Table 3.

Clinical studies considering vertebral compression fractures and postoperative management after spinal fusion.

Author	Year	Type of Study	Studies included	Study population	Aim	Main findings
Akai et al.[74]	2002	Meta-Analysis	5	180	Evaluate union rate of the fusion site, confirmed with X-ray, and clinical assessment	All studies showed a union of spine fusion confirmed with radio graphic assessment.
Akhter et al.[75]	2020	Systematic Review and Meta-Analysis	7	941	Determine the efficacy of postoperative electrical stimulation on radiographic fusion rates at a minimum 1-year follow-up in adult patients following spinal fusion, analyzing fusion rates relative to smoking status, numbers of levels fused and stimulation method	Electrical stimulation increased the fusion rate by 2.5 times relative to control in non-smokers and 2.8 times relative to control in smokers. The odds of a successful single level fusion were 3 times higher compared to control and 2.6 higher in multi-level fusions. Capacitive coupling had the greatest odds for successful fusion, followed by direct current and pulsed electromagnetic fields
Cottrill et al.[76]	2019	Systematic Review and Meta-Analysis	11 preclinical studies and 13 clinical studies	257 animals and 2144 patients	Overall effect of electrical stimulation technologies on spinal fusion, effect of DCS, ICS and CCS on spinal fusion	Electrical stimulation produced higher rates of fusion compared to control group but with an overall effect smaller than the preclinical studies. DCS and ICS lead to significant decreases in pseudarthrosis rates, whereas CCS does not.
D’Oro et al.[77]	2018	Retrospettive review		2613	Compare the number of patients who underwent a second surgery be- tween those who did and did not receive stimulation.	Among multi- level ALIF+PLF patients, those who underwent stimula- tion exhibited a significantly higher likelihood of revision surgery, null effects of stimulators on the revision rates among the other cohorts. physicians tend to pre- scribe stimulators for more complex and challenging cases (such as multi-level fusion or ALIF+PLF)
Fiani et al.[35]	2021	Review	9		Compare fusion rates of patients undergoing PEMF stimulation	Fusion rates ranged from 64% to 97.6% with PEMF stimulation and 43–86.7% for controls
Gan et Glazer[78]	2006	Review			Summarizes current concepts on the mechanisms of action, animal and clinical studies, and cost justification for the use of electrical stimulation for spinal fusions	DC stimulation to be superior to IC particularly when used to treat posterior spinal fusions. Data on CC therapy also indicate advantages over IC particularly for posterolateral fusions. However, it is not as statistically beneficial as DC for posterior spinal fusions.
Hijji et al.[79]	2018	Meta-analysis	6	924	Compare fusion rates after spinal fusion procedures between patients receiving either electrical stimulation or placebo treatments.	Fusion rates ranged from 35.4% to 90.6% in stimulation groups, and 33.3–92.8% in control groups. There was no significant difference in fusion rates between spinal stimulator and control groups (P = 0.067)
Kahanovitz[80]	2002	Review			Validate the use of various electrical stimulation devices as spinal fusion adjuncts.	Not all adjunctive electrical stimulation is equally effective: direct current is superior to PEMF particularly when used to enhance posterior spinal fusions. Also capacitive coupling shows clinical superiority over PEMF.
Oishi et Onest[81]	2000	Review	8		Provide the indications and limitations of electrical stimulation to enhance spinal fusion	Evidence supports its use for selected indications: multilevel fusion, reoperation for pseudoarthrosis and the presence of osteoporosis, smoking or significant vascular disease.
Tian et al.[82]	2013	Meta-analysis	21	1381	Determine Fusion rates using radiography or computed tomography.	No statistically significant differences among the three electrical stimulation methods with an overall fusion efficacy of 85%