Effects of Neural Tension Versus Neural Sliding Technique on Pain, Cervical Muscle Endurance and Hand Grip Strength in Unilateral Cervical Radiculopathy

Cervical radiculopathy also known as "pinched nerve", is a neurological condition caused by compression of the cervical spine nerve and roots. It is basically a lower motor neuron and sensory demonstration of neurological dysfunction of the involved cervical nerve root. Cervical radiculopathy is most commonly caused by the herniation of the cervical spine intervertebral disc or any space-occupying lesion that may lead to nerve root inflammation or impingement. Other common causes of cervical radiculopathy are spondylosis, trauma, osteoporosis, cervical instability, and sometimes oncological issues. Such problems either directly compress the cervical nerve roots or narrow the space of the vertebral foramen from where the cervical nerve root emerges which leads to neuritis, hypoxia, ischemia, fibrosis, edema, or decreased nerve mobility. Cervical radiculopathy has an average annual incident rate of 83 per 100,000 of the population with an increased prevalence in the fourth and fifth decade of life.

According to studies, the most commonly affected cervical nerve root is C7 followed by the C6 and C8. The clinical manifestation of cervical radiculopathy is quite broad involving motor and sensory changes in the upper extremity. Patients with cervical radiculopathy usually experience loss of sensation, tingling, numbness, motor defects in the neck and sometimes in the scapula, and pain in the arm and hand along the pathway of the nerve depending upon the location of the affected nerve root. The pain can be radiated both bilaterally and unilaterally into the arms, however, the prevalence of bilateral cervical radiculopathy is only 5 - 36%.

The symptoms of muscle weakness in the upper limb are often seen in patients with cervical radiculopathy. According to the principles of the kinetic chain, the upper limb is an integrated system consisting of different segments working together to accomplish the activities of daily living. In simpler words, the muscle weakness produced in any segment of the upper limb would result in generalized muscle weakness and ultimately decreased hand grip strength. To perform functional activities of daily living it is very important to maintain the grip strength of the upper extremity. But, to achieve the maximum grip strength the physical and physiological properties of nerve tissues need to be intact. Since reduced grip strength is often seen in patients with cervical radiculopathy, it becomes essential to administer an appropriate technique to rehabilitate its strength

Manual therapy techniques are considered effective in the treatment of cervical radiculopathy. Neurodynamic mobilization has been considered effective as a conservative management approach for the treatment of upper quadrant pain. It restores homeostasis in and around the neural tissues by improving the mechanical and neurophysiological integrity of the peripheral nerves, thus reducing pain and disability. Slider and tensioner are the two most commonly used neural mobilization techniques and a biomechanical distinction can be made between these two techniques. Neural mobilization plays an important role in returning to normal functional activities by restoring the range of motion and extensibility of the nervous system

Neurodynamic mobilization restores the neural tissues' ability to resist tension and stress by promoting the restoration of normal physiological function, decreasing pain, and improving function. The slider neurodynamic mobilization causes sliding movement in the neural tissue in correspondence to the nearby structures; distributing the compression and tension along the entire nervous instead of one particular region. On the other hand, tensioner neurodynamic mobilization causes tension in the neural tissue without surpassing the tissue elastic capacity that enhances nerve's viscoelastic properties. This procedure is done by taking the nerve, in the end, range of movement (elongated position), maintaining the position for a short duration, and then fully releasing the tension.