5) Lateral Ankle (Inversion) Injury Flashcards
Lateral ankle (inversion) sprains incidence
- 40 % of all sports injuries (most common injury in all of sports)
- 25 % of all time lost in sports
- Lateral: 85 %
- Medial: 5 %
- Syndesmosis: 10 %
Sprain
- Stretching injury which may involve partial or complete tearing of the lateral ankle ligaments
Lateral ankle inversion injury anatomy
- Shape of the talar dome: Wide anterior and narrow posterior
- Results in decreased frontal plane stability of the ankle when plantarflexed
- Increased stability with ankle dorsiflexion
STJ and ankle joint biomechanics
- Subtalar joint: 2:1 inversion to eversion ratio
- “Ankle” inversion is generated at the subtalar joint
Biomechanics: contributing factors
- Ankle equinus
- Gastrocnemius / soleus weakness
- Forefoot / rearfoot deformity
- Transverse plane abnormality
Lateral ankle injury history
- Mechanism ?
- Could bear weight initially ?
- History of previous injury, treatment and outcome ?
- Audible “pop” ?
- Immediate treatment ?
- Inappropriate shoe gear
- Excessive cushioning; shoe or surface
- Irregular surface (ie some ones’ shoe !)
- Any contributory neurological history
Palpation on physical examination
- Lateral malleolus
- Anterior talo – fibular ligament (ATF)
- Calcaneofibular ligament
- Posterior talofibular ligament
- Anterior – inferior syndesmosis
- Medial malleolus
- Deltoid ligament
- Achilles tendon
- Fifth metatarsal base
- Calcaneal anterior process
Physical tests
- Squeeze test: anterior – inferior syndesmosis
Anterior drawer test (push – pull test; “dimple sign”) - Muscle testing (esp. peroneals and flexors)
- Dorsi / plantarflexion of the MTPJ: shepards fracture / flexor tendon injury
Lateral ankle sprain physical examination order
- Vitals
- Begin proximal
- Begin at least painful areas
Syndesmotic injury tests
- Squeeze test
- Tibio–talar shuck test
- External rotation test
Lateral ligaments palpation
- Anterior talo – fibular
- Calcaneofibular
- Posterior malleolus
Lateral ankle sprain grading
- Grade 1: Partial tear of the anterior talo – fibular ligament (“anterior sprain”)
- Grade 2: Complete tear of the ATF and partial tear to the calcaneofibular ligament
- Grade 3: Complete tear of the ATF and CF
- Grade 4: (some authors) posterior talo fibular ligament injury
Lateral ankle sprain radiographic evaluation
- The Ottawa ankle rules: who gets an x – ray ?
- Can not bear weight initially and / or
- Pain over syndesmosis or posterior malleolus
- AP, MO, Lat ankle and MO foot
- In the USA: everyone gets an x – ray !
Lateral ankle sprain associated injuries
- Ankle fracture
- Syndesmotic (“high”) ankle injury
- Shepard’s (Steida’s) fracture: posterior -lateral process of the talus
- Talar dome fracture
- Calcaneal anterior process fracture
- Fifth metatarsal base avulsion fracture
- Sinus tarsi syndrome
Rare associated injuries
- Pseudo aneurism of the lateral malleolar artery
- Neoplasm
- Compartment syndrome
- Reflex sympathetic dystrophy
- Achilles rupture
Calcaneal anterior process lateral injuries
- Avulsion injury via bifurcate ligament
Fifth met base avulsion fracture
- Avulsion from a lateral slip of the plantar fascia and to a lesser extent, the peroneus brevis
- Jones fracture uncommon
Talar dome fractures
- A common latent complaint
Lateral ankle sprain initial management
- Protection
- Rest
- Ice
- Compression
- Elevation
- NSAID’s ?
Lateral ankle sprains management (general/continuous)
- Jones compression for 0- 5 days
- Syndesmotic injury: wb immobilization 6 -8 weeks
- Limit the period of non – weight bearing
- CAM walker for early weight - bearing
- Consider bone scan / MRI / CT
- Begin rehabilitation ASAP
CAM walker
- Allows for early weight – bearing and maintains (ankle dorsiflexed) ATF in close approximation (less pain !)
Rehabilitation
- Acute phase
- Rehabilitative phase
- Functional phase
- Return to activity phase
Functional phase: improve strength and proprioception
- BAPS (biomechanical ankle platform system) board
- Plyometrics
- Toe raises / other balancing exercises
- Side – to – side lateral movement (slide board, shuttle machine)
- Cybex / Biodex
Return to activity phase
- Sport – specific movements
- Preventative strategies
- Equipment modifications