Talk:Ankle fracture

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Ankle Fractures Nicholas Manville SHO Trauma and Orthopaedics Ankle Fractures Radiography 2 classifications Specific fractures Treatment options Normal Anatomy Bones Talus Tibia Fibula Ligaments Lateral collateral ligaments Anterior talofibular ligament Calcaneofibular ligament Posterior talofibular ligament Medial deltoid ligament Lateral Ligaments Medial Ligaments Clinical Features Stumble over unexpected obstacle Fall from height Ankle twisted under leg Swelling and bruising appear rapidly Tenderness If both sides then injury to both sides (ligamentous or bony) must be suspected Ottawa Rules Normal Radiography AP Lateral Mortice Leg internally rotated 15-20º so beam nearly perpendicular to intermalleolar line Radiography Talocrural angle 83º+/-4º Radiography Medial joint space is less than 4 mm, with talar tilt less than 2mm (on mortice view) Interosseous clear space is less than 5mm (Chaput clear space) Overlap between anterior tibial tubercule and fibula is at least 10 mm Talocrural angle (normal is 83º+/-4º) Talar tilt (0º) Tibiotalar line both on AP and lateral radiographs must pass through the centre of the tibia and the centre of the talus Radiography (Cont.) After reduction the results are evaluated on a control x-ray Acceptable results are up to 2mm of residual displacement Especially for the fibular length Up to 0.5mm of talar displacement Lauge Hansen Classification

Pronation - abduction injuries 
Pronation-external rotation (eversion) injuries 
Supination - adduction injuries 
Supination - external rotation (eversion) injury 

Mechanism of Fractures If a malleolus is pushed off it fractures obliquely If a malleolus is pulled off it fractures transversely Eversion and external rotation  Oblique fracture (push) lateral malleolus Transverse fracture or ligament tear (pull) medial side Adduction / inversion  Medial malleolus oblique fracture (push) Lateral ligament tear / transverse fracture Pronation – Abduction Injuries Pronation of forefoot is combination of External rotation at ankle Abduction of hindfoot eversion of forefoot In pronation, the medial structures tighten and are injured first Associated injuries Dome fractures of the talus are common in this shearing fracture Sequence of Injury in Pronation – Abduction Injuries Avulsion fracture of medial malleolus or rupture of deltoid ligament (malleolus will have a transverse fracture)

Abduction force then either ruptures syndesmotic ligaments or avulses their bony attachment sites

Lateral force from talus impacts and fractures fibula at or above level of syndesmosis & ruptures interosseous membrane up to level of this fracture Fracture is either oblique or partially transverse Occasionally has a butterfly fragment, making it unstable Pronation – External Rotation Medial side is injured first Transverse fracture of medial malleolus or disruption of deltoid ligament External rotation then results in rupture of the anterior tibiofibular ligament or its bony insertion Short oblique or spiral fracture of fibula above the level of the joint Posterior injury tibiofibular ligament rupture or avulsion of posterior malleolus Supination - Adduction Injuries of the Ankle Equivalent to Weber type A fracture Transverse avulsion type fracture of the fibula (short oblique or transverse) below the level of joint or tear of the lateral collateral ligaments and vertical fracture of the medial malleolus Associated injuries osteochondral fracture of talus or injury to its articular surface Marginal impaction fractures Frequently does well with closed reduction Vertical Medial Malleolus Fracture Mechanism of Supination-adduction Injury Supination of foot is combination of inward rotation at ankle, adduction of the hindfoot, inversion of the forefoot As foot supinates the lateral structures tighten Continued supination & adduction force may rupture portions of lateral collateral ligaments or may avulse distal fibula Transverse fracture below the level of intact syndesmotic ligaments Subsequently, adduction forces talus against the medial side of the joint, resulting in vertical fracture of medial malleolus Supination External Rotation Ankle Injuries Equivalent of Weber B Rarely fracture may occur well above the syndesmosis so is not the equivalent of a Weber B frx Most common type of fracture of fibula Oblique fracture at the level of syndesmosis As supinated foot externally rotates (or leg internally rotates on planted, supinated foot), lateral structures and anterior syndesmotic ligaments tighten Characteristic posterior spike on the distal fragment With high energy injuries (such as parachute injuries), the spiral fibular fracture may begin somewhat higher than is seen with low energy injuries Weber vs. Lauge Hansen Type A = Supination-adduction Type B = Supination-eversion Type C = Pronation-eversion and pronation -abduction Danis-Weber A Fracture below the syndesmosis Usually involves a supination-adduction injury Since syndesmotic ligaments are intact, ankle mortise is stable

Sub-types

A1 isolated A2 with fracture of medial malleolus A3 with a posteromedial fracture Danis-Weber B Fracture at the syndesmosis Often associated with disruption of anterior fibres of tibiofibular ligament Analagous to Supination-external rotation injury Sub-types B1 isolated B2 with medial lesion (malleolus or ligament) B3 with a medial lesion and fracture of posterolateral tibia Danis Weber C Fibular fracture above syndesmosis Result from external rotation or abduction forces Disrupt the syndesmosis Usually associated with an injury to medial side Unstable Sub-types C1 diaphyseal fracture of the fibula, simple C2 diaphyseal fracture of the fibula, complex C3 proximal fracture of the fibula Principles of Treatment The treatment of ankle fractures can be conservative or operative Depends on Fracture type The state of the circulation Skin condition General condition of patient Possibility of complications Principles of Treatment Swelling is rapid and severe If fracture not reduced within a few hours treatment may need to be deferred for several days Fractures and fracture/dislocations should be reduced as soon as possible (i.E. In casualty) because gross displacement can lead to Impairment of the peripheral circulation Neurapraxia Ischaemic loss of skin All articular surfaces must be anatomically reconstructed, because any incongruity may lead to post-traumatic arthritis Principles of Treatment Reduction of the fracture must be maintained during the healing period Excessive external cast immobilisation has deleterious effects on cartilage Motion of the ankle should be instituted early to minimise effects of immobilisation Atrophy Contracture Synovial adhesions Cartilage degeneration Vascular changes with oedema Non-operative Treatment Closed reduction with cast immobilisation should be reserved for nondisplaced,stable fractures Anatomically reduced fractures Patients with poor medical condition Reduction is obtained by reversing the mechanism of injury Under general or spinal anaesthesia Knee in flexion Lower leg dropped down over the edge of the table Non-operative Treatment In view of the swelling and possibility of redisplacement a second x-ray should be taken at 48 h 7 days 14 days Two weekly intervals When the oedema subsides the reduction can be lost and then immediate surgery should be performed Non-operative Treatment Stable/non-displaced ankle injuries: Splint 3-5 days Thereafter short leg cast 4-6 wks Weight bearing after symptoms subside With rotational instability Use long leg cast with 15º knee flexion for 4-6 weeks, then short cast Delay weight bearing until evidence of healing Always avoid immobilisation of the ankle in equinus The fracture normally unites at 12–16 weeks

Surgical Indications
Displaced, unstable, lateral malleolar avulsion with soft tissue disruption

Failure to close the gap may lead to non union; Displaced fractures of medial joint complex, Vertical type medial malleolus fracture With or without fracture of posteromedial aspect of the tibia

 Osteochondral fracture of medial articular surface of tibia or talus

Contraindications to Surgery Infection Diabetes Paraplegia Elderly and sedentary patients Multiple life endangering injuries Observe ATLS guidelines Other considerations Timing After 21 days anatomic reduction frequently impossible to achieve Open Fractures Immediate internal fixation gives good functional results With antibiotics deep infections no more common 2% grade I 6% grade II 30% grade III Indicated in grade 1 and 2 injuries Isolated Fracture of One malleolus Often ligament on opposite side injured If displacement not marked then can be immobilised for 6 weeks Lateral malleolus Minimal displacement (<2mm)  good results with conservative management Displaced fractures may be fixed with 1/3 tubular plates +/- interfragmentary screws or tension-wiring Large, displaced medial fragment should be accurately reduced and internally fixed (long oblique screw) Fractures of Both Malleoli Below the Tibiofibular Joint Syndesmosis is intact Decision to treat surgically based on individual patitent, risks, post-reduction radiograph Closed reduction can be accurate Lateral malleolus is key and should be stabilised first Plate fixation on posterolateral border Otherwise risk of rotation and shortening  arthritis Large medial malleolar fragment may need open reduction and screws Fractures of Both Malleoli With Fibular Fracture Above the Tibiofibular Joint Unstable Always requires operative treatment Aim to restore length of fibula (fix with plate and screws) If medial malleolar fragment large will need screw If medial malleolus intact but talus tilted then medial collateral ligmament torn and needs repair Trimalleolar Fractures Bimalleolar fracture with fracture of posterior lip of tibia Internal fixation recommended if posterior fragment >25% of articular surface Eponymous Fractures Percival Pott (1768) Fibular fracture with deltoid ligament disruption Dupytren (1819) Bimalleolar fracture Maisoneuve (1840) Spiral fracture in proximal fibula caused by external rotation Tillaux (1872) Avulsion fracture of tibial insertion of anterior tibiofibular ligament Maisonneuve Fracture Proximal fracture of fibula resulting from external rotation Transmission of the force through the interosseous membrane which exits via a proximal fibular fracture Variations in pattern of fibula fracture reflecting either supination or pronation Foot may even move from relative pronation to supination during injury Maisonneuve Fracture Injury may occur with Medial malleolus avulsion fracture or deltoid ligament rupture Rupture of anterior talofibular ligament or avulsion of its insertion Rupture of interosseous lig, Rupture of posterior tibiofibular ligament, or posterior malleolar frx; Differential diagnosis

Proximal tibio-fibular dislocation

Treatment of Maisonneuve Fracture EUA for stability Stable fracture can be managed in long leg cast with frequent follow-up Unstable fracture requires fixation of syndesmosis No need to fix proximal fibula Short leg cast, non-weight bearing for 6 weeks Pilon Fractures Pilon Fractures Distal Tibial fractures Destaut (1911) Axial compression / high energy High complication rates (over 40%) with classical rigid internal fixation Infection Loss of skin coverage Amputation Pilon Fractures Suggestion of better results with dynamic external fixation followed by delayed internal fixation +/- Arthroscopy at 48-72 hours No place for primary arthrodesis Chronic cases treated with Arthrodesis Arthoplasty Salter-Harris Type Injuries 1/3 of these occur around ankle Usually results in Salter-Harris type 1 or 2 fracture Type 3 and 4 fractures are uncommon but dangerous Undisplaced physeal fractures are easily missed on x-ray and children with even a hint of physeal widening should be re-x-rayed in one week Treatment of type 1 and 2 injuries is usually closed Salter-Harris Type Injuries Type 3 or 4 injuries if undisplaced can be treated the same but must be x-rayed after 5 days Unless reduction perfect then fracture reduced open and fixed with 2 thin cancellous screws Removed after 4 months Post-op immobilisation in below knee cast for 4 weeks Salter-Harris Type Injuries Malunion may result in deformity (usually valgus) May correct under 10 years May require osteotomy Salter-Harris Type Injuries Assymetrical growth due to fusion of the epiphysis Bony bridge usually medial half of growth plate Distal tibia goes into varus CT useful Small bridge can be excised and replaced by fat pad Supramalleolar osteotomy may be required Shortening may require leg length equalisation Complications – Malunion More common than non-union Leads to pain and arthritis Main cause is failure of the fibular reduction Shortening and rotation of the fibula Results in lateral talar displacement Most authors advocate fibular osteotomy,distal advancement and derotation with bone graft and plate fixation Malunion of the medial malleolus is less common Incomplete reduction Narrowing of the anterior ankle joint results in talus impingement on the medial malleolar margin Osteotomy of the medial malleolus through the initial fracture line is performed with correction of its position and fixation Complications – Non-union Occurs most frequently at the medial malleolus after closed reduction Can be asymptomatic If painful, the site of non-union is freshened and fixed with a screw or a plate Bone graft is necessary for the lateral malleolus Complications – �Post-traumatic athritis More frequent radiologically (up to 30%) Some patients tolerate it well With pain an arthrodesis or athroplasty is indicated Complications – �Distal tibial synostosis Occurs after a fibular fracture or neglected tibiofibular disruption New bone formation occurs at site of major soft tissue injury Asymptomatic in most cases If painful an excision of the heterotopic bone can be performed with beneficial results Complications – Syndesmosis malunion This is characterised by a tibiofibular diastasis In most cases operative treatment is necessary Complications – Infection After open reduction and internal fixation infection occurs in about 1% of patients Culture from the wound or ankle aspiration must be done Options Superficial infection Only wound care and appropriate antibiotics are needed Deep ankle infection If the fixation device is loose it must be removed and the fracture is stabilised by an external fixator If the fracture site is secure, the fixation device is left in place until after fraction union Antibiotic treatment is maintained for another 4–6 weeks Complications – Wound Dehiscence Generally occurs over the lateral aspect of the ankle joint (lack of subcutaneous tissue) Sometimes difficult to close the wound after fixation Only therapeutic possibility is elevation of the extremity on an overhead frame Pillow elevation is insufficient Complications – �The Diabetic Foot Four times greater infection rate, even in patients treated nonoperatively 2-7x greater complication rate of operated ankle fractures compared to patients without diabetes Complications DVT / PE Compartment syndrome Algodystrophy Ongoing Pain Subtalar sprains Misdiagnosed tendon injuries around the ankle Osteochondral or synovial lesions which may be found during arthrosocopy Also the personality of the patient can explain some discrepancy between the radiological and clinical results Some symptoms of post-traumatic stress disorders (PTSD) may be found in trauma patients Treatment of Type A Fractures Non operative treatment If fibula is undisplaced / minimally displaced, & no medial lesion Walking cast until fibula has healed (usually 6-8 weeks) Surgical indications Displaced, unstable, lateral malleolar avulsion fracture with soft tissue disruption Failure to close the gap may lead to non union Displaced fracture of medial joint complex vertical type medial malleolus fracture +/- fracture of posteromedial aspect of the tibia osteochondral frx of medial articular surface of tibia or talus; Treatment of Type B Fractures Non-operative If no medial injury (stable) and <3mm fibular displacement then treatment with cast justified Operative Deltoid ligament injured if In presence of medial tenderness, > 5 mm of space is seen either initially or on a stress radiograph injury Treat as bimalleolar fracture ORIF of lateral malleolus Routine exploration of medial side of the ankle not indicated unless evidence that deltoid ligament blocking reduction Treament of Type C Lateral malleolar fracture It is essential that the fibula not be plated in a shortened position ?Take an x-ray of opposite ankle in order to judge exact length of fibula talocrural angle can be used to asses shortening Oblique fractures can be fixed with lag screw followed by neutralization plate Medial malleolus fractures Screws Syndesmotic injury Anatomic reduction of both the fibular and the medial malleolus fracture will usually restore the stability of the mortise If there is evidence of deltoid ligament disuption but no fracture, then syndesmotic fixation is usually required Outcome --Manville 22:32, 2 March 2007 (UTC)

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