Tib, Fib, Ankle Flashcards
4 ligaments that compose the syndesmotic ligament complex:
1: anterior inferior tibiofibular ligament
2: posterior inferior tibiofibular ligament (thicker and stronger than anterior)
3: transverse tibiofibular ligament (inferior to posterior)
4: interosseous ligament (distal continuation of the interosseous membrane)
Components of the deltoid ligament complex:
Superficial: originate on the anterior colliculus
1: tibionavicular ligament (suspends the spring ligament)
2: tibiocalcaneal ligament (prevents valgus displacement)
3: talotibial ligament (most prominent of the 3)
Deep: deep anterior and posterior tibiotalar (primary medial stabilizer against lateral displacement)
3 ligaments of the fibular collateral ligament
Anterior talofibular, posterior talofibular, calcaneofibular
Radiographic eval of ankle injuries:
AP, Lateral, and mortise view
Indication of medial or lateral joint disruption with Talar Tilt
Difference in width of the medial and lateral aspects of the superior joint space >2 mm
Positioning of the foot to take mortise view X-ray
Foot in 15-20 degrees of internal rotation (to offset the intermalleolar axis)
The tibiofibular clear space should be less than how many mm?
6 mm
Approximate degrees of the talocrural angle
83 +- 4 degrees (from picture); or between 8 and 15 degrees (angle subtended bt the intermalleolar line and a line parallel to the distal tibial articular surface. Angle should be between 2 to 3 degrees of uninjured ankle.
Medial clear space should be equal to the superior clear space between the talus and the distal tibia and less than how many degrees on standard X-ray
Less than or equal to 4 mm; greater than 4 indicates lateral talar shift
Classification system used for rotational ankle fractures
Lauge-Hansen (takes into account 1: the position of the foot at the time of injury, and 2: the direction of the deforming force)
4 possible position-direction of force combinations with the Lauge-Hansen classification system
Supination-adduction
Supination-external rotation
Pronation-adduction
Pronation-external rotation
Stages of supination-adduction with lauge-Hansen
Stage 1: transverse avulsion type fx of the fibula distal to the level of the joint or a rupture of the lateral collateral ligaments
Stage 2: vertical medial malleolar fx
Stages of supination-external rotation (40-75% of malleolar fxs)
Stage 1: anterior tib-fib sprain +- avulsion fx
Stage 2: typical spiral/short oblique fx of distal fibula
Stage 3: disruption of post tibfib ligament or fx of post malleolus
Stage 4: transverse avulsion fx of medial malleolus or rupture of deltoid ligament
Stages of pronation-external rotation
Stage 1: transverse fx of medial malleolus or rupture of deltoid lig
Stage 2: disruption of the ant tibfib lig +- avulsion fx at insertion site, Chaput’s tubercle
Stage 3: spiral fx of distal fib at or above syndesmosis; medial injury with high fib fx
Stage 4: rupture of post tibfib lig or avulsion fx of posterolateral tibia
Stages of pronation-adduction with lauge-Hansen classification of rotational ankle fractures
Stage 1: transverse fx of medial malleolus or rupture of deltoid lig
Stage 2: rupture of syndesmotic lig or avulsion fx at their insertion sites
Stage 3: transverse or oblique fx of distal fibula at or above level of syndemsosis, producing lateral comminution or butterfly fragment
Fx classification based on the level of the fibular fracture
Danis-Weber (more proximal the fx, the greater risk of syndesmotic injury
Maisonneuve fx:
Ankle injury with a fx of the proximal third of the fibula. This is a pronation-external rotation type injury
Curbstone fx
Avulsion fx off the posterior tibia 2/2 tripping mechanism
Maisonneuve fx:
Ankle injury with a fx of the proximal third of the fibula. This is a pronation-external rotation type injury
LeForte-Wagstaffe fx
Anterior fibular tubercle avulsion fx by ant tibiofibular lig, usually associated with LH SER type fx pattern
Tillage-Chaput fx
Avulsion of the ant tibial margin by the ant tibiofibular lig is the tibial counterpart of the LeForte-Wagstaffe
Classic sign for posterior colliculus fx on external rotation view
Supramalleolar spike
Indications for Nonoperative tx of ankle fxs: 3
1: nondisplaced, stable fx with intact syndesmosis
2: displaced fx for which stable anatomic reduction of the ankle mortise is achieved
3: unstable, multiple trauma pt
Operative tx for lateral malleolar fxs distal to the syndesmosis
Lag screw or kirschner wires with tension banding
Operative tx of lateral malleolar fxs at or above the syndesmosis
Combination of lag screws and plate (important to restore length and rotation)
Indications for operative fixation of medial malleolus fx (4)
1: concomitant syndesmotic injury
2: persistent widening of the medial clear space following fibula reduction
3: inability to obtain fibular reduction
4: persistent medial fx displacement after fibular fixation
Operative tx of medial malleolar fxs
Stabilized with cancellous screws or figure of eight tension banding
Indications for fixation of posterior malleolus fx (3):
1: involvement of >25% of the articular surface
2: >2mm displacement
3: persistent posterior subluxation of the talus
Operative tx for posterior malleolus fx:
Anterior to posterior lag screw or posteriorly placed plate and/or screws
Placement of a syndesmotic screw for stabilization
1.5 to 2.0 cm above the plafond from the fibula to the tibia. Note: either 3 or 4 cortices and either 3.5 or 4.5 mm screws
Loss of reduction is reported in what % of unstable ankle injuries treated nonoperatively?
25%
Classification for Pilon (plafond) fxs
Ruedi and Allgower
Ruedi and Allgower classification:
Type 1: nondisplaced cleavage fracture of the ankle joint
Type 2: displaced fracture with minimal impaction or comminution
Type 3: displaced fx with significant articular comminution and metaphyseal impaction
Goals of operative fixation of Pilon fxs: 4
1: Maintenance of fibula length and stability
2: restoration of tibial articular surface
3: bone grafting of metaphyseal defects
4: stabilizing of the distal tibia
Surgical tx for Pilon fxs
ORIF with plate fixation after use of initial spanning external fixation. Avoid incisions of the anteromedial tibia. Use small, precontoured, low profile mini frag screws. Percutaneous approach for plate insertion.
Classification system names (2) for tibial plateau fxs
Schatzker and Moore
Schatzker classification system of tibial plateau fractures
Type 1: lateral plateau, split fx
Type 2: lateral plateau, split depression fx (most common)
Type 3: lateral plateau, depression fx
Type 4: medial plateau fx
Type 5: bicondylar plateau fx
Type 6: plateau fx with separation of the metaphysis from the diaphysis
Moore classification system
Type 1: split fx of the medial tibial plateau in the coronal plane
Type 2: entire condyle fx with the fx line beginning in the opposite compartment and extending across the tibial eminence
Type 3: rim avulsion fx (high rate of neurovascular injuries)
Type 4: rim compression injury associated with contra lateral ligamentous injury
Type 5: four part fx with the tibial eminence separated from the tibial condyles and the shaft
Surgical tx for Schatzker types 5 and 6
Plate and screw, ring fixator, or a hybrid fixator.
Surgical Tx for Schatzker types 1 through 4
Percutaneous screws or laterally placed periarticular plate; depressed segments should be fixed using a bone tamp
Long bone fx with the overall highest rate of nonunion
Tibial shaft
Most common locations (2) for tibial stress fxs area where sclerosis is most noticeable? What is a Radiographic sign that is pathognomonic for stress fxs?
Metaphyseal-diaphyseal junction in military recruits and middle third of shaft in ballet dancers. Sclerosis most marked at Posteromedial cortex in metaphyseal-diaphyseal fxs. “Dreaded black line” is pathognomonic
Plain Radiographic findings are often delayed for weeks with stress fxs. What imaging is very sensitive for detecting stress fxs early?
MRI
Most reliable sign of compartment syndrome
Pain out of proportion to injury
Compartment pressure measurements indicating compartment syndrome
Pressure within 30 of diastolic pressure
Gustilo and Anderson classification of open fractures
Type 1: clean skin opening 1 cm long, simple transverse or short oblique fxs
Type 2: 1 cm to 10 cm with extensive soft tissue damage, minimal to moderate crushing component, simple transverse or short oblique fxs with minimal comminution
Type 3: extensive soft tissue damage (>10 cm laceration), including muscles, skin, and neurovascular structures, high energy injury with severe crushing component
3A: extensive soft tissue laceration, adequate bone coverage, minimal periosteal stripping
3B: extensive soft tissue with periosteal stripping and bone exposure requiring soft tissue flap closure, massive contamination
3C: vascular injury requiring repair
Isolated injuries to the lateral plateau of the tibia are the most common tibial plateau fracture. What percentage?
55-70% of tibial plateau fractures
Fractures involving the medial tibial plateau may be associated with higher incidences of these two types of injuries owing to higher-energy mechanisms
Peroneal nerve and popliteal neurovascular lesions
Radiographic eval for tibial plateau fractures
AP and lateral view supplemented by 40 degree internal (lateral plateau) and external rotation (medial plateau); a 10 to 5 degree caudally tilted plateau view can be used to assess articular step off
What are 3 additional signs of ligamentous injury seen in tibial plateau fractures?
Avulsion of the fibular head, the Segond sign (lateral capsular avulsion) and Pellegrini-Steata lesion (calcification along the insertion of the MCL)
Treatment of nondisplaced or minimally displaced tibial plateau fractures; also for severe osteoporosis
Non-op: protected weight bearing, quad strengthening, progressive passive, active-assisted, and active ROM exercises; partial weight bearing (30-50 lbs) for 8-12 weeks
Use of spanning external fixation in tibial plateau fractures:
Temporizing measure to keep soft tissues out to length and provide some degree of fx reduction until definitive surgery
Operative treatment principles in tibia fxs, the goal of reconstruction:
Reconstruction of the articular surface, followed be reestablishment of tibial alignment
Role of arthroscopy in tibial plateau fxs:
Arthroscopy may be used to evaluate the articular surfaces, the menisci, and the cruciate ligaments; evacuation of hemarthrosis
Most common long bone fractures
Tibia and Fibula shaft
The nutrient artery of the tibia arises from what artery
Posterior tibial artery - nutrient artery enters the posterolateral cortex distal to the origination of the soleus muscle
Poor sensitivity, reproducibility, and interobserver reliability have been reported for most classification systems - what are the descriptive parameters for tibial shaft fxs
Open vs closed; Location: prox, mid, distal third
Frag number and position: comminution, butterfly frags
Configuration: transverse, spiral, oblique
Angulation: varus/valgus, anterior/posterior
Shortening, rotation
Displacement: % of cortical contact
Satisfactory closed reduction of tibial plateau fx
Less than 1 mm step off
Surgical indications of tibial plateau fxs (5)
1: reported range of articular depression that can be accepted varies from less than 2 mm to 1 cm
2: instability greater than 10 degrees of the nearly extended knee compared to the contralateral side
3: open fxs
4: associated compartment syndrome
5: associated vascular injury
Tscherne Classification of Closed Fxs: classifies soft tissue injury in closed fxs and takes into account indirect versus direct injury mechanisms
Grade 0: Injury from indirect forces with negligible soft tissue damage
Grade I: Closed fx caused by low-moderate energy mechanisms, superficial abrasions or contusions of soft tissue overlying the fx
Grade II: Closed fx with significant muscle contusion, with possible deep, contaminated skin abrasions associated with moderate to severe energy mechanisms and skeletal injury; high risk for compartment syndrome
Grade III: Extensive crushing of soft tissues, subq degloving/avulsion, arterial disruption or established compartment syndrome
Non-op tx for isolated, closed, low energy fxs with minimal displacement and comminution
Fx reduction followed by application of a long leg cast with progressive weight bearing: Cast with knee in 0-5 degrees of flexion; after 3-6 weeks long leg cast replaced with patella-bearing cast or fx brace
Major limitation seen following non-op tx for tibial shaft fxs
Hindfoot stiffness following casting/bracing
Average time to union of tibia/fibula shaft fxs
16 +/- 4 weeks; delayed union = >20 weeks
Radiographic signs of nonunion and time parameter for nonunion
Radiographic: sclerotic ends at fx site and persistent gap unchanged for several weeks. Lack of healing 9 months after fx
Operative tx of tibia shaft fxs (4)
1: IM nailing - preservation of periosteal blood supply, controls alignment, translation, and rotation.
2: Flexible nails: not really used in US, recommended only in children with open physes
3: Ex Fix
4: Plate and screws: generally reserved for fxs extending into the metaphysis or epiphysis
When using IM nailing for tibia fxs you can use locked or nonlocked nails as well as reamed vs unreamed nails. Describe
Locked: rotational control, prevents shortening in comminuted fxs or with significant bone loss
Nonlocked: allows impaction at fx site, difficult to control rotation
Reamed: excellent IM splinting; larger, stronger nail
Unreamed: preserve IM blood supply in open fxs with periosteal stripping; reserved for higher grade open fxs
Why are Prox tib fxs a pain? (same problem with distal tib)
Difficult to nail - become malaligned, commonly valgus and apex anterior angulation; can use perq plate to counteract or blocking screws
Most common complication associated with IM tibial nailing
Knee pain
Radiographic signs of Reflex Sympathetic Dystrophy following Tibia fxs - most common in pts unable to bear weight early and with prolonged cast immobilization
Spotty demineralization of foot and distal tibia and equinovarus ankle
Muscle death occurs after how long with compartment syndrome
6-8 hours
This is associated with scarrign of extensor tendons or ischemia of posterior compartment muscles
Claw toe deformity
Most common location for neurovascular injury with tibial fractures
Occurs as the anterior tibial artery traverses the interosseous membrane of the proximal leg
Radiographic eval: injuries about the ankle - 3 indications of syndesmotic injury on AP xray;
Indication of medial or lateral disruption on AP:
Tibiofibula overlap of less than 10 mm; Tibiofibula clear space greater than 5 mm is abnormal = syndesmotic injury.
Talar tilt: difference in width of the medial and lateral aspects of the superior joint space > 2 mm is abnormal
This displaced fx off the anterior articular surface is considered a pilon variant when there is a significant articular fragment
Pronation-dorsiflexion fx
Closed fracture reduction for displaced fractures helps to minimize these four things:
Minimizes post-injury swelling, pressure on the articular cartilage, lessens the risk of skin breakdown, and minimizes pressure on the neurovascular structures
Indications for ORIF of rotational ankle fractures (4)
Failure to achieve or maintain closed reduction with amenable soft tissue, Unstable fx that may result in talar displacement or widening of the ankle mortise, Fractures that require abnormal foot positioning to maintain reduction (extreme plantar flexion), Open fxs
Articulating vs nonarticulating spanning Ex fix for pilon fxs
Nonarticulating (rigid): most commonly used, allows no ankle motion. Articulating allows motion in sagittal plane, which prevents ankle varus and shortening. Theoretically, articulating results in improved chondral lubrication and nutrition owing to ankle motion.
Post op mgmt of Pilon fxs
Initial splint placement in neutral dorsiflexion; early ankle and foot motion when wounds and fixation allow; non-weight bearing for 12-16 weeks, then progression to full weight bearing once there is radiographic evidence of healing.
Edwards and DeLee classification for syndesmosis sprains:
Type 1: Diastasis involves lateral subluxation w/o fx
Type 2: involved lateral subluxation with plastic deformation of the fibula
Type 3: posterior subluxation/dislocation of the fibula
Type 4: Superior subluxation/dislocation of the talus within the mortise
Two clinical tests that can be used to isolate syndesmotic ligament injury
Squeeze test and External rotation stress test
Acceptable fracture reduction of Tibial shaft fractures - 6
- Less than 5 degrees of varus/valgus angulation
- Less than 10 degrees of anterior/posterior angulation (less than 5 is preferred)
- Less than 10 degrees of rotational deformity. ER better tolerated than IR
- Less than 1 cm of shortening
- More than 50% cortical contact
- Roughly, the ASIS, center of patella, and base of second prox phalanx should be colinear
