Dr. Kevin Yip

Dr Kevin Yip
Orthopaedic Surgeon
MBBS(UK), FRCS(EDIN), FAM(SING), FHKCOS(ORTHO)

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Metatarsal Fracture

Basics
Description
  • Fractures of the forefoot:
  • Classification:
    • Metatarsal head, neck, or shaft fractures
    • Stress fractures most commonly involve the 2nd metatarsal and result from repetitive overuse.
    • 5th metatarsal fractures can be subdivided:
      • Avulsion fractures, which are proximal to the metaphysis (called pseudo-Jones fractures when the 5th metatarsal is involved)
      • Jones fractures are fractures of the 5th metatarsal at the metaphyseal-diaphyseal junction; they are notoriously unstable.
      • Diaphyseal stress fractures
      • Synonyms: Jones fracture; Pseudo-Jones fracture; Stress or marching fracture
General Prevention
  • Avoid foot trauma.
  • Modify training regimens to avoid overuse.
    • Gradually increase time and distance when starting or changing a running program.
    • Use new running shoes that are not overly worn.
Epidemiology
Occurs in both genders at all ages
 
Incidence
  • These injuries are common, especially 5th metatarsal fractures in athletes.
  • Fractures also are common in osteoporotic females.
Risk Factors
  • Stress fractures of the metatarsals occur with excessive training or repetitive stress in athletes or with a sudden increase in the level of exercise of any person.
  • Osteoporosis
Etiology
The injury usually is a result of a direct blow, inversion injury, or overuse.
 
Associated Conditions
  • Compartment syndrome (rarely)
  • Lisfranc dislocation
Diagnosis
Signs and Symptoms
  • Pain
  • Swelling
  • Deformity
  • Ecchymosis
  • Difficulty bearing weight
  • Tenderness over the affected metatarsals
History
Direct trauma, inversion injury to foot, or sudden increase in training regimen
 
Physical Exam
  • Physical examination usually reveals point tenderness over the involved metatarsal.
  • Severe swelling of the entire forefoot commonly occurs.
Tests
Imaging
  • Plain films usually are diagnostic.
    • AP, lateral, and oblique foot images are mandatory.
    • Alignment in the lateral film is the most important aspect in management of these injuries.
  • If plain radiographs are inconclusive, bone scanning or MRI may be helpful in detecting occult fractures.
Pathological Findings
Longstanding fractures may show signs of delayed union or nonunion.
 
Differential Diagnosis
  • Soft-tissue contusion
  • Sprain
  • Lisfranc dislocation
Treatment
General Measures
  • Isolated metatarsal neck or shaft fractures can be treated with a well-fitted below-the-knee cast or postoperative shoe and weightbearing as tolerated for 3-4 weeks, followed by a well-padded shoe.
    • Length of time in a cast should be limited to avoid complications.
  • If angulation is >10°, closed reduction with or without stabilization with percutaneous PINS may be required.
  • The most important alignment is the sagittal alignment (i.e., apex inferior) because malunion in this plane may cause metatarsalgia or pain on the dorsum of the foot.
    • Displacement in the transverse plane usually is well tolerated in the 2nd-4th metatarsals.
    • Angulation in this plane of the 1st or 5th metatarsal may cause difficulty with shoe wear and should be reduced.
  • Injuries with multiple metatarsal fractures often are unstable and require open reduction and internal fixation with small-fragment plates or Kirschner wires.
  • Metatarsal head fractures are rare and, if they are unstable after reduction, may require open reduction and internal fixation.
  • Closed treatment consists of 4-6 weeks in a below-the-knee walking cast.
  • Patients with Jones fractures that are treated closed should remain nonweightbearing for 8 weeks.
    • These fractures have a high rate of subsequent displacement and should be stabilized operatively if they are displaced >2 mm.
    • Some authors advocate operative stabilization in all active individuals, even for fractures with <2 mm displacement.
  • Avulsion fractures of the 5th metatarsal need only a postoperative (hard-soled) shoe.
  • Patients with stress fractures need activity modification for 3-4 weeks and protection in a cast or orthosis.
  • Metatarsal head fractures usually result from a direct blow to the foot.
    • Closed reduction usually is successful and stable.
    • If the fracture is unstable, percutaneous pinning with Kirschner wires may be used.
Pediatric Considerations
  • Growth plate injuries to the metatarsals are rare but may occur when the chondroepiphysis is avulsed, a fracture extends into the epiphysis, or the condylar surface of the secondary ossification center is avulsed.
  • These fractures can be treated in a below-the-knee walking cast for 3-4 weeks.
  • Overgrowth is more common than growth inhibition.
Special Therapy
Physical Therapy
  • No need for routine physical therapy
  • Once healed, patients usually have little difficulty in returning to activities of daily living.
Medication
Recommended medications are analgesics other than NSAIDs because the latter may inhibit bone healing.
 
Surgery
  • The goal is anatomic reduction to restore the weightbearing complex of the forefoot.
  • Indications:
    • 2-4 mm of shortening or elevation of the 2nd-4th metatarsals; less deformity is accepted in the 1st and 5th metatarsals.
    • Other surgical indications are delayed union or nonunion.
  • Metatarsal fractures:
    • Open reduction and internal fixation: Dorsal incision with 1/3 tubular plates and 3.5-mm cortical screws on the tension side
    • Intramedullary fixation with Kirschner wires extending out the distal tip of the toe
  • Jones fractures:
    • May be treated with open reduction and internal fixation with a long intramedullary malleolar screw because of the increased tendency to nonunion
    • Patients with Jones fractures treated by open reduction and internal fixation can be advanced gradually in weightbearing after 2 weeks.
  • Nonunions (usually apex plantar):
    • Should be treated by resection of the edges of the malunion, slight overcorrection of the angular deformity, and stabilization with percutaneous pinning.
    • Bone grafting also may be required.
Follow-up
Disposition
Patients generally benefit from walking aides, such as crutches, in the initial postinjury period.
 
Prognosis
The prognosis is good if no substantial sagittal displacement occurs at the time of healing.
 
Complications
  • Transfer metatarsalgia
  • Neuroma
  • Delayed union
  • Nonunion
  • Difficulty with shoe wear
Patient Monitoring
  • Follow-up radiographs should be obtained 1 week after reduction to ensure satisfactory alignment, and a 2nd set should be obtained 4-5 weeks after injury.
  • Follow-up radiographs should show callus and healing of the metatarsal fractures.
  • Clinically, the patient should no longer be tender over the healed fracture site.
Miscellaneous
Codes
ICD9-CM
825.25 Fracture of metatarsal bones
 
Patient Teaching
Patients should be warned about the risks of nonunion and possible metatarsalgia.
 
FAQ
Q: Should a cast be applied to all metatarsal fractures?
A: Most metatarsal fractures can be treated with a hard-soled shoe. Displaced fractures may be considered for surgery. Jones-type fractures should be treated with a cast or surgery.

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