Characteristics and Efficacy of a New 3-Dimensional Printed Mesh Structure Titanium Alloy Spacer for Posterior Lumbar Interbody Fusion

Abstract

This study evaluated the characteristics of a newly developed 3-dimensional printed mesh structure titanium spacer and its efficacy for posterior lumbar interbody fusion. Posterior lumbar interbody fusion with this spacer was performed at 53 segments (40 patients; mean age, 64 years; range, 51-73 years). Data were collected prospectively. Radiographic characteristics were analyzed with changes in interbody height, instability of the segments, formation of bone bridges around the implants, and pseudarthrosis, as determined by dynamic radiographs and postoperative computed tomography scans. Clinical outcomes were evaluated with the visual analog scale for the low back and extremities, the Oswestry Disability Index, and the 36-Item Short Form Survey. Radiographically, preoperative anterior and posterior interbody height was significantly increased immediately postoperatively (P<.05), and this increase was maintained until the last follow-up. No segmental motion of 3° or greater was noted at the last follow-up. Sagittal computed tomography images showed complete anterior bone bridges for 94.3% of cases and complete posterior bone bridges for 86.7% of cases. Coronal computed tomography images showed bilateral complete bone bridges for 94.3% of cases and unilateral bone bridges for 5.7% of cases without incomplete bilateral bone bridges. No pseudarthrosis or revision, particularly including posterior lumbar interbody fusion at L5-S1, was noted. Compared with preoperative values, the visual analog scale score for the low back and extremities, the Oswestry Disability Index, and the 36-Item Short Form Survey score showed significant improvement at the last follow-up (P<.05). Posterior lumbar interbody fusion with a newly developed 3-dimensional printed mesh structure titanium spacer showed satisfactory radiographic and clinical results, with no cases of pseudarthrosis or revision, including posterior lumbar interbody fusion at L5-S1. [Orthopedics. 2017; 40(5):e880-e885.].

3D-printed spine surgery implants: a systematic review of the efficacy and clinical safety profile of patient-specific and off-the-shelf devices

“…Titanium alloy (Ti6Al4V) was the material used to manufacture the spinal implants by 3DP (22/23 studies, 191 patients) in all but one study (Amelot et al [27]), which used PolyEther-Ketone-Ketone, or PEKK, implants for six patients. PS implant designs were used in 21 of 23 reviewed articles (5 case series, 14 case reports; 64 patients), whereas two case series [28,29] and a case report [30], respectively, were published on a generic (OTS) devices (135 patients), the Medussa-PL [29], K2M Lamellar Titanium Cage [28] and EIT Cellular Titanium interbody cage [30]. Thayaparan et al [30] implanted both PS and OTS 3DP devices.…”

“…The application of custom-designed implants was categorised into pedicle fixation rod (1 patient) [30], posterior arthrodesis cage (2 papers, 4 patients) [41,45], interbody fusion cage (5 papers, 5 patients) [34,[37][38][39]42], vertebral body replacement device (11 papers, 42 patients) [25-27, 34-36, 40, 43, 44, 46, 47] and miscellaneous sacral reconstructive device (3 papers, 12 patients) [31][32][33]. Utilisation of OTS devices manufactured using 3DP was limited to interbody fusion cages for degenerative pathology in the lumbar (3 papers, 134 patients) [28][29][30].…”

“…Achievement of bony fusion correlates with clinical outcomes of interbody fusion. Stable arthrodesis of titanium implants as adjudicated by the presence of a solid fusion mass with trabecular continuity bridging adjacent endplates through the graft volume was noted by seven PS papers [29,32,34,[37][38][39]44]. The present review application of radiolucent polymer biomaterials was limited to one PS study [27], and the remainder of PS implants and all current 3DP OTS interbody fusion cages evidenced in the literature were manufactured in Ti6Al4V.…”

Synthetic Bone Graft Materials in Spine Fusion: Current Evidence and Future Trends

“…Some groups have designed 3D-printed titanium cages with internal architecture that optimizes mechanical properties, osteoblast activity, and bony ingrowth. 57,58 These 3D-printed structures may have the potential to obviate the need for additional packing of ceramictype materials. Additive manufacturing provides an efficient means to control the microarchitecture, and subsequently, the biologic activity of a specific material.…”

Mechanical properties and fluid permeability of gyroid and diamond lattice structures for intervertebral devices: functional requirements and comparative analysis

“…Leading efforts to reduce the above problems concentrate on the employment of functional materials, such as superelastic alloys [8], and the development of porous [9,10] and patient-specific [11,12] spinal devices. Superelastic alloys have a lower modulus of elasticity than the traditionally used metallic implant materials.…”