Effects of Exercises and Electrical Current Application Aiming to Strengthen Neck and Shoulder Blades Muscles on Symptoms of a Pinched Nerve in the Neck

Cervical Radiculopathy (CR) is an objective loss of sensory and/or motor function as a result of conduction block in axons of a spinal nerve or its roots due to compression or irritation of the cervical spinal nerve root . Etiology is attributed to cervical foraminal compression in 70-75 % of cases due to anterior and posterior degenerative changes of the zygapophyseal joints, cervical spondylosis and reduction in disc height. The most common clinical manifestations of CR include sensory impairments (e.g. paresthesia), motor abnormalities (e.g. muscle weakness) and neck pain radiating to the arm.

It is a common diagnosis, incidence of which ranged between 0.832 - 1.79 per 1,000 person, and prevalence values ranged from 1.21 - 5.8 per 1,000 according to the latest epidemiological studies.

The incidence of neck pain was found to be high in college students: 48%-78%. What is more, the annual growth rate of cervical spondylosis in college students was twice that of the 50-year-old participants. A high incidence of neck pain among college students was associated with a heavy academic workload and the pressure of examinations, which may lead to the deformation of the neck and shoulders, as well as soft tissue damage.

In the meta-analysis of the college grade differences on neck pain in 2287 college students, it was shown that a higher probability and frequency of neck pain occurred at senior grade level. As can be seen from the review of existing literature, based on the incidence of neck pain, the potential of developing cervical radiculopathy is increasing at a younger age than was previously believed, with the peak age being 50 to 54 years. If left untreated, CR could lead to future disability and persistent functional impairments due to neural inflammation and edema, hypoxia and ischemia of structures.

However, despite the severity of the condition and the rapid incidence growth rate, there is still a lack of evidence in the area of conservative treatment, i.e. physiotherapy options. In previous studies, Electrical Muscle Stimulation (EMS) had no significant impact on pain relief, disability and patient satisfaction when used as an adjunct to cervical mobilization and manipulation, at post treatment, short-term and intermediate-term follow-up. Moreover, exercise treatment (ET) also consists of various interventions and is typically combined with drugs and other treatments, which make it difficult to determine the effects of a single intervention.

Nevertheless, results of more recent studies, are favoring application of EMS on various muscle groups, for example it was stated that EMS has significant effect on muscle strength of quadriceps and trunk extensors, similar results were also observed in the study assessing effects of EMS on upper extremity strength. Moreover, it was shown that neuromuscular electrical stimulation (NMES) induced a decrease of cortical activation during execution of hand movements, which indicates that application of NMES can increase the efficiency of the cerebral cortex during execution of motor tasks.

One should also consider that in the recent systematic review solitary ET directed on strengthening deep cervical flexors, scapulo - thoracic and upper extremity muscles had beneficial effect on pain and function at immediate post treatment and up to long-term follow-up. Moreover, strong evidence was found for effectiveness of deep cervical flexors (DCF) training on neuromuscular coordination of the neck, because it reduces the overactivation of the superficial muscles and improves the activation pattern of the cervical muscles.

It is also worth mentioning that, compared with the healthy adults, the individuals with CR have significantly smaller anterior displacements of the centers of mass and pressure, reduced muscle activity of the upper trapezius, sternocleidomastoid and splenius capitis muscles in response to all postural perturbations. Those findings are indicative of altered neural control of the neck musculature, leaving the cervical spine vulnerable to reactive forces.

Thus, physical therapy options for conservative management of CR should mainly focus on improving muscle function and neuromuscular control of the neck.

Given the promising results of EMS and ET, it is worth to investigate both in terms of neck muscle function. Thus, this research will try to do that.

Looking at the existing literature, training based on electrical muscle stimulation and voluntary muscle contraction has positive effects on muscle strength of various muscle groups, when applied in superimposition due to facilitation of additional muscle fibers recruitment.

However, superimposition of electrical stimulation on exercise was not assessed in the context of CR patients, who present with incomplete central activation levels and could favor from this kind of treatment, in terms of improving motor control. Additionally, restoring muscle balance in cervico - scapular region, adds to the proper neutral alignment of the cervical vertebrae, leading to increased intervertebral foraminal area, decreased nerve root compression and relieve of cervical radiculopathy symptoms.

Thus, the proposed study is aimed to investigate the effects of exercise therapy with electrical muscle stimulation and just exercise on cervical muscle function. Secondly, compare the effects of both therapy options. Lastly, see if improvement of neck muscle function would have and impact on cervical radiculopathy symptoms, in terms of pain and motor deficits.

Inclusion criteria

• Student must be enrolled in the last 2 years of Bachelor degree or in Master's degree in one of the healthcare - related programs at the European University of Lefke;
• Age 18 - 29 years old;
• Neck pain of minimum 4 or more on numerical rating scale (0 - 10);
• Duration of symptoms 3 < months < 6, i.e. subacute symptoms with chronic/stable presentation;
• Has 1 or more of the following symptoms: paresthesia of 1 or both upper extremities at the level below elbow; pain radiating from neck to shoulder/arm/below elbow; feeling of weakness in 1 or both of the upper extremities, stiffness and/or tenderness and/or hyperalgesia in the cervical and/or upper thoracic area;
• Obtained "Cervical Radiculopathy" diagnosis from a physician, according to neurological examination findings: Positive cervical radiculopathy specific provocative tests (Spurling's Maneuver, Upper Limb Tension Test; Reduced Deep Tendon Reflexes of brachioradialis, biceps and triceps.

Exclusion criteria

• Any recent head/neck or shoulder trauma in the last 3 months;
• Received physiotherapy for neck - related complaints in the last 3 months;
• Received or currently receiving any kind of pharmacological intervention (muscle relaxants, NSAIDs, corticosteroids injections) in the last 3 months;
• Presents with symptoms favoring shoulder pathology: pain localized at the shoulder that worsens at night, positive Drop Arm Test, pain referral patterns are localized in the upper arm above elbow;
• Any recent surgeries to the neck, upper extremities within the last 6 months;
• Any diagnosed neurologic or musculoskeletal conditions that could mimic cervical radiculopathy, i.e. peripheral neuropathies of different origin, thoracic outlet syndrome medial/lateral epicondylitis, myofascial pain syndrome, etc.;
• Any cardiovascular (recent DVT, congestive heart failure), metabolic (diabetic polyneuropathy), neurologic (impaired consciousness, epilepsy), malignant conditions in which application of electrotherapy or exercises imposes risk on the patient;
• Presence of pregnancy;
• Active implants, e.g. cardiac pacemaker;
• Any skin lesions in the cervical and/or scapular region, i.e. infections, open - wounds;
• Refuses to participate in the study.