150 Canine Sports Medicine and Rehabilitation
in peripheral arterial disease (Williams et al.,
2017). By improving blood flow and reducing
risk of edema development, the elicited muscle
contractions help to decrease the development
of wounds commonly seen with these diagno
ses, even as effectively as intermittent pneumatic
compression (Broderick et al., 2014; Williams
et al., 2015).
Therapeutic effects on tissue flexibility
and joint ROM
In a 2016 study by Yoshimura and colleagues,
NMES was used to provide cyclic muscle twitch
contraction to immobilized rat soleus muscle
(accomplished through plaster casting for 4
weeks), resulting in substantially improved
dorsiflexion ROM as compared to immobilized
joints that did not receive NMES. Further exam
ination of the muscle tissue revealed significant
difference in the collagen composition of the
perimysium and endomysium, suggesting
that NMES use reduces the development
of immobilization‐induced muscle contracture
(Yoshimura et al., 2016).
NMES can also assist in improving mobility of
limbs affected by spasticity following stroke,
based on both decreased measures of spasticity
(Modified Ashworth Scale) and increased joint
ROM via goniometry (Stein et al., 2015). Potentially
more translatable to canine patients often seen in
rehabilitation, similar results have been found
when using NMES to address spasticity follow
ing spinal cord injury (Carty et al., 2013).
Therapeutic effects on muscle strength
NMES is most commonly used to facilitate
muscle strengthening and/or to slow disuse
atrophy. Indeed, NMES has been used to pro
mote muscle strength in human patients for
decades (Ward & Shkuratova, 2002). Studies
have shown NMES to be capable of promoting
strength gains similar to those seen with resist
ance training in healthy individuals (Pantović
et al., 2015) and that it can enhance gains when
combined with active exercise for patients with
orthopedic diagnoses such as knee osteoarthri
tis (de Oliveira Melo et al., 2016) or following
orthopedic surgeries such as anterior cruciate
ligament (ACL) reconstruction (Lepley et al.,
2015) or total knee replacement (Chughtai et al.,
2016). NMES can also lead to increased strength
in patients with significant illnesses (Roxo et al.,
2016), such as chronic heart failure (Jones et al.,
2016), chronic obstructive pulmonary disease
(COPD) (Coquart et al., 2016), and in patients
in the ICU following cardiothoracic surgery
(Fischer et al., 2016). There is some emerging
evidence that NMES may promote muscle
strengthening even in severely weakened indi
viduals such as those with myotonic dystrophy,
for whom there are otherwise very limited
strengthening options (Cudia et al., 2016).
NMES has also demonstrated efficacy in pos
tural retraining. A 2016 study showed that
trunk NMES combined with physical therapy
(neurodevelopmental therapy) led to better
improvements in upright posture and sitting
balance of children with cerebral palsy as com
pared to patients who received Kinesio Taping®
in combination with the same physical therapy
intervention (Karabay et al., 2016). Similar gains
in postural control have been observed with
trunk NMES use in adult patients following
stroke (Ko et al., 2016). Additionally, postural
balance and control can be improved through
NMES use in otherwise healthy elderly indi
viduals through targeted treatment of distal
musculature (plantarflexors) used in balance
reactions. This study and others also show that
NMES can positively impact the muscle weak
ness associated with aging (Benavent‐Caballer
et al., 2014; Mignardot et al., 2015).
Strength gains with NMES are also possible
in patients who are unwilling or unable to
actively contract target muscles (Karabay et al.,
2012, 2016). Many human and canine patients
may not be able to maximally contract a muscle
after injury or surgery. In these cases, an electri
cally induced muscle contraction can produce
greater torque—and therefore greater strength
gains—than if NMES were not used (Fitzgerald
et al., 2003). Clinically, there is evidence that
NMES use following orthopedic surgery results
in decreased muscle mass loss, increased mus
cle strength, and improved functional muscle
use (Snyder‐Mackler et al., 1991).
NMES can also be used to improve motor
control and timing (Kim et al., 2016). This is
especially useful when considering the canine
patient, who is likely unable to follow specific
verbal and tactile cues to contract a specific
muscle at the appropriate time.