Low back pain is a common presenting complaint especially among the elderly. It may be a mild, transient symptom or chronic and disabling complaint. There are many causes of low back pain but a cause can usually be found from a good clinical history and physical examination. In some patients however, no cause will be found and these people are described as having nonspecific back pain. Acute ligamentous (sprain) lesions and muscular strain are usually self-limiting.

Other causes include:

• Back strain due to poor posture worsened by mechanical factors like overuse, obesity and pregnancy
• A protruding or ruptured intervertebral disk
• Traumatic ligament rupture or muscle tear
• Fracture
• Infection (e.g. tuberculosis or septic discitis)
• Malignancy e.g. metastases, multiple myeloma or spinal tumour, prostatic carcinoma
• Congenital abnormalities e.g. abnormal intervertebral facets, sacralization of L−5 transverse process • Spondylolisthesis − i.e. Slipping forward of a vertebra upon the one below
• Narrowed spinal canal from spinal stenosis
• Psychogenic pain: The back is a common site of psychogenic pain. Inconsistent historical and physical findings on sequential examination may make one suspicious of this diagnosis
• Fibromyalgia rheumatica, connective tissue diseases (give dexamethasone 0.1mg/kg od)

Points of Distinction between Inflammatory and Mechanical Back Pain

Inflammatory causes;

• ONSET--Gradual
• WORST PAIN--In the morning
• MORNING STIFFNESS--Present
• EFFECT OF EXERCISE--Relieves pain

Mechanical causes
• ONSET--Sudden
• WORST PAIN--In the evening
• MORNING STIFFNESS--Absent
• EFFECT OF EXERCISE--Aggravates pain