Back pain Flashcards
What are the red flags for sinister causes of back pain?
- Age 55
- Acute onset in elderly people
- Constant pain
- Pain at night
- Fever, night sweats, weight loss (suggests lymphoma or infective cause e.g. TB)
- History of malignancy
- Abdo mass
- Thoracic back pain (ank. spon)
- Morning stiffness
- Neurological disturbance
- Sphincter disturbance
- Immunosupression e.g. steroids/HIV
- Leg claudication or exercise related leg weakness (spinal stenosis)
What neurosurgical emergencies may present with back pain?
Acute cauda equina compression
Acute cord compression
What are the causes of acute cord/cauda equina compression?
Bony mets Karge disc protrusion Myeloma Cord or paraspinal tumor TB Abscess
Describe the stages of examination when a patient presents with back pain
- With the patient standing, assess the extent and smoothness of lumbar forward/lateral flexion and extension
- Clinical tests for sacroiliitis
- Neurological deficits
- Examine for nerve root pain
- Look for signs of generalised disease
What are the clinical tests for sacroiliitis?
- Direct pressure
- Lateral compression
- Sacroiliac stretch test: pain on adduction of the hip with the hip and knee flexed
How do you test for neurological deficits which might be the cause of back pain?
- Test lower limb sensation, power and deep tendon and plantar reflexes.
- Digital rectal examination for peri-anal tone and sensation (loss of anal tone on PR indicates cauda equina compression)
Where is pain felt if there is an L2 lesion? What movements are weakened? What reflexes are affected?
- Pain is felt across the upper thigh
- There is weakness of hip flexion and adduction
- No reflexes are affected
Where is pain felt if there is an L3 lesion? What movements are weakened? What reflexes are affected?
- Pain is felt across the lower thigh
- There is weakness of hip adduction and knee extension
- The knee jerk reflex is affected
Where is pain felt if there is an L4 lesion? What movements are weakened? What reflexes are affected?
- Pain is felt across the knee to the medial malleolus
- There is weakness of knee extension, foot inversion and dorsiflexion
- The knee jerk reflex is affected
Where is pain felt if there is an L5 lesion? What movements are weakened? What reflexes are affected?
- Pain is felt across the lateral shin to the dorsum of the foot and big toe
- There is weakness of hip extension and abduction, knee flexion, and foot and big toe dorsiflexion
- The big toe jerk reflex is affected
Where is pain felt if there is an S1 lesion? What movements are weakened? What reflexes are affected?
- Pain is felt across the posterior calf to lateral foot and little toe
- There is weakness of knee flexion, foot and toe plantar flexion and foot eversion
- The ankle jerk reflex is affected
What worsens pain felt due to an L2-S1 nerve root lesion?
Coughing or bending forward
What is a positive straight leg test?
The straight leg test is positive if raising the leg with the knee extended causes pain below the knee
What is Lasegue’s sign?
A positive straight leg test where dorsiflexion of the foot when the leg is raised increases pain experienced by the patient
What is suggested by a positive straight leg test?
Irritation to the sciatic nerve
What nerve roots are tested by the straight leg test?
L4, L5, S1
What is the most common cause of a positive straight leg test?
Lumbar disc prolapse
What is the femoral stretch test?
Pain in the front of the thigh on lifting the hip into extension with the patient lying face downwards and the knee flexed
What nerve roots are tested by the straight leg test?
L4 and above
What are the causes of back pain in 15-30 year olds?
Prolapsed disc Trauma Fractures Ankylosing spondylitis Spondylolisthesis Pregnancy
What is spondylolithesis?
A forward shift of one vertebra over another which is congenital or due to trauma
What are the causes of back pain in 30-50 year olds?
Degenerative spinal disease
Prolapsed disc
Malignancy (primary or secondary)
Which cancers metastasise to bone?
Thyroid Kidney Breast Prostate Lung
What are the causes of back pain in >50 year olds?
Degenerative Osteoporotic vertebral collapse Paget's Malignancy Myeloma Spinal stenosis
What are the causes of spinal infection?
Usually staphylococcal
Also: Proteus E. coli S. typhi TB
What are the symptoms of acute cauda equina compression?
Alternating or bilateral root pain in legs
Saddle anaesthesia (peri-anal)
Loss of anal tone on PR
Bladder +/- bowel incontinence
What are the symptoms of acute cord compression?
Bilateral pain
LMN signs at level of compression
UMN and sensory loss below compression
Sphincter disturbance
In what causes of back pain might ESR and CRP be raised?
Infection
Myeloma
Tumour
For what possible differential of back pain would you check ALP?
Paget’s
What imaging techniques are used if it is felt necessary to image the spine following episodes of back pain?
MRI is the imaging technique of choice. Can detect disc prolapse, cord compression, cancer, infection or inflammation e.g. sacroiliitis
(X-rays can exclude bony abnormalities but are generally not indicated)
How should non-specific back pain be managed?
Focus on education and self management
Advise patients to continue with normal activities and be active
Manage pain to allow this- regular paracetamol +/- NSAIDs +/- codeine
Consider low dose amitriptyline if these fail
Offer physiotherapy, acupuncture or an exercise program if not improving
Address psychological issues which may predispose to developing chronic pain and disability
