Diagnosis and Treatment of Ankle Fractures

CE ...... DIRECTED READING

Diagnosis and Treatment Of Ankle Fractures

ANNE M SCOTT, BSRS, R.T.(R)

Ankle fractures are common After reading this article, readers should be able to: among all populations, ■ Review ankle joint anatomy and the role of ligament structures in providing stability. ■ although incidence increases Describe the role of imaging in patient diagnosis, treatment planning and follow-up. ■ in the elderly. They are most Discuss classification systems for ankle injury patterns. ■ often the result of simple falls Determine when surgical reduction and internal fixation of ankle fractures is required and complications that may result from surgery. and athletic injuries but also ■ may be caused by underlying Describe rehabilitation techniques and functional recovery prognosis. pathology. A thorough patient evaluation with description of njuries to the ankle are common used to evaluate these injuries may the mechanism of injury is key in the general population and in include conventional radiography, mag- to proper diagnosis. 1,2 athletes. It is estimated that netic resonance (MR) imaging, comput- 260 000 Americans sustain an ed tomography (CT), radionuclide bone This article examines the ankle fracture each year and scanning and ultrasonography. use of radiography and I that ankle fractures occur in about 100 Stable fractures are effectively treat- other imaging modalities in per 100 000 people in major cities.3,4 ed with casts and removable braces.9 diagnosing ankle injuries, as They constitute 21% of all sports-relat- Unstable fractures must be reduced well as several classification ed injuries.1 One study reported that promptly and accurately to optimize systems available to describe the incidence of ankle fractures has healing and minimize the length of the pattern of injury and increased in recent decades, especially hospital stay.4 When surgery is required, aid in treatment planning. among the elderly.5 a wide variety of fixation devices and Treatment, rehabilitation tech- Ankle fractures often are compli- surgical techniques are used for open niques and possible complica- cated by associated ligamentous injuries reduction and internal fixation of the tions of ankle fractures also that must be repaired to ensure joint ankle.6 Following surgery, these frac- are discussed. stability.6 The most common cause of tures also are treated with a period of ankle injury is excessive inversion stress.7 immobilization, then rehabilitation This article is a Directed Fractures also may result from abnormal to attempt functional recovery of the Reading. Your access to stress applied to the joint or when the joint.2,10 Patient age, severity of injury, Directed Reading quizzes for strength of the bones is insufficient to quality of treatment and use of reha- continuing education credit support normal stress.8 Two classifica- bilitation interventions are parameters is determined by your area of tion systems, the Lauge-Hansen and the used to predict the outcome of ankle interest. For access to other Danis-Weber, or Weber, are used widely fractures.2,5 quizzes, go to www.asrt.org to aid in the diagnosis and treatment of /store. ankle fractures resulting from an acute Epidemiology injury. Several other fracture types do Ankle fractures are common to all not fit into these classification schemes, groups of the population. Most ankle including stress fractures and pathologic fractures are inversion injuries caused by fractures. Diagnostic imaging techniques sports activities or simple falls.11 Several

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studies have shown that the incidence of ankle fractures has continued to rise, especially in postmenopausal women. The peak age range for men to suffer ankle fractures is 15 to 24 years, whereas the peak age range for women is 65 to 75 years.11 The injuries also occur frequently in the pediatric population. According to Davis, fractures of the ankle make up 5% of all pediatric fractures and 15% of physeal injuries with a peak incidence between 8 and 15 years.12 Sports that reportedly lead to unstable ankle fractures include football, baseball, cheerleading, soft- ball, wrestling, basketball, gymnastics, moto- cross, rock climbing, rodeo, rugby, soccer and volleyball.1,13 Risk factors for ankle fracture include obesity, diabetes, osteoporosis, prior injury and the level and type of physical activity.14-16 Falls are more common in the elderly, but one study reported that a higher rate of falls did not correlate with an increased rate of ankle fractures.17 Obesity is a risk factor for Figure 1. Posterior aspect of right ankle joint depicting bony and ligamentous ankle fractures in children and adults and anatomy. also is a predictor of poorer outcome following ankle fractures in adults.15 Type 2 diabetes has been associated with increased rates of foot and fibula are long bones, whereas the talus is short and ankle fractures and corresponds to a higher fracture squarish in shape. Long bones have a shaft called the severity.3,14 Osteoporosis also is a risk factor for ankle diaphysis, which is located between 2 larger ends called fracture and subsequent refracture. Known risk factors the epiphyses. The metaphysis connects the diaphysis for osteoporosis include female gender, older age, lower and epiphyses. The diaphysis is made up of compact body mass index and a family history of the disease.14 bone that surrounds a medullary cavity containing The risk of refracture also is significant for elderly marrow. The epiphysis consists of spongy bone covered patients. Center et al found that refracture risk of low- by compact bone. Hyaline cartilage covers the end of trauma ankle fracture in men and women was equal each epiphysis.20 to the initial fracture risk of a man 20 years older or Longitudinal growth occurs between the epiphy- a woman 10 years older. For example, a women who sis and the metaphysis at the epiphyseal cartilage is aged 60 to 69 years has the same refracture risk as (growth plate). The growth is stimulated by growth a woman aged 70 to 79 years has of initial fracture.16 and sex hormones. The plate ossifies and becomes Refractures reported in this study were most likely to the epiphyseal line when longitudinal growth ceases. occur in the first 2 years following the first fracture. The density and thickness of bone may change at any The authors reported that incidental low-trauma frac- time because of hormonal influence, such as growth tures are a sign that subsequent osteoporotic fractures hormone, parathyroid hormone or cortisol. Changes are likely and that these patients should receive preven- in osteoblastic (bone producing) and osteoclastic tive therapy.16 (bone resorbing) activity also affect bone density (the amount of calcium and other minerals present in the Ankle Anatomy and Biomechanics bone).20 Accessory ossification centers may be mistak- The ankle comprises 3 bones: the distal tibia, distal en for fractures in the developing ankle and foot of a fibula and talus. It also includes the joint capsule and pediatric patient. The most common is located poste- supporting ligaments (see Figure 1).1,18,19 The tibia and rior to the talus and is called the os trigonum. Usually

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ossification centers appear to have a regular shape Laterally, 3 major ligaments resist inversion, anterior and have a well-defined cortex on radiographs.19 displacement of the talus and internal rotation. They are the anterior talofibular ligament, the calcaneofibular Joint Mechanics ligament and the posterior talofibular ligament. The Two separate articulations allow movement at the anterior talofibular ligament resists inversion when the ankle. The true ankle joint, also known as the talocrural ankle is in plantar flexion and the calcaneofibular liga- joint or mortise joint, consists of articulations between ment resists inversion when the ankle is in dorsiflexion.1 the lateral malleolus of the fibula, the inferior surface Computer models used to design ankle prostheses and medial malleolus of the tibia and the talus.1,18,19 The demonstrated that during dorsiflexion, some fibers mortise is formed by the inner and distal articular sur- within the calcaneofibular and tibiocalcaneal liga- faces of the tibia and the fibula, which serve as a roof ments rotate isometrically around their origins and over the talus, creating a uniplanar hinge joint.21 The insertions while all other more anterior ligament fibers medial and lateral malleoli allow controlled plantar slacken. During plantar flexion, however, the more pos- flexion (as when pointing the toes down and lifting terior ligament fibers slacken. In addition, the point of heels off the floor) and dorsiflexion (as when pulling articular contact moves from the posterior part of the the toes up from the floor).19,21 The talus is slightly wider mortise in plantar flexion to the anterior part in dor- anteriorly, making the ankle more stable when in dorsiflexion. This causes the talus to roll forward during siflexion because the talus is effectively locked between dorsiflexion and backward during plantar flexion.22 the malleoli.1,19 The posterior malleolus, located on the There are 2 fat pads around the ankle that are posterior aspect of the tibia, may be fractured in asso- useful for detecting joint effusion and injury on radio- ciation with other ankle fractures or ligament injuries. graphs: the anterior (or normal) pretalar fat pad Posterior malleolus fractures often are associated with and the posterior pericapsular fat pad.23 Beneath the fibula fractures and are considered to be unstable.7 The anterior pretalar fat pad is a fibrous, synovium-lined talus and calcaneus are connected to the malleoli by the capsule that is attached to the tibia, fibula and talus. lateral and medial collateral ligament complexes.19 When injured, it secretes synovial fluid that distends The tibiofibular syndesmosis joint allows slight wid- the fibrous capsule and causes displacement of the fat ening between the tibia and fibula. The syndesmotic pad. Similarly, the posterior fat pad, located within ligament is located between the tibia and fibula at the space between the posterior tibia and talar bones, the level of the tibial plafond (ceiling). This ligament is displaced when a joint is injured, but requires more allows 1-2 mm of widening at the mortise during plan- fluid build-up in the fibrous capsule that displaces the tar flexion and dorsiflexion.21 The posterior and ante- fat pad to be noticeable.23 rior tibiofibular ligaments strengthen this joint.19 The gliding movements of the intertarsal joints allow Fracture Patterns other slight movements of the ankle joint.18 The subtalar When a fracture occurs, the rigid structure and joint often is included in ankle injury evaluation because continuity of the bone or bones involved also breaks.20 it is where inversion (facing the sole of the foot inward) The ring principle may be used to describe the injury and eversion (facing the sole of the foot outward) occur. pattern of the ankle joint and its supporting ligaments. The joint comprises the talus and the calcaneus.7 This means that when a fracture or ligament rupture The distal tibia absorbs the compressive loads and occurs on 1 side of the joint or “ring,” another fracture stress placed on the ankle.21 Joint motion is guided or rupture is likely to be present elsewhere.19 Blood ves- and stabilized through a close interaction between the sels within the bone are damaged as well as surround- geometry of the ligaments and the shapes of the articu- ing soft tissues. The fractured bone undergoes 5 stages lar surfaces.22 Ankle stability is largely the role of the of healing: hematoma formation, granulation tissue ligament structures. The deltoid ligament stabilizes the formation, callus formation, bony callus formation medial side of the ankle and has superficial and deep (ossification) and remodeling. components.1 The superficial component consists of After ankle fracture, a hematoma first forms the tibiotalar, tibionavicular and tibiocalcanean liga- between the ends of the bone fragments and an ments. The deep component is the primary medial sta- inflammatory response develops. The hematoma serves bilizer of the ankle. Eversion or external rotation of the as the basis for a fibrin network to support and pro- ankle may damage this ligament.1 mote granulation tissue growth. New capillaries extend

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into the granulation tissue and phagocytic cells, which Ankle Rules to determine whether radiographs are remove debris. During the granulation tissue forma- needed. The rules state that the patient must meet 1 of tion stage, fibroblasts, which lay down new collagen 3 criteria for radiographs to be deemed appropriate. fibers, move to the site. Chondroblasts start to form The criteria include25: cartilage as well. The bone fragments then are held ■ Inability to bear weight immediately after the together by this delicate procallus or fibrocartilaginous injury. callus during the callus formation stage. Osteoblasts ■ Point tenderness over the medial malleolus, on then begin to generate new bone to fill in the gap and the talus or calcaneus, or the posterior edge or osteogenic activity eventually transforms the fibrocar- inferior tip of the lateral malleolus. tilaginous callus into bony callus. The repaired bone ■ Inability to walk 4 steps in the emergency then is remodeled in the final stage by osteoblastic and department. osteoclastic activity in response to mechanical stresses Other imaging modalities may be used when the on the bone. Over time, mature compact bone replaces results of conventional radiography are inconclusive or the excess callus.20 in cases of multiple trauma.1

Medical History and Evaluation Diagnostic Imaging During initial evaluation of a patient suffering from Conventional radiography is considered the most an ankle injury, the clinician should obtain a detailed appropriate initial and low-cost examination for sus- medical history that includes the mechanism of injury. pected ankle fractures and associated syndesmosis Ankle fractures may be mistaken for sprains.1 Some injuries.6,8 Other more sensitive and more expensive fractures, including the “snowboarder’s fracture” are imaging exams may be used to better identify ankle difficult to distinguish on physical examination from injuries or for treatment planning. These include CT, a lateral ankle sprain.17 Ankle-inversion trauma may MR, ultrasonography and radionuclide bone scan- result in physeal injuries in children, which may lead to ning. Imaging techniques also are used during surgery joint deformity if not properly diagnosed and treated.24 for open reduction of fractures and during follow-up Patients with ankle fractures frequently have pain, examinations to monitor healing. swelling and an inability to bear weight on the affected Both conventional radiography and CT are consid- ankle. If the ankle is dislocated, it should be manipu- ered low-dose exams. The effective dose for radiogra- lated as soon as possible to restore the anatomy and phy of the extremities is about 0.01 mSv and 1.0 mSv for reduce risk of neurovascular compromise and skin a multidetector CT (MDCT) exam.25,26 It still is impor- necrosis. This reduction must be performed by a tant to minimize radiation exposure to the patient. trained clinician and adequate analgesia should be An important method for reducing exposure during given to the patient. The neurovascular status of the conventional radiography is to collimate the x-ray beam foot should be assessed both before and after the to the anatomic area of interest. This also reduces scat- manipulation. Radiologic technologists should ensure ter, which improves image contrast. Gonadal shielding that the joint is immobilized before imaging.11 also is required during extremity imaging because the Syndesmosis injuries often are associated with ankle shielding does not interfere with diagnostic informa- fractures and are important to detect because the liga- tion. This reduces the gonadal dose to ≈ 0. Radiologic ment structures are crucial for ankle stability.6 Patients technologists also should verify that female patients often have pain, ecchymosis (large purplish patch of are not pregnant before imaging to reduce the risk of blood under skin) and swelling in the lateral aspect of radiation exposure to the fetus. If it is necessary to per- the ankle, and are unable to bear weight on the affect- form an exam on a pregnant patient, the radiographer ed ankle. They also may have swelling on the medial should carefully position lead shields over her abdomen side when a deltoid injury or medial malleolus fracture and tightly collimate the x-ray beams.18 is present. An external rotation test may be performed to confirm a syndesmosis injury. It is performed by Radiography rotating the patient’s foot externally, which reproduces Based on the ring principle, it is likely that the pain at the ankle.6 patient with an ankle fracture has multiple injuries. When fracture is suspected, the American College Therefore, when a medial joint fracture is detected of Radiology (ACR) recommends using the Ottawa and the patient has associated lower leg pain, the

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Figure 2. Anteroposterior (AP) projection. The patient’s ankle is flexed with the foot placed vertically to the table. The central ray enters midway between the malleoli. Image courtesy of Jennifer G Hayden, MS, R.T.(R)(M), and Caroline B Goffena, MPH, R.T.(R)(MR), instructors at the University of North Carolina at Chapel Hill division of radiologic science.

entire lower leg may be radiographed with anteroposterior (AP) and lateral projections to rule out a fibula fracture.18,19 The ACR recommends AP, lateral and 15º to 20º internal oblique (mortise) projections with additional projections added in questionable cases.25 The additional projections may include a 45º internal oblique or an off-lateral and a 45º external oblique radiograph, which may help demonstrate the malleoli and the tibiofibular articulation.8,18 Stress studies of the ankle can verify the presence of a ligament tear.18 For a true AP projection, the radiologic technologist positions the patient supine on the exam table with Figure 3. True AP projection radiograph of the ankle the affected limb extended fully and no rotation. The demonstrating a lateral malleolus fracture. ankle joint should be flexed, with the long axis of the foot placed vertically to the table. The technologist should center the central ray midway between the mal- plate.18,23 This projection may demonstrate ruptured leoli and perpendicular to the ankle joint (see Figure ligaments or other types of separations if either the 2).18 When more of the leg needs to be imaged, the tibiofibular or talofibular articulations are shown in radiographer can use a larger cassette, but still should profile (see Figure 3). In a normal ankle, the tibio- center the central ray at the joint and place a flat con- fibular articulation overlaps the anterior tubercle and tact shield over the extended radiation field to prevent the talus slightly overlaps the fibula, but no there is no backscattered radiation from reaching the imaging overlapping of the medial talomalleolar articulation.18

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Rotating the ankle laterally or medially during patient positioning obscures the medial mortise. If the ankle is rotated laterally, the tibia and talus will be more superimposed over the fibula and the posterior aspect of the medial malleolus will be seen laterally to the anterior aspect. Medial rotation causes minimal superimposition of the fibula over the talus.23 The degree of openness of the tibiotalar joint also indicates whether the ankle is properly positioned. If the proximal lower leg is elevated, the anterior tibial margin will be projected distally, which results in a narrowed tibiotalar joint space. If the distal lower leg is elevated, the anterior tibial margin will be projected proximally to the posterior margin, which results in an expanded tibiotalar joint space. During dorsiflexion, the talus is wedged into the anterior tibial region, which results in a narrow- appearing joint space; during plantar flexion, the calcaneus is moved proximally, resulting in a talocalcaneal superimposition.23 Mediolateral or lateromedial positioning of the patient facilitates the lateral projection. For mediolateral positioning, the patient is supine and rotated toward the affected side until the ankle joint is lateral and the patella is perpendicular to the horizontal plane. The technologist should place a support under the patient’s knees to maintain this position18 and place the foot in dorsiflexion to prevent lateral rotation of the ankle. The central ray should enter the medial Figure 4. Lateral projection of the ankle. The talar domes are superim- malleolus and be projected perpendicular to the posed. The entire calcaneus and all the tarsal bones to the base of the fifth joint. For lateromedial positioning, the patient metatarsal are displayed. is supine with the body turned away from the affected side until the extended leg is lateral.23 This position offers improved detail because the joint is closer be parallel to the cassette. The lateral talar dome will to the cassette. The patella should be perpendicular appear proximal to the medial talar dome when the to the horizontal plane and, if necessary, the technolo- proximal tibia is further from the table than the distal gist should place a support under the patient’s knee. tibia. The medial talar dome will appear proximal to The perpendicular central ray should enter one-half the lateral dome if the distal tibia is further from the inch superior to the lateral malleolus.18 The technolo- table than the proximal tibia. Evaluating the height of gist should include the lower one-third of the tibia and the longitudinal arch can help determine which dome fibula, the entire calcaneus and all the tarsal bones to appears proximal. The navicular bone superimposes the base of the fifth metatarsal in the lateral radiograph. over most of the cuboid bone when the lateral dome is The medial and lateral talar domes should be superim- proximal and very little of the cuboid bone when the posed and the lateral malleolus should be seen more medial dome is proximal.23 inferior to the medial malleolus (see Figure 4).18,19 For the AP oblique projection of the mortise joint, If the talar domes are not superimposed, the lower the radiographer should place the patient in the supine leg or foot may be rotated or the lower leg may not position with the entire leg and foot angled 15º to 20º

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medially, until the intermalleolar plane is parallel with the cassette. The foot should be in dorsiflexion so that the plantar surface of the foot is perpendicular to the leg. The central ray should be perpendicular to the joint and enter midway between the malleoli (see Figure 5).18 On the AP mortise view, the mortise joint space should be uniform, with the lateral joint space visible and the fibula not overlapping the talus.18,19 When the ankle has been properly positioned, the space between the medial mortise and tarsi sinus (opening between the calcaneus and the talus) should be visible (see Figure 6). The ankle may be under-rotated if the tarsi sinus is not visible, and over-rotated if the tarsi sinus is visible but the medial mortise is closed.23 Widening of the joint space may be due to medial ligament rupture associated with a fracture.19 Figure 5. AP oblique medial rotation (mortise joint) ankle position. Note the mal- It is important that the lower leg be leoli are equidistant from the imaging plate, indicating adequate joint rotation. Image parallel with the exam table for proper courtesy of Jennifer G Hayden, MS, R.T.(R)(M), and Caroline B Goffena, MPH, visualization of the tibiotalar joint space. R.T.(R)(MR), instructors at the University of North Carolina at Chapel Hill division When accurately positioned, the anterior of radiologic science. margin of the distal tibia should be about 3 mm proximal to the posterior margin. When the proximal tibia is elevated, the joint space will extended and the ankle in dorsiflexion. The radiogra- appear narrowed or obscured. Elevating the distal tibia pher must turn the foot opposite the site of the injury makes the tibiotalar joint space appear expanded and and obtain an AP radiograph with the perpendicular demonstrates the tibial articulating surface.23 central ray passing midway between the malleoli.18 If The radiographer can obtain the 45º medial- the applied stress is too painful for the patient, the oblique projection with the patient supine and with physician or orthopedic surgeon may inject a local the affected limb fully extended and rotated internally anesthetic into the sinus tarsi.9 When a ligament has 45º. It is important that the foot remain in dorsiflex- ruptured on the side of the injury, the radiograph will ion so that the ankle is at nearly 90º flexion. The foot demonstrate a widening at the affected joint space.18 may be supported by a foam wedge. The central ray should pass perpendicularly midway between the mal- Computed Tomography leoli. The resulting radiograph clearly demonstrates According to the ACR, CT is not recommended tibiofibular syndesmosis and the distal tibia and fibula for initial evaluation of suspected ankle fractures. without superimposition over the talus. For the 45º However, CT has proven to be an effective diagnostic lateral oblique projection, the patient is positioned the tool in cases of high-energy multiple trauma or when same as for the medial oblique except the leg is rotated joint effusion is present without a visible fracture on externally 45º. This projection is useful for determining radiographs.25 CT also is frequently used for surgical fractures at the subtalar joint and the superior aspect treatment planning. of the calcaneus.18 Haapamaki et al reported that MDCT is superior Stress radiographs usually are requested when a to radiography in cases of multiple trauma or when patient has suffered an inversion or eversion injury. complex ankle fractures are suspected.27 Advantages of The patient is placed supine with the injured leg this modality are that ankle positioning is not critical

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ankle exams required 2 consecutive scans in perpendicular orientations. This technology can produce 3-D images in numerous planes from the raw isotropic data collected in 1 acquisition.7 The data can be reconstructed to any plane of choice for the reviewer, including axial, coronal, sagittal and infinite oblique planes. Patient positioning is not as critical because of the ability to reformat the data. This adds to patient comfort and reduces the need for repeat exams. These improvements over single-slice CT reduce the need for sedation of pediatric patients and lower radiation dose to the patient. The protocol for a pediatric ankle evaluation using 16-slice MDCT is 120 kV, 20 to 80 mAs (depending on patient weight), with 0.5 second rotation time, 0.75 mm collimation and 0.75 mm thick sections at 0.5 mm intervals. The raw data are trans- ferred to a workstation for reformatting into 3-D CT images. The entire process of 3-D manipulation of the data set and interpretation of the results usually takes less than 5 minutes.28 One study described MDCT as an important tool in evaluating musculoskeletal disease in pediatric patients. Children who are afraid benefit from shorter scan times. The exam is useful for defining the extent of displacement of the physeal component in Salter fractures or displacement involving the epiphyseal plate. Determining the extent of physeal displacement also assists in deci- sions regarding whether the patient will need internal fixation. Identifying when surgery is needed for Salter injuries is an added benefit of CT because the injuries are associated with growth arrest. CT also can be useful for follow-up to assess the development of deformities or premature physeal closure, compartment syndrome and ligament laxity.28 Techniques for manipulating CT data include volume rendering, shaded surface display and maxi- mum intensity projection. These techniques better Figure 6. Oblique projection of the ankle. The entire ankle display anatomic relationships and disease processes mortise joint is seen in profile. of soft tissues in the foot and ankle joints. One report stated that 2-D multiplanar reformatted images most often were used for diagnosis, especially of small and that it helps to demonstrate occult fractures and fractures. Volume rendering helps depict the relation- precise fracture anatomy.25 The researchers conducted ships between ankle tendons and the bony structures CT exams using 4 x 1.25 mm collimation, 0.625 mm beneath. When a fracture extends to the articular sur- intervals and 3.75 mm table speed with routine 2-D face, shaded surface display may be used to isolate the reformatting in standard coronal and sagittal planes fractured surfaces from overlapping structures.29 with a slice thickness of 1.0 mm and a reconstruction MDCT is useful for postoperative open reduction increment of 1.0 mm.27 and internal fixation evaluation. Streak artifacts due to The introduction of 16-slice MDCT has reduced x-ray attenuation from orthopedic hardware have been ankle CT exam time to less than 10 seconds. Previously, a problem in the past. The attenuation would lead to

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missing data on reconstructed axial images. With 3-D in a supine position and the affected extremity in a imaging, data reformation into other planes weights neutral position. The scan sequences used depend on the true signal over the randomly distributed artifact, the pathology in question. Fluid sensitive T2-weighted enhancing the true signal and reducing the metal-relat- fat-suppression and short T1 inversion recovery (STIR) ed artifact on volume-rendered 3-D CT images.28 sequences may demonstrate effusion. Gardner et al CT arthrography may be used to delineate cartilage used transaxial T2-weighted fast-spin-echo, sagittal covering and loose bodies within the joint. It also is an T1-weighted spin-echo, fast inversion recovery and coro- effective tool for diagnosing pediatric stress fractures nal fast-spin-echo imaging sequences. In the study, an because it demonstrates endosteal bone response, MR radiologist used the axial T2-weighted images to which may otherwise resemble a tumor.8 evaluate the syndesmotic, talofibular and deltoid liga- Atesok et al described the use of intraoperative ments to determine whether the ligaments were intact, CT imaging using the Siremobil Iso-C3D (Siemens partially torn or completely torn.33 Medical Solutions, Malvern, Pennsylvania).30 The MR imaging provides better spatial resolution and device is a mobile fluoroscopic C-arm with a specially specificity than CT for evaluating stress fractures and designed computerized image processing workstation. can detect minor stress reactions on a STIR sequence The C-arm has a motor unit that transports it steadily or fat-suppressed T2-weighted fast spin echo sequence.31 and continuously over a 190° arc for visualization of Muthukumar et al suggested a T1-weighted sequence and a 119 mm area. A set of 2-D fluoroscopic images in an edema-sensitive sequence or a T2-weighted sequence fixed angular steps is recorded during this rotation. with frequency-selective fat suppression for evaluating The images are transported from the C-arm to the stress fractures. The authors described the appearance hard disk and then to a computerized workstation. of a stress fracture as a line of low signal intensity on all Multiplanar CT images and a 3-D reconstruction set MR sequences. The most common pattern demonstrated are available 5 seconds after scanning. According to the was a fatigue-type fracture demonstrating the fracture study, surgeons could identify unacceptable reduction line surrounded by an ill-defined zone of edema. When and inappropriate position of joint fragments, enabling evaluating ankle stress injuries, MR best demonstrates them to make corrections during surgery instead of viability, bone marrow response and mechanical stability. having to perform a second surgery.30 MR also is noninvasive, uses no ionizing radiation and CT or MR imaging can determine the extent of a can be performed more quickly than scintigraphy.8 stress fracture and assist with treatment planning and follow-up. CT is less sensitive than MR but is useful for Scintigraphy determining the extent of the fracture and when surgi- Scintigraphy, or radionuclide bone scanning, can cal repair is required. A CT scan may show the disrup- show a stress fracture 1 to 2 weeks before it may be tion on the bony cortex and evidence of periostitis.31 detected radiographically but the modality is nonspe- cific.8 Little patient preparation is needed for these Magnetic Resonance Imaging exams. Patients are instructed to wear normal clothing, The usefulness of MR imaging to detect fractures but to remove all metal objects both outside and inside has been debated. Campbell and Warner stated, of the clothing so the objects do not cause artifacts that “MR imaging is exquisitely sensitive for detection of could appear as pathologic conditions on the images. fractures.”24 Remplik et al, however, found no statisti- Radioactive tracers are injected and localize in areas of cal difference in detection of acute fractures of the increased osteoblastic activity. The tracers emit gamma distal extremities between MR and conventional radi- rays that are detected with a gamma, or scintillation, ography.32 MR is used to evaluate ligament or tendon camera. The camera transforms the gamma emissions injuries associated with ankle fractures8,24 and is an into images that are recorded on a computer or film. effective tool for evaluating questionable joint stabil- The radiopharmaceuticals commonly used to evalu- ity. Gardner et al found that the appropriate clinical ate bone pathology are technetium Tc 99 hydroxymeth- application of MR findings still is unclear because of ylene diphosphonate 99 and 99mTc methylene diphos- the debate regarding which combination of ligament phonate. The adult dose is 20 mCi (740 mBq) and the injuries results in joint instability.33 pediatric dose is adjusted according to the patient’s MR imaging of the ankle is performed with an weight. The time between injection of the radiophar- extremity coil. The technologist should place the patient maceutical and the bone scan is 2 to 3 hours and the

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scan takes approximately 30 to 45 minutes.34 Differential of ankle fractures.33 The system is based on foot posi- diagnoses may include bone infection or tumor.7 tion (pronate or supinate) and the direction of force applied (adducting, abducting or externally rotating) Ultrasonography at the time of injury.21,37 It was derived after studying Ultrasonography is an effective tool for evaluating cadaver feet placed under different stresses and in dif- bony avulsion at a ligamentous insertion and ankle liga- ferent positions. Lauge-Hansen determined that injury ment integrity. It is much less expensive than MR imag- to the ligaments and bones occurred in a predictable ing for evaluating the same anatomic region, costing sequence when placed under a deforming force.37 The only 19% of the professional and technical fees charged time at which the deforming force ceases during the for MR. Inversion injuries often result in lateral ankle injury sequence determines the degree of injury.37 The ligament tears, most commonly the anterior talofibular 4 basic mechanisms of injury described by the Lauge- ligament, followed by the calcaneofibular ligament. Hausen system are21,37: Additionally, chronic ankle joint instability may result ■ Supination-adduction. from sprains. The diagnostic accuracy of ultrasound for ■ Supination-inversion. anterior talofibular tears has been reported to be 90% to ■ Pronation-abduction. 100%. Accuracy is lower for calcaneofibular tears (87% ■ Pronation-external rotation. to 92%) and anterior tibiofibular tears (85%).35 Another type of injury later was added to the system Three categories have been created for ultrasound to describe the mechanism for tibial plafond fractures, classification of sprains. Mild acute sprains result in a called the pronation dorsiflexion injury.21 A drawback normal or slightly thickened ligament. The moderate to this classification scheme is the difficulty patients to severe (partial tear) sprains show an anechoic area have stating exactly how their foot was positioned at the where partial interruption in the ligament has occurred moment of injury.37 and the ligament remains taut on examination. In the A study by Gardner et al found that of the 59 ankle complete ligamentous tear, there is a complete avulsion fractures they evaluated, only 49 fit into Lauge-Hansen of fibers appearing as a hypoechoic gap.36 categories and that 26 of these had ligament injuries Regardless of the modality used, careful elicitation that were not predicted by the Lauge-Hansen scheme.33 of the patient history and clinical findings are key to The authors compared MR images with radiographs image analysis.8 Alternative diagnoses to ankle fracture to determine the extent of soft-tissue injury in these include tendonitis, strain, sprain, claudication, infec- patients. They suggested using the Lauge-Hansen tion and tumor.33 system simply as a guide for the diagnosis and management of ankle fractures and using MR imaging to Classification of Ankle Fractures evaluate atypical injuries and plan surgical treatment.33 According to Skinner, “The purpose of any classi- Arimoto and Forrester devised an algorithm based on fication scheme is to provide a means to better under- the Lauge-Hansen system to improve the diagnostic use- stand the extent of injury, describe an injury, and deter- fulness for radiologists.37 They determined that the direc- mine a treatment plan.”21 Neither the Lauge-Hansen tion of deforming force could be derived from reviewing nor the Weber classification system encompasses all the radiograph for the presence and location of a fibula fracture types.21 Isolated fractures of the talus, stress fracture, including its location in relation to the tibial fractures and pathologic fractures are some examples plafond and the direction of the fracture. The medial that are not included in these schemes.20,21 The Salter- and posterior malleoli then were evaluated to help estab- Harris anatomic system commonly is used to classify lish the type of force applied and degree of injury com- pediatric ankle fractures.13 Ankle fracture dislocations pleteness. The authors claimed that the algorithm helps may be called bimalleolar when the medial and lateral radiologists accurately diagnose fractures and ligament malleoli are involved and trimalleolar when the poste- tears based solely on the radiographic exam even without rior malleolus also is fractured.21 full knowledge of the mechanism of injury.37

Lauge-Hansen Danis-Weber The Lauge-Hansen system was created to enable The more current and less cumbersome Weber clas- prediction of the mechanism of injury and pattern of sification scheme is based on the location of the fibula ligament injury based on the radiographic appearance fracture and is divided into 3 basic fracture types.

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■ Type A. An avulsion fracture of the fibula distal to follow, and focal trabecular microfractures occur. They the joint line with the syndesmotic ligament left can progress to a linear stress fracture and a periosteal intact and the medial malleolus either normal or or endosteal response.31 Stress fractures often present with a shear-type fracture pattern. with vague, poorly localized and aching-type pain.1 ■ Type B. A spiral fracture of the fibula extend- They are common in sports that cause repetitive load ing from the joint line in a proximal-posterior to the lower extremity, such as track and field, distance direction up the fibular shaft. The tibiofibular running, court-based sports and dancing.31 Factors that joint syndesmosis is usually intact. The medial or have been associated with the etiology of stress fractures posterior malleoli may sustain avulsion fractures include an underlying medical disorder, lack of flexibil- or be intact. When the medial malleolus is not ity, poor strength or muscle imbalance, rapid changes fractured, the deltoid ligament may be torn. in athletic training, increased physical activity, failure ■ Type C. A fibula fracture proximal to the syndes- to wear proper shoes while exercising, diet and artificial motic ligament complex with disruption of the training surfaces or switching from one type of training syndesmosis. The medial malleolus also includes an surface to another.1,8,31 avulsion fracture or deltoid ligament rupture; a pos- Symptoms usually develop over the course of 2 terior malleolus avulsion fracture may be present. to 3 weeks, but may occur sooner or last longer. The Posterior malleolar fractures also may be classified patient may have localized pain, redness, swelling and as the posterior-oblique type, medial-extension type or warmth and palpable periosteal new bone with reduced the small-shell type. One study reported that CT was adjacent joint movement upon physical examination.8 preferred over radiography for determining the size Some bimalleolar and trimalleolar fractures now are of a posterior malleolar fracture fragment because the regarded as osteoporotic because they occur more angle of the fracture line is highly variable and the often in older women and follow the same pattern as fracture lines often are irregular.38 fragility fractures.5 Radionuclide bone scans may help to evaluate stress fractures because the fractures rarely Other Types of Fractures are seen on conventional radiographs.1 The sensitivity Ankle fractures that are not included in the Lauge- of radiography is only 15% to 35% for initial evaluation Hansen or Weber schemes include fractures of the of stress fractures and 30% to 70% during follow-up. lateral process of the talus (a common snowboarding Whether the stress fracture is detected depends on how injury), stress fractures of the distal tibia or distal fib- much time has elapsed since the injury developed and ula and medial malleolus and pathologic fractures.1,20 the type of bone involved. These fractures are easier to Lateral process fractures of the talus usually result detect in cortical bone than cancellous bone.8 from an external rotation force while the ankle is in fixed dorsiflexion and inversion. There are 3 basic Salter-Harris types of lateral process fractures of the talus1: The Salter-Harris classification system divides ■ Type I. An extra-articular fracture of the ante- injury patterns in skeletally immature patients into rior/inferior aspect. types I through type V (see Figures 7 and 8). They are ■ Type II. A nondisplaced simple fragment extend- described as follows13: ing from the talofibular joint surface to the ■ Type I. This is a physeal injury without radio- posterior subtalar joint surface. Type IIB helps to graphic evidence of bony injury. differentiate a displaced fragment with the Type ■ Type II. Has a fracture line that extends trans- II pattern. versely through the physis and exits proximally ■ Type III. A comminution of both the fibular and through the metaphysis. posterior subtalar articulating surfaces. ■ Type III. The fracture line transverses the physis These fractures are best demonstrated on lateral and exits distally through the epiphysis. and internal oblique radiographs and CT.1 ■ Type IV. The fracture line traverses the epiphysis A stress fracture may be partial or complete and is and physis and exits the metaphysis. caused by the repetitive application of stress at a level ■ Type V. This is a crush injury to the physis.13 lower than the amount required to fracture the bone in Injuries to the syndesmosis are common with a single loading. Stress fractures begin with an increased ankle fractures and are divided into types I through rate of osseous remodeling. Resorption and rarefaction III. A type I syndesmosis injury presents with normal

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Figure 7. AP projection of a healing Salter-Harris III fracture. Figure 8. Lateral projection of the same healing Salter-Harris Sclerosis is seen around the epiphyseal fracture in the distal III fracture. Image courtesy of Jennifer G Hayden, MS, R.T.(R) medial tibia. Image courtesy of Jennifer G Hayden, MS, R.T.(R) (M), and Caroline B Goffena, MPH, R.T.(R)(MR), instructors (M), and Caroline B Goffena, MPH, R.T.(R)(MR), instructors at the University of North Carolina at Chapel Hill division of at the University of North Carolina at Chapel Hill division of radiologic science. radiologic science.

alignment of the ankle and stability is maintained Treatment on supine inversion/eversion stress views. A type II Several methods are available for managing ankle appears stable on nonstressed views, but demonstrates fractures. Most emphasize the importance of early widening and instability on stress views. The type III and accurate reduction of the joint and initiation of shows widening of the medial clear space and often joint motion as soon as possible. Jelinek and Porter widening at the tibia-fibula articulation.13 described the priorities for managing ankle injuries. They stated that the ankle first should be evaluated Pathologic Fractures for adequate blood flow, which is demonstrated by Pathologic fractures are caused by bone tumors or normal flesh color and palpable pulses. Provisional osteoporosis and occur spontaneously or with little stress reduction of marked deformity or dislocation should on the bone. Most primary bone tumors are malignant. be completed next. This may be performed on site by Osteosarcoma, Ewing sarcoma and chondrosarcomas a trained emergency responder or by a physician in are some examples of primary bone tumors. Treatment the emergency department. Next, a clinician should of primary bone tumors often requires amputation care for open wounds or soft-tissue injuries. It is only or excision, sometimes followed by chemotherapy. after these issues have been addressed that precise Secondary bone tumors usually result from metastatic reduction of skeletal deformity and repair of any asso- spread of breast, lung or prostate cancers.20 ciated injuries can take place. Rehabilitation and the

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care of potential complications are the final steps in et al reported that they treated Weber A injuries with fracture management. Jelinek and Porter wrote that retrograde intramedullary 4.5mm or 5.5 mm can- joint mobilization as soon as possible, without compro- nulated screw fixation after anatomic reduction.40 mising the reduction, is key to achieving an optimal Clinicians may choose to follow up patients with these functional outcome.13 fractures to be certain no talar shift occurs.11 Others have reported similar management, but spe- If a fracture is potentially unstable, such as an iso- cifically that 4 criteria must be met for optimal treat- lated Weber B or C fracture, the patient’s ankle may be ment. The first criterion is to reduce dislocated frac- placed in a below-knee back slab to allow for swelling. A tures as soon as possible. Next, all joint surfaces should back slab has a plaster back that extends from the tibial be restored precisely. The fracture then must be held tubercle posteriorly to the calf, ankle, heel, sole and in a reduced position during the period of bony heal- toes. The slab is left open on top to allow for swelling, ing.21 Lastly, joint motion should be initiated as early as but a soft bandage is wrapped around the back slab possible, although there is debate over exactly when to and anterior portion of the lower leg and ankle to keep initiate motion.5,21 it in place. After a 1-week follow-up appointment with According to Gardner et al, “The first decision imaging of the ankle to ensure adequate positioning of to make when treating ankle fractures is whether the joint, the back slab usually is replaced with a light- surgical reduction and fixation are necessary. The weight cast. Immobilization with no weight bearing for most important underlying factor in this decision is the initial 6 to 8 weeks is required.11 whether the ankle is stable or unstable.”39 Bimalleolar, Unstable injuries that require surgical stabilization trimalleolar, fracture-dislocations and some isolated include bimalleolar or trimalleolar fractures, dislocated fibula fractures that present with more than 5 mm of fractures and lateral malleolar fractures with deltoid lig- medial clear-space widening or syndesmotic widen- ament injury, syndesmosis injury or talar shift. Surgery ing radiographically are considered unstable.10 The to restore the fibular length and mortise integrity should integrity of the ligament structures is important for be carried out as soon as possible or once significant determining overall ankle joint stability. Stable frac- swelling has subsided. During surgery, the syndesmosis tures usually are treated successfully with conservative is evaluated clinically and with fluoroscopic imaging. care, but unstable fractures require internal fixation When instability of the syndesmosis is suspected, repair to maintain joint reduction until the fracture(s) have may be performed by passing 1 or 2 screws from the dis- healed.39 A consideration in treating athletes is how tal fibula to the tibia (see Figures 9 to 11).11 rapidly the patient desires a safe return to sports, and Jelinek and Porter described treating Weber B inju- surgery often establishes stability sooner. The type of ries with anatomic reduction and anterior-to-posterior hardware chosen for surgical fixation depends on the lag screw fixation, and a posterolateral one-third semi- degree and type of injuries.13 tubular antiglide plate. They also described stabilizing Approximately 25% of ankle fractures are treated the fibula for Weber C injuries with a lateral plate and with surgical stabilization each year in the United States.3 occasionally a 2.7 mm or 3.5 mm lag screw; the plate When surgery is indicated for treatment, it is best per- thickness depends on the amount of comminution formed as soon as possible to reduce the risk of complica- and length of fracture. When the syndesmosis remains tions, such as blistering or swelling, and extra costs of an unstable to external rotation stress the authors recom- extended hospital stay. One study reported that the total mend placing 1 to 2 cannulated syndesmosis screws (size length of hospital stay for patients undergoing surgery 4.5 mm) through the lateral fibular plate and across the within 48 hours of diagnosis was 5.4 days, compared with 3 cortices. They also use these techniques for bimalleo- 9.5 days when surgery was delayed more than 48 hours.4 lar fractures with additional direct repair of the deltoid Surgical risk factors include infection and reaction to the ligament, which is achieved with 2 size 1 Vicryl (Ethicon osteosynthetic material used to correct the fracture.5 Inc, Somerville, New Jersey) absorbable horizontal Patients with stable undisplaced fractures, such mattress sutures in the deep deltoid and 2 size 0 Vicryl as isolated Weber A or B fractures with no talar shift sutures in the superficial deltoid.13 Patients should not or medial joint tenderness, often are given an ankle fully bear weight for 6 to 12 weeks following deltoid liga- brace or elastic support for comfort and are encour- ment repair, at which time the screws are removed.11,13 A aged to fully bear weight immediately.11 A wide variety below-knee cast is applied and patients are encouraged of hardware is available for surgical fixation. Porter to elevate the foot to prevent swelling. Some clinicians,

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Figure 9. Fluoroscopic AP image taken during open reduction Figure 10. Fluoroscopic lateral image taken during open reduc- and internal fixation of a bimalleolar ankle fracture. The medial tion and internal fixation surgery. Image courtesy of Jennifer and lateral malleolar fractures have been reduced and internally G Hayden, MS, R.T.(R)(M), and Caroline B Goffena, MPH, fixed with retrograde malleolar screws. Image courtesy of Jennifer R.T.(R)(MR), instructors at the University of North Carolina at G Hayden, MS, R.T.(R)(M), and Caroline B Goffena, MPH, Chapel Hill division of radiologic science. R.T.(R)(MR), instructors at the University of North Carolina at Chapel Hill division of radiologic science.

however, recommend early mobilization in an ankle medial malleolus fracture is present. Advantages to brace when a strong fixation has been achieved.11 this approach stem from the direct visualization of Open reduction and internal fixation of posterior the posterior fragment, which promotes anatomical malleolar fractures is recommended when the posteri- reduction and better inspection for osteochondral or fragment is more than 25% to 30% of the tibial pla- fragments and talar chondral damage. The approach fond. There are 3 surgical approaches: lateral, medial also allows the orthopedic surgeon to clean the frac- and posterolateral. The most direct access is achieved ture of interposed callus or periosteum when surgery using the posterolateral approach. When the fracture has been delayed.41 line extends all the way to the medial malleolus, the Open fractures must be treated with debridement, medial approach is best.38 irrigation, antibiotics and internal fixation. Because Talbot, Steenblock and Cole described a technique of the likely contamination of these wounds, intra- for fixation of trimalleolar ankle fractures.41 They venous broad-spectrum antibiotics may be required. stated that repair of the posterior malleolus is indi- Complications for these wounds include swelling, infec- cated when the fracture involves more than 25% to tion and soft tissue loss, which may inhibit skin closure 35% of the distal tibia’s articular surface. Instead of over the orthopedic hardware.11 using the more standard supine approach to access Treatment of stress fractures includes rest, flexibility the posterior fragment, they suggested using a pos- exercises and use of nonsteroidal anti-inflammatory terolateral approach in which the patient is placed drugs (NSAIDs). Return to activity is progressive and in the prone position with a bolster under the ipsi- usually takes 6 to 12 weeks. A chronic nonunion frac- lateral hip or in the lateral decubitus position if no ture may require surgery and bone grafting.1

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They support the use of a removable brace because patients have been shown to return to normal activity sooner and because, unlike casts, braces do not require special orthopedic services for placement or removal.9 When physeal injuries occur, however, open reduction and internal fixation may be required to decrease the risk for physeal arrest and enhance articular congruity. Surgery is recommended when displacement is > 2 mm at the articular surface or 3 to 4 mm at the physes after closed reduction or if any rotational or angular deformity is present.13 Age is a predictor of outcome. One study determined that patients older than 40 years had a less functional recovery than younger patients. Another study claimed it was more important for elderly patients to recover function of the ankle joint as quickly as possible because bone mass density, proprioception and muscle force already reduced because of their age. Severely dislocated fractures also have a poorer prognosis.5 Diabetes increases the rate of in-hospital mortality, in-hospital postoperative complications, length of hospital stay and the Figure 11. Fluoroscopic oblique image taken during open total cost of treatment for ankle fractures. On average, reduction and internal fixation surgery. The ankle mortise patients with diabetes are in the hospital 1 day longer appears symmetric. Image courtesy of Jennifer G Hayden, MS, than patients without diabetes and incur approximately R.T.(R)(M), and Caroline B Goffena, MPH, R.T.(R)(MR), $2000 more in charges for treatment.3 instructors at the University of North Carolina at Chapel Hill division of radiologic science. Rehabilitation and Functional Recovery A wide variety of rehabilitation interventions are available, with the goal of obtaining functional recovery of the joint.2,13 According to Egol et al, factors pre- Lateral process fractures of the talus usually are dicting functional recovery at 1 year include younger repaired with open reduction and internal fixation age, male sex and absence of diabetes.10 A review of when the fracture is displaced by more than 1.5 cm. current intervention techniques found that there is This is followed by wearing a short-leg cast for 4 weeks no consensus regarding which immobilization device before beginning flexibility exercises. Weight bearing works best, when weight bearing ideally should begin is encouraged when osseous union is detected, usually or how effective postimmobilization stretching and at about 4 to 6 weeks after injury. Nondisplaced type I manual therapy are. This review reported that after and II fractures usually are immobilized for 6 weeks. surgical fixation, beginning exercise while in a remov- Gehrmann recommended excising a lateral process able brace improved activity limitation but also led to a fracture of the talus involving significant cartilage higher rate of adverse events.2 damage or one that is < 1.5 cm comminuted. Long- term complications from these fractures include pain Initial Rehabilitation with weight bearing and degeneration of the subtalar Rehabilitative exercises may begin during or fol- joint, impingement in the sinus tarsi or talofibular joint lowing immobilization, depending on joint stability and symptomatic nonunion.1 and whether open reduction and internal fixation was Casts still are used widely in pediatric patients for required.2,13 Postoperative rest, use of ice, compres- low-risk fractures of the ankle. The casts usually remain sion and elevation of the ankle help decrease swelling on the child for 3 to 4 weeks. Some authors suggest this and reduce pain.13 Gentle exercise or weight bearing, is unnecessary and expensive, and may present greater manual therapy and more rigorous exercise may be complications than those associated with the fracture. prescribed.2,13 Egol et al recommended bearing weight

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6 weeks after surgery when a syndesmotic screw has arthrofibrosis, and reduces the time to achieve func- been placed unless the patient requested removal of tional recovery. Passive range of motion is performed the screw.10 In that case, the authors suggested an addi- by relaxing the muscles while the joint is mobilized, tional 4 weeks of nonweight-bearing activity. They also whereas active range of motion engages the muscles. It required patients with diabetes to wait an additional 2 is important to work range of motion in the opposite to 4 weeks after syndesmotic screw placement to begin direction from the mechanism of injury to protect the weight-bearing activity.10 ligament until it heals. Patients must gain range of Farsetti et al suggested that immediate use of con- motion in the rehabilitation process before strengthen- tinuous passive motion (CPM) after open reduction ing exercises can begin.13 and internal fixation of ankle fractures allowed for Weight bearing early in the recovery phase with the complete and quick recovery of range of motion and ankle protected in a brace or cast increases the stabil- decreased the risk of early degenerative joint disease. ity of the lateral ankle ligaments and decreases muscle In their study they used a CPM machine for at least 8 atrophy, joint stiffness and proprioception dysfunction. hours a day and overnight. When applied to the treated Types of strengthening exercises that may be intro- ankle, it alternated the foot and ankle between 5º of duced include isometric, isotonic and isokinetic.13 dorsiflexion and 10º of plantar flexion. Over a 2-week Additionally, proprioception exercises help to period, the passive movements were increased to maxi- decrease the chance of continued or recurrent injury. mum dorsiflexion and plantar flexion. At follow-up, Injury alters the normal proprioceptive mechanism the authors reported an average of 52º range of motion in the extremity, which comes from receptors in the in patients who received CPM compared with 34º for muscles, ligaments, tendons and receptors in the joint. the control group.42 Examples of these proprioception exercise techniques Obremskey et al reported that adult patients make include early weight bearing, double leg stance and significant improvements in functional return up to single leg stance.13 1 year after open reduction and internal fixation.43 In athletic patients, cardiovascular activities also are Functional factors they evaluated included mobility, an important part of recovery. The activities increase return to daily activities and work and emotional status. cellular metabolic levels and enhance blood flow to the Their study suggested that the most drastic improve- extremity. They also increase motivation and improve ments are made during the first 2 postoperative months, the athlete’s psychological well-being.13 but significant improvements are made in all areas for up to 6 months. Emotional status continued to improve Three-phase Approach for Unstable Injuries for up to 1 year. Being more than 50 years of age was Jelinek and Porter described a 3-phase process for related to a worse functional outcome and longer time postoperative rehabilitation of unstable ankle inju- until return to work, but did not correlate with increased ries in athletes. The first phase focuses on soft-tissue risk for complications in this study.43 Egol et al also inflammation and edema, and emphasizes pain con- reported their patients had significant improvement in trol, decreasing inflammation and restoring of joint functional recovery with little or no pain after 1 year. range of motion. They proposed placing the patient Patients who were older than 40 years, had diabetes and in a walking boot with a Cryo Cuff (Aircast, Austin, were women had delays in healing.10 Texas) for cold and compression immediately after sur- Another study by Egol et al evaluated the time it gery. The patient receives instructions to rest, elevate took for patients to recover braking function with a the ankle and use the Cryo Cuff while awake. The driving simulator after open reduction and internal fix- patient also is told to perform toe curls, knee bends ation of unstable ankle fractures. The authors reported and leg lifts every 1 to 2 hours to prevent thrombosis. that it took 9 weeks for patients to perform at the level At 1 week following surgery, the wound is evaluated of the control group.44 and the physician checks stability on radiographs. Jelinek and Porter found that early range of motion Additional activity, such as light biking, range of and weight bearing led to faster healing in athletes motion exercises, light resistive tubing exercises and who had undergone open reduction and internal fixa- stretching are prescribed. The patient may be told to tion. They reported that the benefit of early range of begin partial weight bearing with axillary crutches, motion is the controlled ligament stress, which stimu- which progresses to full weight bearing in a boot. At lates strength, decreases risk for muscle atrophy and about 2 weeks, when the patient can walk without a

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limp in the boot, a stirrup brace with an athletic shoe sensory neuropathy, delayed union, loss of reduction of replaces the boot and the biking program is increased the syndesmosis and infection.43 Patients with diabetes to 30 to 40 minutes per day. The brace should be worn and those who are elderly often have poorer outcomes. for 2 to 6 weeks during all types of activity, then only Open and comminuted fractures also have a higher during athletic activity for 6 to 12 more weeks, depend- rate of postoperative problems.11 Prolonged immobili- ing on the fracture type.13 zation may cause muscle atrophy, arthrofibrosis, carti- laginous degeneration and bone atrophy. The fear of Strengthening Exercises reinjury may limit patients’ return to preinjury activity 13 The second phase of rehabilitation includes flexibil- levels. ity and functional strengthening with cardiovascular A study by Saltzman et al suggested that proper align- conditioning, proprioceptive training and light sport- ment of the subtalar joint is crucial to long-term strength 45 specific functional training. Rehabilitation usually of the ankle. The authors stated that ankle arthritis is begins about 1 month after operative fixation. New associated with rotational ankle fractures and that it is exercises may include standing calf stretches, balancing relatively rare to develop primary ankle osteoarthritis 45 exercises, double-to-single leg calf raises, elliptical exer- because of ankle articular cartilage properties. cise and stair-climbing exercise. Resistive tubing exer- Thangarajah et al reported that postoperative infections are more prevalent in patients who smoke or who cises also may increase in repetition and include more 46 directions. The patient should use a stair or incline have had bimalleolar injuries. Superficial infections board for the calf-stretching exercises. The balancing were treated with oral antibiotics. Patients with a deep exercise program progresses from wearing a shoe to a infection, diagnosed through microbial confirmation bare foot on a hard surface and holding for 60 seconds. of an organism, were readmitted to the hospital and were treated with surgical washout and debridement, Soft surfaces or a balance board may be introduced 46 last. Bicycling exercises may be exchanged for elliptical removal of hardware or intravenous antibiotics. and stair-climbing exercises at this point.13 Conclusion Ankle fractures are common in people of all ages Return to Normal Activity and activity levels and in both sexes. Optimal treat- The third rehabilitative phase involves a gradual ment planning and delivery are made possible through return to sporting activity with maintenance of flex- detailed patient evaluation and understanding of the ibility and strength and proper body mechanics. This mechanism of injury. Quality diagnostic imaging, phase usually begins 2 months after surgery. The including radiography and appropriate use of other patient may transition into running exercises once he imaging modalities, aids in ankle fracture evaluation or she can use a stair-climbing or elliptical machine for and management. 30 minutes, 4 to 5 days a week without complication. The return to running and sport-specific functions 13 References should be gradual. 1. Gehrmann RM, Rajan S, Patel DV, Bibbo C. Athletes’ Regardless of a patient’s age, activity level and ankle injuries: diagnosis and management. Am J Othop. underlying disease or conditions, it is important to 2005;34(11):551-561. counsel patients and their families about the expected 2. Lin CWC, Moseley AM, Refshauge KM. Effects of functional recovery after an ankle injury. By identifying rehabilitation after ankle fracture: a Cochrane system- patients who are at risk of delayed or limited recovery, atic review [epub ahead of print]. Eur J Phys Rehabil Med. physicians can develop altered care strategies.10 2009;45(3):431-441. www.minervamedica.it/en/journals /europa-medicophysica/article.php?cod=R33Y2009N0 Complications 3A0431. 3. Ganesh SP, Pietrobon R, Cecilio WA, Pan D, Lightdale N, The risk of complication from ankle fracture Nunley JA. The impact of diabetes on patient outcomes depends on injury severity and quality of fracture after ankle fracture. J Bone Joint Surg Am. 2005;87(8):1712- 11,43 reduction and stabilization. Arthritic changes, stiff- 1718. ness, infection, malunion, nonunion, synostosis forma- 4. Pietzik P, Qureshi I, Langdon J, Molloy S, Solan M. Cost tion, deep vein thrombosis and thrombophlebitis are benefit with early operative fixation of unstable ankle frac- common complications. Surgical complications include tures. Ann R Coll Surg Engl. 2006;88(4):405-407.

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Anne M Scott, BSRS, R.T.(R), is a part-time writer and stay- at-home mother of 2 children in Cape Carteret, North Carolina. She has written 2 previous articles for Radiologic Technology titled Improving Communication for Better Patient Care and Thyroid Cancer in Adults. Ms Scott last worked as a radiologic technologist in the sports medicine clinic at Duke University Medical Center in Durham, North Carolina.

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