The use of electrical stimulation to enhance spinal fusion

The goal of spinal arthrodesis is a solid osseous union across one or more spinal segments. A solid bone union after arthrodesis is commonly known as a spinal fusion. Surgeons have begun to understand the biomechanical and biological factors that influence the bone-healing process. One of the most commonly used adjuncts is spinal instrumentation. Instrumentation has increased the spinal fusion rate; however, fusion failure (that is, nonunion or pseudarthrosis) remains significant. A less commonly used adjunct is electrical stimulation (ES). Investigators in experimental studies have demonstrated the beneficial effects of ES on increasing the fusion rate. In this review the authors discuss the evidence concerning the benefits of ES as an adjunct to spinal arthrodesis. In addition, the different types of ES devices are described along with the current experimental and clinical evidence for each type of device.

Download Full-text

Novel spinal instrumentation to enhance osteogenesis and fusion: a preliminary study

Journal of Neurosurgery Spine ◽

10.3171/2016.1.spine13979 ◽

2016 ◽

Vol 25 (3) ◽

pp. 318-327 ◽

Cited By ~ 2

Author(s):

Matthew R. MacEwan ◽

Michael R. Talcott ◽

Daniel W. Moran ◽

Eric C. Leuthardt

Keyword(s):

Electrical Stimulation ◽

Quantitative Analysis ◽

High Resolution ◽

Bone Density ◽

Spinal Fusion ◽

Interbody Fusion ◽

Lumbar Fusion ◽

Spinal Instrumentation ◽

Ct Scanner ◽

Vertebral Bodies

OBJECTIVE Instrumented spinal fusion continues to exhibit high failure rates in patients undergoing multilevel lumbar fusion or pseudarthrosis revision; with Grade II or higher spondylolisthesis; or in those possessing risk factors such as obesity, tobacco use, or metabolic disorders. Direct current (DC) electrical stimulation of bone growth represents a unique surgical adjunct in vertebral fusion procedures, yet existing spinal fusion stimulators are not optimized to enhance interbody fusion. To develop an advanced method of applying DC electrical stimulation to promote interbody fusion, a novel osteogenic spinal system capable of routing DC through rigid instrumentation and into the vertebral bodies was fabricated. A pilot study was designed to assess the feasibility of osteogenic instrumentation and compare the ability of osteogenic instrumentation to promote successful interbody fusion in vivo to standard spinal instrumentation with autograft. METHODS Instrumented, single-level, posterior lumbar interbody fusion (PLIF) with autologous graft was performed at L4–5 in adult Toggenburg/Alpine goats, using both osteogenic spinal instrumentation (plus electrical stimulation) and standard spinal instrumentation (no electrical stimulation). At terminal time points (3 months, 6 months), animals were killed and lumbar spines were explanted for radiographic analysis using a SOMATOM Dual Source Definition CT Scanner and high-resolution Microcat II CT Scanner. Trabecular continuity, radiodensity within the fusion mass, and regional bone formation were examined to determine successful spinal fusion. RESULTS Quantitative analysis of average bone density in pedicle screw beds confirmed that electroactive pedicle screws used in the osteogenic spinal system focally enhanced bone density in instrumented vertebral bodies. Qualitative and quantitative analysis of high-resolution CT scans of explanted lumbar spines further demonstrated that the osteogenic spinal system induced solid bony fusion across the L4–5 disc space as early as 6 weeks postoperatively. In comparison, inactive spinal instrumentation with autograft was unable to promote successful interbody fusion by 6 months postoperatively. CONCLUSIONS Results of this study demonstrate that novel osteogenic spinal instrumentation supports interbody fusion through the focal delivery of DC electrical stimulation. With further technical development and scientific/clinical validation, osteogenic spinal instrumentation may offer a unique alternative to biological scaffolds and pharmaceutical adjuncts used in spinal fusion procedures.

Download Full-text

Electro-acupuncture reduces the need for additional anesthetics in experimental studies

Acta Cirurgica Brasileira ◽

10.1590/s0102-86502010000400015 ◽

2010 ◽

Vol 25 (4) ◽

pp. 381-384 ◽

Cited By ~ 3

Author(s):

Agamenon Honório Silva ◽

Alberico Ximenes do Prado Neto ◽

Sérgio Botelho Guimarães

Keyword(s):

Stainless Steel ◽

Electrical Stimulation ◽

Wistar Rats ◽

Experimental Studies ◽

Needle Insertion ◽

Additional Treatment ◽

Human Right ◽

Beneficial Effects ◽

Group Control ◽

Male Wistar Rats

PURPOSE: To evaluate the possible beneficial effects of electro-acupuncture in rats subjected to ketamine/xylazine (KX) intra-peritoneal (i.p.) anesthesia. METHODS: Forty-eight male Wistar rats were distributed in four equal groups. All rats received i.p. injections of ketamine (90 mg/kg) +xylazine (10 mg/kg) anesthesia. Basal values group (control) rats (BV) received no additional treatment. The equivalent of the human right ST36 (Zusanli) and CV-12(Zhongwan) acupoints were chosen for needling and electrical stimulation. AC rats were needled with sterilized disposable stainless steel needles at right ST36 and CV12 acupoints; needles were retained for 30 minutes. EAC10 rats, after needle insertion as described, had electrodes connected to both needles and to an electro stimulator model NKL EL-608; pulsed square waves, 10 Hz, 10 mA, was applied for 30 minutes. EAC100 rats were submitted to EA as described. However, a greater frequency (100 Hz) was used. RESULTS: Thirty-seven rats remained under adequate anesthetic level during the experiment. However, maintenance anesthesia was required by 11 rats. Need for additional anesthesia decreased to 9.1% in EAC100 rats compared to BV (36.3%). CONCLUSION: Both the AC and the EAC10/100 prolong the anesthetic effect of the combination Ketamine-xylazine in rats, allowing longer duration of anesthesia with a lower dose of anesthetic, thereby reducing the occurrence of complications.

Download Full-text

The Impact of Instrumentation and Implant Surface Technology on Cervical and Thoracolumbar Fusion

Operative Neurosurgery ◽

10.1093/ons/opaa321 ◽

2021 ◽

Vol 21 (Supplement_1) ◽

pp. S12-S22

Author(s):

Timothy Y Wang ◽

Vikram A Mehta ◽

Eric W Sankey ◽

Christopher I Shaffrey ◽

Muhammad M Abd-El-Barr ◽

...

Keyword(s):

Spinal Fusion ◽

Materials Science ◽

Spinal Instrumentation ◽

Spine Fusion ◽

Implant Surface ◽

New Era ◽

The Past ◽

Spinal Arthrodesis ◽

The Impact ◽

Existing Data

Abstract Spinal fusion has undergone significant evolution and improvement over the past 50 yr. Historically, spine fusion was noninstrumented and arthrodesis was based entirely on autograft. Improved understanding of spinal anatomy and materials science ushered in a new era of spinal fusion equipped with screw-based technologies and various interbody devices. Osteobiologics is another important realm of spine fusion, and the evolution of various osteobiologics has perhaps undergone the most change within the past 20 yr. A new element to spinal instrumentation has recently gained traction—namely, surface technology. New data suggest that surface treatments play an increasingly well-recognized role in inducing osteogenesis and successful fusion. Until now, however, there has yet to be a unified resource summarizing the existing data and a lack of consensus exists on superior technology. Here, authors provide an in-depth review on surface technology and its impact on spinal arthrodesis.

Download Full-text

Direct Current Electrical Stimulation Increases the Fusion Rate of Spinal Fusion Cages

Spine ◽

10.1097/00007632-200010150-00007 ◽

2000 ◽

Vol 25 (20) ◽

pp. 2580-2587 ◽

Cited By ~ 39

Author(s):

Jeffrey M. Toth ◽

Howard B. Seim ◽

Jeffrey D. Schwardt ◽

Wendy B. Humphrey ◽

Joel A. Wallskog ◽

...

Keyword(s):

Electrical Stimulation ◽

Spinal Fusion ◽

Direct Current ◽

Fusion Rate

Download Full-text

Exploratory meta-analysis on dose-related efficacy and morbidity of bone morphogenetic protein in spinal arthrodesis surgery

Journal of Neurosurgery Spine ◽

10.3171/2015.4.spine141086 ◽

2016 ◽

Vol 24 (3) ◽

pp. 457-475 ◽

Cited By ~ 21

Author(s):

Christoph P. Hofstetter ◽

Anna S. Hofer ◽

Allan D. Levi

Keyword(s):

Spinal Fusion ◽

Bone Morphogenetic Protein ◽

Interbody Fusion ◽

Meta Analysis ◽

Fusion Rate ◽

Control Group ◽

Complication Rates ◽

Lumbar Interbody Fusion ◽

Morphogenetic Protein ◽

Spinal Arthrodesis

OBJECT Bone morphogenetic protein (BMP) is frequently used for spinal arthrodesis procedures in an “off-label” fashion. Whereas complications related to BMP usage are well recognized, the role of dosage is less clear. The objective of this meta-analysis was to assess dose-dependent effectiveness (i.e., bone fusion) and morbidity of BMP used in common spinal arthrodesis procedures. A quantitative exploratory meta-analysis was conducted on studies reporting fusion and complication rates following anterior cervical discectomy and fusion (ACDF), posterior cervical fusion (PCF), anterior lumbar interbody fusion (ALIF), transforaminal lumbar interbody fusion (TLIF), posterior lumbar interbody fusion (PLIF), and posterolateral lumbar fusion (PLF) supplemented with BMP. METHODS A literature search was performed to identify studies on BMP in spinal fusion procedures reporting fusion and/or complication rates. From the included studies, a database for each spinal fusion procedure, including patient demographic information, dose of BMP per level, and data regarding fusion rate and complication rates, was created. The incidence of fusion and complication rates was calculated and analyzed as a function of BMP dose. The methodological quality of all included studies was assessed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Data were analyzed using a random-effects model. Event rates are shown as percentages, with a 95% CI. RESULTS Forty-eight articles met the inclusion criteria: ACDF (n = 7), PCF (n = 6), ALIF (n = 9), TLIF/PLIF (n = 17), and PLF (n = 9), resulting in a total of 5890 patients. In ACDF, the lowest BMP concentration analyzed (0.2–0.6 mg/level) resulted in a fusion rate similar to the highest dose (1.1–2.1 mg/level), while permitting complication rates comparable to ACDF performed without BMP. The addition of BMP to multilevel constructs significantly (p < 0.001) increased the fusion rate (98.4% [CI 95.4%–99.4%]) versus the control group fusion rate (85.8% [CI 77.4%–91.4%]). Studies on PCF were of poor quality and suggest that BMP doses of ≤ 2.1 mg/level resulted in similar fusion rates as higher doses. Use of BMP in ALIF increased fusion rates from 79.1% (CI 57.6%–91.3%) in the control cohort to 96.9% (CI 92.3%–98.8%) in the BMP-treated group (p < 0.01). The rate of complications showed a positive correlation with the BMP dose used. Use of BMP in TLIF had only a minimal impact on fusion rates (95.0% [CI 92.8%–96.5%] vs 93.0% [CI 78.1%–98.0%] in control patients). In PLF, use of ≥ 8.5 mg BMP per level led to a significant increase of fusion rate (95.2%; CI 90.1%–97.8%) compared with the control group (75.3%; CI 64.1%–84.0%, p < 0.001). BMP did not alter the rate of complications when used in PLF. CONCLUSIONS The BMP doses used for various spinal arthrodesis procedures differed greatly between studies. This study provides BMP dosing recommendations for the most common spine procedures.

Download Full-text