II. Pathophysiology

  1. Fifth Metatarsal has thinnest cortical thickness of any Metatarsal

III. Types: Based on landmarks along joint between 4th and 5th Metatarsals proximally

  1. Tuberosity Avulsion Fractures (Styloid Fractures, Pseudo-Jones Fracture, Zone 1)
    1. Proximal to the joint between 4th and 5th Metatarsals
    2. Mechanism: Lateral Ankle Sprain (inversion injury while foot plantar flexed)
    3. Typically heal without complications
  2. Metaphyseal-Diaphyseal Junction Fractures (Jones Fracture, Zone 2)
    1. Fracture line extends toward the joint between 4th and 5th Metatarsals
      1. Occurs 1.5 to 3 cm from the tip of the tip of the Metatarsal
    2. Mechanism: Sudden "cutting" motion side-to-side while the heel is off the ground
      1. Forceeful adduction to plantar flexed foot
    3. High risk area for non-healing Fractures
      1. Lies in the vascular watershed zone (at risk for poor healing, non-union)
  3. Diaphyseal Stress Fractures (Zone 3)
    1. Distal to the joint between 4th and 5th Metatarsals
    2. Mechanism: Recurrent Trauma such as jumping and pivoting in young athletes (Stress Fracture)
      1. Insidious pain onset with activity
    3. Highest risk area for non-healing Fractures

IV. Symptoms

  1. Distribution: Lateral Foot Pain
  2. Provocative: Walking
  3. Timing:
    1. Acute Fractures: Sudden onset
    2. Stress Fractures: Gradually progressive and increased with activity

V. Signs

  1. Localized swelling and Ecchymosis at the base of the fifth Metatarsal

VI. Imaging: XRay demonstrates Proximal Fifth Metatarsal Fracture

  1. See Proximal Fifth Metatarsal Fracture Grading Based on XRay
  2. See Types above for determining Fracture type
  3. Differential diagnosis on XRay of Proximal Fifth Metatarsal Fracture look-alikes
    1. Accessory bones (smooth, rounded densities surrounded by cortex)
    2. Styloid apophysis (children and teens)

VII. Management: Tuberosity Avulsion Fractures (Styloid Fractures)

  1. Indications for orthopedic referral
    1. Displaced tuberosity avulsion Fractures (>3 mm)
    2. Nonunion Fractures
    3. Cuboid-Metatarsal joint with >1-2 mm step-off
    4. Fracture fragment involves more than 60% of the Metatarsal-Cuboid joint surface
  2. Protocol for uncomplicated, non-displaced tuberosity avulsion Fractures
    1. Option 1
      1. Soft Bulky Dressing and weight bearing
    2. Option 2 (if pain despite Option 1)
      1. Hard soled shoe or cast boot and weight bearing (use for 5-6 weeks)
    3. Option 3 (if pain despite Option 2)
      1. Short leg walking boot or cast
  3. Protocol for minimally displaced tuberosity avulsion Fractures (<3 mm)
    1. Short leg walking boot or cast for 2 weeks
    2. Progressive ambulation and range of motion follow immobilization
    3. Reevaluation every 2 weeks and anticipate healing by 4-8 weeks
    4. Repeat XRay at 6-8 weeks to document healing (sooner if persistent pain on ambulation after 4 weeks)
  4. Course
    1. Anticipate asymptomatic by 3-6 weeks (pain may persist up to 8 weeks)
    2. Anticipate healed with union on XRay by 8 weeks

VIII. Management: Diaphyseal Fractures (Jones Fracture or Diaphyseal Stress Fractures)

  1. Indications for orthopedic referral
    1. See Fifth Metatarsal Fracture for absolute referral indications
    2. Consider Consultation in all patients given higher risk of non-union
    3. Athletes may also benefit from referral by decreasing duration of healing time
    4. Displacement >2mm
    5. Inadequate healing after immobilization for 12 weeks
    6. Non-union on xray
  2. Initial management
    1. Posterior splint
    2. Non-weight bearing
    3. Follow-up in 3-5 days
  3. Options: Non-displaced Jones Fracture (acute diaphyseal Fracture)
    1. Consider early surgical fixation in athletes
    2. Non-weight bearing short-leg cast or boot for 6-8 weeks
      1. Start weight bearing and PT if callus formation and no point tenderness at 6-8 weeks
      2. Continue non-weight bearing for additional 4 weeks and re-evaluate if inadequate healing
    3. Anticipate 6-10 weeks total of immobilization and up to 12 weeks for full healing
      1. Surgical repair may ultimately be needed in those managed with immobilization
  4. Options: Diaphyseal Stress Fracture Type I (early, See Torg Classification)
    1. Same management for Jones Fracture above
  5. Options: Diaphyseal Stress Fracture Type II (delayed, See Torg Classification)
    1. Early surgical fixation or
    2. Non-weight bearing cast for up to 20 weeks
  6. Options: Diaphyseal Stress Fracture Type III (nonunion, See Torg Classification)
    1. Surgical fixation or
    2. Non-weight bearing cast for up to 16 weeks and pulsed electromagnetic fields
      1. Holmes (1994) Foot Ankle Int 15: 552-6 [PubMed]
  7. References
    1. Dameron (1995) J Am Acad Orthop Surg 3:110-4 [PubMed]

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