AnkleX-Rays

X-Ray Rounds: (Plain) Radiographic Evaluation of the Ankle : 

X-Ray Rounds: (Plain) Radiographic Evaluation of the Ankle Garry W. K. Ho, M.D. VCU / Fairfax Family Practice Sports Medicine Fellow September 2006

Anatomy : 

Anatomy Complex hinge joint Articulations among: Fibula Tibia Talus Tibial “plafond” Distal tibial articular surface Complex ligamentous system

Anatomy : 

Anatomy Medial malleolus Distal tibia Medial support Lateral malleolus Distal fibula Lateral support Talus Trapezoid-shaped Mortise (tibial plafond, medial & lateral malleoli) - Constrained articulation with the talar dome

Anatomy : 

Anatomy Syndesmotic ligament complex Axial, rotational, & translational stability Four ligaments: Anterior tibiofibular ligament Posterior tibiofibular ligament Transverse tibiofibular ligament Interosseous ligament

Anatomy : 

Anatomy Deltoid (medial) ligament complex Superficial (contributes little to stability) Tibionavicular ligament Tibiocalcaneal ligament Superficial Tibiotalar ligament Deep (primary medial stabilizer) Intraarticular: Deep tibiotalar ligament

Anatomy : 

Anatomy Lateral (fibular collateral) ligament complex Anterior talofibular ligament (weakest) Posterior talofibular ligament (strongest) Calcaneofibular ligament

Indications for Ankle Radiographs : 

Indications for Ankle Radiographs Ottawa Ankle Rules Age 55 years or older

Indications for Ankle Radiographs : 

Indications for Ankle Radiographs How good are the Ottawa Rules? When originally published: 100% sensitivity & 40% specificity for detecting malleolar fractures Subsequent studies: Lower sensitivity (93% to 95%) and specificity (6% to 11%) than originally thought Not perfect, but still a good tool Other indications The patient cannot communicate (altered mental status, alcohol intoxication, or other) Pain and swelling do not resolve within 7-10 days after injury Anytime your history and physical don’t give you enough information

Slide 9: 

Normal ankle (AP view) Normal ankle (Mortise view) Normal ankle (Lateral view)

AP View of the Ankle : 

AP View of the Ankle DE: Talar Tilt: < 2 degrees of angulation is Nl D E

AP View of the Ankle : 

AP View of the Ankle Talar Tilt: > 2 degrees angulation may indicate medial or lateral disruption Tib-fib Clear Space > 5mm or Tib-fib Overlap < 10mm may indicate syndesmotic injury

Lateral View of the Ankle : 

Lateral View of the Ankle Dome of the talus: centered under and congruous with tibial plafond Posterior tibial tuberosity fractures & direction of fibular injuries can be identified Avulsion fractures of the talus by the anterior capsule can be identified Any deformity to the talus, calcaneus or subtalar joint

Calcaneal Fractures : 

Calcaneal Fractures Bohler’s Angle 30-35 degrees is normal Others: Critical Angle of Gissane Broden’s Views

Mortise View of the Ankle : 

Mortise View of the Ankle AP view taken with the foot in 15-20 degrees of internal rotation to offset the intermalleolar axis Medial clear space > 4mm may indicate lateral talar shift Talar tilt, Tib-fib Overlap, Tib-fib clearspace (see AP view) Talocrural angle (angle b/w plafond parallel and intermalleolar line) Normal is 8-15 degrees (where the lines intersect) Smaller angle may indicate fibular shortening

Mortise View of the Ankle : 

Mortise View of the Ankle

Slide 16: 

mm Normal AP & lateral right ankle X Ray

Slide 17: 

mm AP View: Widened medial clear space Mortise View: Open mortise (decreased tib-fib overlap) = Syndesmotic injury = Surgical referral (“needs a screw”)

Slide 18: 

28 y/o M who “twisted” his left ankle while playing basketball 1 day ago Danis-Weber Type B fibular ankle fracture

Ankle Fracture Classification : 

Ankle Fracture Classification Danis-Weber Classification Defined by location of the fracture line Type A: below the tibiotalar joint Type B: at the level of the tibiotalar joint Type C: above the tibiotalar joint Syndesmotic ligament compromise Lauge-Hansen Classification Infrequently used, clinically; mostly academic

Slide 20: 

mm Mortise view: Weber C fracture with open mortise and widened medial clear space = deltoid & syndesmotic ligament tears, with fracture = surgical referral

Slide 21: 

mm 25 y/o volleyball player “landed wrong” on the right foot, “hurting” the ankle Exam with positive talar tilt Lateral ligament tears ATFL -CFL

Radiographic Stress Tests of the Ankle : 

Radiographic Stress Tests of the Ankle Talar Tilt Stress Test Stabilize the leg with one hand while inverting plantar flexed heel with the other Contralateral ankle used for comparison Line is drawn across the talar dome and tibial vault Degree of lateral opening angle is measured Normal tilt is less than 5 deg Standing Talar Tilt Stress Test: may be more sensitive Patient stands on an inversion stress platform with the foot and ankle in 40 deg of plantar flexion and 50 deg of inversion

Slide 23: 

Grade III ATFL ankle sprain 25 y/o male tennis player “torqued” his right ankle Exam with positive anterior drawer sign

Radiographic Stress Tests of the Ankle : 

Radiographic Stress Tests of the Ankle Anterior Drawer Test Abnormal anterior translation is between 5 to 10 mm, or 3 mm more than other side External Rotation Stress Test Evaluates syndesmotic & deep Deltoid ligaments Difference in width of superior clear space between medial and lateral side of the joint should be < 2 mm

Slide 25: 

mm AP View: Widened medial clear space Decreased tib-fib overlap = Medial & syndesmotic ligament compromise = surgical referral

Slide 26: 

mm Normal AP & lateral views Open mortise = “needs a screw”

Slide 27: 

mm Weber Type A lateral malleolar fracture Treat conservatively

Slide 28: 

mm Open mortise with high fibular fracture Name? Maissoneurve fracture = surgical referral

Slide 29: 

mm Salter-Harris fracture, type II = Refer for ORIF

Slide 30: 

S A L T ER Straight Above beLow Through CERush 1 2 3 4 5

Slide 31: 

mm Lateral ligamentous injury Medial malleolar avulsion fracture Surgical referral

Slide 32: 

mm Nondisplaced spiral fibular fracture = CR & immobilization

Slide 33: 

mm Posterior malleolar avulsion fracture

Slide 34: 

mm Abnormal Bohler’s angle = Calcaneal Fx “Surgerize!”

Slide 35: 

mm Medial malleolar fracture = refer for screw fixation

Slide 36: 

mm Medial malleolar Fx Widened medial clear space: talar dislocation Open mortise: syndesmotic injury Maissoneurve Fx = Surgery

Slide 37: 

mm Bimalleolar fractures Osteopenic appearing bone Surgical referral Tx osteoporosis prn

Slide 38: 

mm Diagnosis? Charcot’s foot

Slide 39: 

mm Anterolateral tibial epiphyseal fracture aka: Tillaux fracture

Tillaux Fracture : 

Tillaux Fracture Fracture of the anterolateral tibial epiphysis Mechanism Avulsion of epiphyseal fragment due to the strong anterior tibiofibular ligament External rotational force across the ankle Commonly seen in adolescents Treatment: ORIF

Slide 41: 

mm Calcaneal osteomyelitis = IV Abx = Surgical I & D if chronic

Slide 42: 

mm Calcaneal fracture = ORIF

Slide 43: 

mm Mortise view AP view Lateral view Pilon fracture (Comminuted tibial plafond compression fracture) Management?

Slide 44: 

mm Positive talar tilt stress test Surgery

Slide 45: 

s/p Fall while rockclimbing Treatment ?

Conclusion : 

Conclusion Plain radiographic anatomy of the ankle Indications for plain radiographs of the ankle Direct and indirect signs of injury on plain radiographs

Slide 47: 

The End Thanks!