TRAUMA 2023, Jan, 22 | 12:00 am

INJURIES ABOUT THE ANKLE

  • INJURIES ABOUT THE ANKLE

     

     

     

     

    ROTATIONAL ANKLE FRACTURES

    Epidemiology

  • Population-based studies suggest that the incidence of ankle fractures has increased dramatically since the early 1960s.

  • The highest incidence of ankle fractures occurs in elderly women, although fractures of the ankle are generally not considered to be “fragility” fractures.

  • Most ankle fractures are isolated malleolar fractures, accounting for two-thirds of fractures, with bimalleolar fractures occurring in one-fourth of patients and trimalleolar fractures occurring in the remaining 5% to 10%.

  • The incidence of ankle fractures is approximately 187 fractures per 100,000 people each year.

  • Open fractures are rare, accounting for just 2% of all ankle fractures.

  • Increased body mass index is considered a risk factor for sustaining an ankle fracture.

    Anatomy

  • The ankle is a complex hinge joint composed of articulations among the fibula, tibia, and talus in close association with a complex ligamentous system (Fig. 38.1).

     

     

     

  • The distal tibial articular surface is referred to as the “plafond,” which, together with the medial and lateral malleoli, forms the mortise, a constrained articulation with the talar dome.

  • The plafond is concave in the anteroposterior (AP) plane but convex in the lateral plane. It is wider anteriorly to allow for congruency with the wedge-shaped talus. This provides for intrinsic stability, especially in weight bearing.

  • The talar dome is trapezoidal, with the anterior aspect 2.5 mm wider than the posterior talus. The body of the talus is almost entirely covered by articular cartilage.

  • The medial malleolus articulates with the medial facet of the talus and divides into an anterior colliculus and a posterior colliculus, which serve as attachments for the superficial and deep deltoid ligaments, respectively.

  • The lateral malleolus represents the distal aspect of the fibula and provides lateral support to the ankle. No articular surface exists between the distal tibia and fibula, although there is some motion between the two. Some intrinsic stability is provided between the distal tibia and fibula just proximal to the ankle where the fibula sits between a broad anterior tubercle and a smaller posterior tubercle of the tibia. The distal fibula has articular cartilage on its medial aspect extending from the level of the plafond distally to a point halfway down its remaining length.

  • The syndesmotic ligament complex exists between the distal tibia and fibula, resisting axial,

    rotational, and translational forces to maintain the structural integrity of the mortise. It is composed of four ligaments, including:

    • Anterior inferior tibiofibular ligament

    • Posterior inferior tibiofibular ligament (PITFL). This is thicker and stronger than the anterior counterpart. Therefore, torsional or translational forces that rupture the anterior tibiofibular ligament may cause an avulsion fracture of the posterior tibial tubercle, leaving the posterior tibiofibular ligament intact.

    • Inferior transverse tibiofibular ligament (inferior to posterior tibiofibular)

    • Interosseous ligament (distal continuation of the interosseous membrane) (Fig. 38.2)

       

       

       

  • The deltoid ligament provides ligamentous support to the medial aspect of the ankle. It is separated into superficial and deep components (Fig. 38.3).

    • Superficial portion: This is composed of three ligaments that originate on the anterior colliculus but add little to ankle stability.

      Naviculotibial ligament: This suspends the spring ligament and prevents inward displacement

      of the talar head.

      Tibiocalcaneal ligament: This prevents valgus displacement. Superficial tibiotalar ligament.

      Talotibial Ligament: This is the most prominent of the three.

    • Deep portion: This intra-articular ligament (deep tibiotalar) originates on the intercollicular groove and the posterior colliculus of the distal tibia and inserts on the entire nonarticular medial surface of the talus. Its fibers are transversely oriented; it is the primary medial stabilizer against lateral displacement of the talus.

       

       

       

  • The fibular collateral ligament is made up of three ligaments that, together with the distal fibula, provide lateral support to the ankle. The lateral ligamentous complex is not as strong as the medial complex (Fig. 38.4).

    • Anterior talofibular ligament: This is the weakest of the lateral ligaments; it prevents anterior subluxation of the talus primarily in plantar flexion.

    • Posterior talofibular ligament: This is the strongest of the lateral ligaments; it prevents

      posterior and rotatory subluxation of the talus.

    • Calcaneofibular ligament: This is lax in neutral dorsiflexion owing to relative valgus orientation of calcaneus; it stabilizes the subtalar joint and limits inversion; rupture of this ligament will cause a positive talar tilt test.

       

       

       

  • Biomechanics

    • The normal range of motion (ROM) of the ankle in dorsiflexion is 30 degrees, and in plantar flexion it is 45 degrees; motion analysis studies reveal that a minimum of 10 degrees of dorsiflexion and 20 degrees of plantar flexion are required for normal gait.

    • The axis of flexion of the ankle runs between the distal aspect of the two malleoli, which is externally rotated 20 degrees compared with the knee axis.

    • A lateral talar shift of 1 mm will decrease surface contact by 40%; a 3-mm shift results in >60%

      decrease.

    • Disruption of the syndesmotic ligaments may result in decreased tibiofibular overlap. Syndesmotic disruption associated with fibula fracture may be associated with a 2- to 3-mm lateral talar shift even with an intact deep deltoid ligament. Further lateral talar shift implies medial compromise.

      Mechanism of Injury

      The pattern of ankle injury depends on many factors, including mechanism (axial vs. rotational loading); chronicity (recurrent ankle instability may result in chronic ligamentous laxity and distorted ankle biomechanics); patient age; bone quality; position of the foot at time of injury; and the magnitude, direction, and rate of loading. Specific mechanisms and injuries are discussed in the section on classification.

      Clinical Evaluation

  • Patients may have a variable presentation, ranging from a limp to nonambulatory in significant pain and discomfort, with swelling, tenderness, and variable deformity.

  • Neurovascular status should be carefully documented and compared with the contralateral side.

  • The extent of soft tissue injury should be evaluated, with particular attention to possible open injuries and blistering. The quality of surrounding tissues should also be noted.

  • The entire length of the fibula should be palpated for tenderness because associated fibular fractures may be found proximally as high as the proximal tibiofibular articulation. A “squeeze test” may be performed approximately 5 cm proximal to the intermalleolar axis to assess possible syndesmotic injury

  • A dislocated ankle should be reduced and splinted immediately (before radiographs if clinically evident) to prevent pressure or impaction injuries to the talar dome and to preserve neurovascular integrity.

    Radiographic Evaluation

  • AP, lateral, and mortise views of the ankle should be obtained.

  • AP view

    • Tibiofibula overlap of <10 mm is abnormal and implies syndesmotic injury.

    • Tibiofibula clear space of >5 mm is abnormal and implies syndesmotic injury.

    • Talar tilt: A difference in width of the medial and lateral aspects of the superior joint space of

      >2 mm is abnormal and indicates medial or lateral disruption.

  • Lateral view

    • The dome of the talus should be centered under the tibia and congruous with the tibial plafond.

    • Posterior tibial tuberosity fractures can be identified, as well as direction of fibular injury.

    • Avulsion fractures of the talus by the anterior capsule may be identified.

    • Anterior or posterior translation of the fibula in relation to the tibia in comparison to the opposite uninjured side is indicative of a syndesmotic injury.

  • Mortise view (Fig. 38.5)

    • This is taken with the foot in 15 to 20 degrees of internal rotation to offset the intermalleolar axis.

    • A medial clear space >4 to 5 mm is abnormal and indicates lateral talar shift.

    • Talocrural angle: The angle subtended between the intermalleolar line and a line parallel to the distal tibial articular surface should be between 8 and 15 degrees. The angle should be within 2 to 3 degrees of the uninjured ankle.

    • Tibiofibular overlap <1 cm indicates syndesmotic disruption.

    • Talar shift >1 mm is abnormal.

       

       

       

  • A physician-assisted stress view with the ankle dorsiflexed and the foot stressed in external rotation can be used to identify medial injury with an isolated fibula fracture. A gravity stress view is an alternative with similar sensitivity.

  • Computed tomography (CT) scans help to delineate bony anatomy, especially in patients with plafond injuries.

  • Magnetic resonance imaging (MRI) may be used for assessing occult cartilaginous, ligamentous, or tendinous injuries.

    Classification

    Lauge-Hansen (Rotational Ankle Fractures)

  • Four patterns are recognized, based on “pure” injury sequences, each subdivided into stages of increasing severity (Figs. 38.6 and 38.7).

     

     

     

     

  • This system is based on cadaveric studies.

  • Patterns may not always reflect clinical reality

  • The system takes into account (1) the position of the foot at the time of injury and (2) the direction of the deforming force.

    Supination–Adduction (SA)

  • This accounts for 10% to 20% of malleolar fractures.

  • This is the only type associated with medial displacement of the talus.

    Stage I: Produces either a transverse avulsion-type fracture of the fibula distal to the level of the joint or a rupture of the lateral collateral ligaments

    Stage II: Results in a vertical medial malleolus fracture

    Supination–External Rotation (SER)

  • This accounts for 40% to 75% of malleolar fractures.

    Stage I: Produces disruption of the anterior tibiofibular ligament with or without an associated avulsion fracture at its tibial or fibular attachment

    Stage II: Results in the typical spiral fracture of the distal fibula, which runs from anteroinferior to posterosuperior

    Stage III: Produces either a disruption of the posterior tibiofibular ligament or a fracture of the posterior malleolus

    Stage IV: Produces either a transverse avulsion-type fracture of the medial malleolus or a rupture of the deltoid ligament

    Pronation–Abduction (PA)

  • This accounts for 5% to 20% of malleolar fractures.

    Stage I: Results in either a transverse fracture of the medial malleolus or a rupture of the deltoid ligament

    Stage II: Produces either a rupture of the syndesmotic ligaments or an avulsion fracture at their insertion sites

    Stage III: Produces a transverse or short oblique fracture of the distal fibula at or above the level of the syndesmosis; this results from a bending force that causes medial tension and lateral compression of the fibula, producing lateral comminution or a butterfly fragment

    Pronation–External Rotation (PER)

  • This accounts for 5% to 20% of malleolus fractures.

    Stage I: Produces either a transverse fracture of the medial malleolus or a rupture of the deltoid ligament

    Stage II: Results in disruption of the anterior tibiofibular ligament with or without avulsion fracture at its insertion sites

    Stage III: Results in a spiral fracture of the distal fibula at or above the level of the syndesmosis running from anterosuperior to posteroinferior

    Stage IV: Produces either a rupture of the posterior tibiofibular ligament or an avulsion fracture of the posterolateral tibia

    Danis–Weber

  • This is based on the level of the fibular fracture: the more proximal, the greater the risk of syndesmotic disruption and associated instability. Three types of fractures are described (Fig. 38.8):

    Type A: This involves a fracture of the fibula below the level of the tibial plafond, an avulsion injury that results from supination of the foot and that may be associated with an oblique

    or vertical fracture of the medial malleolus. This is equivalent to the Lauge–Hansen supination–adduction injury.

    Type B: This oblique or spiral fracture of the fibula is caused by external rotation occurring at or near the level of the syndesmosis; 50% have an associated disruption of the anterior syndesmotic ligament, whereas the posterior syndesmotic ligament remains intact and attached to the distal fibular fragment. There may be an associated injury to the medial structures or the posterior malleolus. This is equivalent to the Lauge–Hansen supination–external rotation injury.

    Type C: This involves a fracture of the fibula above the level of the syndesmosis causing disruption of the syndesmosis almost always with associated medial injury. This category includes Maisonneuve-type injuries and corresponds to Lauge–Hansen pronation–external rotation or pronation–abduction stage III injuries.

     

     

     

    Orthopaedic Trauma Association Classification of Ankle Fractures

    See Fracture and Dislocation Classification Compendium at

    http://www.ota.org/compendium/compendium.html.

    Fracture Variants

  • Maisonneuve fracture

    • Originally described as an ankle injury with a fracture of the proximal third of the fibula, this is a pronation–external rotation type injury; it is important to distinguish it from direct trauma to the fibula.

  • Curbstone fracture

    • This avulsion fracture off the posterior tibia is produced by a tripping mechanism.

  • LeFort–Wagstaffe fracture

    • This anterior fibular tubercle avulsion fracture by the anterior tibiofibular ligament is usually associated with Lauge–Hansen SER-type fracture patterns.

  • Tillaux–Chaput fracture

    • This avulsion of anterior tibial margin by the anterior tibiofibular ligament is the tibial counterpart of the LeFort–Wagstaffe fracture.

  • Collicular fractures

    • Anterior colliculus fracture: The deep portion of the deltoid may remain intact.

    • Posterior colliculus fracture: The fragment is usually nondisplaced because of stabilization by the posterior tibial and the flexor digitorum longus tendons; classically, one sees a “supramalleolar spike” very clearly on an external rotation view.

  • Pronation–dorsiflexion fracture

    • This displaced fracture off the anterior articular surface is considered a pilon variant when there is a significant articular fragment.

      Treatment

      The goal of treatment is anatomic restoration of the ankle joint. Fibular length and rotation must be restored.

      Emergency Room

  • Closed reduction should be performed for displaced fractures. Fracture reduction helps to minimize postinjury swelling, reduces pressure on the articular cartilage, lessens the risk of skin breakdown, and minimizes pressure on the neurovascular structures.

  • Dislocated ankles should be reduced before radiographic evaluation if possible.

  • Open wounds and abrasions should be cleansed and dressed in a sterile fashion as dictated by the degree of injury. Fracture blisters should be left intact and dressed with a well-padded sterile dressing.

  • Following fracture reduction, a well-padded posterior splint with a U-shaped component should be placed to provide fracture stability and patient comfort.

  • Postreduction radiographs should be obtained for fracture reassessment. The limb should be aggressively elevated with or without the use of ice.

    Nonoperative

  • Indications for nonoperative treatment include

    • Nondisplaced, stable fracture patterns with an intact syndesmosis

    • Displaced fractures for which stable anatomic reduction of the ankle mortise is achieved

    • An unstable or multiple trauma patient in whom operative treatment is contraindicated because of the condition of the patient or the limb

  • Patients with stable fracture patterns can be placed in a short leg cast or a removable boot or

    stirrup and allowed to bear weight as tolerated.

  • For displaced fractures, if anatomic reduction is achieved with closed manipulation, a bulky dressing and a posterior splint with a U-shaped component may be used for the first few days while swelling subsides. The patient may then be placed in a long leg cast to maintain rotational control for 4 to 6 weeks with serial radiographic evaluation to ensure maintenance of reduction and healing. If adequate healing is demonstrated, the patient can be placed in a short leg cast or fracture brace. Weight bearing is restricted until fracture healing is demonstrated. The majority of unstable patterns are best treated operatively.

    Operative

  • Open reduction and internal fixation (ORIF) is indicated for:

    • Failure to achieve or maintain closed reduction with amenable soft tissues

    • Unstable fractures that may result in talar displacement or widening of the ankle mortise

    • Fractures that require abnormal foot positioning to maintain reduction (e.g., extreme plantar flexion)

    • Open fractures

  • ORIF should be performed once the patient’s general medical condition, swelling about the ankle, and soft tissue status allow. Swelling, blisters, and soft tissue issues usually stabilize within 5 to 10 days after injury with elevation, ice, and compressive dressings. Occasionally, a closed fracture with severe soft tissue injury or massive swelling may require reduction and stabilization with use of external fixation to allow soft tissue management before definitive fixation.

  • Lateral malleolar fractures distal to the syndesmosis may be stabilized using a lag screw or Kirschner wires with tension banding. With fractures at or above the syndesmosis, restoration of fibular length and rotation is essential to obtain an accurate reduction. This is most often accomplished using a combination of lag screws and plate.

  • Management of medial malleolar fractures is controversial. In general, with a deltoid rupture, the talus follows the fibula. Indications for operative fixation of the medial malleolus include concomitant syndesmotic injury, persistent widening of the medial clear space following fibula reduction, inability to obtain adequate fibular reduction, or persistent medial fracture displacement after fibular fixation. Medial malleolar fractures can usually be stabilized with cancellous screws or a figure-of-eight tension band.

  • Indications for fixation of posterior malleolus fractures include involvement of >25% of the

    articular surface, >2-mm displacement, or persistent posterior subluxation of the talus. Posterior malleolar fixation may be an alternative to syndesmotic fixation as the PITFL remains attached to the fragment. Fixation may be achieved by indirect reduction and placement of an anterior to posterior lag screw, or a posteriorly placed plate and/or screws through a separate incision.

  • Fibula fractures above the plafond may require syndesmotic stabilization. After fixation of the medial and lateral malleoli is achieved, the syndesmosis should be stressed intraoperatively by lateral pull on the fibula with a bone hook or by stressing the ankle in external rotation. Syndesmotic instability can then be recognized clinically and under image intensification. Distal tibia–fibula joint reduction is held with a large pointed reduction clamp. A syndesmotic screw is placed 1.5 to 2.0 cm above the plafond from the fibula to the tibia. Controversy exists as to the number of purchased cortices (three or four) and the size of the screw (3.5 or 4.5 mm). The need for ankle dorsiflexion during syndesmotic screw placement is also controversial. An anatomically reduced syndesmosis cannot be overtightened. Fixation of a posterior malleolar fracture fragment may obviate the need for syndesmotic fixation.

  • Very proximal fibula fractures with syndesmosis disruption can usually be treated with syndesmosis fixation without direct fibula reduction and stabilization. One must, however, ascertain correct fibula length and rotation before placing syndesmotic fixation.

  • Following fracture fixation, the limb is placed in a bulky dressing incorporating a plaster splint. Progression to weight bearing is based on the fracture pattern, stability of fixation, patient compliance, and philosophy of the surgeon.

    Open Fractures

  • These fractures require urgent irrigation and debridement in the operating room. Usually a transverse medial wound is required.

  • External fixation may be used to temporize patients until soft tissue conditions allow for definitive fixation.

  • Stable fixation is important prophylaxis against infection and helps soft tissue healing. It is permissible to leave plates and screws exposed, but efforts should be made to cover hardware, if possible

  • Tourniquet use is usually unnecessary in the cases and leads to postsurgical swelling and reperfusion injury.

  • Antibiotic prophylaxis should be continued postoperatively for 24 hours.

  • Serial debridements may be required for removal of necrotic, infected, or compromised tissues.

    Complications

  • Nonunion: Nonunions about the ankle are rare. Most commonly affecting the medial malleolus. These are associated with closed treatment, residual fracture displacement, interposed soft tissue, or associated lateral instability resulting in shear stresses across the deltoid ligament. If symptomatic, it may be treated with ORIF or electrical stimulation. Excision of the fragment may be necessary if it is not amenable to internal fixation and the patient is symptomatic.

  • Malunion: The lateral malleolus is usually shortened and malrotated; a widened medial clear space and a large posterior malleolar fragment are most predictive of poor outcome. The medial malleolus may heal in an elongated position resulting in residual instability.

  • Wound problems: Skin edge necrosis (3%) may occur; there is decreased risk with minimal swelling, no tourniquet, and good soft tissue technique. Fractures that are operated on in the presence of fracture blisters or abrasions have more than twice the complication rate.

  • Infection: Occurs in >2% of closed fractures; leave implants in situ if stable, even with deep infection. One can remove the implant after the fracture unites. The patient may require serial debridements with possible arthrodesis as a salvage procedure.

  • Posttraumatic arthritis: This is secondary to damage at the time of injury, from altered mechanics, or as a result of inadequate reduction. It is rare in anatomically reduced fractures, with increasing incidence with articular incongruity.

  • Reflex sympathetic dystrophy: This is rare and may be minimized by anatomic restoration of the ankle and early return to function.

  • Compartment syndrome of the leg or foot: This is rare.

  • Tibiofibular synostosis: This is associated with the use of a syndesmotic screw and is usually asymptomatic.

  • Loss of reduction: This is reported in 25% of unstable ankle injuries treated nonoperatively (Fig. 38.9).

     

     

     

  • Loss of ankle ROM may occur.

    Plafond (Pilon) Fractures

    Epidemiology

  • Pilon fractures account for 7% to 10% of all tibia fractures.

  • Most pilon fractures are a result of high-energy mechanisms; thus, concomitant injuries are common and should be ruled out.

  • These are most common in men 30 to 40 years old.

    Mechanism of Injury

  • Axial compression (High energy): Fall from a height, MVC

    • The force is axially directed through the talus into the tibial plafond, causing impaction of the articular surface; it may be associated with significant comminution. If the fibula remains intact, the ankle is forced into varus with impaction of the medial plafond. Plantar flexion or dorsiflexion of the ankle at the time of injury results in primarily posterior or anterior plafond

      injury, respectively.

  • Rotational (Low energy): Sporting accident

    • Mechanism is primarily torsion combined with a varus or valgus stress. It produces two or more large fragments and minimal articular comminution. There is usually an associated fibula fracture, which is usually transverse or short oblique.

  • Combined compression and shear

    • These fracture patterns demonstrate components of both compression and shear. The vector of these two forces determines the fracture pattern.

  • Because of their high-energy nature, these fractures can be expected to have specific associated

    injuries: Calcaneus, tibial plateau, pelvis, and vertebral fractures.

    Clinical Evaluation

  • Most pilon fractures are associated with high-energy trauma; full trauma evaluation and secondary survey is usually necessary.

  • Patients typically present nonambulatory with variable gross deformity of the involved distal leg.

  • Evaluation includes assessment of neurovascular status and evaluation of any associated injuries.

  • The tibia is nearly subcutaneous in this region; therefore, fracture displacement or excess skin pressure may convert a closed injury into an open one.

  • Swelling is often massive and rapid, necessitating serial neurovascular examinations as well as assessment of skin integrity, necrosis, and fracture blisters.

  • Meticulous assessment of soft tissue damage is of paramount importance. Significant damage occurs to the thin soft tissue envelope surrounding the distal tibia as the forces of impact are dissipated. This may result in inadequate healing of surgical incisions with wound necrosis and skin slough if not treated appropriately. Some advise waiting 7 to 10 days for soft tissue healing to occur before planning surgery.

    Radiographic Evaluation

  • AP, lateral, and mortise radiographs should be obtained.

  • CT with coronal and sagittal reconstruction is helpful to evaluate the fracture pattern and articular surface.

  • Careful preoperative planning is essential with a strategically planned sequence of reconstruction; radiographs of the contralateral side may be useful as a template for preoperative planning.

    Classification

    Rüedi and Allgöwer

  • This is based on the severity of comminution and the displacement of the articular surface (Fig. 38.10).

     

     

     

  • It has been the most commonly used classification. Its relevance today is minimal.

  • Prognosis correlates with increasing grade.

    Type I: Nondisplaced cleavage fracture of the ankle joint

    Type II: Displaced fracture with minimal impaction or comminution

    Type III: Displaced fracture with significant articular comminution and metaphyseal impaction

    Orthopaedic Trauma Association Classification of Distal Tibia Fractures

    See Fracture and Dislocation Classification Compendium at http://www.ota.org/compendium/compendium.html.

    Treatment

    This is based on many factors, including patient age and functional status; severity of injury to bone, cartilage, and soft tissue envelope; degree of comminution and osteoporosis; and the capabilities of the surgeon.

    Nonoperative

    Treatment involves a long leg cast for 6 weeks followed by fracture brace and ROM exercises or early ROM exercises.

  • This is used primarily for nondisplaced fracture patterns or severely debilitated patients.

  • Manipulation of displaced fractures is unlikely to result in reduction of intra-articular fragments.

  • Loss of reduction is common.

  • Inability to monitor soft tissue status and swelling is a major disadvantage.

    Operative

  • Displaced pilon fractures are usually treated surgically.

    Timing of Surgery

  • Surgery may be delayed for several days (7 to 21 days on average) to allow for optimization of soft tissue status, including a diminution of swelling about the ankle, resolution of fracture blisters, and sloughing of compromised soft tissues.

  • High-energy injuries can be treated with spanning external fixation to provide skeletal stabilization, restoration of length and partial fracture reduction while awaiting definitive surgery. Associated fibula fractures may undergo ORIF at the time of fixator application.

    Goals. The goals of operative fixation of pilon fractures include:

  • Maintenance of fibula length and stability

  • Restoration of tibial articular surface

  • Bone grafting of metaphyseal defects

  • Stabilizing of the distal tibia

    Surgical Tactic

  • Articular fracture reduction can be achieved percutaneously or through small limited approaches assisted by a variety of reduction forceps, with fluoroscopy to judge fracture reduction.

  • The metaphyseal fracture can be stabilized either with plates or with a nonspanning or spanning external fixator.

  • Grafting of metaphyseal defects with some type of osteoconductive material is indicated.

  • Internal fixation: Open fracture reduction and plate fixation may be the best way to achieve a precisely reduced articular surface. To minimize the complications of plating, the following techniques have been recommended:

    • Surgical delay until definitive surgical treatment using initial spanning external fixation for high-energy injuries

    • Use of small, precontoured, low-profile implants and mini-fragment screws

    • Avoidance of incisions over the anteromedial tibia

    • Use of indirect reduction techniques to minimize soft tissue stripping

    • Use of percutaneous techniques for plate insertion

  • Joint spanning external fixation: This may be used in patients with significant soft tissue compromise or open fractures. Reduction is maintained via distraction and ligamentotaxis. If adequate reduction is obtained, external fixation may be used as definitive treatment.

    • Articulating versus nonarticulating spanning external fixation: Nonarticulating (rigid) external fixation are most commonly used, theoretically allowing no ankle motion. Articulating external fixation allows motion in the sagittal plane, thus preventing ankle varus and shortening;

      application is limited, but theoretically it results in improved chondral lubrication and nutrition owing to ankle motion, and it may be used when soft tissue integrity is the primary indication for external fixation.

  • Hybrid external fixation: This is a type of nonspanning external fixator. Fracture reduction is enhanced using thin wires with or without olives to restore the articular surface and maintain bony stability. It is especially useful when internal fixation of any kind is contraindicated. There is a reported 3% incidence of deep wound infection.

    Arthrodesis. Few advocate performing this procedure acutely. It is best done after fracture comminution has consolidated and soft tissues have recovered. It is generally performed as a salvage procedure after other treatments have failed and posttraumatic arthritis has ensued.

    Postoperative Management

  • Initial splint placement in neutral dorsiflexion with careful monitoring of soft tissues

  • Early ankle and foot motion when wounds and fixation allow

  • Non–weight bearing for 10 to 16 weeks, then progression to full weight bearing once there is radiographic evidence of healing

    Complications

  • Even when accurate reduction is obtained, predictably excellent outcomes are not always achieved, and less than anatomic reduction can lead to satisfactory outcomes.

  • Soft tissue slough, necrosis, and hematoma: These result from initial trauma combined with improper handling of soft tissues. One must avoid excessive stripping and skin closure under tension. Secondary closure, skin grafts, or muscle flaps may be required for adequate closure. These complications have been minimized since recognition of the initial soft tissue insult and the strategies to minimize the effects (spanning external fixation, minimally invasive surgery, etc.)

  • Nonunion: Results from significant comminution and bone loss, as well as hypovascularity and infection. It has a reported incidence of 5% regardless of treatment method.

  • Malunion: Common with nonanatomic reduction, inadequate buttressing (early fixator removal) followed by collapse, or premature weight bearing. The reported incidence is up to 25% with use of external fixation.

  • Infection: Associated with open injuries and soft tissue devitalization. It has a high incidence with early surgery under unfavorable soft tissue conditions. Late infectious complications may manifest as osteomyelitis, malunion, or nonunion.

  • Posttraumatic arthritis: More frequent with increasing severity of intra-articular comminution, it emphasizes the need for anatomic restoration of the articular surface.

  • Tibial shortening: This is caused by fracture comminution, metaphyseal impaction, or initial failure to restore length by fibula fixation.

  • Decreased ankle ROM: Patients usually average <10 degrees of dorsiflexion and <30 degrees of plantar flexion.

    Lateral Ankle Ligament Injuries

  • Sprains of the lateral ligaments of the ankle are the most common musculoskeletal injury in sports.

  • In the United States, it is estimated that one ankle inversion injury occurs each day per 10,000 people.

  • One year after injury, occasional intermittent pain is present in up to 40% of patients.

    Mechanism of Injury

  • Most ankle sprains are caused by a twisting or turning event to the ankle. This can result from either internal or external rotation.

  • Mechanism of injury and the exact ligaments injured depend on the position of the foot and the direction of the stress.

    • With ankle plantar flexion, inversion injuries first strain the anterior talofibular ligament and then the calcaneofibular ligament.

    • With the ankle dorsiflexion and inversion, the injury is usually isolated to the calcaneofibular

      ligament. With ankle dorsiflexion and external rotation, the injury more likely will involve the syndesmotic ligaments. The syndesmotic ligaments, and in particular the posterior and inferior tibiofibular ligament, can also be injured with the ankle dorsiflexed and the foot internally rotated.

      Classification

  • Mild ankle sprain: Patients have minimal functional loss, no limp, minimal or no swelling, point tenderness, and pain with reproduction of mechanism of injury.

  • Moderate sprain: Patients have moderate functional loss, inability to hop or toe rise on the injured ankle, a limp with walking, and localized swelling with point tenderness.

  • Severe sprain: This is indicated by diffuse tenderness, swelling, and a preference for non–weight bearing.

  • This system does not delineate the specific ligaments involved.

    Clinical Evaluation

  • Patients often describe a popping or tearing sensation in the ankle, and they remember the immediate onset of pain.

  • Some patients have an acute onset of swelling around the lateral ankle ligaments and difficulty with weight bearing secondary to pain.

  • Significant physical examination findings may include swelling, ecchymosis, tenderness, instability, crepitus, sensory changes, vascular status, muscle dysfunction, and deformity.

  • The location of the pain helps to delineate the involved ligaments, and it can include the lateral aspect of the ankle, the anterior aspect of the fibula, the medial aspect of the ankle, and the syndesmotic region.

  • The value of stress testing of the lateral collateral ankle ligaments in the acute setting is controversial.

    • At the time of injury, before swelling and inflammation occur, the physician may be able to obtain valuable information by performing an anterior drawer and varus stress examination of the lateral collateral ankle ligaments.

    • In patients who present several hours after injury and who have powerful reflex inhibition, a stress test without anesthesia is unlikely to give valuable clinical information.

  • Injury to the lateral collateral ankle ligaments should be differentiated from other periarticular

    ligamentous injuries on examination. Significant initial ecchymosis along the heel indicates possible subtalar ligamentous sprain. To evaluate potential syndesmotic injury, the squeeze test and external rotation stress tests are performed (see “Clinical Evaluation” section, p. 491).

    Radiographic Evaluation

  • Most patients should probably undergo radiographic examination to rule out occult foot and ankle injuries with an x-ray series of the foot and ankle.

    • The injuries that need to be ruled out include fracture of the base of the fifth metatarsal, navicular fracture, fracture of the anterior process of the calcaneus, fracture of the lateral process of the talus, os trigonal fracture, talar dome fracture (osteochondritis dissecans), and posterior malleolar fracture.

  • In the acute setting, there probably is little role for performing radiographic stress testing.

    Treatment

  • Nonsurgical approaches are preferred for initial treatment for acute ankle sprains.

  • Initial treatment involves the use of rest, ice, compression (elastic wrap), elevation (RICE) and protected weight bearing.

    • For mild sprains, one can start early mobilization, ROM, and isometric exercises.

    • For moderate or severe sprains, one can immobilize the ankle in neutral position, or slight dorsiflexion, for the first 10 to 14 days, and then initiate mobilization, ROM, and isometric exercises. Crutches are discontinued once the patient can tolerate full weight on the ankle.

  • Once the initial inflammatory phase has resolved, for the less severe ankle sprains (mild to moderate), one can initiate a home rehabilitation program consisting of eversion muscle group strengthening, proprioceptive retraining, and protective bracing while the patient gradually returns to sports and functional activities. Bracing or taping is usually discontinued 3 to 4 weeks after resuming sports. For more severe sprains, taping or bracing programs are continued during sports activities for 6 months, and a supervised rehabilitation program used.

  • Patients who continue to have pain in the ankle that does not decrease with time should be reevaluated for an occult osseous or chondral injury.

  • Patients with a history of recurrent ankle sprains who sustain an acute ankle sprain are treated in a manner similar to that described earlier.

    Syndesmosis Sprains

  • Syndesmotic sprains account for approximately 1% of all ankle sprains.

  • Syndesmotic sprains may occur without a fracture or frank diastasis.

  • Many of these injuries probably go undiagnosed and cause chronic ankle pain.

  • Injuries to the syndesmotic ligaments are more likely to result in greater impairment than straightforward lateral ankle sprains. In athletes, syndesmotic sprains result in substantially greater lost time from sports activities.

Classification

Diastases of the distal tibiofibular syndesmosis were classified into four types by Edwards and DeLee.

  1. Type I diastasis involves lateral subluxation without fracture.

  2. Type II involved lateral subluxation with plastic deformation of the fibula.

  3. Type III involves posterior subluxation/dislocation of the fibula.

  4. Type IV involves superior subluxation/dislocation of the talus within the mortise.

    Clinical Evaluation

    • Immediately after a syndesmotic ankle sprain, the patient will have well-localized tenderness in the area of the sprain, but soon thereafter, with ensuing swelling and ecchymosis, the precise location of the sprain often becomes obscured.

    • Patients ordinarily present to physicians several hours, if not days, after these injuries, with difficulty in weight bearing, ecchymosis extending up the leg, and marked swelling. The clue to chronic, subclinical syndesmotic sprains is the history of vague ankle pain with push-off and normal imaging studies.

    • The clinical examination involves palpating the involved ligaments and bones. The fibula should be palpated in a proximal to distal direction. The proximal tibiofibular joint should be assessed for tenderness or associated injury.

    • Two clinical tests can be used to isolate syndesmotic ligament injury.

    • The squeeze test: This involves squeezing the fibula at the mid calf. If this maneuver reproduces distal tibiofibular pain, it is likely that the patient has sustained some injury to the syndesmotic region.

    • The external rotation stress test: The patient is seated, with the knee flexed at 90 degrees. The examiner stabilizes the patient’s leg and externally rotates the foot. If this reproduces pain at the syndesmosis, the test is positive, and the physician should assume, in the absence of bony injuries, that a syndesmotic injury has occurred.

      Radiographic Evaluation

    • The radiographic evaluation of a syndesmotic injury, in an acute setting, involves an attempt at weight-bearing radiographs of the ankle (AP, mortise, lateral) and, if negative, an external rotation stress view.

    • Without injury, a weight-bearing mortise view should show:

      • No widening of the medial clear space between the medial malleolus and the medial border of

        the talus

      • A tibiofibular clear space (the interval between the medial border of the fibula and the lateral border of the posterior tibial malleolus) of 6 mm or less

    • With acute sprains, on lateral radiographs, a small avulsion fragment may be apparent. Similarly,

      with more chronic problems, calcification of the syndesmosis or posterior tibia may suggest syndesmotic injury.

    • When routine x-rays are negative, and the patient is still suspected of having a syndesmotic injury, stress radiographs can be considered. The examiner should inspect stress radiographs for widening of the medial joint space and tibiofibular clear space on the mortise view and for posterior displacement of the fibula relative to the tibia on the lateral view.

    • In difficult-to-diagnose acute cases or latent presentations, an MRI evaluation of the syndesmosis may delineate injury to the syndesmotic ligaments.

      Treatment

    • Tibiofibular syndesmotic ligamentous injuries are slower to recover than other ankle ligamentous injuries and may benefit from a more restrictive approach to initial management.

    • Patients are immobilized in a non–weight-bearing cast for 2 to 3 weeks after injury. This is followed by use of a protective, modified, articulated ankle–foot orthosis that eliminates external rotation stress on the ankle for a variable period, depending on the functional needs and sports activities of the patient.

    • Operative treatment is considered for patients with irreducible diastasis. To hold the syndesmotic ligaments while healing, two screws are usually placed at the superior margin of the syndesmosis in a nonlagged fashion, from the fibula into the tibia. The patients are maintained non–weight bearing for 6 weeks, and the screws are removed approximately 12 to 16 weeks after fixation.

      Achi les Tendon Rupture

      Epidemiology

    • Most Achilles tendon problems are related to overuse injuries and are multifactorial.

    • The principal factors include host susceptibility and mechanical overload.

    • The spectrum of injury ranges from paratenonitis to tendinosis to acute rupture.

    • In a trauma setting, a true rupture is the most common presentation.

    • Delayed or missed diagnosis of Achilles tendon rupture by primary treating physicians is relatively common (up to 25%).

      Anatomy

    • The Achilles tendon is the largest tendon in the body.

    • It lacks a true synovial sheath and instead has a paratenon with visceral and parietal layers permitting approximately 1.5 cm of tendon glide.

    • It receives its blood supply from three sources:

      1. The musculotendinous junction

      2. The osseous insertion

      3. Multiple mesosternal vessels on the anterior surface of the tendon

      Clinical Evaluation

    • With either partial or complete Achilles tendon rupture, patients typically experience sharp pain, often described as feeling like being kicked in the leg.

    • With a partial rupture, physical examination may only reveal a localized tender area of swelling.

    • With complete rupture, examination normally reveals a palpable defect in the tendon.

    • Goals are to restore normal musculotendinous length and tension and thereby to optimize ultimate strength and function of the gastrocnemius–soleus complex.

    • Whether operative or nonoperative treatment best achieves these goals remains a matter of controversy.

      • Proponents of surgical repair point to lower recurrent rupture rates, improved strength, and a higher percentage of patients who return to sports activities.

      • Proponents of nonoperative treatment stress the high surgical complication rates resulting from

        wound infection, skin necrosis, and nerve injuries.

      • When major complications, including recurrent ruptures, are compared, both forms of treatment have similar complication rates.

      • Most authors tend to treat active patients who are interested in continuing athletic endeavors

        with operative treatment and inactive patients or those with other complicating medical factors

        (e.g., immunosuppression, soft tissue injuries, history of recurrent lower extremity infections, vascular or neurologic impairment) with nonoperative approaches.

    • Nonoperative treatment begins with a period of immobilization.

      • Initially, the leg is placed in a splint for 2 weeks, with the foot in plantar flexion to allow hematoma consolidation.

      • Thereafter, a short or long leg cast is placed for 6 to 8 weeks, with less plantar flexion and

        progressive weight bearing generally permitted at 2 to 4 weeks after injury.

      • After removal of the cast, a heel lift is used while making the transition back to wearing normal shoes.

      • Progressive resistance exercises for the calf muscles are started at 8 to 10 weeks, with a return

        to athletic activities at 4 to 6 months.

      • Patients are informed that attainment of maximal plantar flexion power may take 12 months or more and that some residual weakness is common.

    • Surgical treatment is often preferred when treating younger and more athletic patients.

      • Several different operative techniques have been described, including percutaneous and open approaches.

      • Percutaneous approaches have the advantage of decreased dissection but have historically

        carried the disadvantages of potential entrapment of the sural nerve and an increased chance of inadequate tendon capture.

      • Open approaches have the intrinsic advantages of permitting complete evaluation of the injury and inspection of final tendon end reapproximation; however, they carry the disadvantages of higher rates of wound dehiscence and skin adhesion problems.

        • The surgical technique uses a medial longitudinal approach to avoid injury to the sural nerve.

        • The paratenon is carefully dissected, and sutures are placed in each tendon end for tendon reapproximation. The paratenon is closed in a separate layer.

      • Postoperative management consists of a partial weight bearing or weight bearing as tolerated in

        a short leg cast or boot for 6 to 8 weeks. As with nonoperatively treated patients, progressive resistance exercises are started at 8 to 10 weeks, with a return to sports at 4 to 6 months. Newer techniques and stronger sutures have led to more accelerated rehab protocols.

      • With distal ruptures or sleeve avulsions, an open technique and reattachment of the tendon to the calcaneus is performed. This is usually done with transosseous suture fixation.

        Peroneal Tendon Subluxation

    • Subluxation and dislocation of the peroneal tendons are uncommon and usually result from sports activities.

    • They normally result from forced dorsiflexion or inversion and have been described principally in skiers when they dig the tips of the skis into the snow and create a sudden deceleration force with dorsiflexion of the ankle within the ski boot.

    • The injury is easily misdiagnosed as an ankle sprain, and it can result in recurrent or chronic

      dislocation.

    • Presentation is similar to that of a lateral ankle sprain with lateral ankle swelling, tenderness, and ecchymosis.

      Peroneal Tendon Subluxation

    • Patients with peroneal tendon subluxation or dislocation demonstrate tenderness posterior to the lateral malleolus.

    • The anterior drawer test is negative, and the patient has discomfort and apprehension with resisted eversion of the foot.

    • Radiographic evaluation of a patient with peroneal tendon subluxation or dislocation may reveal a small fleck of bone off the posterior aspect of the lateral malleolus, which is best seen on the internal oblique or mortise view.

    • If the diagnosis is unclear, as a result of swelling and diffuse ecchymosis, an MRI evaluation may help to delineate this soft tissue injury.

      Treatment

    • When the initial reduction of dislocated tendons is stable, nonoperative techniques can be successful.

      • Management consists of immobilization in a well-molded cast with the foot in slight plantar flexion and mild inversion in an attempt to relax the superior peroneal retinaculum and to maintain reduction in the retrofibular space. Non–weight-bearing immobilization is continued for 6 weeks to allow adequate time for retinacular and periosteal healing.

    • When the diagnosis is made on a delayed basis or the patient presents with recurrent dislocations, operative treatment is considered because nonoperative measures are unlikely to work.

      • Surgical alternatives include transfer of the lateral Achilles tendon sheath, fibular osteotomy to create a deeper groove for the tendons, rerouting of the peroneal tendons under the fibulocalcaneal ligament, or simple reconstructive repair of the superior peroneal retinaculum with relocation of the tendons.

      • Postoperatively, the leg is splinted for 1 to 2 weeks in a slightly inverted and plantar flexed position; patients are then started on a passive motion exercise program to reduce scar formation in the peroneal groove and to increase the likelihood of good tendon nutrition and retinacular healing. Weight bearing is initiated 6 weeks postoperatively, and rehabilitation and focusing of strength and ROM are initiated soon thereafter.