Non-specific back pain

Back pain is a common ED presentation. Usually, the non-specific pain is mild to moderate and is aggravated by movement and relieved with rest. There are no risk factors for a serious disease on the history and physical examination. 

Pain lasting >6 weeks is an indicator of more serious disease, since most episodes of nonspecific back pain (80% to 90%) resolve within 6 weeks. 

Red Flags

• Trauma (Fracture)
• Unexplained Weight Loss (Malignancy, Metastasis)
• Neurologic Symptoms (Coed COmpression)
• Age <18 years old and >50 years old (BOny abnormalities, Spinal Stenosis, AAA)
• Fever (Infection - Systemic, Osteomyelitis, Epidural Abscess)
• IVDU (Spinal Infection)
• Steroid Use, Immunocompromised (Infection)
• H/O Cancer (Metastasis)

Injection drug user + Back Pain = Spinal infection (Osteomyelitis, Epidural Abscess)

Elderly + Back Pain - Think Aortic Pathology

Bowel or bladder incontinence + Back Pain = Cauda equina syndrome

Back Pain - Critical documentation components

• Fever
• Localised warmth/tenderness
• Abdominal Masses
• Renal Angle Tenderness
• Sensory-Motor Exam (Perianal/Saddle Anesthesia)
• Reflexes
• Rectal Exam (Tone, Masses) - Must be performed in those with neurologic complaints or findings or other red flags for back pain
• SLRT (screening examination for a herniated disk) - With the patient lying supine, lift each leg separately to approximately 70 degrees in an attempt to produce radicular pain. A positive straight leg raise test causes a radicular pain radiating below the knee of the affected leg. This pain is worsened by ankle dorsiflexion and improved with ankle plantar flexion or decreasing leg elevation. 

Hip Flexion – L2 
Knee Extension – L3
Ankle Dorsiflexion – L4 
Great toe flexor – L5 

Ankle Plantarflexion – S1 

ED Management

• FBC, ESR/CRP, Urine Analysis, ALP, Ca (Only if clinically indicated)
• LS Spine X-Ray (with h/o trauma)
• For most patients, no testing is required
• MRI/CT Myelogram in suspected Epidural Abscess

Patients who resume their normal activities to the furthest extent tolerable recover more rapidly than those bed rest. Management options include:

• Analgesics (Paracetamol + NSAIDs with PPI cover if concerned about GI bleed). 
• Muscle relaxants (Diazepam, 5 to 10 milligrams) 
• Local application of heat 
• Manipulative therapy - Controversial treatment 
• Physical modalities (traction, diathermy, exercise, US treatment, TENS) - Questionable benefit

Take Home

• Watchful waiting (6-8 weeks) ensures appropriate utilisation of resorces and reduces unnecessary radiation exposure. 
• Set expectations and arrange follow up - Patient may expect some sort of imaging. Clarify this and let them know what symptoms concern you.

Further Reading

https://www.rcemlearning.co.uk/foamed/back-pain-advice-know-say/

https://www.rcemlearning.co.uk/references/lower-back-pain/

Posted by:

              

     Lakshay Chanana

     

     ST4 Trainee

     Royal Infirmary of Edinburgh

     Department of Emergency Medicine

     Edinburgh

     Scotland

     @EMDidactic