1. Ankle – anatomy, soft tissue injuries & fractures

2. Aims
Anatomy
Fractures
Sprains
Other soft tissue injuries

3. Case 1 25 yr old male 2/52 post fall
Attended ED at time of injury – XR NBI
Ankle sprain card
Swelling now settled
Foot drop
Altered sensation dorsum of foot

4. Diagnosis A) Spinal/back injury B) Missed fracture
C) Soft tissue injury
D) Common peroneal nerve injury

5. Bony anatomy

6. Medial collateral ligaments
Ligament Anatomy
Medial collateral ligaments
Deltoid ligament
Composed of:
Post. tibiotalar
Tibiocalcaneal
Tibionavicular
Name on diagram

7. Lateral collateral ligaments
Anatomy
Lateral collateral ligaments
Ant. talofibular lig.
Calcaneofibular lig.
Post. talofibular lig.
Tibia-fibular ligaments
Ant. & post. tibiofibular ligaments
Intraosseous ligament
Inf. transverse ligament
Inferior transverse ligaments = supports posterior inferior portion of ankle joint
Interosseous ligament = lower portion of the interosseous membrane. Provides the strongest bond between the tibia and fibula at the joint

9. Muscles & tendons

10. Nerves & blood supply Vascular supply Nerves Sciatic nerve
Anterior & posterior tibial arteries and peroneal artery are continuations of the popliteal artery and supply ankle and foot.

11. Examination of ankle History important: Examination includes:
Mechanism of injury
Fracture more likely if unable to WB immediately after injury
Examination includes:
proximal fibula - calcaneum
both malleoli - Achilles tendon
navicular - base 5th metatarsal
neurovascular status -ankle movements
Mechanism e.g. Inversion vs eversion

12. Ottawa ankle rules
Combined results give sensitivity 97.8% and specificity 31.5% for excluding fractures
In 1992, Emergency Medicine group at the University of Ottawa evaluated clinical findings in ankle and midfoot injuries. The only clinical aspects with inter-rater reliability now form the Ottawa ankle and foot rules.
i.e. unable to WB for 4 steps both immediately after injury and in the dept, bony tenderness post. edge both malleoli, navicular or base 5th MT.
Ankle rule gives sensitivity of 98% & specificity of 40% for excluding fractures based on the initial study and several validation studies.
Article in BMJ states that 15% of ankle injuries are fractures. Therefore there is a pre test probability of 15% gives a post test probability of < 1% if the test is negative or 22% if the test is positive. Therefore, X-ray not required if test negative.

13. Fractures Ankle = mortice joint Always look for talar shift
Mortice joint formed by talus, fibula, tibia, ligaments & distal tibio-fibular syndesmosis. Allows very little rotation or angulation at this joint so any severe force causes fracture/ligament disruption/disruption of the syndesmosis.

14. AO/Weber classification
Type A
# fibula below syndesmosis
Conservative mx if undisplaced & no medial #
Refer if # medial malleolus

15. AO/Weber classification
Type B
# at level of syndesmosis
May be associated with # or ligamentous injury to medial side or posterolateral tibia
Refer Ortho as rarely treated conservatively
Type B – most common. Usually oblique #.

16. AO/Weber classification
Type C
above the syndesmosis
Also includes # of proximal fibula in this classification
Need ORIF

17. Fractures
Bimalleolar fracture
Align and repeat X-Ray post back-slab

18. Trimalleolar fracture
Fractures
Trimalleolar fracture
Fracture of:
Medial malleolus
Lateral malleolus
Posterolateral tibia
Unstable
Also called ‘Cotton fracture’

19. Fractures Pilon fracture
Distal tibial metaphyseal including medial malleolus
75% have lateral malleoli #
Consider other related fractures
‘Pilon’ means pestle in French – crush/pound – talus driven into tibia. Usually fall from height or RTA with foot on pedal.
Related #’s = calcaneum, vertebral compression, acetabulum, tibial plateau

20. Fractures Maisonneuve fracture
# medial malleolus plus # proximal fibula
Patient may not complain of pain due to fibular # so examine specifically for it
- Results from external rotational force to ankle with transmission through interosseous membrane and exits thru prox fibula #.
Usually don’t need to fix the fibular #
Maisonneuve was a doctor who described the fracture in 1840

21. Talar avulsion fracture
Fractures
Talar avulsion fracture
Mechanism similar to ankle sprain
Focal pain & swelling
Conservative mx unless large fragment
Don’t confuse with the os trigonum

22. Talar avulsion fractures

23. Posterior dislocation
Ankle dislocation
Posterior dislocation
Most common type
Talus moves posteriorly in relation to tibia
Talus wider anteriorly so joint space pushed apart or # lat. malleolus

24. Ankle dislocation Management: Orthopaedic emergency
Assess skin and neurovasc status
Reduction precedes X-Ray
Adequate analgesia or sedation
Repeat X-Ray post reduction

25. Ankle sprain Grade 1 = stretching or minor tear Grade 2 = partial tear
Grade 3 = complete tear
90% involve lateral ligaments
5% deltoid ligament
5% ATFL or PTFL
Lateral ligaments – tear in sequence from anterior to posterior. So anterior talofibular ligament first then calcaneofibular lig then rarely the post talofibular ligament. Anterior drawer test will be positive if first two are ruptured.
Anterior drawer test –if talus moves anteriorly more than 3mm then may be significant but if more than 1cm then definitely significant!
The posterior talofibular ligament is usually only ruptured when associated with ankle dislocation. There will also be talar shift if this ligament is ruptured.
Deltoid ligament – almost impossible to tear without fracture of fibula or disruption of tibio-fibular syndesmosis. Usually an eversion injury.

26. Stability
Anterior drawer test –if talus moves anteriorly more than 3mm then may be significant but if more than 1cm then definitely significant
Lateral ligaments – tear in sequence from anterior to posterior. So anterior talofibular ligament first then calcaneofibular lig then rarely the post talofibular ligament. Anterior drawer test will be positive if first two are ruptured

27. Ankle sprain - management
Rest, ice, elevation
Advice leaflet with exercises
Refer physio if severe
Consider immobilisation if struggling (3/12 improved by 9/12 no difference (lancet ‘09))
Rehab ROM, strength & proprioception
Functional tests for return to sport
-Need to assess for ligamentous laxity but impossible when present acutely. If severe, refer physio or bring back to clinic and can assess then.
-Recent study by CAST group (Lancet 2009) randomised those with ankle sprain to tubigrip, cylinder cast, Aircast boot or another type of boot. Those immobilised were better at 3 months but by 9 months there was no difference. There was a 25% dropout rate in each group which will have affected results.
-Article in BMJ in ‘98 – approx 600,000 ankle sprains to ED/year – approx 50cm length per patient – 600km of tubigrip/yr of doubled up so cost of £654,000!!!!

28. Ankle sprains - complications
Instability:
refer physio
Peroneal nerve injury:
neuropraxia due to stretching of branches or nerve at time of injury
reduced sensation on dorsum of foot
reduced proprioception (articular branches)
Peroneal tendon subluxation:
Clicking & sense of something slipping
Reproduce it if move ankle especially eversion
Instability- presents as recurrent sprains.

29. Other soft tissue injuries
Achilles tendon rupture
Usually due to sudden forceful contraction of the calf muscle
Describe sudden sharp blow/pain to back of ankle
Pain, swelling, bruising & often palpable gap in tendon
Simmonds test positive
May still be able to plantarflex foot
Occasionally partial tear so if suspect, bring back for USS
Plaster/boot with foot in equinus
Cochrane review – BK plaster
-Usually 5cm above the calcaneal insertion
-May still plantarflex due to action of tibialis posterior, peroneal and toe flexor muscles.

30. Other soft tissue injuries
Achilles tendonitis & Tennis calf
Usually hx of unaccustomed activity or overuse
Localised pain, swelling & palpable crepitus
Treat with NSAIDS, rest for 2 days then exercise as pain allows. Heel pad may help.
Achilles – Greek hero of the Trojan war. Invulnerable apart from his heel. Died from poisoned arrow shot into his heel.

31. Any questions?