Rodin U.A., Ushakov A.A.
Academician N.N. Burdenko central military clinical hospital
Moscow, Russia

All musculoskeletal system and peripheral nervous system diseases and traumatic injuries in acute period are characterized by acute pain, edema, soft tissues hemorrhage, extravasations and infusions into joint cavity, inflammatory reaction and dysfunction. Analgesics use doesn’t always resolve the problem of acute pain syndrome stop.

Last few years new low-frequency electro therapy method – dynamic electroneurostimulation method – is implemented; it has clearly defined analgesic, antiedema, anti-inflammatory, and vasoactive influence.

DENS is method of impact on coverlet receptor system, on biologically active points, on sensitive afferent conductors in pain zones by very short-termed (400 mcs) neuron-like (bipolar) electrical impulses of low frequency (10 to 200 Hz) and low intensity (on average 200 to 400 mcA).

Duration and frequency of current pulses used for DENS are comparable with frequency and duration of pulses in thick myelinated afferent fibers having big velocity of pulsation. Thanks to flow of rhythm regulated afferent electric pulsation created during the procedure neurons of posterior horns substantia gelatinosa are stimulated, and their perception of nocigenic (pain) information coming from pathology center through thing non-myelinated nervous fibers with low velocity of pulses conducting is blocked.

Analgetic structures neurons activation is accompanied with supraspinal system stimulation and discharge of endorphins by putamen, by digestive apparatus, endocrine glands; the result is pain pulsation inhibition. Acute pain weakening and, to a lesser degree, chronic pain weakening is marked already during the procedure and then is kept during 1 to 2 hours after the procedure.

Appearing as an answer on rhythmic stimulation the coverlet muscles and skin arteriole unstriped muscle fibrillation activates destruction process of algogenic substances (bradykinin) and mediators (acetylcholine, histamine) in pain center. Besides, analgesic effect from DENS is also related to local blood-flow enforcement, and trophy activation that remove perineural edema and thus have pathogenetic influence on reason of the pain syndrome.

Besides the analgesia appearing during the procedure, as a result of clear
vasoactive effect blood circulation in ischemic tissues intensifies, metabolic and trophic
processes in impact zone and deeply located tissues segmental connected with
corresponding skin areas. Because of local, segmental and general organism reactions its
regulatory systems synchronization is reached. Stimulating impulses have regulative
influence on organism, mobilize reserve functional tissue elements and recover disturbed
functions, help to switch rapidly the humoral and immune mechanism, remove energy and
information block, and restore lost links between pathologic zones and all control systems
of the organism.

During DENS following medical effects are clearly defined: analgesic, anti-edema,
anti-inflammatory, trophic, resolving, metabolism stimulating, stimulating regenerative
process of trophic ulcer and weakly healing injuries, normalizing hormone state, and
immunomodulating.

After the DENS application for treatment of musculoskeletal and nervous system
diseases and injuries for 2 to 4 hours pronounced analgesic effect appears. Repeated
application of 3-4 procedures a day during several days may completely remove acute
pain syndrome or, as a last resort, effectively reinforce analgesic and anti-inflammatory
preparations influence, contribute to lost function recover.

Repeated application during 24 hours of the DENS method is allowed because of
low intensity of impulse electric current. The method is easily transmitted by patients and
having injuries of different severity degree, older people and children. The method
application is not contra-indicated when there is Ilisarov’s apparatus on fracture,
intraosteal or on-bone osteosynthesis. During impact of low frequency and intensity
impulse, generated by DENS apparatuses on metal implants electrolysis products in the
amount that can evoke cauterizing effect (chemical injury) next to metal foreign element
don’t form.

During several years home industry produces apparatuses for dynamic
electroneurostimulation of “DENAS” and “DiaDENS” models. Apparatuses are made in
several modifications, and widely used in clinics and at home. The apparatuses are
portable and electrically safe.

The more interesting model for us is “DiaDENS-PC”. The apparatus lets conduct
“testing” – diagnostic investigation of skin ohm resistance and identify pain zones and
zones of “latent pain”. The testing conducted before and after the procedure, at the
beginning and in the end of treatment course, is objective method of conducted treatment
efficiency control.

In the apparatus frequency range is widened from 1 Hz to 200 Hz, that allows
DENS method use in case of acute pain (140 and 200 Hz frequencies), chronic pain
syndrome (60 and 77 Hz frequencies), have regulative effect on tone of unstriped muscles
of blood vessel and lymphatic and internal (10 Hz frequency). “DiaDENS-PC” model has a
regime of frequency modulation “77 10”. Output for external punctual electrode connection
is provided for electro puncture (reflex therapy) and diagnostic by Voll conduction. Besides
there is an output for paraorbital electrode connection to impact on skin receptor system
around eyes.

During period from 2003 to 2006 287 patients aged from 28 to 68 with
musculoskeletal and nervous system diseases and traumatic injuries were under our
observation.

In cases of contusion, sprain, and rupture of joint-ligament apparatus and joint
meniscus injuries (27 persons) after intensive DENS therapy during 10-14 days
hemorrhage dissolved, soft tissues edema and joint coats irritation (synovitis) disappeared,
pain syndrome significantly regressed, and joint and extremity function restored. Pain
syndrome regress, hemorrhage dissolving, and function restoration began 5-7 days faster
than similar traumatic injuries in persons who didn’t get DENS and other physiotherapeutic
methods.

In case of open and simple long bones fractures (47 persons) DENS was
combined with exercise therapy. Rehabilitation period reduced on average for 5 days in
comparison with patients of similar group who didn’t get DENS within complex treatment.
Good results were got in 87% of patients, satisfactory – in 13%. There were not negative
results.

Group of patients with joint diseases was formed of people with deforming
arthrosis of big joints, with gouty and psoriatic arthritis (58 persons). Good DENS efficiency
was got in 76% of patients, satisfactory – in 24%. Negative results of the DENS application
were not marked.

The larger group got DENS were patients with spinal degenerative injuries (129
persons). After the DENS method course treatment, including “DiaDENS-PC”, in 75% of
patients with dorsopatia there was a good therapeutic effect, appearing in acute pain
syndrome regression, muscle-tone syndrome liquidation, spine and injured nerve function
improvement and blood circulation in vertebral arteries improvement. In 19.1% of cases
there was satisfactory result, when pain and muscle-tone syndrome intensity significantly
reduced, but didn’t disappear. In complex treatment of such patients other
physiotherapeutic methods were included. 5,3% of patients haven’t got noticeable effect.

This group included patients with spinal discogenic injuries when herniations of
intervertebral disks in neck zone were, according to MRT, 4 mm, and in lumbosacral zone
– 8-12 mm.
The rest group included patients with traumatic compressive-ischemic plexopatia
of upper and lower extremity (12 per.), traumatic vertebrogenic neuropathy of median
nerve (8 per.), polyneuropathy of viral aeteology (shingles) – 6 persons. In all cases good
clinical effect was got that exceeded treatment results of patients who didn’t get DENS.

Summary:

1. DENS application for treatment musculoskeletal and peripheral nervous
systems diseases is highly effective physiotherapeutic method.
2. “DiaDENS-PC” model is a multifunctional device allowing conducting an
assessment of organism systems functional state and therapy in different medicine areas.
The device has good design; it is electrically safe, simple and comfortable in use.
3. DENS may be recommended for application in wide clinical practice by doctors
of different specialties as effective method of analgesia by urgent indication, and for use
DENS method by patients at home after consultation with physiotherapist.