ANKLE FRACTURES

ANKLE FRACTURES - Heather C. Killie, MD
BASICS
DESCRIPTION
• Fractures involving the distal fibula (lateral malleolus) and/or distal tibia (medial malleolus and plafond)
• Includes a range of injuries to bones and ligaments of the ankle
GENERAL PREVENTION
• Proper shoe wear (i.e., flat, supportive shoes)
• Avoid running or walking on uneven or slick surfaces.
EPIDEMIOLOGY
• One of the most common fractures requiring orthopedic care
• Lateral malleolus more commonly involved (account for 2/3 of all ankle fractures)
Incidence
• Age-specific incidence increases in men >60 and women >50 years of age
• Highest incidence in elderly women (1)[B]
ALERT
Pediatric Considerations
• Pediatric will present with fractures involving the growth plates
• Most commonly a Salter-Harris I fracture of the distal fibula
RISK FACTORS
• Increased body mass index
• History of smoking
• No association between general health and risk for ankle fracture
PATHOPHYSIOLOGY
The location and pattern of injury depend on foot position and the direction of force applied. Most commonly the foot is plantarflexed and inverted, and the force is external rotation.
Axial load can cause a tibial plafond (a.k.a. pilon) fracture, which is an intra-articular fracture of the distal tibia where it articulates with the talus.
ETIOLOGY
Fall or twisting injury to the ankle
ASSOCIATED CONDITIONS
• Ankle sprains
• Syndesmosis injury
• Ankle or subtalar dislocation
• Fracture of the metatarsals, talus, calcaneus
• Osteochondral fracture (subchondral fracture of the distal tibia or talus)
• Neurovascular injury (very rare)


DIAGNOSIS
PRE HOSPITAL
• If ankle is obviously deformed, it should be reduced and provisionally splinted after adequate pain control is achieved.
• Place ice on ankle and elevate extremity
SIGNS AND SYMPTOMS
• Pain, swelling, and ecchymosis
• Pain or inability to bear weight
• Possible deformity
History
• Mechanism of injury
- Fall or twisting injury
• Timing of injury
• Past history of ankle injuries
• Any other injuries sustained
Physical Exam
• Inspect the ankle and foot for swelling and ecchymosis.
• Inspect the skin for tenting or lacerations.
• Palpate dorsalis pedis and posterior tibial pulses
• Palpate medial and lateral malleoli, proximal leg, and foot
• Sensory and motor exam of ankle and foot
• Rule out compartment syndrome (very rare), especially of the deep posterior compartment of the leg.
TESTS
Lab
Routine lab studies are not needed unless the fracture is operative.
Imaging
• Ottawa Ankle Rules help the clinician determine when to get x-rays. (2)[A]
• X-rays when patient has pain at either malleoli and 1 or more of following:
- Age >55
- Inability to bear weight
- Bony tenderness at posterior edge or tip of either malleoli
• 3 standard views: AP, Lateral, Mortise (15 internal rotation view)
• When foot pain present, get 3 views of foot
Diagnostic Procedures/Surgery
• Arthroscopy is an option in cases of persistent pain or suspicion of an OCD lesion.
• Open reduction, internal fixation in cases of instability (See "Treatment" section)
DIFFERENTIAL DIAGNOSIS
• Stress fracture
• Ankle sprain
• Osteochondral fracture
• Talus fracture
• 5th Metatarsal fracture
• Calcaneus fracture
TREATMENT
PRE-HOSPITAL
• If ankle is obviously deformed, it should be reduced with adequate pain control and provisionally splinted per first-aid protocol.
• Ice and elevate the extremity.
STABILIZATION
• As above if obvious deformity
• Place leg in a padded posterior splint to include toes to just below knee.
• If the fracture is open, remove any debris from the wound, place a moist dressing over the wound, and immediately contact an orthopedic surgeon.
• Obtain x-rays.
GENERAL MEASURES
Activity
• Non-weight bearing in all fractures
• EXCEPTION
- Isolated avulsion fractures of the tip of the lateral malleolus may be weight bearing as tolerated.
Nursing
• Apply ice.
• Instruct patient to keep leg elevated
• Control pain.
SPECIAL THERAPY
Physical Therapy
Early range of motion is key to prevent stiffness.
• Encourage toe and knee motion as soon as possible.
• Start ankle ROM as soon as there is evidence of fracture healing (usually 6 weeks).
MEDICATION (DRUGS)
• In general, ankle fractures are painful, particularly in the 1st 5-7 days following an injury. As the swelling decreases, so does the pain.
First Line
• Acetaminophen
• Opiod analgesics (i.e., hydrocodone)
• Avoid NSAIDs acutely (may delay healing of fractures)
Second Line
Non-opiod analgesics (i.e., tramadol)
SURGERY
• Absolute surgical indications
- Open fractures (fix within 6-8 hours)
• Relative surgical indications
- Gross instability (i.e., dislocation on presentation, bi- or tri-malleolar ankle fractures)
- Displacement after closed reduction attempt
- Displaced, comminuted distal tibia fractures
• Surgical options
- Open reduction internal fixation with plates and screws (most commonly)
- External fixation for comminuted distal tibia fractures
• Timing of surgery
- Within 6-8 hours if skin open
- After swelling decreased in all other cases (preferably not >1 week)
• Length of recovery
- In general, 6-8 weeks for healing
- 6-8 weeks in a cast or splint (longer if fracture involves both medial and lateral malleoli)
- 2-4 months for syndesmotic injury
- Orthopedist may allow range of motion after 4 weeks and place in removable cast boot (fracture pattern and surgeon dependent)
FOLLOW-UP
Most ankle fractures require close follow-up by an orthopedic surgeon (see "Referral" section)
DISPOSITION
• Patient should be transferred to the emergency department if
- Open fractures
- Dislocated ankle
- Neurovascular injury
- Possible compartment syndrome
• Otherwise, patient should be referred to an orthopedic surgeon
Admission Criteria
Admit to the hospital if
Open fracture
Neurovascular injury
Cannot maintain non-weight bearing status and requires physical therapy consultation
Concern of skin compromise
Concern of mechanism of injury (i.e., syncope, MI, head injury)
Discharge Criteria
When patient has completed the following
Able to ambulate with walker/crutches
Medical work-up (if needed) is completed
Appropriate orthopedic follow-up is arranged
Elderly patients may require a short stay in a rehabilitation facility.
Issues for Referral
• Most ankle fractures should be seen by an orthopedic surgeon within 5-7 days, earlier if a reduction is needed.
• Open fractures should be seen by an orthopedic surgeon immediately.
PROGNOSIS
• Good results can be achieved in most ankle fractures without surgery, provided the ankle mortise is maintained. (3)[B]
• Long term, some patients may develop ankle arthritis; timing is unpredictable.
• Effusion or pain can persist for up to 1 year.
COMPLICATIONS
• Non-operative
- Displacement of the fracture
- Malunion
- Skin breakdown
- DVT (rarely pulmonary embolism)
• Operative
- Infection
- Loss of fixation
- Nonunion or malunion
- Skin breakdown
- DVT (rarely pulmonary embolism)
PATIENT MONITORING
• Serial x-rays should be performed weekly for 4 weeks if there is any question about stability.
• Otherwise, x-rays should be performed at 2 weeks, 4 weeks, and 8 weeks or until the fracture is healed.
REFERENCES
1. Court-Brown CM, McBirnie J, Wilson G. Adult ankle fracturesan increasing problem? Acta Orthop Scand. 1998;69(1):43-47.
2. Stiell IG, Greenberg GH, McKnight RD, et, al. Decision rules for the use of radiography in acute ankle injuries: Refinement and prospective validation. JAMA. Mar 1993;269:1127-1132.
3. Michelson JD. Ankle fractures resulting from rotational injuries. J Am Acad Orthop Surg. 2003;11:403-412.