Growth and Regeneration of Intervertebral Discs by Electrophysiological Potential Therapy: Impedance Therapy

Abstract

Impedance therapy (IT) is an electrophysiological potential therapy where specific electrical impulses (SEI) stimulate the human body’s skin surface to cause a regenerative cascade in people diagnosed with degenerative disc disease (DDD). An observational retrospective cohort study sought to monitor the effect of IT, as an innovative nonpharmacological therapy that improves the health of DDD patients. The outcome was objectified by magnetic resonance imaging (MRI) of the spine, a neurological examination, patients’ own subjective feelings before and after electrotherapy, and confirmation of “disc grow-up” (DGU). The cohort was composed of 161 patients with an ICD diagnosis of G54.0,1,2,4 and/or M54.2,4,5,12,16,17, of whom 66 were women with a mean age of 54.7 years, and 95 were men with a mean age of 50.2 years. The cohort either had undergone or was undergoing IT rehabilitation with specific electrical impulses (SEI). A retrospective analysis of the data from patients who underwent IT rehabilitation in 2019 demonstrated a statistically significant 19% increase in intervertebral disc volume in cm³, p < 0.001 CI 95%, a reduction in pain perception after IT of 75%, p < 0.001 95% CI, and positive changes in tendon-periosteal reflexes (TPR), p < 0.01 CI 95%. IT offers new approaches to treating DDD with objective control of structural/degenerative/regenerative changes.

1. Introduction

DDD includes spondylotic, arthritic and degenerative disc disease of the spine, either with or without compression of nerve structures, or spinal instability [1, 2]. The main symptoms are axial pain, neck pain, back pain, upper/lower limb pain or a combination of any of them. An acute attack is expressed by the body’s inability to tolerate ongoing degeneration, localized in the spine structure. DDD-associated difficulties start with a metabolic imbalance developing at the cellular level in the connective tissue. It dominates in the largest avascular tissue found in humans, the intervertebral disc. The result is a degenerative cascade, according to Kirkaldy-Willisa [3]. The discs desiccate and lose height, volume, shape, elasticity and their optimal position to the adjacent vertebrae. The body becomes increasingly burdened with painful conditions, which are compensated by incorrect posture and positioning, reduced mobility and unevenly balanced loading of individual muscles and tendons. Fatigue sets in at a critical stage due to the lack or impossibility of movement and sleep, which significantly affects and limits a patient’s activities and possibilities. IT stimulates the skin surface with specific electrical impulses (SEI), which induce and restore the body’s own regeneration of soft tissue. This increases volume and adjusts the body to a physiologically more optimal shape, herniations recede, perforations heal and the intervertebral disc’s structure is restored. A secondary outcome is a reduction or significant resolution of the painful conditions DDD manifests. The method has been used in medical practice ever conclusions were drawn from a randomized clinical trial – impedance therapy in rehabilitation of degenerative disc disease and in accordance with them [4].

2. Degenerative disc disease diagnosis

When a patient has degenerative disc disease, it is important to identify where it hurts in good time, assess the severity and dynamics of developing concomitant medical symptoms, and provide him or her with the most effective therapy. Therefore, diagnosis and treatment require a multidisciplinary or team approach involving a general practitioner, neurologist, radiologist, neurosurgeon or spinal surgeon, algesiologist, orthopedic surgeon and physiotherapist. It is also critical to identify the source of vertebrogenic pain early, likewise assess the severity and dynamics of developing concomitant medical symptoms, and provide patients with the most effective treatment for the disease. Radiological findings (native X-ray, CT or MRI) have confirmed that degenerative lumbar spine disease (DLSD) is going to affect 100% of the population over 40 years of age, and a severe degree will have an impact on 60% of the population over 70 [1, 5]. However, the correlation between the degrees of degenerative changes confirmed by imaging and subjective or objective clinical symptoms is low, and so many patients with radiological findings remain free of difficulties [6, 7]. In symptomatic patients, degenerative changes in the discs and facet joints, degenerative spondylosis, soft tissue changes of the spine and compression of nerve structures and roots in the lumbar spinal canal and/or exiting neuroforamina contribute significantly to discomfort. However, discrepancies between the structural changes detected by a CT scan or MRI and clinical findings often impede accurate identification of the source of pain, for example, in surgical procedures, or in minimally invasive or endoscopic surgery. Indeed, the structural changes depicted may frequently not be causally related to clinical symptomatology. Therefore, a misleading diagnosis is not rare and can lead to failure of conservative or surgical treatment and sometimes even to disability [8, 9]. A specific condition requiring urgent neurosurgical attention is acute cauda equina syndrome. It is caused by compression of the cauda equina and is associated with a large medial herniation of the lumbar disc.

Based on conclusions drawn from medical observations, we confirm that the onset of back pain, as a consequence of DDD, takes place predominantly when there is a pattern of peripheral sensitization [10]. The following has been observed in such cases:

• Painful conditions arising without stimulus;

• Damage (mechanically by compression or inflammation) of the sensory nerves leading to nociceptive afferent C unmyelinated fibers;

• Lactic acid accumulating in the degenerated disc with the subsequent acidosis stimulating the nociceptors;

• Production of cytokines – nociceptive molecules;

• Susceptibility of spinal nerve roots to compressive damage because a well-developed blood-nerve barrier is missing;

• In the acute stage, abnormal accumulation of sodium channels in the nociceptors and ganglia of the posterior horns of the spinal cord, with a consequent decrease in the depolarization threshold;

• Increased number of adrenergic receptors and circulating catecholamines;

• Sprouting of neurons and new nerve fiber outgrowth at the site of nerve fiber severance during a period of regeneration. Increased irritability is visible due to the increased concentration of sodium and calcium channels.

These changes raise the sensitivity of nociceptors to various, even painless stimuli and peripheral sensitization and lead to the development of spontaneous ectopic activity in the damaged nerves.

The four sources of pain recognized In DDD are discogenic and facet pain, pain from spinal stenosis and radicular pain [11]. Discogenic pain is associated with pathological neovascularization and axonogenesis of the intervertebral disc. Nerve fibers, accompanied by blood vessels, grow into the cracks that appear in degenerate discs. In addition, vascularized granulation tissue and extensive innervations form and extend from the outer layer of the annulus fibrosus to the nucleus pulposus. The rate of unmyelinated C-fiber and micro-vessel growing in the intervertebral disc to the depth of the nucleus pulposus of the spine [11] is directly proportional to the rate of degenerative changes associated with discogenic pain. Nociceptive discogenic pain is caused by stimulation of sensory nerve endings (peptidergic substance P [SP], CGRP-calcitonin gene-related peptides [CRGP] and vasoactive intestinal polypeptides [VIP]) in the outer layers of the annulus fibrosus. Another source of discogenic pain is structural failure of the intervertebral disc. When it is burdened, so-called “peripheral sensitization” can cause the usually innocuous mechanical stimuli of nociceptors in the annulus fibrosus to amplify nociceptive stimulation. In degenerated joints, facet pain comes from the ingrowth of blood vessels and unmyelinated C-fibers and radiates from the subchondral bone into the interior of the damaged articular cartilage. The inflammatory cytokines IL-1b and TNFα sensitize nerve fibers, increasing pain transmission and hyperalgesia [2]. Patients with severe facet joint degeneration feel a burning pain. Pain from spinal stenosis develops from hypertrophy of the bony and ligamentous structures, combined with disc bulging in the spinal canal and around the neuroforamina, compressing the nerve roots and making them dysfunctional. The presence of the inflammatory cytokines IL-1b, TNFα, and IL-6 in the facet joints contributes toward the development of pain [12]. Cytokine levels are higher in patients with lumbar spinal stenosis (LSS) than those with herniated discs.

Nociceptive radicular pain, with no concomitant neurological nerve root damage, is felt when the nociceptors in the perineurium of the nerve root are stimulated. It is caused by ectopic discharges from damaged posterior roots or their ganglia. A diagnosis of “definite” neuropathic radicular pain requires the presence of objective sensory symptoms (hyperalgesia, dysesthesia, hypesthesia and allodynia) either with or without motor signs of radiculopathy, while the presence of isolated motor symptoms of radiculopathy is enough for a diagnosis of “probable” neuropathic radicular pain. Conservative treatment of DDD with gabapentin has been ineffective because, in this type of pain, it acts on central sensitization and not on the onset of the painful condition itself [12].

3. Impedance therapy

The key building block in impedance therapy (IT) is the specific electrical impulse (SEI). Alternating SEIs from a current or voltage generator stimulates the body via electrodes placed on a patient’s skin. Output current up to 3 mA is used, with consumption up to 5VA. Applying an SEI elicits a sympathetic skin response [11, 13]. This is confirmed by a change in skin conductance due to the changed conductivity of the sweat produced by it. Repeatedly pooled therapeutic procedures provide adequate data to confirm correlation dependencies for SEI frequency and amplitude; stable and dynamic portions of the SEI; electrode surface, size and insulation resistance; and other parameters for defining the baseline SEI stimulation sequence and determining the dynamic SEI [11]. The SEI structure most capable of effectively increasing skin conductance is one that can induce a harmonic change in skin resistance. In IT, the slowed response to regenerative induction highlights the body’s inability to react to a harmonic change, so the therapy takes advantage of the feedback response in the patient’s body. Therefore, stimulation comes from the body’s previous response. It is evaluated in real-time by an information system with a knowledge base. Unless there is an active feedback loop in the internal information system, the SEI’s full regenerative effect on the body cannot be ensured. Under the influence of IT, nonphysiological, unmyelinated C-fibers are effectively reduced, eliminating discogenic pain. Follow-up DICOM images from MRI scans confirm reparative changes in the intervertebral disc after completion of the first block of planned long-term rehabilitation. The observed changes are predominantly at the level of reducing intervertebral disc fissures, which are visible on MR images as desiccated changes. Impedance therapy’s effectiveness and success are therefore evident in healed cracks and perforations, reduction of the hernia and increased elasticity. Yet these regenerative/reparative processes are dependent on the degree of DDD and the dynamics of degenerative structural changes. A patient can be cured of this disease of civilization (DDD) after having completed a long-term IT rehabilitation plan. Since impedance therapy has been around for over 20 years, information systems have been keeping medical records of all successfully treated patients who have enrolled in a long-term rehabilitation plan.

Timeline of medical practice established concepts and procedures in electrophysiological potential therapy:

• 2000 - Electrophysiological regenerative potential therapy, later called electrophysiological potential therapy

• or impedance therapy (2005).

2009 - Disc grow-up (DGU). The term refers to confirmed growth in intervertebral disc volume after the completion of a long-term IT rehabilitation plan involving SEIs. It confirms not just the gradual elimination of painful conditions but also the change in the disc’s structure, a reduction in perforations and disc herniation, and so the elimination of degenerative changes in the spine. Ongoing follow-up measurements of patients who have undergone not just impedance therapy confirm that the regenerated intervertebral disc keeps its condition even several years after long-term rehabilitation ends, at a time when a patient is no longer receiving IT. On the other hand, patients treated with standard nonsurgical procedures only had intervals of slowed progression of degenerative changes recorded. These alternated with intervals of re-accelerated degeneration. Clinical practice consistently confirmed the validity of the unidirectional degenerative cascade mentioned by Kirkalda-Willis [5] until the patient’s body received SEIs.

2014 – Initial blood screening introduced with impedance therapy patients receiving detailed blood analysis. Among other things, changes in plasma blood lactate levels from capillary blood and VZV, CMV, HSV and EBV IgG levels were monitored.

2016 – Correlational evaluation of blood screening. The first dependence was recorded on the size of intervertebral disc growth on IgG-VZV, CMV, HSV and EBV IgG levels, with concordant harmonization of blood lactate levels at rest and later during exercise. Continuing medical observations and initial correlational analyses of sample data have empirically demonstrated and continue to demonstrate a dependence between the magnitude of increased intervertebral disc volume and the magnitude of higher plasma VZV, CMV, HSV and EBV immunoglobulin levels in the first block of a long-term rehabilitation plan with IT.

2016–2018 – “Impedance therapy in rehabilitation of degenerative disc disease,” a clinical study that confirmed the DGU phenomenon [4].

4. Retrospective cohort study

An observational retrospective cohort study sought to monitor the effect of IT at the level of an innovative nonpharmacological therapy that improves the health of patients with DDD. It was objectified by magnetic resonance imaging (MRI) of the spine, 3D visualization of DICOM images from MRI scans together with an assessment of the DUG phenomenon, a neurological examination and patients’ own subjective feeling before and after electrotherapy.

4.1 Participants

Retrospective data processing covered 161 patients (Table 1) with an ICD-10 diagnosis of G54.0,1,2,4 and/or M54.2,4,5,12,16,17 who had undergone impedance therapy. There were 66 (41%) women and 95 (59%) men with a mean age of 50 (11) and 55 (13) years, respectively. Data from all patients who had cervical and lumbar disc volumes evaluated from January 2019 to December 2019 were included. For retrospective analysis, the criteria below were used in the processing of data on patients who had undergone IT. Consent was given by all patients whose data had been retrospectively processed to the therapy, and they were informed of the possibility to opt out of participation in the monitoring of treatment and its effects at any time. Written consents to the anonymous use of data were archived. In order to analyze the 2019 retrospective study and confirm the effects of impedance therapy, every patient’s informed consent was kept according to his or her long-term rehabilitation plan after each medical procedure over the time impedance therapy was applied. Design and flow of participants through the trial All administrative processes complied with the guidelines set out in the Declaration of Helsinki [6].

Participants	Male	Female
Age (years) Mean (SD)	50.3 (11.3)	54.7 (12.6)
N	95 (59%)	66 (21%)

Table 1.

Characteristics of participants.

4.2 Methods

A clinical retrospective trial sought to monitor the effect of IT at the level of an innovative nonpharmacological therapy that improves the health of patients with DDD. It was objectified by magnetic resonance imaging (MRI) of the spine, 3D visualization of DICOM images from MRI scans together with an assessment of the DUG phenomenon, a neurological examination and patients’ own subjective feeling before and after electrotherapy. A study was conducted with a retrospective analysis of data from the medical records of patients who had undergone rehabilitation at the optimal duration of 5–7 months and completed the first block of their planned rehabilitation between January and December 2019. All of the data processed in the retrospective analysis from the application of electrophysiological potential therapy on patients consisted of anonymized case report forms (CRF) on patients from the outpatient information system.

4.3 Intervention – Rehabilitation

It consists of three blocks of therapies and their associated phases:

Block I focused on reducing pain. It involved the application of standard physiotherapy procedures in combination with impedance therapy.

Phase 1 - Classification.

Phase 2 - Reverse transcription (RT) symptoms.

Phase 3 - Enrollment in kinesiotherapy.

Block II focused on stress testing to increase physical performance in feedback control.

Phase 4 - Enrollment in training sessions.

Phase 5 - Analysis of metabolism.

Phase 6 - Fixation of regeneration.

Block III focused on maintaining proper exercise frequencies and correct weight. Muscle load measurements with a defined blood lactate level.

Patients whose data had been processed in the retrospective study underwent rehabilitation three times every 2 weeks for a total of 29–48 therapy sessions that each lasted between 90 and 120 minutes. The length of each planned rehabilitation was always dependent on the patient’s DDD condition, with the patient’s comorbidities being an important factor.

Every patient whose data was processed had undergone the following during therapy:

1. Examination of tendon-periosteal reflexes before and after therapy

2. Electrophysiological potential therapy (IT) with a physiotherapy muscle stimulator (PSS)

3. Heat and light therapy (TDP® lamp, Biolamp, Biolaser L1)

4. Dry needling

5. Manual therapy by a physiotherapist

6. Measurement of capillary blood lactate levels [4].

4.3.1 Methods for monitoring safety and accuracy

1. Adverse event monitoring was used to observe each patient’s local and systemic tolerance to medical treatment and procedures. Patients were under the direct control of medical staff during every impedance therapy session.

2. During electrophysiological potential therapy, every patient was exposed to physical loads at output currents up to 3 mA, with consumption up to 5VA. Prior to each SEI application to a patient’s body, an artificial resistive load with a dynamic waveform was used for control purposes to measure current and voltage from the alternating electrical pulse generator.

3. The trifilar winding at the generator cores was measured at the beginning of each day of therapy. Throughout SEI application, the generators exhibited tolerances within 0.05% of the measured electrical parameters.

4. No notes were made during IT of either electrical inaccuracies or generator failure in patient records that were processed for retrospective analysis.

5. Comparisons made of the outcomes in individual patients were based on anonymized patient data, which was also subordinated to the composition of the final CRF.

6. Intervertebral disc volume was assessed with a DICOM image converter [14].and a magnetic resonance imaging scan, which has a negligible error rate.

7. The precision of MRI equipment was defined from a sample calibration volume that was measured in each MRI scanner. In the retrospective cohort study, a bias of up to 0.9% was accepted. All patients also carried on them a foreign object with a well-defined calibration value to measure the precision of the MRI scan while.

4.3.2 Outcome measures

Primary outcome: Data recorded for each patient over a period before impedance therapy and after a series of therapies were retrospectively evaluated [4]:

1. Pain perception. Pain is assessed on a scale of 1–10 (1 = no pain, 10 = unbearable pain) [4].

2. Magnetic resonance (MR) imaging. MR images were used to visualize the discs in 3D, with the findings evaluated in DICOM files in order to assess and compare the effect of the therapy. The DICOM images were processed by InVesallius a DICOM data converter program (Paulo 2014). DGU was subsequently confirmed by visions of images of regenerated intervertebral discs that had healed and grown. A Siemens 1.5 T MRI scanner provided the MR images. They were produced in the following sequences:

   1. transversal T2 weighted images,

   2. sagittal T2 weighted images and 3D data. The sequences were always at the same level, with a 1-millimeter-thick cross-section. The standard number of cross-sections was 19 ± 3 per sequence. InVesalius then converted the DICOM images to the STL (stereolithography) file format, with MR scanning subtracting the imaged part. The images were then evaluated by a neurologist, radiologist or neurosurgeon.

      • Standardized volume was measured on each of the MRI scanners prior to the start of treatment. The exact reference volume was then imaged on an MRI scanner, and a 3D reconstruction was created. This provided evidence of its precision and accuracy.

      • Based on our observations, the standard deviation of magnetic resonance machine precision in Slovakia was calculated at about ±10%.

      • For the study, a ± 0.68% bias was accepted.

3. Neurological examination of tendon-periosteal reflexes. Reflexes are assessed on a scale of 1–7 (0 = reflexes not manifested, 3 = average reflexes, 6 = strong reflexes) [4].

4. Assessment of capillary blood lactate levels – complementary measurement. An indicator of fatigue is the level of lactate in the blood, where long-term increased concentration causes metabolic acidification in the body’s internal environment. Because fatigue also decreases body performance, blood lactate levels were measured both at rest and during artificial exercise. The mean blood lactate levels displayed in Table 2 are after 10–30 minutes of exercise (before and after enrollment in the study). The reference blood lactate level at rest is 0.7–1.8 mmol/L. A blood lactate value of 4 mmol/l during exercise is generally considered to be the limit of the body’s efficiency for a patient used to exercising. Patients that are recreational athletes can push their blood lactate limit up to 5.5 mmol/l. Measuring blood lactate levels provides information for monitoring improvement in the body’s physical condition from impedance therapy [4].

Spine	Gender	Aero		Rest
		Before	After	Before	After
Lumbar	Male (N = 58)	7.4 (1.3)	5.3 (0.8)	3.3 (0.5)	1.5 (0.3)
	Female (N = 36)	7.9 (1.7)	5.5 (0.7)	3.1 (0.4)	1.4 (0.3)
Cervical	Male (N = 37)	7.9 (1.4)	5.5 (0.8)	3.3 (0.5)	1.4 (0.3)
	Female (N = 30)	7.9 (1.4)	5.3 (0.7)	3.2 (0.5)	1.4 (0.3)

Table 2.

Statistical analysis of lactate values.

Design and flow of participants through the trial it shows in Figure 1.

Figure 1.

Design and flow of participants through the trial.

4.3.3 Data analysis

Descriptive statistics, which compares input and output data, was used to process the data obtained. Information about the normal distribution of the data and the equality of variances was found from the Kolmogorov-Smirnov and Shapiro-Wilk normality tests and Levene’s test of variances. If the significance of both tests at the alpha level is greater than 0.05, then the data and variances are normally distributed. Concurrently, the Student’s t-test was used for evaluation. If the significance of the test of normality or variance at the alpha level is less than 0.05, it is a selection with a disrupted normal distribution of the data or variances, and so a nonparametric statistical significance test would be used for the evaluation, in this case, the Wilcoxon signed-rank test. A standard measure of the magnitude of our observations came from effect size. To process the data, MS Office Excel 2007 and SPSS 16 statistical software were used.

4.4 Results

Retrospective data were processed for 161 patients with an established ICD diagnosis of G54.0,1,2,4 and/or M54.2,4,5,12,16,17. There were 66 (41%) women and 95 (59%) men with a mean age of 50 (11) and 55 (13) years, respectively (Table 1). Due to the homogenized population, data from both the cervical and lumbar regions were statistically processed. Among the female patients, data was collected from the cervical and lumbar regions of 30 and the lumbar regions of 36. In the case of the male patients, data was taken from the cervical regions of 37 and from the lumbar region of the remaining 58.

The retrospective study for 2019 of the data obtained showed intervertebral disc volume to have risen in the men, due to DGU, at 3.2 cm³ (21%) (95% CI) in the lumbar region and at 0.4 cm³ (19%) (95% CI) in the cervical region. In the women, these figures were 2.2 cm³ (16%) (95% CI) and 0.4 cm³ (25%) (95% CI), respectively. Table 3 shows the increase in disc volume among both sexes and in both spinal regions studied to be highly statistically significant (p < 0.001). The pre- and post-IT magnetic resonance images in Figures 2–7 objectify the treatment of patients with degenerative spine disease.

Spine	Gender	Disc volume (cm^3)
		Before	After
Lumbar	Male (N = 58)	15.4 (4.9)	18.6 (5.1)
	Female (N = 36)	13.2 (4.3)	15.4 (4.5)
Cervical	Male (N = 37)	2.2 (0.5)	2.7 (0.5)
	Female (N = 30)	1.6 (0.3)	1.9 (0.30)

Table 3.

Mean (SD) of disc volume.

Figure 2.

MRI image of the lumbar spine before IT (female, 1997).

Figure 3.

MRI image of the lumbar spine after IT (female, 1997).

Figure 4.

MRI image of the lumbar spine before IT (female, 1982).

Figure 5.

MRI image of the lumbar spine after IT (female, 1982).

Figure 6.

MRI image of the cervical spine before IT (male, 1980).

Figure 7.

MRI image of the cervical spine after IT (male, 1980).

A reduction of pain was noted in the lumbar region by 4 points (78%) (95% CI) of the men and in the cervical region by 3 points (68%) (95% CI) of them. Among the women, 4 points (78%) (95% CI) of them experienced a reduction of pain in the cervical region and 4 points (73%) (95% CI) in the lumbar region. A highly statistically significant reduction of pain (p < 0,001) was documented in both sexes and both study areas (Table 4).

Spine	Gender	Pain
		Before	After
Lumbar	Male (N = 58)	5.3 (1.6)	1.2 (0.4)
	Female (N = 36)	6.1 (2.3)	1.7 (0.7)
Cervical	Male (N = 37)	4.5 (1.4)	1.4 (0.6)
	Female (N = 30)	5.5 (2.2)	1.2 (0.5)

Table 4.

Mean (SD) of pain perception.

1 = no pain, 10 = unbearable pain.

Records obtained from entrance and exit neurological examinations, specifically in tendon-periosteal reflexes, showed highly statistically significant changes of p < 0.01 in both cohorts. The exception was among women who showed no normalized tendon-periosteal reflexes in the lumbar region, at a statistically significant p = 0.064 (Table 5). The processing of tendon-periosteal reflex data was based on optimizing their amenability, which equals a median value of 3.

Spine	Gender	Tendon-periosteal reflexes
		Before	After
Lumbar	Male (N = 58)	1.9 (1.1)	2.6 (0.5)
	Female (N = 36)	2.2 (1.3)	2.5 (0.6)
Cervical	Male (N = 37)	1.6 (0.8)	2.8 (0.4)
	Female (N = 30)	1.7 (1.0)	2.6 (0.5)

Table 5.

Mean (SD) of tendon-periosteal reflexes.

0 = reflexes not manifested, 3 = average reflexes, 6 = strong reflexes.

The medical information obtained while examining the blood lactate level during the second block of planned long-term rehabilitation showed (Table 2) when DGU was confirmed in a patient, the blood lactate level could be adjusted to the second block’s physiological parameters. This change in the lactate level is associated with the end of long-term rehabilitation and termination of treatment after the patient no longer requires medical care. Table 6 summarizes the results from the monitoring of the entire population.

	N	Before	After
Disc volume (cm^3)	161	9.3 (7.2)	11.1 (8.4)
Pain (points)	161	5.3 (1.9)	1.4 (0.6)
PTR	161	1.8 (1.1)	2.6 (0.5)

Table 6.

Means (SD) of disc volume, tendon-periosteal reflexes and pain perception.

The outcome of treatment was considered to have been successful:

1. If conversion and comparison of DICOM magnetic resonance images before and after a patient underwent planned rehabilitation confirmed morphological changes in intervertebral discs caused by DGU.

2. If comparative neurological examinations showed improvement.

3. If the patient subjectively considered his or her condition to have improved because of the loss or significant reduction of pain complications, allowing him or her to return to original and not only self-supporting activities.

4.5 Discussion

The objective of the retrospective study was to monitor the effect of an innovative electrophysiological potential therapy, impedance therapy, on improving the condition of DDD patients and to confirm growth in intervertebral discs due to the DGU phenomenon. The outcome confirms the positive effect from impedance therapy in the enlargement and increased size of intervertebral discs. Evidence was provided by magnetic resonance imaging (MRI) scans of patients, which exactly demonstrated the disc grow-up (DGU) phenomenon.

Conservative treatment, rest and adequate medical therapy and rehabilitation are effective in 85–90% of patients at the level of their subjective symptoms. Surgery is indicated in 10% of the patients where radicular irritation persists and/or neurological deficit progresses with conservative treatment. Rare syndromes and progressive motor radicular deficits require urgent surgical treatment [15]. The remaining 5–10% of patients remain chronically disabled, especially with back pain, despite the treatment available. Surgery for patients with chronic back pain has not been very successful. Surgery is indicated when there is significant functional incapacity or pain is unresponsive to multidisciplinary conservative treatment. The prognosis for patients is influenced by the severity of the clinical manifestation, the possibility of providing rapid adequate treatment and psychosocial-economic factors. Degenerative changes of the spine as a disease of civilization could have been treated by standard medical or nonmedical treatment but never eliminated [4, 7, 16]. This reported retrospective study traces the emergence of the DGU phenomenon under the influence of IT. Evidence of intervertebral disc growth after SEIs because of DGU was first confirmed in “Impedance therapy in rehabilitation of degenerative disc disease a clinical randomized trial in a cohort composed of 55 patients with an ICD diagnosis of G54.0,1,2,4 and/or M54.2,4,5,12,16,17 and averaging 51 years of age. They were divided into monitored and control cohorts [4]. A total of 61 patients were enrolled in the study, from which six of the patients were excluded, four because of the exclusion criteria and two opted to discontinue their participation in the study. The first monitored cohort comprised 29 patients with a mean age of 57 (11) years. It had 22 (76%) men and 7 (24%) women whose average ages were 57 (12) and 55 (13) years, respectively. They received impedance therapy. This electrophysiological potential therapy produced changes in the health of the monitored cohort of patients when they followed the changes mapped out in the rehabilitation plan. Patients included in the cohort underwent a period of reverse transcription (RT) symptoms, which involved the reappearance of past difficulties, although they were less intensive. The presence of RT symptoms was a manifestation of DGU-caused intervertebral disc regeneration. The other control cohort consisted of 26 patients with a mean age of 46 (11) years. It had 10 women with the same average age as the control cohort and 16 men whose mean age of 46 (13) years. They received standard electrotherapy. There was a transient improvement in their condition noted during the first 3–4 weeks. Subsequently, it varied harmoniously between the painful conditions experienced before they were enrolled in the therapeutic block and periods of subjective feelings of good health.

In the monitored cohort, intervertebral disc growth was demonstrated in 76% of the patients, where the DGU phenomenon was confirmed in 22 patients (intervertebral disc volume increased by more than 10%). There was no evidence of the DGU phenomenon in 24% of the patients from the application of impedance therapy and no reduction in intervertebral disc volume either. DDD did not progress (intervertebral disc volume rose 0–5%) [4]. Existing available references list a number of studies that examined the use of physiotherapy in patients with degenerative spinal conditions, looking only at the impact on pain, range of motion in the spine and quality of life. In a review study, Kroeling [17] included 20 studies involving a total of 1239 patients, where the cohorts consisted of adult patients aged more than 18 years with both acute and chronic cervical spine pain or nonspecific pain, including degenerative changes, myofascial pain and headaches that originated from the cervical region. The outcomes from these studies could not be pooled because different populations had been examined, and there were different types and dosages of electrotherapy and comparative treatments with moderately different results measured. The CENTRAL, MEDLINE, EMBASE, MANTIS, CINAHL and ICL databases were searched with no language restrictions until August 2012. The results from these searches indicated that transcutaneous electrical nerve stimulation (TENS) had a more significant effect on pain reduction in patients with acute pain than electrical stimulation, exercise, infrared light, manual therapy and ultrasound. Efficacy was not statistically significant for combinations of infrared light therapy, thermotherapy and kinesiotherapy, nor the combination of cervical collar, exercise and pharmacotherapy. In patients with chronic cervical spine pain, TENS probably relieved pain as well or better than a placebo or electrical muscle stimulation, although not as well as exercise and infrared light. However, a similar effect was obtained with a combination of manual therapy, mobilization techniques and ultrasound [17]. Lau [18] published a randomized trial describing two physiotherapy phases, where the first phase consisted of movement therapy and interferential currents were indicated in the second phase. In the acute stage of the disease, either pharmacotherapy or soft relaxation techniques are recommended for back pain [18]. Hayden [19] in review found evidence that Pilates, McKenzie therapy and functional restoration were more effective than other types of exercise treatment for reducing pain intensity and functional limitations. Nevertheless, people with chronic low back pain should be encouraged to perform the exercise that they enjoy to promote adherence. In addition to IT, rehabilitation in our study includes exercise and continued physical activity.

A retrospective study of electrophysiological potential therapy - impedance therapy in 2019 showed the following:

1. Statistically significant growth in intervertebral disc volume at 2.8 cm³ (19%) (p < 0.001).

2. A 4 (75%) points reduction in pain perception after IT (p < 0.001), with an exit neurological examination specifically demonstrating statistically significant changes in tendon-periosteal reflexes (p < 0.01).

4.6 Medical observations from the study

1. Based on empirical findings, the success and effectiveness of impedance therapy were dependent on the degree of DDD and the dynamics of degenerative structural changes.

2. A necessary condition for inducing regenerative processes was the regular frequency of impedance therapy (optimally three times every 2 weeks with an assessment of DGU after the first block).

3. The records of patients that had received impedance therapy documented changes in their condition that followed the course of changes described in the long-term rehabilitation plan.

4. Patients enrolled in impedance therapy underwent a period of RT symptoms and this is evidence of correctly applied impedance therapy. A reverse transcription symptom marks the reappearance of past difficulties albeit with less intense pain and no objective change in the patient’s level of mobility. The presence of RT symptoms is a manifestation of DGU-caused intervertebral disc regeneration. Their significance comes not only at the level of having analyzed a correctly applied therapy. The presence of these symptoms is confirmed by the following:

   • Changes in capillary blood lactate level

   • Change in tendon-periosteal reflexes

   • Changes in muscle tension

   Reverse transcription symptoms appeared at two separate time intervals:

   • The first set of RT symptoms are predominantly linked to SEI-induced changes in blood lactate levels and take place between four and 8 weeks into planned long-term rehabilitation.

   • The second set (between 14 and 18 weeks into planned long-term rehabilitation) is linked to rapid intervertebral disc decompression. It more markedly irritates other unmyelinated C-fibers, whose stimulation appears because of peripheral sensitization. After the second set of RT symptoms, an MRI of the patient was indicated, followed by evaluation and 3D visualization by InVesalius of the intervertebral disc. Confirmation of the DGU phenomenon translates into the completion of the first block of the long-term rehabilitation plan and the patient’s continuation in the second block, which focuses on increasing his or her exercise capacity and adjusting weight.

5. The inability of the body to respond to IT with a harmonious change in resistance highlighted the body’s own slowed capability to regenerative induction, slowing the increase in intervertebral disc volume (the DGU phenomenon).

6. The effect of IT on a patient’s pain in confirmed DDD cases has been demonstrated in the controlled reduction in the number of new, unwanted protrusions of sensitive nerve fibers that have sprouted. These show increased irritability due to the increased concentration of sodium and calcium channels.

7. The effect on unmyelinated C-fibers was demonstrated when the following was observed:

   • Changes in skin conductance or the psychogalvanic reflex (PGR) [9, 13];

   • Increase in intervertebral disc volume, reduction and gradual disappearance of DDD-typical structural changes and reduction of discogenic pain where the source was black disc, a degenerative disc disease [8].

8. Unless there is an active feedback loop in the internal information system and pooling, the full therapeutic impact of IT on a patient’s body cannot be ensured.

   Other diagnostic criteria for enrollment into impedance therapy:

   • Degenerative disc disease (DDD)

   • Recurrent back pain and no proven degenerative spinal disease

   • Hernia of the intervertebral disc up to 9 mm and extending into the spinal canal without sequestration

   • Impaired aerobic and anaerobic thresholds and simultaneously confirmed degenerative disc disease without subjective symptoms

   • Listhesis of the lumbar or cervical spine

   • Spinal block with or without back pain

   • Diabetic polyneuropathy in the lower extremities

   • Tennis and golfer’s elbow

   • Gonarthrosis with no traumatic etiology

   • Chronic fatigue syndrome

   • Exhaustion

   • Histamine imbalance

5. Conclusion

Impedance therapy, an electrophysiological potential therapy, offers a new perspective on the course, prognosis and therapy for a disease of civilization, namely degenerative disc disease. The probability of reversing these structural degenerative changes is documented in the outcome of this study. It confirmed the possible active intervention in the degenerative cascade of the three-joint complex in individual movement segments of the spine, described by Kirkaldy-Willis in the 1970s. We believe that the effect and exact results of impedance therapy have disproved the theory of irreversible degenerative changes in the spine.

1. The outcome confirms the positive effect from impedance therapy in the enlargement and increased size of intervertebral discs. Evidence was provided by magnetic resonance imaging (MRI) scans of patients that exactly demonstrated the DGU phenomenon.

2. Impedance therapy has been applied as an innovative treatment for degenerative disc disease with an objectively measurable result of recovery for a patient’s body in active medical practice.

3. The feedback loop for the next SEI, once a response to the previous SEI has been evaluated after a defined time interval, is critical to the application of impedance therapy. The prerequisites for IT to be applied were meeting inclusion criteria and the diagnostic conditions for impedance therapy in the rehabilitation plan.

4. Applying SEIs in electrophysiological potential therapy actively contributed to the elimination of DDD-caused pain. The first step in the application of impedance therapy focuses on removing structural changes no one can influence at their own volition. Later, the burden of regeneration shifts more to the patient. Once the body’s internal balance has been set in a lactate analysis picture, gradual withdrawal from the long-term rehabilitation plan could then be laid out. Recent medical analyses have confirmed stable pain-free and movement-limited conditions for patients for at least 10 years after they had been rehabilitated and their long-term planned rehabilitation ended.

Degenerative changes of the spine as a disease of civilization could have been treated by standard medical or nonmedical treatment but never eliminated [5, 20]. A new type of treatment in the practice of physical therapy is the Impedance Therapy method.

Conflict of interest

The authors declare no conflict of interest.