Learning Bites on Back Pain ( BMJ Learning 2015)

Learning Bites on Back Pain ( BMJ Learning 2015)

Back pain affects up to a third of the adult population of the UK.

It is the second most common cause of long term absence from work in the UK after stress.

Although most patients will have non-specific low back pain or nerve root pain (sciatica), some may present with spinal pathology, such as malignancy.

If you miss an episode of spinal pathology, this can result in permanent damage to the motor nerves.

At the same time you should remember that patients with serious underlying pathologies constitute only a very small minority. The vast majority of acute back pain is self limiting and of a "non-specific" character. Whatever the cause it is important that you are able to assess and correctly manage patients who present with acute back pain.

Learning bite: classification of low back pain

The European guidelines for the management of acute non-specific low back pain classify back pain into the following1:

·  Acute low back pain - pain that lasts for less than six weeks

·  Sub acute low back pain - pain that lasts between six and 12 weeks

·  Chronic low back pain - pain that lasts more than 12 weeks.

The European guidelines also classify acute back pain into three categories. These are:

·  Serious spinal pathology

o  This includes infection, malignancy, fracture, and inflammatory causes such as ankylosing spondylitis

·  Nerve root pain

o  The sciatic nerve becomes trapped or irritated either in the lumbosacral spine or the muscles of the lower back or buttock, if they go into spasm secondary to pain

o  It may take up to two months for the patient's symptoms to resolve

·  Non-specific low back pain

o  This is back pain that is not due to either serious spinal pathology or nerve root pain

o  It is often triggered by a minor sprain or strain of the back

o  Pain may be mechanical - worsened by certain movement or postures

o  Pain usually improves within two weeks.

Learning bite: aims of treatment of acute low back pain

The aims of treatment of acute low back pain are to:

·  Relieve pain

·  Improve function

·  Prevent recurrence of pain

·  Prevent chronic pain.

Clinical tip

When you assess patients who present with back pain you should

·  Rule out serious pathology by asking about red flags

·  Ask about nerve root pain

·  Examine all patients - usually a brief examination is sufficient

·  Examine other joints close to the back such as the hip joint for pain

o  Pain can be referred from the hip joint to the back.

You should advise patients to attend for review if their symptoms are not improving within four to six weeks or if their symptoms are worsening.

At review you should reassess patients for symptoms and signs of serious spinal pathology, nerve root pain, and yellow flags.

Learning bite: back examination

The European guidelines for acute back pain advise clinicians to perform a brief examination on all patients who present with back pain. This could include:

·  Inspection of the back and spine

·  Palpation of the vertebral column, paraspinal muscles, and gluteal muscles

·  Testing for range of movement of the back

·  Examination of the hips

·  Straight leg raise and sciatic stretch test

·  Tone, power, reflexes, and sensation of the lower limbs.

Learning bite: yellow flags in patients presenting with back pain

Yellow flags in a person presenting with back pain include

·  An inappropriate perception of back pain

o  The belief that back pain is harmful and disabling

o  The belief that passive activity such as bed rest is better than staying active

·  Lack of support at home and social isolation

·  Mental health problems such as depression, anxiety, and stress

·  Problems at work such as job dissatisfaction

·  Claims for compensation and benefits.

Clinical tip

You should reassess patients who have not returned to their usual activities within four to six weeks. You should also ask about yellow flags at this time.

You can approach the subject of yellow flags by asking patients the following

·  Have you had time off work because of back pain?

·  What do you think is the cause of the back pain?

·  What do you think will help the pain?

·  How does your employer respond to your back pain?

·  Do you plan to return to work?

You can help patients who are at risk of developing chronic back pain by

·  Offering information and reassurance about acute back pain

·  Correcting misconceptions - for example that bed rest is better than staying active

·  Treating mental health problems such as depression

·  Avoiding passive treatments such as bed rest

·  Encouraging active treatment such as a gradual return to normal activities

·  Setting realistic goals

·  Offering an exercise programme to patients who have sub-acute back pain - pain that lasts between six and eight weeks

·  Consider referral to a back school

o  Back schools educate patients about back care, how to avoid back pain, and exercises that can strengthen the back. A recent Cochrane review showed that back schools in the workplace can help patients with chronic low back pain.

The availability of back schools is patchy in the UK. But services may be available that are not known as "back schools" but that offer similar services - for example "back clubs" run by professionals, local support groups, and expert patient programmes.

Learning bite: spinal cord compression

The thoracic vertebrae are a common site for compression of the spinal cord.

The general symptoms of spinal cord compression include:

·  Weakness and abnormal sensation of the lower limbs

·  Pain over the vertebrae

·  Urinary retention

·  Faecal incontinence.

The spinal cord ends at the level of the L1 and 2 vertebrae. Compression above this level causes upper motor neurone signs. These include:

·  Increased tone in the limbs

·  Hyperreflexia

·  Plantar reflexes

·  that are up going.

Cauda equina syndrome

Cauda equina syndrome is compression of the spinal cord below the level of the L2 vertebra. (The cauda equina branches off the lower end of the spinal cord and contains the nerve roots from L1-5 and S1-5.)

It causes lower motor neurone signs. These include:

·  Reduced tone in the limbs

·  Absent or reduced reflexes

·  Plantar reflexes that are down going.

This condition is a neurological emergency.

It is sometimes due to prolapse of an intervertebral disc below the level of the L2 vertebra. If you suspect that a patient has cauda equina syndrome, you should immediately refer them to a spinal surgeon. Early treatment can prevent permanent damage to the motor nerve and sphincter. You should suspect a diagnosis of cauda equina syndrome in patients with:

·  Gait disturbance and limb weakness - this is due to lower motor nerve compression

·  Urinary retention or incontinence

·  Faecal incontinence

·  Saddle anaesthesia - this is numbness of the groin, buttocks, and back of the thighs.

Clinical tip: red flags in a patient presenting with acute back pain

You should exclude serious spinal pathology such as malignancy in all patients who present with acute back pain. You can do this by asking about red flags. Patients with a history that includes positive red flags are at a higher risk of having a serious spinal pathology. Red flags in a patient presenting with acute back pain include

·  Age less than 20 or more than 55 years

·  A recent history of trauma

·  Constant progressive pain - this includes pain that is not associated with movement and not relieved by lying down

·  Thoracic pain

·  A past history of malignancy

·  Recurrent or prolonged use of corticosteroids

·  Immunosuppression and HIV

·  Substance misuse

·  Being systemically unwell

·  Unexplained weight loss

·  Neurological symptoms such as weakness of the limbs

·  Structural deformity of the spine.

NICE clinical guideline (2015) on suspected cancer

This guideline recommends that:

·  In patients with back pain and weight loss who are 60 years and over, you should also consider a possible diagnosis of pancreatic cancer and arrange an urgent direct access CT scan (to be performed within two weeks) or an urgent ultrasound if CT is not available

·  You should consider a possible diagnosis of myeloma In patients with persistent back pain who are 60 years and over. You should offer a full blood count, blood tests for calcium, and plasma viscosity or erythrocyte sedimentation rate.

Clinical tip

In addition to appropriate management of their acute problem, patients with osteoporotic compression fractures should receive calcium supplements and a bisphosphonate such as alendronate, providing there are no contraindications. This can improve bone density and reduce the risk of further fractures.

Contraindications to calcium supplements include

·  Hypercalcaemia

·  Hypercalciuria.

Contraindications to bisphosphonates include

·  Abnormalities of the oesophagus - such as an oesophageal stricture

·  Renal impairment - in patients who take etidronate

·  Pregnancy

·  Breast feeding.

Diazepam – for muscle spasm. Max for one week. Be aware of addiction

Schober's test assesses lumbar flexion of the spine. To perform the test you should:

·  Put your finger at the level where the posterior iliac spine meets the vertebral column

o  This is usually about the level of the L5 vertebra

·  Using a measuring tape mark 5 cm below this level and 10 cm above this level

·  Ask the patient to slowly bend forward and try to touch their toes

·  The distance between the two marks should increase by 5 cm

o  Lumbar flexion is reduced if the increase in distance is less than 5 cm and this indicates a positive test

Clinical tip

A thorough examination can sometimes reveal important findings and often is very reassuring for the patient.

For References, please look up the learning module on BMJ learning