J Korean Neurosurg Soc.  2015 Jan;57(1):61-64. 10.3340/jkns.2015.57.1.61.

Radicular Pain due to Subsidence of the Nitinol Shape Memory Loop for Stabilization after Lumbar Decompressive Laminectomy

• Son BC
• Kim DR

• KMID: 2067094
• DOI: http://doi.org/10.3340/jkns.2015.57.1.61

Abstract

A number of dynamic stabilization systems have been used to overcome the problems associated with spinal fusion with rigid fixation recently and the demand for an ideal dynamic stabilization system is greater for younger patients with multisegment disc degeneration. Nitinol, a shape memory alloy of nickel and titanium, is flexible at low temperatures and regains its original shape when heated, and the Nitinol shape memory loop (SML) implant has been used as a posterior tension band mostly in decompressive laminectomy cases because the Nitinol implant has various characteristics such as high elasticity and a tensile force, flexibility, and biological compatibility. The reported short-term outcomes of the application of SMLs as posterior column supporters in cervical and lumbar decompressive laminectomies seem to be positive, and complications are minimal except for the rare occurrence of pullout and fracture of the SML. However, there was no report of neurological complications related to neural compression in spite of the use of the loop of SML in the epidural space. The authors report a case of delayed development of radiating pain caused by subsidence of the SML resulting epidural compression.

Keyword

Dynamic stabilization; Laminectomy; Nitinol; Pain; Shape memory loop

MeSH Terms

Alloys
Elasticity
Epidural Space
Hot Temperature
Humans
Intervertebral Disc Degeneration
Laminectomy*
Memory*
Nickel
Pliability
Spinal Fusion
Titanium
Alloys
Nickel
Titanium

Figure

• 

  Fig. 1 Radiologic findings of the patient. A : An anterior-posterior X-ray of the lumbar spine showing the placement of the shape memory loop and the posterior lumbar interbody fusion at the level of L4/5. B : A lateral X-ray of the lumbar spine. C : A sagittal T2-weighted image showing the encroachment of the shape memory loop (arrow) on the dural sac in the upper lamina of L4 and the lower lamina of L5. D : An axial T2-weighted image at the upper lamina level of L4.

• 

  Fig. 2 A : A sagittal reconstruction view of the CT-myelogram showing subsidence of the shape memory loop (arrow). An axial view of the CT-myelogram at the level of L4 (B) and L5 (C).

• 

  Fig. 3 A : An intraoperative photograph showing the placement of the shape memory loop. B : An intraoperative photograph showing the status of the upper limb of the shape memory loop at the level of L4 (right side). C : Drilling of the shape memory loop with a diamond burr. D : A photograph showing the presence of an epidural hole (arrow) made from the previous placement of the limb of the shape memory loop, causing dural compression.

Reference

1. Braun JT, Akyuz E, Udall H, Ogilvie JW, Brodke DS, Bachus KN. Three-dimensional analysis of 2 fusionless scoliosis treatments : a flexible ligament tether versus a rigid-shape memory alloy staple. Spine (Phila Pa 1976). 2006; 31:262–268. PMID: 16449897.

2. Il'in AA, Kollerov MY, Khachin VI, Gusev DA. Medical instruments and implants of titanium nicklide : physical metallurgy, technology, and application. Russian Metallurgy (Metally). 2002; 3:296–300.

3. Il'in AA, Kollerov MY, Sergeyv SV, Zagorodnyj NV, Radnaeyv EB, Nevzorov AV, et al. [Biologically and mechanically compatible implants from titanium nickelide in the treatment of damaged dorsal and lumbar spine]. Bull Traumatol Orthop. 2002; 2:19–26.

4. Kim DG, Eun JP, Park JS. Posterior cervical fixation with a nitinol shape memory loop for primary surgical stabilization of atlantoaxial instability : a preliminary report. J Korean Neurosurg Soc. 2012; 52:21–26. PMID: 22993673.

5. Kim YS, Zhang HY. Shape memory implant (KIMPF fixing) system. In : Kim DH, Cammisa FP, Fessler RG, editors. Dynamic reconstruction of the spine. New York: Thieme;2006. p. 292–298.

6. Kim YS, Zhang HY, Moon BJ, Park KW, Ji KY, Lee WC, et al. Nitinol spring rod dynamic stabilization system and Nitinol memory loops in surgical treatment for lumbar disc disorders: short-term follow up. Neurosurg Focus. 2007; 22:E10.

7. Mulholland RC, Sengupta DK. Rationale, principles and experimental evaluation of the concept of soft stabilization. Eur Spine J. 11(Suppl 2):2002; S198–S205. PMID: 12384745.

8. Sanders JO, Sanders AE, More R, Ashman RB. A preliminary investigation of shape memory alloys in the surgical correction of scoliosis. Spine (Phila Pa 1976). 1993; 18:1640–1646. PMID: 8235844.

9. Sengupta DK. Dynamic stabilization devices in the treatment of low back pain. Orthop Clin North Am. 2004; 35:43–56. PMID: 15062717.

10. Stoll TM, Dubois G, Schwarzenbach O. The dynamic neutralization system for the spine : a multi-center study of a novel non-fusion system. Eur Spine J. 11(Suppl 2):2002; S170–S178. PMID: 12384741.

11. Wever DJ, Elstrodt JA, Veldhuizen AG, v Horn JR. Scoliosis correction with shape-memory metal : results of an experimental study. Eur Spine J. 2002; 11:100–106. PMID: 11956914.

12. Yu DK, Heo DH, Cho SM, Choi JH, Sheen SH, Cho YJ. Posterior cervical fixation with nitinol shape memory loop in the anterior-posterior combined approach for the patients with three column injury of the cervical spine : preliminary report. J Korean Neurosurg Soc. 2008; 44:303–307. PMID: 19119466.