Polio

Orthopaedic Infections

Poliomyelitis

Western Health Orthopaedic Registrar presenation – Poliomyelitis by Dr Todd Mason

Definition

  • Viral infection of the anterior horn cells of the spinal cord & brainstem (lower motor neuron cell bodies)

Incidence

  • Can affect any age
  • Probably > 10 million with residual deformities
  • Seen far less since the introduction of vaccination

Pathology

  • Virus gains entry to the body via the gut
  • Usually flu-like illness
  • If it attacks the anterior horn cells it causes varying° of paralysis
    • in isolated muscles or in muscle groups
  • Some of the neurons survive & the muscle regains power
  • after 6 months there will be no further return of power

Clinical

  • Following a trivial illness (diarrhoea or a sore throat) a small proportion develop meningitis
  • Muscle aches & tenderness are seen, passive stretching is painful
  • Paralysis follows within 2-3 days
  • muscles with short column of anterior horn cells more affected (eg tib ant)
  • hamstrings less affected because long column of horn cells at multiple levels
  • Can die from respiratory involvement
  • Starts to resolve after 7-10 days
  • Infective for 4 weeks from the onset of symptoms

Treatment

Acute

  • Symptomatic
  • Isolation
  • Respiratory support
  • Pain relief
  • Gentle passive physiotherapy

Recovery

  • Aggressive physiotherapy
  • Splinting
  • Muscle charting

Residual

  • 5 problems that require treatment
    1. Isolated muscle weakness (quadriceps)
    2. Deformity (due to unbalanced paralysis – may be correctable or fixed)
    3. Flail Joint (due to balanced paralysis)
    4. Shortening (due to lack of muscle activity ± contractures)
    5. Vascular dysfunction (cold, blue limbs)(? sympathectomy)

By Region

Upper Limb

  • Shoulder
    • Arthrodesis at 50 o abduction & 25 o flexion
    • will restore good function provided scapulothoracic muscles are OK
    • Contracted adductors will need division
  • Elbow
    • To restore flexion pect. major transfer to biceps tendon
  • Wrist
    • Arthrodesis will resolve instability & weakness problems & active muscles can be used for finger movement
  • Thumb
    • Weakness of opposition can be improve by transfer of FDS(to the ring finger) after winding it around FCU which acts as a pulley

Spine

  • Scoliosis
    • Long thoracolumbar curve is common + may extend to involve pelvis
    • Surgical correction may be indicated

Lower Limb

  • Hip
    • Balanced paralysis causes instability
    • Unbalanced paralysis often leads to flexion deformity that can be treated with flexor muscle slide or psoas transfer (as for SB)
    • Occasionally there will be fixed abduction secondary to pelvic obliquity & this can be treated with ITB & FL division
  • Knee
    • Weakness leads to instabilty, often requiring a caliper to keep the knee in extension for walking
    • Fixed flexion is common & the options are:
      • Hamstrings division
      • Hamstrings to Quads transfer
      • Supracondylar femoral extension osteotomy
  • Foot
    • Multiple deformities can occur & bony & soft-tissue procedures are often combined to restore shape & achieve muscle balance for varus or valgus deformity
      • Grice inlay fusion
        • Slot bone graft into vertical grooves on each side of the sinus tarsi, resulting in subtalar fusion
      • Triple Arthrodesis
      • Lambrinudi’s operation (for varus or valgus + foot drop)
        • Triple arthrodesis but the fully plantarflexed talus is slotted into the navicular with the forefoot in only slight plantaris (this corrects the footdrop as the talus can no longer plantarflex, whilst the slight equinus helps to stabilise the knee in extension in the stance phase of walking) for calcaneocavus deformity
      • Elmslie’s operation
        • 2 stages
          • triple arthrodesis with the foot in calcaneus, then corrected later by a posterior wedge excision & tenodesis using half of the tendo achilles for claw toes
      • flexor to extensor transfers if correctable
      • IPJ arthrodesis & transfer of extensors to the proximal phalanx if it is fixed