Module 6 - Musculoskeletal 1

• Back pain is pain or discomfort experienced in the back, ranging from mild to debilitating
• In 2002, 16% of people reported back pain, making it the third leading cause of total disease burden in 2023
• Back pain can be accompanied by pain in one or both legs

Spinal Causes of Back Pain

• Lumbar muscular sprain/strain
• Herniated nucleus pulposus (intervertebral disc)
• Spinal stenosis/osteoarthritis
• Lumbar spine fracture
• Degenerative disc disease
• Facet joint arthropathy
• Spondylosis/spondylolisthesis
• Infection: Discitis, osteomyelitis, epidural abscess
• Congenital disease: Severe kyphosis, severe scoliosis, transitional vertebrae
• Malignancy: Multiple myeloma, metastases, lymphoma, leukaemia, vertebral/spinal cord/retroperitoneal tumours
• Cauda equina syndrome
• Epidural haematoma
• Scheuermann disease (osteochondrosis)
• Inflammatory arthritis (often HLA-B27 associated): Ankylosing spondylitis, psoriatic spondylitis

Non-Spinal Causes of Back Pain

• Abdominal aortic aneurysm
• Pneumonia
• Connective tissue disease
• Shingles
• Pelvic inflammatory disease
• Prostatitis
• Endometriosis
• Gastrointestinal involvement: Pancreatitis, cholecystitis, peptic ulcer disease
• Renal involvement: Renal colic, pyelonephritis, perinephric abscess
• Inflammatory bowel disease (cause of inflammatory arthritis)
• Psoas abscess
• Sickle cell disease/crisis
• Sacroiliac/pelvic pain
• Infective endocarditis

Cauda Equina Syndrome

• Cauda equina syndrome (CES) is a rare condition involving dysfunction of multiple sacral and lumbar nerve roots in the lumbar vertebral canal, leading to potential permanent disability, including bowel, bladder, and sexual dysfunction
• Key signs and symptoms include:
  • 'Saddle anaesthesia': Reduced or loss of perianal sensation
  • Anal sphincter disturbance: Faecal incontinence, constipation, reduced or loss of anal tone
  • Urinary symptoms: Reduced urinary sensation, loss of desire to void, poor stream. Can progress to urinary retention or overflow incontinence.
• CES can present in three classic patterns:
  • Acutely with back pain as the first symptom of lumbar disc herniation
  • Chronic back pain with slow neurological progression to numbness and urinary symptoms
  • The end-point of a long history of chronic back pain with or without sciatica
• Causes of CES:
  • Large central lumbar disc herniation (L4/5 and L5/S1)
  • Spinal injury with fractures or subluxation
  • Spinal neoplasms (primary or metastatic)
  • Infective abscess or spinal osteomyelitis
  • Iatrogenic causes (spinal anaesthesia, epidural haematoma post-operatively, spinal manipulation)

Assessment of Back Pain

• Red flags indicating potentially serious underlying conditions:
  • History of cancer
  • Unexplained weight loss
  • Severe pain when supine and/or at night
  • Age over 50 years
  • History of significant trauma
  • Intravenous drug abuse
  • Recent bacterial infection or fever
  • Immune suppression (HIV, transplant, corticosteroids)
  • Saddle anaesthesia
  • Bladder dysfunction (urinary retention or incontinence)
  • Bowel dysfunction (faecal incontinence)
  • Neurological deficit in either or both lower limbs (especially if progressive)
  • Persistent symptoms for >4 weeks (recurrent presentations, worsening pain)
  • Pregnancy
  • Representation
• Key components of history taking:
  • Precipitating factors
  • Pain assessment
  • Neurological assessment
  • Systems review
  • Psychosocial history
• Yellow flag criteria, indicating psychosocial factors that may contribute to chronic pain:
  • Belief that pain and activity are harmful
  • Sickness behaviours
  • Low or negative moods, mental illness
  • Treatment that does not fit with best practice
  • Problems with compensation system
  • Previous history of back pain with time off work
  • Problems at work, poor job satisfaction
  • Overprotective family or lack of social support

Back Pain in Paramedicine

• Assessment and Management:
  • Structured history taking to rule out red/yellow flags, precipitating and exacerbating factors, medical history
  • Physical examination:
    • Functional capacity (range of movement, mobility, overall ability)
    • Observation of site to identify musculoskeletal injury or trauma
  • Patient education: Importance of mobilisation, use of heat/cold packs for muscle relaxation, analgesia
    • Heat is preferred as it relaxes the muscle and promotes blood flow
  • Pharmacological intervention starting with simple analgesics (paracetamol, ibuprofen), progressing to oral opioids (panadeine forte, oxycodone, tramadol)
  • Referral to GP, physiotherapist, or chiropractor if needed
  • Transport if flags or risk factors cannot be mitigated, patient has uncontrollable pain, inability to be independent (ADL)

Classifications of Acute Low Back Pain

• Non-specific acute low back pain (90-95% of cases):
  • Lumbar musculoskeletal origin (diagnosis of exclusion)
• Radicular syndrome (5-10% of cases):
  • Radicular pain, radiculopathy
• Serious pathology (rare):
  • These conditions need immediate action

Diagnosing Serious pathology

Spinal Fracture

• More common in patients:

  • 50 years, especially males > 65 years and females > 75 years

  • A referral for X-ray or CT scan should be considered
• Midline tenderness in a patient with a history of significant trauma
• History of osteoporosis
• History of cancer
• Sporting activity involving spinal extension, rotation or both (Pars interarticularis stress fracture)
• Prolonged systemic corticosteroid use
• Significant trauma

Axial spondyloarthritis (0.1 – 1.4%)

• Chronic low back pain (> 12 weeks) with onset before aged 45 years and one or more of the following:
• Laboratory tests, e.g. CRP, HLA-B27
• Referral for consideration of MRI to assess for sacroiliitis
• Inflammatory back pain with at least four of: insidious onset, onset aged ≤ 40 years, improvement with activity, no improvement with rest, pain at night (with improvement when getting up)
• Peripheral manifestations, e.g. arthritis, enthesitis, dactylitis
• Extra-articular manifestations, e.g. psoriasis, inflammatory bowel disease, uveitis
• Family history of spondylarthritis
• Response to NSAIDs

Spinal malignancy (0.2%)

• Personal history of malignancy
• Laboratory tests, e.g. FBC, CRP and PSA if male
• Imaging – MRI is often preferred because plain X-rays are not as specific or sensitive for detecting spinal malignancy
• Age > 50 years
• Unexplained weight loss
• Pain not relieved by rest
• Strong clinical suspicion

Cauda equina syndrome (0.04%)

• Bilateral leg symptoms, including bilateral lumbar radicular pain, lower limb weakness, sensory changes or progressive neurological deficits Cauda equina syndrome is an emergency, refer immediately for acute orthopaedic or neurosurgical assessment
• Urinary dysfunction, including impaired bladder or urethral sensation, hesitancy, urgency or poor stream
• Altered perineal sensation (subjective or objective) and reduced anal tone on per rectum examination

Spinal infection (0.01%)

• Fever (> 37.8°C), night sweats or chills Laboratory tests, e.g. FBC, CRP or ESR**), and imaging – MRI preferred
• Pain at rest or at night
• Immunosuppression
• Diabetes
• Alcohol use disorder Intravenous drug use
• Recent injury, dental or spinal procedure

Aneurysm, e.g. abdominal aortic aneurysm (1 – 2%)

• Palpable abdominal pulsatile mass
• Laboratory tests, e.g. FBC, renal function, lipids, HbA1c, to assess cardiovascular risk
• Referral for ultrasound. Urgent vascular surgery assessment if pulsatile mass is tender or patient with known AAA has new onset pain
• High cardiovascular disease risk
• Anticoagulant use
• Absence of musculoskeletal signs

Signs and Symptoms of Pain

Radiculopathy

• Occurs due to neural compression
• Objective loss of sensory or motor function (due to conduction block in axons of a spinal nerve or its roots)
• Numbness or paraesthesia in dermatomal distribution
• Weakness or loss of function (L1 – S1), e.g. footdrop
• Reduced leg reflexes (knee jerk for L3 – 4, medial hamstring for L5, ankle jerk for S1)
• May or may not be associated with radicular pain

Radicular pain

• Occurs due to nociceptive discharge of a nerve root or dorsal root ganglion typically in the presence of inflammation, with pain being felt in the peripherally innervated structures of the affected nerve
• Leg pain greater than back pain (and not temporally linked to back pain)
• Unilateral leg pain radiating caudally in a narrow band in a quasi-dermatomal distribution, with possible skip regions
• Sharp, lancinating, deep as well as superficial pain Leg pain exacerbated by coughing, sneezing or straining
• Positive crossed or straight leg raise test or positive slump test (L4, L5, S1, S2)
• Positive femoral stretch test (L2, L3, L4)
• Occasionally there are symptoms and signs of radiculopathy

Somatic referred pain

• Occurs due to nociceptive fibre convergence from the lower back onto second order neurons in the dorsal horn that also receive input from the lower limb
• Dull, deep ache, like an expanding pressure
• Referred pain concurrent with back pain, i.e. if the back pain resolves, or flares, then so does the referred pain
• Pain can be referred as far down as the foot when severe with possible skip regions
• Pain initially felt widely with difficult to perceive boundaries; pain remains in one location once established
• Absence of neurological symptoms or signs
• Can co-exist with radicular pain

Yellow Flags:

• These are psychosocial factors that may contribute to chronic pain

Behavioural

• Fear-avoidance behaviours, e.g. avoiding movement or activity for fear of making the pain worse, fearful of their prognosis
• Inactivity or sedentary lifestyle with a preference for extended rest
• High consumption of alcohol or other harmful substances
• Smoking
• Obesity
• Feeling worthless, lack of self-esteem
• Depression, anxiety or specific health anxiety, e.g. fear of procedures or needles
• Fear or distress, often with hypervigilance
• History of back pain Lack of coping strategies and resilience
• Tendency to catastrophise

Beliefs and attitudes

• Belief that pain and activity is harmful
• Expecting pain with movement
• Misinterpretation of significance of symptoms and magnification of symptoms
• Belief that pain must be absent before returning to work and normal daily activities
• Unrealistic treatment expectations or belief that pain is uncontrollable
• Passive attitude towards rehabilitation
• Poor motivation and adherence to treatment regimens
• Previous negative healthcare experience
• Excessive focus on their disability

Social

• Social withdrawal or reduced interest in socialising
• Lack of social support
• Over-protective or conversely, non-supportive partner or family
• Relationship stress
• Low income or compensation issues
• Low level of health literacy
• Low socioeconomic status
• Cultural factors

Work

• Physically demanding job
• Unsupportive work environment
• Poor job satisfaction
• Work-related stress
• Unsociable hours, e.g. shift work
• Poor work history