YH, Chen WM, Lee KY, Park KW, Lee SJ. Comparison of the load-sharing characteristics between pedicle-based dynamic and rigid rod devices. Biomed Mater. 2008;3:044101. - PubMed
    1. Akamaru T, Kawahara N, Tim Yoon S, Minamide A, Su Kim K, Tomita K, et al. Adjacent segment motion after a simulated lumbar fusion in different sagittal alignments: a biomechanical analysis. Spine (Phila Pa 1976) 2003;28:1560–1566. - PubMed
    1. Bono CM, Lee CK. Critical analysis of trends in fusion for degenerative disc disease over the past 20 years: influence of technique on fusion rate and clinical outcome. Spine (Phila Pa 1976) 2004;29:455–463. - PubMed
    1. Bridwell KH, Sedgewick TA, O'Brien MF, Lenke LG, Baldus C. The role of fusion and instrumentation in the treatment of degenerative spondylolisthesis with spinal stenosis. J Spinal Disord. 1993;6:461–472. - PubMed
    1. Cheh G, Bridwell KH, Lenke LG, Buchowski JM, Daubs MD, Kim Y, et al. Adjacent segment disease followinglumbar/thoracolumbar fusion with pedicle screw instrumentation: a minimum 5-year follow-up. Spine (Phila Pa 1976) 2007;32:2253–2257. - PubMed

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