Family doctor

Overview:

• Back injuries are very common
• Most acute back injuries resolve rapidly
• It is best to remain active and at work if possible
• A few serious problems can occasionally result from back injuries

What causes back injuries?

Usually the cause will be a single event, where the tissues at some vulnerable spot in the back are stretched beyond their usual tolerance for stress.

The back is a very complex structure, with a delicate spinal cord encased within angled bones at the rear of a column of bones arranged like building blocks. Between these blocks are discs, which have a tough outer casing and a jelly-like centre.

In certain types of back injury, the casing of the disc can split and allow the centre contents to squeeze out. This is referred to as a "slipped disc".

If the disc presses on an adjacent nerve root, it can cause pain along the distribution of that nerve root, down the leg. This type of leg pain is called sciatica.

Other structures that can cause pain when injured include small joints at the rear of the spinal cord. These are called facet joints (between the vertebrae). In some athletes, e.g. fast bowlers in cricket, pain may arise from a stress injury to the bone.

Pain may also arise from irritated muscles which then go into spasm.

Other causes of back ache are much rarer and include infiltration of the bones of the spine with tumour deposits from spread of a cancer elsewhere in the body.

The exact identification of which structure is causing the pain is often difficult, and is not necessary in most cases.

What symptoms occur?

• Back pain, generally at the level of the structure that is injured
• Leg pain down the back of the leg if a nerve root is being irritated or pinched
• Muscle weakness, if persistent squeezing of a nerve root occurs
• Pins and needles in a particular part of the leg or foot if persistent squeezing of a nerve root exists
• Rarely, disturbance of bowel or bladder function (e.g. inability to pass urine) may occur. This is serious and requires urgent evaluation in hospital

What treatment is recommended?

Firstly, it is important to see your doctor for a medical evaluation. Your doctor is aware of the serious symptoms that require urgent referral to a specialist (see below).

If these are not present, the following advice is recommended:

1. Avoid activities that provoke pain, at least in the first few days after injury. Bed rest is rarely needed, but if so, it should be limited to 2 days or less. Longer periods of bed rest can impair recovery.

2. If back or leg pain is significant, regular doses of analgesics (pain killers) are advisable in the first week or two. Paracetamol is purely a pain reliever, whilst aspirin and other anti-inflammatory drugs also relieve inflammation. If you have a pervious history of peptic ulcer, your doctor may recommend newer cox-2 anti-inflammatory drugs (e.g. celebrex) that do not upset the stomach.

3. Gradually increase physical activity over the first week or two as symptoms subside. In most cases, it is advisable to remain at work performing modified duties. Particular activities that may have contributed to the injury (e.g. heavy lifting, bending or twisting) should be reviewed and modified if possible.

4. Manual therapy can be very helpful in the first few weeks after a back injury. Physiotherapists, osteopaths, chiropractors and some doctors are trained to provide this treatment. The most important aspect is to find a person with hands-on therapy skills who has a good record of success. Avoid people who spend most of their time hooking you up to a machine while they treat someone else.

5. If you have persistent sciatica which has not responded to manual therapy after 2-3 weeks, you may be referred for an epidural steroid injection. This is an injection of cortisone via a very fine needle designed to shrink down the swelling around a disc which is pressing on a nerve root. It can be dramatically effective, but is only worth considering if sciatica is present.

What about x-rays and scans?

In most back injuries, x-rays and scans are not necessary. If there has been enough force to cause a fracture (e.g. fall from a significant height, high speed motor vehicle accident) then x-rays are worthwhile.

In older people with back injuries, x-rays may reveal disc space narrowing. However, these findings need to be interpreted cautiously, as there may not be much correlation between the person's condition and the appearance of their x-ray. We treat people, not their x-rays.

Other investigations (e.g. CT scans and MRI scans) are much more detailed and much more expensive. Their major role is when surgery is being considered.

What are the serious symptoms?

The following symptoms are considered "red flags". That is, they may be a pointer to an underlying serious problem such as rheumatic disease or an associated fracture. Your doctor is the person who is best placed to evaluate those symptoms in your particular case.

• Disturbance of bowel or bladder function
• Bilateral sciatica - pain down both legs
• Significant trauma
• Weight loss
• History of cancer
• Fever
• Intravenous drug use
• Steroid use (e.g. prednisone tablets for asthma or arthritis)
• Patient aged over 50 years
• Severe, unremitting night pain
• Pain worse on lying down

What about surgery?

Surgery is not magic. It has a small but definite place in the treatment of some back problems. The most common indication for surgery in back disorders would be for a disc pressing on a nerve causing severe persistent leg pain, that is no better after an epidural steroid injection. Another less common indication would be for limiting slippage of one part of the spine on another part.

In summary:

Most back problems resolve rapidly - within days to weeks. Pain relief and manual therapy can speed progress in the early stages. Leg pain (sciatica) may require an epidural steroid injection. There is a small role for surgery.