What is Clinical Neurodynamics?
Clinical Neurodynamics is a system of evaluating and treating nerve tension and restrictions. It makes use of the fact that the nervous system is intricately connected throughout the body, with attachments at all ends. Nerves attach to connective tissue within the central nervous system via meninges. They also have attachments into peripheral tissues such as skin, muscles, bones and fascia. With knowledge of how to isolate and place tension on specific nerves, diagnosing and treating can become more specific.
How it Works
In order to accommodate for the body’s natural movements, the nervous system itself has mechanisms allowing it to be mobile. First, nerves are capable of elongating, this especially takes place on the convex side of joint movement. Once nerves become lengthened, they eventually develop tension. At the end ranges of a stretch, once tensioned, nerves are capable of sliding through adjacent tissues. This sliding component is essential, as it serves to dissipate tension in the nervous system.
A common example is the straight leg raise, in which the sciatic nerve becomes elongated. Once the nerve is fully tensioned, adding dorsiflexion of the foot will move the lumbosacral nerve roots in a caudal direction. This final dorsiflexion of the foot creates the sliding component of the nerves far from where the movement was applied. Finally, adding neck flexion, as in the slump test, will create a fully tensioned state at the nerve roots by moving the spinal cord in a cephalad direction.
The mechanism previously described is not limited to the sciatic nerve and the straight leg raise or slump test. Neurodynamics makes use of this concept and applies the principles to many nerves and body regions. Just a few examples being the femoral nerve in the lower extremity and median, ulnar and radial nerve in the upper extremity. By moving the extremities in a particular sequence, tension can be applied to specific nerves. Once a nerve has been tensioned correctly, small passive movements can be used to slide neural tissues at sites far from where the force was applied. This is useful for testing and diagnosing as well as in the application of treatment.
Another example of this process is the median neurodynamic test. If the elbow is bent and shoulder relaxed, wrist movement will not greatly influence the brachial plexus. However, if the scapulae is depressed, shoulder abducted, and the elbow fully extended with forearm supination, forces will be transmitted to the plexus with only a small amount of wrist extension. With an understanding of how to safely create tension, nerves can be moved in an area in question without moving the muscular skeletal tissues in the same region.
When to Use Clinical Neurodynamics
This information is most helpful in dealing with conditions that involve an issue with the nerves. In particular when there is excessive nerve tension and or if a nerve has lost its ability to slide through adjacent tissues (pinched nerve).
With neural tension, or abnormal sensitivity to being tensioned, a range of symptoms occur. This can be aches and pains to pins and needles or even dysesthesia. These symptoms will be especially noticeable during daily movements, e.g. “putting on my socks and shoes”. A very similar clinical picture is seen with nerve sliding dysfunctions.
Traditional treatments such as anti-inflammatory medication and possibly spinal traction are still applicable. However, neurodynamic techniques can additionally be utilized to discover specific sites of entrapment or tension. Also, treatments such as nerve sliders are a safer and more effective option than traditional stretches for these conditions.
This involves moving an extremity in a particular sequence, in order to place tension at one end of the nervous system. Simultaneously, the other end of the nervous system is moved in a way that minimize tension i.e. creates slack. These movements are performed back and forth, several times, never holding longer than a few seconds. This allows the nerve to slide and avoid any sustained tension. Additionally, it is suspected that this technique may milk the nerve of inflammatory exudate and produce increased venous blood flow and oxygenation into the irritated nerve.
A Final Consideration
It is also recommended to remove joint and or myofascial restrictions before performing these techniques. This makes a well trained chiropractor an ideal physician to work with these conditions. Spinal manipulation and myofascial release, applied in the correct areas, can be excellent therapies to make for more successful neurodynamic nerve mobilizations.