Back Pain Flashcards
What is vertebral osteomyelitis?
Infection of the vertebrae
What is the aetiology of vertebral osteomyelitis?
- Mostly haematogenous, most commonly staph. aureus
- May be associated with abscess - epidural, psoas
- As the vertebral end plates weaken, vertebrae may collapse leading to kyphosis or vertebra plana (flat vertebra) and disc space may reduce
What are the risk factors of vertebral osteomyelitis?
- PWID
- Poorly controlled diabetes
- IV site infections
- GU infections
- SSTI
- Post operative
- Primary bacteraemia in the elderly
What is the presentation of vertebral osteomyelitis?
Patients present with insidious onset of back pain (most commonly lumbar) which is constant and unremitting
- Paraspinal muscle spasm
- Spinal tenderness
- May have fever and/or systemic upset
- Severe cases may have an associated neurological deficit
What are the investigations of vertebral osteomyelitis?
- Bloods - raised CRP
- MRI - extent of infection and any abscess formation, imaging psoas sign indicates spondylodiscitis
- Blood cultures may indicate the causative organism (usually Staph. aureus including MRSA but atypical infections can occur in the immunocompromised)
- Consider endocarditis - look for clubbing, splinter haemorrhages, murmur, consider ECHO
What is the management of vertebral osteomyelitis?
- High dose IV antibiotics after CT guided biopsy to obtain tissue culture
- Antibiotics may be required for several months and response is assessed clinically and by serial CRP
- Around half of all patients go on to spontaneous fusion and resolution
Surgery
- Indications for surgery include inability to obtain cultures by needle biopsy, no response to antibiotic therapy, progressive vertebral collapse and progressive neurological deficit
- Surgery involves debridement, stabilization and fusion of adjacent vertebrae
What is Pott disease?
vertebral body osteomyelitis and intervertebral discitis from tuberculosis (TB)
What is the aetiology of vertebral TB?
- 1/2 have skin and soft tissue infection
- Less than half have pulmonary TB
- Immunosuppression/HIV
What is the presentation of vertebral TB?
- Often no systemic symptoms
- Clinical presentation is characteristically slow and insidious
- Back pain
- Lower limb weakness/paraplegia
- Kyphotic deformity
What are the investigations of vertebral TB?
- Imaging - x-ray, MRI
- Check for immunosuppression/HIV
What is the management of vertebral TB?
- Imaging - x-ray, MRI
- Check for immunosuppression/HIV
What is mechanical back pain?
Recurrent relapsing and remitting back pain with no neurological symptoms
What is the aetiology of mechanical back pain?
- Presents 20-55
- Obesity
- Poor posture
- Poor lifting technique
- Lack of physical activity
- Depression
- Facet joint OA
- Degenerative disc prolapse
- Spondylosis - where the IV discs lose water content with age, resulting in less cushioning and increased pressure on the facet joint which can lead to secondary OA
What is the presentation of mechanical back pain?
- Pain in lumbosacral region, buttocks and thighs
- Leg pain will be referred in nature (dull, gnawing, ill-defined) and rarely below the knee
- Mechanical pain - varies with time and activity
- Patient well with no ‘red flag’ symptoms
- Patient tends to have had several previous ‘flare ups’
What is the management for mechanical back pain?
- Advice:
- Try walk 30 mins a day
- If not possible - comfortable period of time, repeated to try and build up to 30 mins
- Try to stay at work
- Restrict rather than avoid activity
- Weight control if overweight
- Try walk 30 mins a day
- Analgesia - NSAIDs first line, add weak opiates if needed
- Physiotherapy
- Prognosis good - 90% better in 6 weeks
- Spinal stabilization surgery is controversial
What is an acute disc tear?
An acute tear can occur in the outer fibrosis of an intervertebral disc which classically happens after lifting a heavy object (e.g. lawnmower)
What is the presentation of an acute disc tear?
Pain is characteristically worse on coughing - coughing increases disc pressure
What is the investigation for an acute disc tear?
MRI
What is the management of acute disc tear?
- Analgesia and physiotherapy
- Symptoms usually resolve but can take 2-3 months to settle
What is sciatica?
Characteristic pain felt in the lower back, buttocks and the posterior and lower leg that results from compression of any of the 5 nerve roots that contribute to the sciatic nerves
What is the aetiology of sciatica?
Compression of a nerve root, most commonly L5/S1
What is the pathophysiology of intervertebral disc prolapse in sciatica?
- Intervertebral discs consist of concentric collagenous fibres (the annulus fibrosus) surrounding a central nucleus (the nucleus fibrosus) of degenerated collagen
- Healthy discs contain a great deal of water
- As a result of aging the discs become dehydrated and weaken - more prone to prolapse
- Prolapse of a disc occurs when there is a defect in the annulus fibrosus that allows the nucleus to herniate out
- Herniation often occurs as the result of strenuous physical activity involving the lumbar spine
- The prolapsed disc material can press (impinge) on an exiting nerve root resulting in pain and altered sensation in a dermatomal distribution as well as reduced power in a myotomal distribution
- The commonest site for this to occur in the spine is the lower lumbar spine with the L4, L5 and S1 nerve roots contributing to the sciatic nerve and pain radiating to the part of the sensory distribution of the sciatic nerve