Back Pain

Background 30 million adults in UK /yr experience back pain 1/3 experience pain> 12 months and 1/5 of above will be off work >3/12 Costs NHS £1.3 million/day Large scale all around cost- NHS approved campaign- BackCare Awareness Week October 2014

Red Flags  Focal neurological symptoms/signs- incl. Cauda Equina  Trauma  Thoracic region pain  Unintentional weight loss  Long term steroid use  Night sweats- symptoms of general malaise  History of Bone disease

Cauda Equina Syndrome(CES) Back pain ‘Saddle anaesthesia’- S3- S5 dermatome Bowel and bladder dysfunction Paraplegia Multiple causes Urgent MRI- low threshold if high clinical suspicion Tx- Urgent Decompression/Discecto my ‘Time is function’

Disc Prolapse Usually following minor-moderate injury More likely in young-middle aged Unlikely to be >70s due to loss of volume of nucleus pulposus Higher propensity- L4/L5 and L5/S1

Spinal Stenosis Cervical and Lumbar stenosis- common sites Central – usually Discomfort whilst standing-94% Symptoms related to level of stenosis Lumbar flexion helps

As a continuum… Minor/Moderate injury Acute onset pain Resolves with rest /analgesia Slight protrusion of nucleus pulposus Re-injury Further prolapse Neurological deficit either transient/established Re-injury Increased risk for CES Spinal stenosis Minor Injury

Other causes Leriche syndrome- buttock pain- aorto-iliac occlusive disease Part of disease process- Multiple Myeloma, Prostate Ca Potts’ abscess-extrapulmonary TB

Pain In >70% of patients presenting with back pain- Chronic LBP Usually spasmodic exacerbations on a background of constant pain Can usually treat the exacerbations, background pain- poorly controlled Area where subjective scoring of pain has significant variations with time

Case Scenario 38 yr old lady presented with lower back pain of 2/52 Minor back injury 2/52 Worsening pain over the previous 3-4/7 Recent weight gain Shooting pain down from back and front to left knee Numbness over left lateral thigh No associated bladder or bowel dysfunction noted

Examination findings In obvious discomfort No evidence of unilateral muscle wasting Some generalised discomfort over L3/L4 vertebrae but no pinpoint tenderness noted Flex hip to 110 degrees (L side), internal and external rotation preserved Lumbar flexion largely preserved SLR normal both sides, lasegue test negative Femoral stretch test equivocal on left side Reduced sensation over lateral aspect of left thigh Slightly diminished reflexes at left knee> R knee Power reduced to 4/5 LLL possibly due to pain

Lower limb dermatome

Lasegue’s test and SLR SLR- note angle at which pain is reproduced Lasegue test- dorsiflexion with SLR- reproducing pain Both indicative of L5/S1 primary nerve root involvement

Discussion of findings No evidence of spinal cord compression No evidence of cauda equina No evidence of hip involvement SLR and Lasegue's test being negative- rules out true sciatica True sciatica- burning pain radiating to heel and lasegue's test would be positive- compress L5/S1 disc space

Likely explanation Femoral nerve roots involvement- primarily L3/L4- possibly entrapment ? Disc prolapse Could be a component of meralgia paraesthetica Classical symptoms of burning pain and localised anaesthesia Lateral cutaneous femoral nerve involvement Usually related to diabetes, weight gain, tight clothing related

Management Simple analgesia Weak opioids Large role of anti-neuropathic type of medications- e.g. gabapentin, amitriptylline Large proportion of patients get symptomatic relief Small proportion develop longstanding pain The above management was instituted Explained if pain does not settle Will need imaging- MRI, EMG(not routinely)