Chapter 42- ankle injuries Flashcards
What are the three components making up the lateral ligament complex of the ankle?
- Anterior talo-fibular
- Calcaneo-fibular
- Posterior talo-fibular
Describe a Weber A fracture
- Inversion adduction
- Medial malleolus has an oblique fracture line
- lateral malleolus may be fractured below the syndesmosis or the lateral ligament is injured
- Syndesmosis is intact
- Talus displaces medially
Describe a Weber B fracture
- Eversion; abduction; external rotation
- Fracture at the level of the syndesmosis which may be partially ruptured
- talus dispalces laterally
Describe a Weber C fracture
- Abduction, external rotation
- The fibular fracture is anywhere above the syndesmosis which is torn
- Talus displaces laterally
- Medial (deltoid) ligament) is only injured in combination with a push-off fracture of the lateral side of the ankle (Weber B or C)
Describe a plafond fracture
- Vertical compression causes fracture of the distal tibia extending into the ankle joint
- Usually due to a fall from a height, forcing the talus upwards into the tibia
- It is an intra-articular fracture
Recurrent episodes of instability of the ankle joint are common following which injury?
Lateral ligament injury
Findings on examination of an ankle injury
- Swelling
- Bruising
- Deformity if displacement or dislocation present
- Tender ++
- ?Crepitus if fracture present
- Feel whole length of fibula for tenderness or crepitus
What should the position of the foot be in an AP X-ray of the foot
Foot should be 15 degrees internally rotated
In children- ligament injury is rare, therefore, what diagnosis is more likely for an unstable joint?
-Epiphyseal injury
What ‘masqueraders’ should be excluded in suspected ankle injury
Ruptured Achilles or posterior tibial tendon and fractures of the hindfoot bones
Treatment of an acute mild/moderate tear of ankle ligaments
- Eversion strapping or lateral stabilizing ankle brace for 3/52- use extension plaster only for the longitudinal part of eversion strapping
- Active ankle exercises
Treatment of an acute severe tear of ankle ligaments
- Below knee POP with ankle at right ankles and walking heel for 4/52 then
- Eversion strapping or ankle brace (air cast) 4/52
- Muscle strenghtening and physiotherapy
- Operative repair followed by POP for 6/52 may be done (rarely indicated)
Treatment of chronic injury to the ligaments of the ankle
- Physiotherapy ++
- Brace
- Refer to specialist
What are the criteria for an acceptable position of maleolar fractures
- Tibio-talar congruity: Displacement <2mm
- Lateral maleolus: No lateral or posterior shift although talar shift of <2mm may be tolerated by the ankle. Fibular length may be restored
- Syndesmosis diastases: <2mm
- Posterior maleolar fracture of <20 % of the articular surface can be ignored
- Medial mallelous: displacement is seldom important unless it reflects tibio-talar incongruity
Displacement beyond this–> reduction (closed or ORIF)
What cast is required in weber B and C to maintain reduction?
An above knee cast with 30 degrees knee flexion is needed to control rotation
If an ankle fracture has been reduced and POP applied what is the management at 6 weeks?
- POP off and Xray
- Initially undisplaced: Apply tubigrip , mobilize ankle
- Initially displaced: POP and walking heel or pad. Start partial weight bearing. Week 10-12, POP off. Tubigrip. Mobilize
Which ankle fracture needs surgery in preference to treating with cast immobilisation
Weber C
What is the treatment of plafond fractures
- Needs hospitalization for traction or surgery
- If severely comminuted, calcaneal pin skeletal traction and early ankle motion, if no surgical expertise available
- external fixation: tibia to foot
- Open reduction and external fixation
Complications of ankle fractures
- Infection
- Post-traumatic arthritis
