Menu

8. Foot and Ankle MCQs

Practice Set 64 of 353

This practice set contains high-yield board review questions covering key concepts in 8. Foot and Ankle. Each clinical scenario is designed to test your diagnostic and management skills relevant to this subspecialty.

Question 1261

Topic: 8. Foot and Ankle

A 30-year-old patient has a severe juxta-articular varus deformity of the distal tibia, making it impossible to draw an accurate mid-diaphyseal line on the short distal segment. The contralateral limb is also affected by a similar deformity. When planning the Distal Tibial Mechanical Axis (DMA), the surgeon must reference the ankle joint orientation line. What is the population average normal Lateral Distal Tibial Angle (LDTA) that should be used in this scenario?

. 87°
. 90°
. 85°
. 92°
. 80°

Correct Answer & Explanation

. 90°

Explanation

Correct Answer: BThis scenario falls under "Step 2: Drawing the Distal Tibial Mechanical Axis (DMA) and Ankle MOT," specifically Scenario C: "Distal Tibial Deformity with Abnormal Contralateral LDTA." The case states, "If the deformity is distal and the opposite leg is also abnormal (or amputated), you must use the population average normal LDTA, which is90°(though ranges from 86-92° exist, 90° is the standard, safe planning fallback). Draw the DMA from the center of the ankle, extending proximally at exactly 90° to the ankle joint line."Option A (87°) is incorrect; this is the normal MPTA and mLDFA.Options C, D, and E are incorrectas they do not represent the standard population average normal LDTA for planning in this specific scenario.

Question 1262

Topic: 8. Foot and Ankle

When analyzing a tibia with a multi-apical deformity using the mechanical axis method, how are the multiple Centers of Rotation of Angulation (CORAs) typically identified?

. By bisecting the mid-diaphyseal lines between each visible fracture callus.
. By drawing the proximal and distal mechanical axes and identifying their intersection with the mid-diaphyseal line of the intermediate segment.
. By assuming the CORA lies precisely at the center of the longest bone segment.
. By using the anatomical axes of the femur and talus extended infinitely.
. By measuring the maximum translational distance from the mechanical axis deviation line.

Correct Answer & Explanation

. By drawing the proximal and distal mechanical axes and identifying their intersection with the mid-diaphyseal line of the intermediate segment.

Explanation

In multi-apical deformities, the proximal and distal mechanical axes do not intersect the intermediate segment at a single point. CORAs are found at the intersections of the proximal/distal joint-reference axes with the mid-diaphyseal line of the intermediate segment.

Question 1263

Topic: 8. Foot and Ankle

During a comprehensive deformity analysis, the mechanical axis of the entire lower extremity must be determined. This axis is defined by a straight line connecting which of the following anatomical landmarks?

. Center of the femoral head to the center of the ankle joint.
. Center of the femoral head to the center of the knee joint.
. Anterior superior iliac spine to the center of the patella.
. Tip of the greater trochanter to the lateral malleolus.
. Center of the pelvis to the center of the talus.

Correct Answer & Explanation

. Center of the femoral head to the center of the ankle joint.

Explanation

The mechanical axis of the lower extremity is defined by a line connecting the center of the femoral head to the center of the ankle joint (talus). The mechanical axis of the femur specifically ends at the knee.

Question 1264

Topic: 8. Foot and Ankle

A 30-year-old male presents with a multi-apical tibial diaphyseal deformity

. How is the mechanical axis analysis of a multi-apical deformity best approached?

. By drawing a single mechanical axis line connecting the knee and ankle, ignoring the middle segments.
. By correcting the entire limb at the most proximal deformity level.
. By defining the mechanical axes of the proximal, distal, and each intercalary segment to find multiple CORAs.
. By performing a single closing wedge osteotomy at the apex of the largest deformity.
. By calculating the JLCA and making corrections purely intra-articularly.

Correct Answer & Explanation

. By defining the mechanical axes of the proximal, distal, and each intercalary segment to find multiple CORAs.

Explanation

Multi-apical deformities require identifying the mechanical or anatomic axis of all involved segments (proximal, distal, and intercalary). The intersections of these lines determine the precise locations of the multiple CORAs.

Question 1265

Topic: 8. Foot and Ankle

A 16-year-old undergoes a 5 cm tibial lengthening procedure using an Ilizarov frame. During the mid-distraction phase, the patient develops a new-onset foot drop and paresthesias over the dorsum of the foot. Which of the following is the most appropriate initial management?

. Immediate surgical exploration and nerve repair
. Stop distraction and partially shorten the frame
. Administer high-dose intravenous corticosteroids
. Perform an immediate targeted tendon transfer
. Remove the external fixator entirely and apply a cast

Correct Answer & Explanation

. Stop distraction and partially shorten the frame

Explanation

A developing foot drop during tibial lengthening indicates a stretch injury to the common peroneal nerve. The immediate initial management is to halt distraction and partially shorten the limb to relieve tension on the nerve.

Question 1266

Topic: 8. Foot and Ankle

A 45-year-old male presents with ankle malalignment following a distal tibia malunion. Radiographs reveal a mechanical lateral distal tibial angle (mLDTA) of 105°. What clinical deformity does this radiographic finding indicate?

. Ankle valgus
. Ankle varus
. Ankle procurvatum
. Ankle recurvatum
. Pure translational shortening

Correct Answer & Explanation

. Ankle varus

Explanation

The normal mLDTA is approximately 89°. An abnormally large mLDTA (e.g., 105°) means the lateral angle is increased, which tilts the tibial plafond medially, resulting in a varus ankle deformity.

Question 1267

Topic: 8. Foot and Ankle

A 16-year-old patient with severe proximal tibial valgus is undergoing gradual deformity correction utilizing an external fixator. During the distraction phase, the patient develops new-onset dorsal foot numbness and a foot drop. Tension on which structure is most likely responsible?

. Tibial nerve
. Sural nerve
. Saphenous nerve
. Common peroneal nerve
. Superficial peroneal nerve only

Correct Answer & Explanation

. Common peroneal nerve

Explanation

Gradual correction of a valgus knee stretches the lateral structures. The common peroneal nerve is highly susceptible to traction injury during this process, leading to sensory deficits on the dorsum of the foot and weakness in ankle dorsiflexion.

Question 1268

Topic: 8. Foot and Ankle

A 45-year-old male presents with medial compartment knee osteoarthritis and a varus deformity. Standing full-length radiographs reveal a mechanical axis deviation (MAD) passing through the medial compartment. His mechanical Lateral Distal Femoral Angle (mLDFA) is 87 degrees, and his mechanical Medial Proximal Tibial Angle (MPTA) is 87 degrees. The Joint Line Convergence Angle (JLCA) is measured at 7 degrees. What is the primary cause of his varus deformity?

. Distal femoral extra-articular deformity
. Proximal tibial extra-articular deformity
. Combined femoral and tibial diaphyseal bowing
. Intra-articular deformity due to cartilage loss and ligamentous laxity
. Ankle joint malalignment compensating at the knee

Correct Answer & Explanation

. Intra-articular deformity due to cartilage loss and ligamentous laxity

Explanation

The normal mLDFA (87-89 degrees) and MPTA (87-89 degrees) indicate that the bony anatomy of the femur and tibia is normal. The abnormally high JLCA (normal is 0-2 degrees) points to an intra-articular source of the deformity, such as medial cartilage loss or lateral collateral ligament laxity.

Question 1269

Topic: 8. Foot and Ankle

During gradual tibial lengthening of 6 cm using an Ilizarov frame, a patient develops increasing ankle pain and an apparent valgus deformity. Radiographs demonstrate proximal migration of the lateral malleolus. Which crucial technical step was most likely omitted during the index procedure?

. Proximal tibiofibular syndesmotic fixation.
. Release of the anterior compartment fascia.
. Distal tibiofibular syndesmotic fixation.
. Fibular osteotomy at the junction of the middle and distal thirds.
. Peroneal nerve decompression.

Correct Answer & Explanation

. Distal tibiofibular syndesmotic fixation.

Explanation

During massive tibial lengthening, the attached soft tissues pull the fibula proximally if it is not adequately secured. Prophylactic fixation of the distal tibiofibular syndesmosis with a screw or transfixing wire prevents proximal migration of the lateral malleolus, avoiding subsequent ankle valgus and instability.

Question 1270

Topic: 8. Foot and Ankle

A patient presents with a distal tibial extra-articular valgus deformity. Preoperative planning identifies the Center of Rotation of Angulation (CORA) at the level of the ankle joint line. To avoid an intra-articular osteotomy, the surgeon places the external fixator hinge precisely at the CORA, but performs the osteotomy 3 cm proximal to the joint line. According to Paley's Osteotomy Rule 2, what is the geometric consequence of this setup?

. Pure angulation without translation of the bone ends.
. Angulation with translation of the bone ends, leading to collinear mechanical axes.
. Angulation with translation of the bone ends, leading to parallel but non-collinear mechanical axes.
. Pure translation without angulation.
. Creation of an iatrogenic multi-apical deformity.

Correct Answer & Explanation

. Angulation with translation of the bone ends, leading to collinear mechanical axes.

Explanation

Paley's Rule 2 states that if the osteotomy is placed outside the CORA but the hinge is at the CORA, the bone ends will translate relative to each other, but the mechanical axes will re-align perfectly (collinear).

Question 1271

Topic: 8. Foot and Ankle

A 40-year-old male presents with chronic ankle pain and progressive varus deformity of the ankle, leading to medial gutter impingement. Preoperative planning for a supramalleolar osteotomy (SMOT) requires precise measurement of the frontal plane ankle orientation. Based on the case, which angle is the primary target for correction in this scenario?

. A. Medial Proximal Tibial Angle (MPTA)
. B. Mechanical Lateral Distal Femoral Angle (mLDFA)
. C. Lateral Distal Tibial Angle (LDTA)
. D. Anterior Distal Tibial Angle (ADTA)
. E. Posterior Proximal Tibial Angle (PPTA)

Correct Answer & Explanation

. C. Lateral Distal Tibial Angle (LDTA)

Explanation

Correct Answer: CThe correct answer is C, the Lateral Distal Tibial Angle (LDTA). The case explicitly states that the LDTA is formed when the frontal plane ankle joint orientation line (across the tibial plafond) intersects the mechanical axis of the tibia. A normal LDTA ranges from 86° to 92° (average ~89°). An LDTA less than 86° indicates distal tibial varus, which shifts contact pressures medially and aligns with the patient's presentation of ankle varus deformity and medial gutter impingement. The text further emphasizes that 'Correcting the LDTA is a primary goal in supramalleolar osteotomies (SMOT).'Option A (MPTA)assesses proximal tibial alignment (normal 85-90°) and is relevant for knee deformities, not ankle varus.Option B (mLDFA)assesses distal femoral alignment (normal 85-90°) and is relevant for knee deformities, not ankle varus.Option D (ADTA)is the Anterior Distal Tibial Angle. This angle assesses sagittal plane ankle orientation (normal 78-82°) and is relevant for procurvatum/recurvatum deformities, not frontal plane varus.Option E (PPTA)assesses sagittal plane proximal tibial alignment (normal 77-84°) and is relevant for knee kinematics and ligamentous stability, not frontal plane ankle varus.

Question 1272

Topic: 8. Foot and Ankle

A 35-year-old male presents with chronic posterior ankle pain and limited plantarflexion. Radiographic evaluation reveals an Anterior Distal Tibial Angle (ADTA) of 70°. Based on the case, what is the most likely sagittal plane deformity and its clinical implication?

. A. Distal tibial varus, leading to medial impingement.
. B. Distal tibial valgus, leading to lateral impingement.
. C. Ankle procurvatum, leading to anterior impingement and loss of dorsiflexion.
. D. Ankle recurvatum, leading to posterior impingement and loss of plantarflexion.
. E. Normal ankle alignment, requiring further investigation for pain etiology.

Correct Answer & Explanation

. D. Ankle recurvatum, leading to posterior impingement and loss of plantarflexion.

Explanation

Correct Answer: DThe correct answer is D. The case states that the normal ADTA (Anterior Distal Tibial Angle) ranges from 78° to 82° (average ~80°). An ADTA of 70° is significantly decreased from the normal range. The clinical implication section for ADTA explicitly states: 'If the ADTA is decreased (e.g., <75°), the joint is in recurvatum, leading to posterior impingement and loss of plantarflexion.' This perfectly matches the patient's symptoms of chronic posterior ankle pain and limited plantarflexion.Option Adescribes a frontal plane deformity (distal tibial varus) associated with an abnormal Lateral Distal Tibial Angle (LDTA), not ADTA.Option Bdescribes a frontal plane deformity (distal tibial valgus) also associated with an abnormal LDTA, not ADTA.Option Cdescribes ankle procurvatum, which occurs when the ADTA isincreased(e.g., >85°), leading to anterior impingement and loss of dorsiflexion. This is the opposite of the patient's ADTA and symptoms.Option Eis incorrect because an ADTA of 70° is clearly outside the normal range, indicating a significant deformity.

Question 1273

Topic: 8. Foot and Ankle

A 40-year-old male presents with chronic ankle pain and progressive stiffness following a malunited distal tibial fracture 3 years prior. Radiographs reveal a distal tibial recurvatum deformity. The image provided demonstrates the biomechanical consequences of this deformity. Based on this, what is the most significant factor contributing to the rapid progression of ankle arthrosis in this patient?

. Increased shear forces on the deltoid ligament due to valgus stress.
. Chronic stretching of the Achilles tendon, leading to equinus contracture.
. Anterior translation of the talus, leading to uncovering and focal posterior loading.
. Compensatory subtalar joint eversion, causing hindfoot instability.
. Increased contact pressure on the anterior aspect of the talar dome.

Correct Answer & Explanation

. Anterior translation of the talus, leading to uncovering and focal posterior loading.

Explanation

Correct Answer: CThe image and text clearly explain that a recurvatum deformity of the distal tibia anteriorly tilts the tibial plafond. To achieve a plantigrade foot, the patient must compensate by forcing the ankle into continuous plantar flexion (equinus). This compensatory equinus position has two disastrous biomechanical consequences: it slides the wider, more stable anterior portion of the talar dome out from under the tibial plafond (uncovering the talus), and it forces the entire body's weight onto a much smaller, less congruent posterior contact area of the joint. This massive increase in peak contact stress on the posterior aspect of the joint is a primary driver of rapid, irreversible post-traumatic ankle arthrosis.Option A is incorrectbecause recurvatum is a sagittal plane deformity, and while it can have complex effects, the primary issue described is axial loading, not primarily deltoid ligament shear or valgus stress.Option B is incorrectbecause while equinus compensation occurs, the primary destructive mechanism is the altered joint contact mechanics, not solely Achilles tendon stretching.Option D is incorrectbecause subtalar joint eversion is typically a compensation for a varus tibial deformity, not recurvatum, and its loss, rather than its presence, is usually problematic.Option E is incorrectbecause the recurvatum deformity, with compensatory equinus, leads toposteriorfocal loading, as the anterior talar dome is uncovered and slides out from under the plafond. The anterior aspect is unloaded, while the posterior aspect is overloaded.

Question 1274

Topic: 8. Foot and Ankle

A 55-year-old male with a history of a malunited distal tibial fracture now presents with progressive ankle pain. Radiographs show a distal tibial varus deformity. The subtalar joint is noted to be stiff due to post-traumatic arthrofibrosis. The image provided illustrates the compensatory mechanism of the subtalar joint. Given the patient's stiff subtalar joint, what is the most likely consequence for his ankle joint?

. The subtalar joint will hyper-evert, leading to a planovalgus foot deformity.
. The ankle joint will be protected from abnormal forces due to increased subtalar stability.
. The lack of subtalar compensation will lead to direct transmission of abnormal forces to the ankle mortise, accelerating tibiotalar arthrosis.
. The patient will develop a compensatory genu valgum to maintain a plantigrade foot.
. The varus deformity will be effectively masked, preventing progression of ankle arthritis.

Correct Answer & Explanation

. The lack of subtalar compensation will lead to direct transmission of abnormal forces to the ankle mortise, accelerating tibiotalar arthrosis.

Explanation

Correct Answer: CThe text explains that 'a healthy, mobile subtalar joint is the ankle's best defense mechanism. It acts as a multi-axial torque converter, allowing the hindfoot to invert or evert to keep the sole of the foot flat on the ground, even in the face of significant tibial deformity.' The image shows how the subtalar joint everts to compensate for a varus tibia. The problem arises when this compensatory motion is lost, as in this patient with a stiff subtalar joint. Without the ability to compensate, the abnormal forces from the distal tibial varus deformity are directly transmitted into the rigid ankle mortise, significantly accelerating tibiotalar arthrosis.Option A is incorrectbecause a stiff subtalar joint means it cannot hyper-evert; it loses its ability to move and compensate.Option B is incorrectbecause a stiff subtalar jointpreventsthe protective compensatory motion, leading to increased, not decreased, abnormal forces on the ankle joint.Option D is incorrectbecause compensatory genu valgum would be a proximal compensation, not a direct consequence of a stiff subtalar joint in the context of a distal tibial deformity. The immediate impact is on the ankle joint itself.Option E is incorrectbecause the lack of compensation means the varus deformity isnotmasked; instead, its destructive effects are amplified at the ankle joint.

Question 1275

Topic: 8. Foot and Ankle

A 50-year-old patient presents with a complex tibial deformity following a high-energy pilon fracture. The surgeon is meticulously measuring joint orientation angles on a full-length standing radiograph. The Lateral Distal Tibial Angle (LDTA) is measured at 82°. The Posterior Proximal Tibial Angle (PPTA) is 81°. What is the most accurate interpretation of these specific findings?

. The patient has a normal ankle mortise orientation and an increased posterior tibial slope.
. The patient has an ankle varus deformity originating from the tibia and a normal posterior tibial slope.
. The patient has an ankle valgus deformity originating from the tibia and a decreased posterior tibial slope.
. Both the ankle mortise and the posterior tibial slope are within normal limits.
. The deformity is primarily in the proximal tibia, not affecting the ankle.

Correct Answer & Explanation

. The patient has an ankle varus deformity originating from the tibia and a normal posterior tibial slope.

Explanation

Correct Answer: BLet's analyze the given angles:Lateral Distal Tibial Angle (LDTA):Measured at 82°. The normal range for LDTA is 86° to 92° (average 89°). An LDTA less than 86° indicates an ankle varus deformity originating from the tibia. Therefore, 82° signifies an ankle varus deformity.Posterior Proximal Tibial Angle (PPTA):Measured at 81°. The normal range for PPTA is 77° to 84° (average 81°). A PPTA of 81° is perfectly within the normal range, indicating a normal posterior slope of the tibial plateau.Combining these, the patient has an ankle varus deformity originating from the tibia and a normal posterior tibial slope.Option A is incorrectbecause the LDTA is abnormal (ankle varus), and the PPTA is normal, not increased.Option C is incorrectbecause the LDTA of 82° indicates varus, not valgus, and the PPTA is normal, not decreased.Option D is incorrectbecause the LDTA is outside the normal range.Option E is incorrectbecause the abnormal LDTA directly indicates a deformity affecting the ankle mortise, originating from the distal tibia.

Question 1276

Topic: 8. Foot and Ankle

A 58-year-old male presents with progressive right knee pain and a noticeable bowing of his leg. A full-length standing anteroposterior radiograph of the lower extremity is obtained, as shown below. Based on this image, which of the following statements regarding the patient's mechanical axis deviation (MAD) is most accurate?

. The mechanical axis passes medial to the center of the knee, indicating a valgus deformity.
. The mechanical axis passes lateral to the center of the knee, indicating a varus deformity.
. The mechanical axis passes medial to the center of the knee, indicating a varus deformity.
. The mechanical axis passes lateral to the center of the knee, indicating a valgus deformity.
. The mechanical axis is perfectly aligned, suggesting the pain is not due to malalignment.

Correct Answer & Explanation

. The mechanical axis passes medial to the center of the knee, indicating a varus deformity.

Explanation

Correct Answer: CThe image displays a full-length standing anteroposterior radiograph of a lower extremity. The mechanical axis is defined as a line from the center of the femoral head to the center of the ankle joint. In this image, the mechanical axis clearly passes medial to the center of the knee joint. This medial deviation of the mechanical axis indicates a varus deformity, which places increased compressive loads on the medial compartment of the knee, leading to accelerated cartilage wear and pain, consistent with the patient's presentation. A valgus deformity would show the mechanical axis passing lateral to the center of the knee. Therefore, the statement that the mechanical axis passes medial to the center of the knee, indicating a varus deformity, is the most accurate description.

Question 1277

Topic: 8. Foot and Ankle

A 42-year-old female presents with a chief complaint of left knee pain and a 'knock-kneed' appearance. Clinical examination reveals the posture shown in the image below. Which of the following radiographic findings would most likely correlate with this clinical presentation?

. A mechanical lateral distal femoral angle (mLDFA) of 80 degrees.
. A medial proximal tibial angle (MPTA) of 95 degrees.
. A mechanical axis deviation (MAD) passing lateral to the center of the knee.
. An anatomical axis deviation (AAD) passing medial to the center of the knee.
. A joint line convergence angle (JLCA) indicating medial compartment narrowing.

Correct Answer & Explanation

. A mechanical axis deviation (MAD) passing lateral to the center of the knee.

Explanation

Correct Answer: CThe clinical image clearly demonstrates a valgus deformity (knock-kneed appearance), where the knees are closer together and the ankles are further apart. In a valgus deformity, the mechanical axis, which runs from the center of the femoral head to the center of the ankle, passes lateral to the center of the knee joint. This lateral deviation of the mechanical axis indicates increased load on the lateral compartment of the knee. Options A and B describe angular measurements: an mLDFA of 80 degrees would indicate a femoral varus (normal is 87° ± 3°), and an MPTA of 95 degrees would indicate a tibial valgus (normal is 87° ± 3°). While these angles can contribute to valgus, the most direct and overarching radiographic finding correlating with a clinical valgus deformity is the lateral deviation of the mechanical axis. Option D describes an anatomical axis deviation, which is less precise for overall limb alignment than the mechanical axis. Option E, medial compartment narrowing, is typically associated with varus deformity, not valgus.

Question 1278

Topic: 8. Foot and Ankle

A 28-year-old male presents with a chronic valgus deformity of his left knee following a childhood physeal injury. His Mechanical Axis Deviation (MAD) is measured at 15 mm lateral. The case highlights that the effect on MAD increases exponentially as the apex of the deformity approaches the knee joint. What is the primary biomechanical reason for the knee's particular vulnerability to malalignment?

. A. Its spherical ball-and-socket design limits its ability to accommodate altered positions.
. B. Its proximity to the subtalar joint allows for better tolerance of deformity.
. C. It functions largely as a hinge joint, making it highly susceptible to changes in coronal plane relationships.
. D. Its avascular nature makes it prone to rapid cartilage degeneration regardless of alignment.
. E. The presence of menisci makes it inherently unstable and prone to collapse under any eccentric load.

Correct Answer & Explanation

. C. It functions largely as a hinge joint, making it highly susceptible to changes in coronal plane relationships.

Explanation

Correct Answer: CThe case explicitly states, 'The hip, being a spherical ball-and-socket joint, is best able to accommodate an alteration in its normal position. The proximity of the subtalar joint allows the ankle to better tolerate deformity... However, the knee, functioning largely as a hinge, is the most vulnerable to changes in the normal coronal plane relationship.' A hinge joint has very limited ability to accommodate off-axis loading, leading to concentrated stress on one compartment.Incorrect Options:A. Its spherical ball-and-socket design limits its ability to accommodate altered positions:This describes the hip, which the text states isbest ableto accommodate alterations, not the knee.B. Its proximity to the subtalar joint allows for better tolerance of deformity:This describes the ankle, not the knee.D. Its avascular nature makes it prone to rapid cartilage degeneration regardless of alignment:While articular cartilage is avascular and prone to degeneration, the question asks about the knee'sparticular vulnerability to malalignment, which is its hinge-like function, not just the general nature of cartilage.E. The presence of menisci makes it inherently unstable and prone to collapse under any eccentric load:Menisci actually help distribute load and provide stability. While they can be damaged by eccentric load, their presence doesn't make the kneeinherentlyunstable in a way that explains its unique vulnerability to malalignment compared to other joints.

Question 1279

Topic: Ankle Trauma & Sports

When planning a proximal tibial osteotomy for a severe angular deformity, a fibular osteotomy is often required. At which level is the fibular osteotomy most safely and commonly performed to avoid peroneal nerve injury and distal tibiofibular syndesmotic disruption?

. Fibular neck
. Proximal third of the diaphysis
. Middle third of the diaphysis
. Distal metaphysis
. Through the lateral malleolus

Correct Answer & Explanation

. Middle third of the diaphysis

Explanation

A fibular osteotomy is safely performed in the middle third of the diaphysis. Proximal osteotomies risk injury to the common peroneal nerve, while distal osteotomies can disrupt the lateral collateral ligament complex or the distal tibiofibular syndesmosis.

Question 1280

Topic: 8. Foot and Ankle



A patient has a complex, double-level (multi-apical) varus deformity of the tibia. The surgeon decides to perform a single-level osteotomy at the diaphyseal CORA rather than addressing both CORAs. According to the principles of multi-apical deformity correction, what is the consequence of performing a single opening-wedge correction at one of the two CORAs?

. Perfect restoration of both the mechanical axis and joint orientation angles.
. The mechanical axis will be corrected, but the joint orientation angles will remain abnormal.
. The mechanical axis cannot be corrected without creating an opposing multi-apical deformity.
. Both the mechanical axis and the joint orientation lines will be exacerbated.
. The mechanical axis is corrected, but translation must occur in the sagittal plane.

Correct Answer & Explanation

. The mechanical axis will be corrected, but the joint orientation angles will remain abnormal.

Explanation

If a multi-apical deformity is treated with a single-level osteotomy, you can typically correct the mechanical axis deviation (so it passes through the center of the knee and ankle), but the joint orientation angles (e.g., MPTA, LDTA) will remain abnormal due to the uncorrected secondary CORA.

Test Yourself

Switch to an interactive, timed exam simulation to truly master this topic.

On this Page