The Human Neck-Part Two
Posted: Thursday, June 25, 2009
by Jonathan Blood Smyth
Easily inflamed and very reactive to both unusual or in time to normal stresses on the neck, the facet joints generate symptoms in a variety of areas. Local tender areas and more widespread aching can occur in the upper arm, shoulder blade and shoulder areas and in the neck itself. As a reaction to this pain, spasm can develop in the neck musculature which adds to the overall problem by further compression of the joints and thereby increased pain and joint pressure. This spasm can become very severe and shows as hardness and tightness in the neck muscles which can be easily felt.
A lack of thoracic kyphosis can mean that the thoracic spine approaches its junction with the cervical spine above it in too vertical a position, forcing the neck to adopt a correspondingly more vertical posture than normal. The loads the neck bears are usually spread between the discs and the facet joints by the normal lordosis and if this is lost then increased loads may be thrown onto the discs, causing increased degenerative changes within them. The opposite, where an increased thoracic curve forces a correspondingly increased neck curve, is countered either by neck or lumbar extension.
With the poking neck syndrome occurring with an increased level of thoracic and cervical curves, the head is placed well forward of its support in the neck, forcing the main neck extensor muscles to over work to maintain their hold on head posture. The overuse of the upper trapezius muscles can cause trigger points to develop in the muscles, causing local and referred pain problems which can be very persistent. The overactivity of the upper part of the trapezius can cause a corresponding inhibition of the activity of the lower trapezius muscle which stabilises the scapula, enabling a good pattern of control for arm movement.
Our necks can be injured in a series of different methods, either suffering sideways forces involving twisting or shearing or longitudinal compression forces, or both. The outer disc walls are vulnerable to such injuries and so begins the sequence of degenerative events in the disc, the pain itself followed by both inhibition and overwork of the muscles, loss of range of motion and limitation of disc nutrition. Pain worsening leads to the extensor muscles of the neck increasing the vertical pressures by over contracting, pushing the vertebral levels together more closely. Segmental disc narrowing may lead to stiffness but can also cause hypermobility of the segments as the disc, having lost water content and ligamentous integrity, loses its role in stability.
Segmental degeneration is often accompanied with time by the growth of osteophytes, outgrowths of bone, which sprout from the edges of the abnormal segment. An abnormally moving segment is likely to suffer this change and this may be an attempt by the bodys systems to improve the stability of the segment by splinting it with bone along the soft tissues nearby. The nerve roots exit from the intervertebral foramens each side of the spine and there are vulnerable to impingement at times by osteophytic outgrowth, causing severe nerve root pain in the arm. Surgical management of such impingement may be required in some people but overall this condition is not amenable to surgery.
The facet joints of the neck are now vulnerable once the affected segment has stiffened with degenerative changes. Narrowing of the discs causes the facet surfaces to suffer increased contact forces as the segment closes down on itself. The movements which should be performed by the gradually more abnormal and stiff facet are passed onwards to other parts of the spinal system above or below the stiff segment. Facet joints which are normal can then start to suffer from the abnormal forces and change.
Jonathan Blood Smyth, editor of the Physiotherapy Site, writes articles about Physiotherapists, physiotherapy, physiotherapists in Birmingham, back pain, orthopaedic conditions, neck pain and injury management. Jonathan is a superintendant physiotherapist at an NHS hospital in the South-West of the UK.
This Article has been viewed 241 times. (Not updated in real-time.)
No comments yet.We want your comments! If you can read this, you don't have javascript enabled, so you can't use this comment system. Please enable javascript.