The detection of serious spinal pathology

Serious spinal pathology accounts for less than 1% of all back pain. Serious pathology is rare, but one of our most important jobs is to detect it or to

Box 2,4 General neurologic examination when there is a question of widespread neurology

» Brief sensory testing of the arms, the trunk dermatomes, and the saddle area

• Palpate the bladder

• Upper motor neurone signs in the legs include increased muscle tone, brisk reflexes, clonus, upgoing plantar reflexes, loss of position sense in the toes and loss of coordination in the heel-shin test exclude it and reassure the patient. Indeed, some patients say this is their only reason for coming to see a doctor. If we can assure them there is nothing serious, then they can deal with their backache themselves. That depends on confident reassurance. Bringing the patient back "to check" raises doubt that you are not sure or, worse, that there may be something serious you are hiding. All we need at this point is a simple yet reliable screen to decide if there is any risk of serious spinal pathology- Diagnosis of the pathology can come later. Triage simply decides if there is a need for further investigation and referral, or if we can rule out serious spinal pathology.

Most backache affects the lower back or neck. It varies with time and physical activity. It presents in the early to middle years of adult life. It does not affect general health. Serious spinal pathology presents the opposite features. In our series of 900 patients, we found that a few key features detected all 73 patients with serious spinal pathology. Deyo et al (1992) produced a similar list. AHCPR (1994) and RCGP (1999) called these "red flags" for possible serious spinal pathology (Box 2.3).

The concepts of triage and red flags seem to have caught people's imagination and helped to sell this approach.

Most backache presents in the early or middle years of adult life. Patients who present for health care before the age of 20 are more likely to have serious pathology or a structural problem such as spondylolisthesis. Patients who develop new or different back pain after the age of 55 are more likely to have serious pathology, particularly spinal metastases or osteoporosis.

Non-mechanical back pain

Ordinary backache is mechanical in the sense that it varies with physical activity. Certain postures or movements may make the pain worse. A comfortable position, change of position, stretching, or certain exercises may make the pain better. The pain varies over the course of the day or weeks in response to different activities or treatment.

In contrast, non-mechanical back pain is unrelated to time or activity. It may start spontaneously and gradually. It often becomes gradually worse. Rest or exercises do not relieve it and the patient may not be able to f ind any position of comfort. Pain may be worse in bed at night when the patient has no distractions.

Thoracic pain

Most mechanical problems affect the lower back or the neck. Pain in the thoracic spine or between the shoulder blades is less common but when it does occur is more likely to be due to serious pathology. In our selected series, 30% of patients referred to hospital with thoracic pain had either spinal pathology or osteoporotic collapse of a vertebra.

Violent trauma

Only violent trauma, such as a fall from a height or a road traffic accident, is likely to fracture the normal spine. Postmenopausal women with osteoporosis or patients on systemic steroids may suffer collapsed vertebrae as a result of more minor injury.

Previous medical history

Many systemic diseases can affect the back. A history of carcinoma is most important, however long ago. A history of rheumatologic disorders, tuberculosis, and any recent infection may be relevant. Drug abuse, immune suppression and human immunodeficiency virus (HIV) may predispose to infection. Systemic steroids may cause osteoporosis.

Systemic symptoms

Patients with ordinary backache are generally healthy. If a patient with back pain is unwell, there is more likely to be some serious disease. The most significant symptom is weight loss. General malaise, fever, or simple clinical impression may all raise suspicion. However, many patients with a spinal infection do not have fever, so the absence of fever does not exclude infection. If the clinical history raises your suspicions, your examination should include the common tumor sites - thyroid, breasts, lymph nodes, abdomen, and prostate. You may also order urine testing, an erythrocyte sedimentation rate (HSR), and a chest X-ray.

Limited lumbar flexion

Clinical examination of the spine is not very good for detecting spinal pathology, apart from major spinal deformities and widespread neurologic disorders. So a normal examination does not exclude serious pathology, particularly metastases.

The most important physical sign in the back itself is persistent severe restriction of lumbar flexion. In our series, 50% of patients with limited lumbar flexion had either serious spinal pathology or an acute disk prolapse. Lumbar flexion was severely restricted in 707» of patients with spinal infection. However, flexion was normal in 30% of patients with spinal infection, in 81% with inflammatory disease, and in 91% with spinal metastases. Spinal pathology can be present in the thoracic spine without any restriction of lumbar movement. Remember that a normal physical exam does not exclude serious spinal pathology.

We must also improve how we measure lumbar flexion. How close you can reach towards your toes does not test spinal movement, but depends on a combination of lumbar and hip flexion, hamstring tightness, and motivation. Some patients with ankylosing spondylitis and a fused lumbar spine can still touch their toes (Fig. 2.3). So if we want to measure spinal movement we must measure the back itself. The simplest method is the Schober technique. Make two marks on the skin and see how much they move apart as the patient bends forward (Fig. 2.4). This gives a reliable measure of lumbar flexion. We will discuss more precise

Prader Willi Syndrom
Figure 2.3 The distance from the fingers to the ground does not measure lumbar flexion. Look at the shadow on the wall showing no loss of lumbar lordosis in this patient with ankylosing spondylitis.

methods using an inclinometer when we look at the evaluation of physical impairment in Chapter 8, but this simple method is sufficient for routine clinical use.

Summary: possible serious spinal pathology

• The most important screen for serious spinal pathology is a careful clinical history of red flags.

• A normal physical exam does not exclude serious spinal pathology.

• A normal X-ray does not rule out spinal pathology.

Triage is based on red flags, but the problem is that individual red flags are not very accurate for diagnosing pathology (van den Hoogen et al 1995). There are too many false-negatives and false-positives. So it is a question of clinical judgment,

Figure 2.4 The Schober technique of measuring lumbar flexion. Make a mark at the level of the dimples of Venus, which approximates to the lumbosacral junction. Make a second mark 10cm higher, and a third mark 5cm lower. Ask patients to reach down as far as they can towards their toes, and measure the increase in the distance between the top and bottom marks. The normal is at least 5 cm. From Waddell (1982), with permission.

Lumbar Flexion Schober

Figure 2.4 The Schober technique of measuring lumbar flexion. Make a mark at the level of the dimples of Venus, which approximates to the lumbosacral junction. Make a second mark 10cm higher, and a third mark 5cm lower. Ask patients to reach down as far as they can towards their toes, and measure the increase in the distance between the top and bottom marks. The normal is at least 5 cm. From Waddell (1982), with permission.

combining all the clinical features. If there are no red flags on careful clinical assessment, you can be 99% confident that you have not missed any serious spinal pathology. If there are some red flags, it still depends on clinical judgment. With typical, mechanical low back pain after a minor lifting injury in an 18-year-old, it would be reasonable to wait and see how the patient gets on before considering any referral or investigation. A 60-year-old who presents with several months' gradual onset of new thoracic pain and weight loss needs urgent investigation, even if clinical exam and plain X-rays are completely normal.

The aim of triage is to decide if there is any question of possible serious spinal pathology. Exact diagnosis will come later. Triage is only to decide which patients need further investigation.

Back Pain Revealed

Back Pain Revealed

Tired Having Back Pains All The Time, But You Choose To Ignore It? Every year millions of people see their lives and favorite activities limited by back pain. They forego activities they once loved because of it and in some cases may not even be able to perform their job as well as they once could due to back pain.

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