Nerve Root Impingement

This is a term that is used by some to cover all conditions that affect the nerve and cause radiating symptoms into the limb (arm or leg) or around the chest wall. However I would suggest that it becomes too generalised when used in this manner. We are becoming progressively more capable of making more accurate and specific diagnosis of what structural problem is to be the cause. Many of these conditions that cause radiating symptoms are covered in more detail and include the prolapsed disc, slipped disc or stenosis.

For me Nerve Root Impingement refers to the impinging of a spinal nerve at its oulet. Anything that narrows the oulet space, called the foramen, leaves the exiting nerve with less space to exist in (essentially producing a form of foraminal stenosis).

Many things impact on this foraminal space. For instance the normal changes of wear and tear result in narrowing of the disc and often some associated bulging of the disc wall, hypertrophy (thickening) of the local ligaments, hypertrophy (thickening) of the local bony structures, and often the development of bony spurs known as osteophytes. All these normal changes have the potential to reduce the size of the foraminal outlet as does the development of a cyst or some other space occupying lesion.

In essence the nerve root can sometimes become impinged within the narrowed outlet. The presentation of symptoms will be quite predictable. Movements that cause further narrowing of the foraminal outlet on the affected side eventually produce or increase symptoms once sufficient pressure is imposed on the nerve. Likewise the opposite is also true in that the opening of the foraminal outlet is likely to have a relieving effect.

Given that we all get a degree of narrowing as life goes on it is normal and the nerve will typically tolerate it well. It is only when the nerve becomes irritated, e.g. by a traumatic event or excessive pressure, will symptoms be produced.

Regardless where in the spine the same movements typically cause narrowing the foraminal outlets. These are the movements of extension (arching backwards / looking up), rotating or side bending to the spine (where narrowing occurs on the side rotating or side bending towards). Combining the various movements will alter the degree and nature of the narrowing that occurs. The provocative movements will therefore depend on the degree of irritation and / or impingement occurring.

Settling the irritation around the nerve is often sufficient to relieve symptoms. This can usually be done with appropriate exercises and short term modification in aspects of normal lifestyle that are currently provocative. The use of medication and some manual therapy techniques might also assist in resolution of symptoms. Long term self management strategies have the potential to minimise the chance of recurrence.