Back Pain Diagnosis
Back pain is very hard to diagnose beyond what appears to be the obvious: you have a pain in your back which may have resulted from lifting, an accident, sitting in a poor position or for reasons unclear. The main distinction which spinal surgeons make is between serious conditions, specific back pain conditions and non specific low back pain.
Non-specific Low Back Pain
This is the most common group of people with back pain. The pain may be rare or mild or can be constant or severe or come on in episodes every so often. The typical pattern is for there to be an initial episode which 50% of people can relate to a specific aggravating activity such as lifting. This is acute back pain and can be quite severe and disabling for a few days but with painkillers, some rest and getting going again it settles down and the person returns to normal activity without any restrictions.
Most people manage their episodes of acute back pain themselves as they instinctively realise that there is nothing seriously amiss and just get on with things. If however the pain is extremely severe or there are other worrying symptoms it may be worth getting advice from a doctor.
A typical examination will cover your medical history, your previous back pain history if you have one, as the clearest predictor of having back pain is having had some in the past, and the history of the present episode. The area of the pain and its severity and type (back pain symptoms), what makes it worse and better, all these things will be asked so that a picture can be built up of the type of back pain you have.
Examination will typically show limited movement with pain in the spine but little else of concern, allowing the examiner to be confident that the diagnosis is indeed non-specific low back pain.
Lower back pain can be mild and go off quickly with the person returning to normal or it can be severe and disabling and significantly reduce a person's independence.
Serious Back Pain Causes
Serious back pain causes are rare but important to identify so that the patient can be quickly referred on to an appropriate medical specialist. The main conditions which can present as back pain are kidney problems, tumours, infections, fractures and inflammatory diseases.
There are signs and symptoms (called red flags) which have to be more carefully looked at in case there is a rare chance of a serious condition causing the back pain, these include:
Cancer and infection risks:
Cauda Equina Syndrome risks:
Arthritic disease risks:
The most important aspect of screening for red flags is a routine and complete enquiry which can take a very few minutes, along with a thorough examination to discover any unusual or unexpected findings.
The Need for Investigations and Tests
Most low back pain episodes do not need any investigation as the diagnosis will be clear from the history and examination and your doctor will feel secure that there is nothing serious amiss. Tests may actually be harmful as they may introduce delays and come up with problems in the spine that do not have any relevance.
Treatment guidelines in the UK recommend against x-raying or scanning unless there is a suspicion of some serious condition. Red flags will indicate that futher investigation should be performed either by the GP or by a spinal specialist.
Specific Causes of Back Pain
Specific causes of back pain are well recognised as particular patterns of symptoms which fit together. The most obvious are nerve root compression (sciatica in the leg) and spinal stenosis in older people.
If a specific cause of back pain is suspected then the spinal surgeon is likely to refer the patient for an MRI scan or other investigation to back up the initial diagnosis and allow him or her to proceed confidently with the treatment.
Nerve Root Compression
Nerve root compression can occur in any of the spinal nerves but is most common in affecting one of the leg nerves, S1, L5 or L4 and less common but still occurring in the arm nerves where it is related to neck pain.
Nerve root compression is most commonly caused by a posterior and lateral disc prolapse with contacts the nerve root just as it is exiting the spinal canal. Compression itself is not typically enough to cause pain and so it is thought that chemical factors and restriction of blood supply in the nerve root may be important in pain production.
Sciatica symptoms are a severe pain in the buttock, thigh, calf and foot, although there may also be back pain or any of the other pain areas absent. The pain is severe, surging and often worst below the knee and in the foot. Patients are very clear about where the pain is, in contrast to referred pain from back problems where the pain distribution is much more vague.
The history may show a history of back pain for some years and then a sudden onset of awful leg pain after a stressful activity such as sitting too long or lifting. Examination is limited due to the pain produced in the patient but may find reflex loss, loss of muscle power, loss of sensibility to and sensitivity of the nerve root to even minor stretch.
These changes are all due to the conduction of the nerve root being impaired by the compression and the irritable nerve reacts badly to any tension applied to it.
Spinal stenosis is a syndrome (collection of symptoms which fit together to mean something) which occurs most commonly in elderly people, over 65 years of age.
The spinal canal is the main route down through the vertebrae that the spinal cord takes to allow its nerves to exit at their appropriate levels. In some people this canal is smaller than normal and more awkwardly shaped and they are more likely to have stenotic problems.
As degenerative changes occur in the spine a number of these impact on the space available in the spinal canal. The discs narrow and bulge backwards, the facets joints enlarge as they become arthritic and take up more space and the ligaments fold in as the spaces between the vertebrae become smaller.
The narrowing of the spinal canal limits the blood supply of the spinal cord by compressing it and can give a number of symptoms:
It is common for examination of a person with spinal stenosis to show little of importance apart from an inability to extend the spine (lean back) due to the arthritic changes in the facet joints. Management depends on how limiting the symptoms are and decompression via operation can be very successful.
Facet Joint Syndrome and Degenerative Disc Disease
Many clinicians recognise these two syndromes – facet joint arthritis which limits backwards bending and gives pain on standing, walking and sitting, and degenerative disc disease which can give signficant back pain along with referred leg symptoms.
Both these syndromes are much harder to pin down with objective findings and are subject to the clinical opinion of the person who sees the patient so are much less scientifically valid than the previous two.
Further information: back pain
As it is difficult to get accurate information about your episode of back pain it can be useful to follow a back pain blog as this will be written by someone with real experience of what you are going through. This can turn up good tips for managing pain and getting help.