Orthopedic Board Review MCQs: Foot, Trauma & Deformity

Question 1

A 45-year-old man presents with chronic lateral hindfoot pain and difficulty wearing shoes 18 months after non-operative management of a displaced intra-articular calcaneus fracture. Physical exam reveals a widened heel and restricted subtalar motion. What is the most likely cause of his lateral hindfoot pain?

Explanation

Malunion of a calcaneus fracture classically results in loss of calcaneal height, varus malalignment of the tuberosity, and increased heel width. The increased width is due to lateral blowout of the calcaneal wall, which frequently leads to subfibular impingement (abutment of the lateral calcaneal wall against the distal fibula), causing chronic lateral pain and peroneal tendon irritation.

Question 2

In a patient with Charcot-Marie-Tooth disease presenting with a classic cavovarus foot deformity, which of the following muscle imbalances is the primary driver for the plantarflexed first ray?

Explanation

The cavovarus foot deformity in Charcot-Marie-Tooth (CMT) disease is primarily driven by specific muscle imbalances. The peroneus longus overpowers the weakened tibialis anterior, driving the first metatarsal into plantarflexion and creating the forefoot-driven cavus. Additionally, the tibialis posterior overpowers the weakened peroneus brevis, contributing to the hindfoot varus.

Question 3

A 30-year-old sustains a Hawkins Type III talar neck fracture. Disruption of which of the following arteries places the talar body at the greatest risk for avascular necrosis?

Explanation

The artery of the tarsal canal (a branch of the posterior tibial artery) provides the majority of the blood supply to the talar body. While the talus also receives supply from the artery of the tarsal sinus and superior neck vessels, disruption of the artery of the tarsal canal significantly increases the risk of avascular necrosis, which is near 100% in Hawkins Type III fractures (talar neck fracture with subtalar and tibiotalar dislocation).

Question 4

A 22-year-old football player sustains a midfoot sprain. Radiographs reveal a subtle 'fleck sign' in the first intermetatarsal space. This radiographic finding represents a bony avulsion of the Lisfranc ligament from which of the following anatomical structures?

Explanation

The Lisfranc ligament is an interosseous ligament that runs from the lateral aspect of the medial cuneiform to the medial aspect of the base of the second metatarsal. The 'fleck sign' on an AP or mortise radiograph pathognomonically represents an avulsion fracture of this ligament, almost always detaching from the base of the second metatarsal.

Question 5

A 25-year-old professional basketball player sustains a fracture of the fifth metatarsal. Radiographs show a transverse fracture at the metaphyseal-diaphyseal junction extending into the fourth-fifth intermetatarsal articulation. What zone does this represent, and what is the optimal treatment for this athlete?

Explanation

This describes a Zone 2 fracture (a classic Jones fracture), which occurs at the metaphyseal-diaphyseal junction and involves the 4th-5th intermetatarsal facet. Due to the high risk of nonunion from a watershed blood supply and the high demands of a professional athlete, intramedullary screw fixation is the treatment of choice to optimize healing and allow for an earlier return to play.

Question 6

A 19-year-old female track athlete presents with insidious onset of dorsal midfoot pain. CT scan reveals a complete stress fracture of the navicular with no displacement. What is the recommended initial management?

Explanation

Navicular stress fractures typically occur in the relatively avascular central third of the bone. For non-displaced stress fractures, strict non-weight bearing in a short leg cast for 6 to 8 weeks is the gold standard initial treatment. Weight-bearing in a CAM boot leads to unacceptably high rates of nonunion. Displacement or failure of conservative management warrants ORIF.

Question 7

A 55-year-old woman presents with a painful, flexible flatfoot. On examination, she is unable to perform a single-leg heel rise. Radiographs demonstrate greater than 40% uncoverage of the talar head on the AP view. Which of the following surgical procedures is most appropriate to address her specific forefoot abduction deformity?

Explanation

The patient has Stage IIb adult-acquired flatfoot deformity (posterior tibial tendon dysfunction), characterized by a flexible deformity with significant forefoot abduction (evidenced by >40% talonavicular uncoverage). Lateral column lengthening (Evans osteotomy) is specifically indicated to correct the forefoot abduction by lengthening the lateral column.

Question 8

In evaluating an athlete with a hyperextension injury of the first metatarsophalangeal (MTP) joint (turf toe), which of the following is considered an absolute indication for surgical intervention?

Explanation

Turf toe represents a sprain or tear of the first MTP plantar plate complex. Absolute indications for operative intervention include a large intra-articular fracture, proximal migration of the sesamoids >3 mm (indicating complete disruption of the plantar plate/sesamoid complex), and a traumatic hallux valgus deformity.

Question 9

A 13-year-old boy presents with a rigid, painful flatfoot and a history of recurrent lateral ankle sprains. Lateral foot radiographs demonstrate an 'anteater nose' sign. Which of the following is the most likely diagnosis?

Explanation

The 'anteater nose' sign on a lateral foot radiograph is an anterior tubular elongation of the superior process of the calcaneus, which is pathognomonic for a calcaneonavicular coalition. In contrast, the 'C-sign' on a lateral radiograph is associated with a talocalcaneal coalition.

Question 10

A 40-year-old female undergoes evaluation for hallux valgus. Her radiographs show a hallux valgus angle (HVA) of 30 degrees, an intermetatarsal angle (IMA) of 14 degrees, and a Distal Metatarsal Articular Angle (DMAA) of 20 degrees with a congruent MTP joint. Which of the following procedures is necessary to correct the abnormal DMAA?

Explanation

A Distal Metatarsal Articular Angle (DMAA) >15 degrees indicates an abnormal lateral slope of the distal metatarsal articular surface. In the presence of a congruent joint and an abnormal DMAA, an extra-articular correction such as a Reverdin (distal medial closing wedge) osteotomy or a biplanar chevron is required to reorient the articular surface while maintaining joint congruency.

Question 11

A 60-year-old patient with poorly controlled diabetes mellitus presents with an acute, unilateral, erythematous, swollen, and warm foot. Pedal pulses are bounding. Radiographs of the foot show no fractures or joint subluxations. What is the most appropriate next step in management?

Explanation

This patient presents with Eichenholtz Stage 0 Charcot arthropathy (acute inflammation with normal radiographs). The most appropriate initial management is strict offloading and non-weight bearing total contact casting to arrest the process and prevent progression to fragmentation (Stage 1) and severe deformity. Bounding pulses reflect the autonomic neuropathy and arteriovenous shunting typical of Charcot.

Question 12

A 35-year-old man suffers a severe crush injury to the foot. Clinical exam is highly concerning for compartment syndrome. How many anatomically distinct osseofascial compartments are classically described in the foot?

Explanation

There are classically 9 osseofascial compartments in the foot: Medial, Lateral, Superficial, Calcaneal, four Interosseous compartments, and the Adductor compartment. Recognition of all 9 is necessary to ensure adequate surgical release (fasciotomy) in cases of foot compartment syndrome.

Question 13

When performing an arthrodesis of the first metatarsophalangeal (MTP) joint for severe hallux rigidus, what is the optimal position of fusion to ensure appropriate biomechanics during gait?

Explanation

The optimal position for a first MTP joint arthrodesis is 10-15 degrees of valgus and 10-15 degrees of dorsiflexion relative to the floor (or about 20-25 degrees relative to the first metatarsal axis). This position allows the hallux to clear the ground during the swing phase and provides a stable platform during toe-off without excessive pressure on the interphalangeal joint.

Question 14

A 24-year-old snowboarder sustains an ankle injury after landing hard from a jump. He has focal tenderness inferior to the lateral malleolus. Radiographs reveal a fracture of the lateral process of the talus. What is the most common mechanism for this specific injury?

Explanation

A fracture of the lateral process of the talus is famously known as 'snowboarder\'s fracture'. It classically occurs from a mechanism involving forced dorsiflexion and inversion of the ankle, often accompanied by an axial load. It is frequently misdiagnosed as an ankle sprain.

Question 15

A 14-year-old male sustains an ankle injury resulting in a juvenile Tillaux fracture. Which of the following ligaments is responsible for the avulsion of the anterolateral distal tibial epiphysis?

Explanation

A juvenile Tillaux fracture is an avulsion of the anterolateral distal tibial epiphysis. It occurs in adolescents because the distal tibial physis closes from medial to lateral. The open anterolateral physis remains vulnerable to avulsion by the anterior inferior tibiofibular ligament (AITFL) during an external rotation injury.

Question 16

The Achilles tendon is susceptible to rupture at its watershed area, located 2 to 6 cm proximal to its insertion on the calcaneus. The primary blood supply to this specific watershed region is derived from which of the following?

Explanation

The Achilles tendon lacks a true synovial sheath and is enveloped by a paratenon. The blood supply to its relatively hypovascular watershed region (2-6 cm proximal to the calcaneal insertion) is predominantly extrinsic, coming from vessels that traverse the paratenon, primarily branching from the posterior tibial artery.

Question 17

A 15-year-old female dancer presents with insidious onset of pain over the dorsal forefoot. Radiographs show flattening, sclerosis, and fragmentation of the second metatarsal head. What is the most likely diagnosis?

Explanation

Freiberg's infraction is avascular necrosis of the metatarsal head, most commonly affecting the second metatarsal. It frequently occurs in adolescent females and high-demand athletes (like dancers). Kohler's disease affects the navicular; Sever's is calcaneal apophysitis; Iselin's affects the 5th metatarsal base; Mueller-Weiss is spontaneous AVN of the adult navicular.

Question 18

A 68-year-old man presents with a 'slapping' gait and a mild foot drop. He notes a recent pop anteriorly at the ankle while walking downstairs. Examination reveals a palpable mass over the anterior ankle and inability to actively dorsiflex the ankle past neutral, although toe extension is preserved. What is the classic 'triad' associated with this diagnosis?

Explanation

This patient has a spontaneous rupture of the tibialis anterior tendon. The classic triad of a tibialis anterior tendon rupture includes: 1) a soft tissue mass (pseudotumor) at the anterior ankle representing the retracted tendon stump, 2) loss of active ankle dorsiflexion, and 3) a steppage gait (foot drop). EHL overactivity may be a compensatory sign, but the accepted classic triad includes the steppage gait.

Question 19

During an extensile lateral approach for open reduction internal fixation of a calcaneus fracture, full-thickness subperiosteal flaps are raised. Which structure is at greatest risk of iatrogenic injury when developing the superior-vertical limb of the incision?

Explanation

The sural nerve is at the greatest risk of injury during the extensile lateral approach to the calcaneus. It courses closely to both the vertical (superior) limb and the horizontal (inferior) limb of the incision. Injury can result in painful neuromas or lateral foot numbness. Retracting the full-thickness flap with 'no-touch' techniques utilizing K-wires in the talus/fibula minimizes this risk.

Question 20

A 16-year-old female presents with medial midfoot pain exacerbated by shoe wear. Radiographs demonstrate an ossicle located medial to the navicular body, separated by a synchondrosis. If conservative management fails, surgical excision of the ossicle usually requires detachment and reattachment of which of the following tendons?

Explanation

The patient has a symptomatic accessory navicular (Type II). The tibialis posterior tendon commonly inserts, at least partially, into the accessory ossicle. Excision of the ossicle (the Kidner procedure) frequently requires advancing and reattaching the tibialis posterior tendon to the remaining native navicular to restore medial longitudinal arch dynamic support.

Question 21

A 24-year-old snowboarder presents with lateral ankle pain after a hard landing. Radiographs show a fracture of the lateral process of the talus. CT imaging confirms it involves the subtalar joint and is displaced 3 mm with a 1.5 cm primary fragment. What is the most appropriate management?

Explanation

Lateral process of the talus fractures ('snowboarder's fractures') with >2 mm of displacement or significant joint involvement (>1 cm fragment) are typically treated with ORIF to restore subtalar congruity and prevent post-traumatic arthritis. Comminuted, unfixable fragments may be treated with primary excision, but large displaced fragments warrant internal fixation.

Question 22

A 14-year-old boy presents with a rigid flatfoot and recurrent lateral ankle sprains. Radiographs reveal a continuous 'C-sign' on the lateral view. What is the most likely diagnosis, and which anatomical structure is most commonly used for interposition following resection?

Explanation

The continuous 'C-sign' on a lateral foot radiograph is highly specific for a talocalcaneal coalition (typically involving the middle facet). Operative resection is indicated for symptomatic cases failing conservative care. Interposition with a fat graft or the flexor hallucis longus (FHL) tendon is commonly performed to prevent recurrence. The extensor digitorum brevis (EDB) is typically used as an interposition graft for calcaneonavicular coalitions, which are best seen on the 45-degree oblique view.

Question 23

A 28-year-old man with Charcot-Marie-Tooth disease presents with a progressive, symptomatic bilateral cavovarus foot deformity. A Coleman block test is performed. The hindfoot corrects to a neutral alignment when the plantarflexed first metatarsal is allowed to hang off the medial edge of the block. What does this indicate, and what hindfoot-specific bony procedure is indicated?

Explanation

The Coleman block test differentiates between a forefoot-driven (flexible) hindfoot varus and a rigid hindfoot varus. If the hindfoot corrects to neutral when the plantarflexed first ray drops off the block, the varus is forefoot-driven (the rigidly plantarflexed 1st ray is forcing the hindfoot into varus). In this scenario, the hindfoot is flexible, and addressing the forefoot (e.g., dorsiflexion osteotomy of the 1st metatarsal) is sufficient without the need for a structural calcaneal osteotomy.

Question 24

A 22-year-old collegiate track athlete complains of vague dorsal midfoot pain that worsens with sprinting. Radiographs are negative. MRI reveals a stress fracture of the navicular involving the central third, and a subsequent CT scan shows an incomplete fracture line extending halfway across the bone. What represents the most reliable initial nonoperative treatment that minimizes nonunion risk?

Explanation

High-risk stress fractures of the navicular occur in the central third due to a relative watershed vascular area. For incomplete, non-displaced navicular stress fractures, the gold standard nonoperative treatment is strict non-weight-bearing in a short leg cast for 6-8 weeks. Weight-bearing casts or removable boots lead to unacceptably high rates of delayed union or nonunion.

Question 25

An extensile lateral approach is planned for a displaced intra-articular calcaneus fracture (Sanders Type III). Which of the following technical considerations is most critical to minimize the risk of wound-healing complications and flap necrosis?

Explanation

Wound complications are common (up to 25%) with the extensile lateral approach to the calcaneus. A full-thickness subperiosteal flap must be raised in a single plane (without undermining the subcutaneous tissue) to preserve the delicate blood supply from the lateral calcaneal artery. The 'no-touch' retraction technique using K-wires placed into the talus, cuboid, and fibula avoids the focal pressure necrosis caused by self-retaining or hand-held retractors.

Question 26

A 55-year-old woman presents with a flexible flatfoot deformity, marked weakness with manual muscle testing of inversion in plantarflexion, and inability to perform a single-limb heel rise test. The deformity is fully correctable passively. According to the Johnson and Strom classification, what stage of Posterior Tibial Tendon Dysfunction (PTTD) does this represent, and what is the standard surgical treatment if conservative measures fail?

Explanation

Stage II PTTD is characterized by a flexible flatfoot deformity, inability to perform a single-limb heel rise, and PTT weakness/dysfunction. Treatment typically involves a soft tissue procedure (FDL transfer to reconstruct the PTT) combined with a bony procedure to correct the deformity and protect the transfer (e.g., medial displacement calcaneal osteotomy, lateral column lengthening). Stage I involves pain and tenosynovitis without deformity. Stage III is a rigid deformity requiring arthrodesis.

Question 27

A 21-year-old elite football player sustains a fracture of the fifth metatarsal. Radiographs show a fracture line located at the metaphyseal-diaphyseal junction, extending into the fourth-fifth intermetatarsal articulation. What is the diagnosis and the most appropriate treatment to ensure early return to play?

Explanation

A fracture at the metaphyseal-diaphyseal junction involving the 4th-5th intermetatarsal articulation is a Zone 2 (Jones) fracture. Due to the vascular watershed area, it is at higher risk of delayed union or nonunion. In elite athletes, early intramedullary screw fixation is the standard of care to maximize union rates and minimize time to return to play compared to conservative management.

Question 28

A professional running back sustains an acute hyperextension injury to his first metatarsophalangeal (MTP) joint. Clinical examination reveals gross instability of the MTP joint on Lachman testing. MRI confirms a complete tear of the plantar plate from the metatarsal neck with proximal retraction of the sesamoids. What is the most appropriate management?

Explanation

This describes a Grade 3 Turf Toe injury (complete disruption of the plantar plate/capsuloligamentous complex). Given the gross instability, proximal retraction of the sesamoids, and the patient's status as a professional athlete requiring push-off strength, surgical repair of the plantar plate is indicated to restore MTP joint stability. Grades 1 and 2 are typically managed non-operatively.

Question 29

A 30-year-old male sustains a severe crush injury to his foot. Clinical signs raise high suspicion for an acute compartment syndrome. How many distinct fascial compartments are classically described in the foot, and which surgical approach is standardly recommended to release them?

Explanation

There are classically 9 distinct fascial compartments in the foot: medial, lateral, superficial, calcaneal, four interosseous, and adductor. The standard surgical release utilizes a dual dorsal approach (incisions slightly medial to the 2nd metatarsal and lateral to the 4th metatarsal) combined with a medial approach (along the inferior border of the first metatarsal) to adequately access and release all 9 compartments.

Question 30

A 45-year-old female presents for surgical correction of symptomatic hallux valgus. Radiographs demonstrate a Hallux Valgus Angle (HVA) of 32 degrees, an Intermetatarsal Angle (IMA) of 13 degrees, and a Distal Metatarsal Articular Angle (DMAA) of 20 degrees. The first MTP joint is congruous. Which of the following procedures is best suited to address this specific combination of radiographic findings?

Explanation

The patient has an abnormally high DMAA (>10-15 degrees is considered abnormal). If the DMAA is high and the joint is congruous, a standard proximal or diaphyseal osteotomy alone will tilt the articular surface further into valgus, leading to incongruity and rapid recurrence. A distal biplanar osteotomy (like a Reverdin) or a modified chevron that includes a medial closing wedge is required to correct the articular orientation (DMAA).

Question 31

A 42-year-old recreational athlete suffers an acute, closed midsubstance Achilles tendon rupture. Based on current high-level evidence, which of the following is true regarding outcomes when functional rehabilitation (early weight-bearing and mobilization) is employed in non-operative management compared to operative management?

Explanation

Multiple randomized controlled trials have demonstrated that when acute Achilles tendon ruptures are treated non-operatively using a functional rehabilitation protocol (early weight-bearing and early ROM), the rerupture rate is equivalent to operative management. Non-operative management avoids surgical complications, such as deep infection and wound healing issues, giving it a lower overall complication profile.

Question 32

A 28-year-old male sustains a Hawkins Type III fracture of the talar neck. What does this fracture pattern involve, and what is the approximate historical rate of avascular necrosis (AVN) of the talar body associated with it?

Explanation

Hawkins Type III is a vertical fracture of the talar neck with dislocation of both the subtalar and tibiotalar (ankle) joints. Because the major blood supply to the talar body is severely disrupted, the rate of AVN is historically reported as nearly 80-100%.

Question 33

A 34-year-old male sustains a pronation-external rotation ankle fracture. After rigid fixation of the malleoli, the Cotton test is positive. Fixation is performed using a suture-button construct. According to biomechanical and clinical studies, what is the primary advantage of dynamic suture-button fixation over rigid static syndesmotic screw fixation?

Explanation

Suture-button constructs for syndesmotic fixation provide dynamic stabilization, allowing physiologic micromotion of the fibula relative to the tibia. Clinical advantages include avoidance of routine hardware removal (as is often needed or happens via breakage with rigid screws) while maintaining similar or slightly superior clinical outcomes.

Question 34

A 25-year-old equestrian presents with midfoot pain after her foot was caught in the stirrup. Weight-bearing radiographs show a 3 mm diastasis between the base of the 1st and 2nd metatarsals. An MRI confirms a complete tear of the Lisfranc ligament without any associated fractures. Which of the following is the most appropriate definitive management for this purely ligamentous Lisfranc injury?

Explanation

High-level evidence (Ly and Coetzee, JBJS 2006) supports primary arthrodesis for purely ligamentous Lisfranc injuries, as it yields superior functional outcomes and lower reoperation rates compared to ORIF. Ligamentous injuries heal poorly and often lead to late midfoot collapse or post-traumatic arthritis when treated with ORIF alone.

Question 35

A 14-year-old girl sustains an ankle injury while playing soccer. Radiographs reveal a Salter-Harris III fracture of the anterolateral distal tibia. Which of the following best describes the anatomical basis and mechanism of this specific fracture pattern?

Explanation

A juvenile Tillaux fracture is a Salter-Harris III fracture of the anterolateral distal tibia. It occurs in adolescents due to the asymmetric closure of the distal tibial physis (closes central -> medial -> lateral). An external rotation force causes the anterior inferior tibiofibular ligament (AITFL) to avulse the anterolateral epiphysis, which is the last portion of the physis to close.

Question 36

In the surgical management of a rigid cavovarus foot deformity secondary to Charcot-Marie-Tooth disease, a Dwyer osteotomy is frequently utilized. Which of the following accurately describes this procedure?

Explanation

The Dwyer osteotomy is a lateral closing-wedge osteotomy of the calcaneus. It is used to correct the rigid hindfoot varus deformity commonly seen in cavovarus feet. Removing a laterally based wedge allows the calcaneal tuberosity to translate and angulate into valgus.

Question 37

A 45-year-old marathon runner complains of chronic, severe heel pain that has failed 6 months of conservative management for plantar fasciitis. Pain is maximal at the medial calcaneal tuberosity and radiates distally. At surgery, release of the first branch of the lateral plantar nerve (Baxter's nerve) is planned. Between which two muscles is this nerve typically entrapped?

Explanation

Baxter's nerve (the first branch of the lateral plantar nerve) provides motor innervation to the abductor digiti minimi. It typically becomes entrapped as it passes under the deep fascia of the abductor hallucis and travels between the deep surface of the abductor hallucis muscle and the medial surface of the quadratus plantae muscle.

Question 38

The high rate of delayed union and nonunion in Jones fractures (Zone 2 of the proximal fifth metatarsal) is primarily attributed to its unique vascular supply. Which of the following describes the vascular pattern that creates this watershed area?

Explanation

The proximal fifth metatarsal has a distinct vascular anatomy. The tuberosity and metaphysis (Zone 1) are well-supplied by metaphyseal arteries. The diaphysis is supplied by a nutrient artery that enters the medial cortex and sends a retrograde branch proximally. Zone 2 (the metaphyseal-diaphyseal junction) represents a vascular 'watershed' area between these two distinct blood supplies, rendering it prone to poor healing.

Question 39

A 24-year-old female presents with a snapping sensation over the lateral aspect of her ankle during dorsiflexion and eversion. Examination reveals subluxation of the peroneal tendons over the lateral malleolus. During surgical repair, an osseous procedure is deemed necessary to deepen a flat retromalleolar groove. What is the most appropriate osseous procedure to achieve this while preserving the gliding mechanism?

Explanation

Deepening the retromalleolar groove can be achieved by elevating a cortical 'trapdoor' or osteoperiosteal flap from the posterior aspect of the distal fibula, excavating the underlying cancellous bone, and tamping the cortical flap back down. This preserves the smooth fibrocartilaginous gliding surface for the tendons while effectively deepening the groove to prevent subluxation.

Question 40

A 60-year-old male with end-stage post-traumatic ankle osteoarthritis is undergoing an isolated ankle arthrodesis. To optimize gait kinematics and limit adjacent joint degeneration, what is the ideal position for fusing the tibiotalar joint?

Explanation

The optimal position for ankle arthrodesis is neutral dorsiflexion (0 degrees), 0 to 5 degrees of hindfoot valgus, and external rotation equal to the contralateral side (typically 5 to 10 degrees). Plantarflexion causes a recurvatum thrust at the knee, dorsiflexion causes a peg-leg gait, and varus leads to rigid locking of the transverse tarsal joints and overload of the lateral border of the foot.

Question 41

A 24-year-old snowboarder presents with lateral ankle pain after a hard landing. Radiographs show a small bony fragment inferior to the lateral malleolus. CT confirms a highly comminuted fracture of the lateral process of the talus involving the subtalar joint. Which of the following is the most appropriate management for a severely displaced, comminuted lateral process fracture that cannot be adequately reconstructed?

Explanation

Fractures of the lateral process of the talus (Snowboarder's fractures) often involve the subtalar joint. While large, non-comminuted fragments (>1 cm) are best treated with open reduction and internal fixation (ORIF), severely comminuted and displaced fragments that cannot be anatomically reconstructed should be excised to prevent post-traumatic subtalar arthritis and impingement.

Question 42

A 35-year-old male sustains an ankle fracture-dislocation. Closed reduction in the emergency department is unsuccessful. Radiographs show a bimalleolar equivalent fracture with the fibula displaced posterior to the incisura fibularis of the tibia. What is the most likely anatomic structure preventing closed reduction?

Explanation

This describes a Bosworth fracture-dislocation, a rare injury where the proximal fibular fragment becomes entrapped behind the posterior tibial tubercle. The intact posterior tibiofibular ligament (PTFL) tethers the fibula, making closed reduction virtually impossible and necessitating open reduction.

Question 43

A 15-year-old boy presents with progressive bilateral foot deformities. On examination, he has a high medial arch, plantarflexed first ray, and hindfoot varus. A Coleman block test is performed, and the hindfoot varus corrects to neutral. Which of the following tendon transfers is most appropriate to address the muscular imbalance driving this specific flexible hindfoot and rigid forefoot deformity?

Explanation

The Coleman block test correcting the hindfoot varus indicates a forefoot-driven deformity (due to a rigid plantarflexed first ray). In Charcot-Marie-Tooth (CMT) disease, the peroneus longus is typically overactive relative to the weak anterior tibialis, driving the first ray down. Transferring the peroneus longus to the peroneus brevis removes the deforming plantarflexion force on the first ray and augments hindfoot eversion.

Question 44

A 20-year-old collegiate track athlete presents with insidious onset vague midfoot pain. MRI confirms a stress fracture in the central third of the tarsal navicular. The vulnerability of this area to fracture is primarily due to a watershed area of blood supply. Which arteries supply the medial and lateral poles of the navicular, creating this central avascular zone?

Explanation

The blood supply to the tarsal navicular enters via branches from the dorsalis pedis artery (dorsal) and the medial plantar artery (plantar). These vessels supply the medial and lateral poles, leaving the central third as a watershed area highly susceptible to stress fractures and nonunion.

Question 45

In Stage II adult acquired flatfoot deformity (posterior tibial tendon dysfunction), the spring ligament is frequently attenuated or torn. Which of the following is the most important static stabilizer of the talonavicular joint and the strongest component of the spring ligament complex?

Explanation

The spring ligament complex consists of three main components. The superomedial calcaneonavicular ligament is the strongest and most critical static restraint to plantar and medial subluxation of the talar head in flatfoot deformity.

Question 46

A 45-year-old diabetic male undergoes a Chopart (midtarsal) amputation for necrotizing fasciitis of the forefoot. Which of the following deformities is most likely to develop postoperatively if prophylactic tendon balancing is not performed?

Explanation

A Chopart amputation removes the distal insertions of the primary dorsiflexors (anterior tibialis, EHL, EDL) and evertors (peroneus longus and brevis). This leaves the strong plantarflexors (Achilles) and invertors (posterior tibialis) unopposed, reliably leading to a severe equinovarus deformity unless appropriate tendon transfers (e.g., anterior tibialis to the talar neck) and Achilles lengthening are performed.

Question 47

A 22-year-old football player sustains a hyperextension injury to his first metatarsophalangeal (MTP) joint. Clinical examination reveals ecchymosis, moderate swelling, and unrestricted but painful active range of motion. MRI shows a partial tear of the plantar plate with intact articular cartilage. What is the most appropriate initial management for this Grade 2 Turf Toe injury?

Explanation

A Grade 2 turf toe injury represents a partial tear of the plantar plate complex. Standard management involves protection and immobilization (often in a walking boot) for 1 to 4 weeks to allow for initial healing, followed by progressive weight-bearing and return to play with a stiff-soled shoe or taping. Grade 1 injuries can often return immediately with taping, while Grade 3 (complete tear) may require operative intervention in elite athletes.

Question 48

During the operative fixation of an intra-articular calcaneus fracture via an extensile lateral approach, the surgeon places a 'constant' screw from the lateral cortex directing medially to secure the tuberosity to the anteromedial (sustentacular) fragment. Which anatomical structure is tightly adherent to the inferior surface of the sustentaculum tali, serving as an important landmark but also at risk of injury from an overly long drill bit or screw?

Explanation

The flexor hallucis longus (FHL) tendon courses directly inferior to the sustentaculum tali in its own fibro-osseous groove. It is at high risk of iatrogenic injury or tethering if a drill or screw inadvertently penetrates the inferior or medial aspect of the sustentaculum tali during calcaneus fracture fixation.

Question 49

A 30-year-old male sustains an external rotation injury to his ankle. Radiographs and intraoperative fluoroscopy reveal a syndesmotic disruption without a fibular fracture (purely ligamentous injury). Which of the following ligaments is typically the first to rupture in the sequence of a syndesmotic injury?

Explanation

In external rotation syndesmotic injuries, the classical sequence of ligamentous failure begins anteriorly with the anterior inferior tibiofibular ligament (AITFL), propagates to the interosseous ligament (IOL), and finally involves the posterior inferior tibiofibular ligament (PITFL) or results in a posterior malleolus avulsion.

Question 50

A 42-year-old recreational athlete sustains an acute Achilles tendon rupture. The treating physician is deciding between non-operative and operative management using ultrasound guidance. Which of the following findings is widely accepted as an indication to favor surgical repair over non-operative treatment?

Explanation

Non-operative management of acute Achilles tendon ruptures yields excellent results provided the tendon ends can appose in equinus. An ultrasound demonstrating a gap > 5 mm with the ankle resting in 20 degrees of plantarflexion suggests insufficient apposition for functional healing, making it a strong relative indication for surgical repair.

Question 51

A 38-year-old male sustains a high-energy OTA/AO type 43-C3 pilon fracture. The surgeon plans a dual-incision approach. To minimize wound necrosis, the incisions should be based on distinct vascular angiosomes. While the anterolateral incision is based on the anterior tibial artery, what artery supplies the primary angiosome utilized for the standard posterolateral incision?

Explanation

The standard posterolateral approach to the distal tibia and fibula uses an angiosome primarily supplied by the peroneal artery. The anterolateral approach uses the anterior tibial artery angiosome. Utilizing separate angiosomes and maintaining at least a 7 cm skin bridge minimizes the risk of devastating wound complications.

Question 52

A 21-year-old elite collegiate basketball player complains of lateral foot pain after a cutting maneuver. Radiographs show a transverse fracture at the metaphyseal-diaphyseal junction of the fifth metatarsal, extending into the fourth-fifth intermetatarsal articulation. What is the most appropriate management for this specific patient profile?

Explanation

This is a Jones fracture (Zone 2 of the base of the 5th metatarsal). Because it occurs in a vascular watershed area, it carries a high risk of nonunion. In elite or highly competitive athletes, early operative intervention with an intramedullary screw is the standard of care to maximize union rates and minimize time away from play.

Question 53

A 35-year-old equestrian falls from a horse, sustaining an axial load with forceful abduction of the forefoot. Radiographs demonstrate a comminuted fracture of the cuboid with lateral column shortening. Which of the following is considered an absolute indication for operative fixation of a cuboid fracture?

Explanation

Nutcracker fractures of the cuboid involve crushing the cuboid between the calcaneus and the 4th/5th metatarsals. Absolute indications for surgery to prevent disabling planovalgus deformity and late midfoot arthritis include lateral column shortening > 3 mm (some sources cite > 2 mm) or articular displacement > 1-2 mm.

Question 54

A 14-year-old boy presents with an ankle injury after falling off his skateboard. Radiographs demonstrate a Salter-Harris III fracture of the anterolateral distal tibia. What is the primary deforming force and the associated ligament responsible for avulsing this fragment?

Explanation

A juvenile Tillaux fracture is a Salter-Harris III fracture of the anterolateral distal tibial epiphysis. It is caused by an external rotation force applied to the foot. The anterior inferior tibiofibular ligament (AITFL) is tensioned and avulses the anterolateral fragment, as this is the final portion of the distal tibial physis to close.

Question 55

A 55-year-old female presents with symptomatic hallux valgus. Radiographs reveal a Hallux Valgus Angle (HVA) of 35 degrees, an Intermetatarsal Angle (IMA) of 13 degrees, and a Distal Metatarsal Articular Angle (DMAA) of 22 degrees (normal < 10 degrees). The MTP joint is congruous. Which of the following procedures is most appropriate to correct her deformity while minimizing the risk of recurrence?

Explanation

This patient has moderate hallux valgus with a significantly elevated DMAA and a congruous MTP joint. Correcting the IMA alone without addressing the abnormal DMAA will create an incongruous joint and inevitably lead to early recurrence. A distal biplanar osteotomy (such as a Reverdin-Green or modified biplanar Chevron) is required to translate the metatarsal head laterally while simultaneously rotating the articular surface to correct the DMAA.

Question 56

A 28-year-old male suffers a severe crush injury to his right foot. Intracompartmental pressures are measured, and a diagnosis of foot compartment syndrome is made. A double dorsal incision approach is planned for fasciotomy. Which compartments are accessed through the medial dorsal incision?

Explanation

The foot contains 9 compartments. In a double dorsal incision fasciotomy, the medial incision (placed medial to the 2nd metatarsal) provides access to the medial compartment and the 1st and 2nd interosseous compartments. The lateral incision (lateral to the 4th metatarsal) accesses the lateral, central, and 3rd/4th interosseous compartments. The calcaneal compartment is typically accessed medially.

Question 57

A 45-year-old construction worker falls from a height of 6 feet, sustaining an acute, purely ligamentous Lisfranc injury with lateral subluxation of the 1st through 3rd tarsometatarsal joints. Which of the following statements regarding primary arthrodesis compared to Open Reduction Internal Fixation (ORIF) for this specific injury pattern is supported by current Level I evidence?

Explanation

Multiple RCTs (e.g., Ly and Coetzee, 2006) demonstrate that for purely ligamentous Lisfranc injuries, primary arthrodesis results in similar or superior long-term functional outcomes but with a significantly lower rate of planned secondary surgeries. ORIF frequently requires hardware removal or late conversion to arthrodesis due to post-traumatic arthritis.

Question 58

A 32-year-old male sustains a Hawkins Type III talar neck fracture following a motor vehicle collision. Which of the following describes the correct positioning to obtain a Canale view radiograph to optimally assess the talar neck alignment?

Explanation

The Canale view is essential for visualizing varus/valgus alignment of the talar neck. It is properly obtained by placing the ankle in maximum equinus (plantarflexion), pronating the foot approximately 15 degrees, and directing the x-ray beam 75 degrees cephalad from the horizontal.

Question 59

A 65-year-old male with chronic Achilles tendinopathy presents with an acute on chronic rupture leaving a 6 cm defect. The surgeon elects to perform a local tendon transfer. Which of the following best describes the biomechanical rationale for choosing the Flexor Hallucis Longus (FHL) over the Flexor Digitorum Longus (FDL) for this transfer?

Explanation

Both the FHL and FDL are in-phase synergists with the Achilles tendon. The FHL is the preferred transfer because it is approximately twice as strong as the FDL, has a highly vascularized muscle belly that aids in healing, and its axis of pull (directly posterior to the ankle joint) more closely replicates that of the Achilles.

Question 60

A 40-year-old male presents with chronic, functionally limiting ankle pain. Weight-bearing radiographs demonstrate asymmetric medial joint space narrowing of the tibiotalar joint with a varus tibial anterior surface (TAS) angle of 82 degrees. The lateral joint space is completely preserved, and he has a flexible hindfoot. What is the most appropriate surgical indication for a supramalleolar osteotomy (SMO) in this patient?

Explanation

Supramalleolar osteotomy (SMO) is a joint-preserving procedure indicated for young, active patients with asymmetric (typically medial) ankle arthritis driven by an extra-articular distal tibial deformity (like varus). By correcting the mechanical axis, load is transferred to the preserved lateral cartilage, alleviating pain and delaying the need for arthroplasty or arthrodesis.

Question 61

During a precise open reduction and internal fixation of a subtle midfoot injury, the surgeon must restore the critical stabilizing structure of the Lisfranc complex. The primary Lisfranc ligament anatomically connects which of the following osseous structures?

Explanation

The Lisfranc ligament is a robust interosseous ligament that connects the lateral surface of the medial cuneiform to the medial base of the second metatarsal. It is critical for the stability of the tarsometatarsal articulation and midfoot arch.

Question 62

A 60-year-old woman presents with a painful, severe flatfoot deformity. Physical examination reveals an inability to perform a single-leg heel rise, and the hindfoot valgus deformity cannot be passively corrected to neutral. What is the most appropriate surgical management for this stage of disease?

Explanation

The patient has a rigid, non-correctable hindfoot valgus, diagnostic of Stage III adult acquired flatfoot deformity. A triple arthrodesis (fusion of the subtalar, talonavicular, and calcaneocuboid joints) is required to correct rigid multi-planar deformities.

Question 63

A 40-year-old woman presents with a painful bunion. Weight-bearing radiographs reveal a hallux valgus angle of 45 degrees and an intermetatarsal angle (IMA) of 18 degrees. Clinical examination demonstrates notable hypermobility at the first tarsometatarsal (TMT) joint. Which of the following procedures is most strongly indicated?

Explanation

The Lapidus procedure (first TMT arthrodesis) is ideal for correcting a large intermetatarsal angle, especially in the presence of first ray hypermobility. It definitively addresses the apex of the deformity while stabilizing the medial column.

Question 64

A 21-year-old elite track athlete develops insidious onset dorsal midfoot pain. A CT scan confirms a dorsal cortical radiolucency in the central third of the navicular. Which underlying anatomic factor predominantly predisposes this specific region to poor healing and nonunion?

Explanation

Navicular stress fractures typically occur in the central third of the bone. This region represents an avascular watershed area between the branches of the dorsalis pedis and medial plantar arteries, predisposing it to delayed union or nonunion.

Question 65

A patient with post-traumatic end-stage ankle arthritis is undergoing an ankle arthrodesis. To maximize gait efficiency and limit the development of degenerative changes in adjacent hindfoot joints, what is the optimal position for the arthrodesis?

Explanation

The optimal position for ankle arthrodesis is neutral dorsiflexion, 0 to 5 degrees of hindfoot valgus, and 5 to 10 degrees of external rotation. This specific alignment mimics a functional plantigrade foot and prevents excessive compensatory stress on the transverse tarsal joints.

Question 66

In a lateral subtalar dislocation, the injury is often irreducible by closed means. Which of the following structures most commonly blocks the closed reduction of a lateral subtalar dislocation?

Explanation

Lateral subtalar dislocations are commonly irreducible due to the interposition of the posterior tibial tendon around the talar neck. In contrast, medial subtalar dislocations are typically blocked by the extensor digitorum brevis, extensor retinaculum, or the talonavicular joint capsule.

Question 67

Which of the following descriptions accurately characterizes the anatomical origin and insertion of the Lisfranc ligament?

Explanation

The Lisfranc ligament is the largest and strongest interosseous ligament of the midfoot. It originates from the lateral, plantar surface of the medial cuneiform and inserts on the medial aspect of the base of the second metatarsal.

Question 68

A 55-year-old female presents with Stage IIb posterior tibial tendon dysfunction. Clinical exam shows a flexible hindfoot valgus and significant forefoot abduction with greater than 30% uncoverage of the talonavicular joint. In addition to a flexor digitorum longus transfer and a medial displacement calcaneal osteotomy, which additional procedure is most appropriate?

Explanation

Stage IIb posterior tibial tendon dysfunction is characterized by significant forefoot abduction (>30% talonavicular uncoverage). A lateral column lengthening (such as an Evans osteotomy) is required to restore the lateral column length and correct the forefoot abduction.

Question 69

Navicular stress fractures carry a high risk of delayed union and nonunion. This risk is primarily attributed to an avascular watershed zone located in which region of the navicular bone?

Explanation

The central third of the navicular is an avascular watershed zone because it receives limited collateral blood supply from the dorsalis pedis and medial plantar arteries, which predominantly supply the periphery.

Question 70

A 13-year-old boy presents with a rigid, painless flatfoot and a history of frequent ankle sprains. Lateral radiographs demonstrate an elongated anterior process of the calcaneus, known as the 'anteater nose sign.' Which of the following is the most appropriate initial surgical management if conservative therapy fails?

Explanation

The 'anteater nose sign' is pathognomonic for a calcaneonavicular coalition. When conservative treatment fails in a young patient without arthritic changes, resection of the coalition with interposition of the extensor digitorum brevis is the standard of care.

Question 71

A 40-year-old marathon runner with chronic heel pain continues to have symptoms despite 6 months of stretching and orthotics. The pain is maximal over the medial heel and is associated with weakness in active abduction of the fifth toe. Entrapment of which of the following nerves is the most likely diagnosis?

Explanation

Baxter's nerve is the first branch of the lateral plantar nerve. Entrapment mimics plantar fasciitis but often presents with chronic medial heel pain and motor weakness of the abductor digiti minimi.

Question 72

A patient is evaluated 8 weeks after closed reduction and percutaneous pinning of a non-displaced talar neck fracture. An AP radiograph of the ankle reveals a subchondral radiolucent band in the dome of the talus (Hawkins sign). What does this radiographic finding indicate?

Explanation

The Hawkins sign is a subchondral radiolucent band representing disuse osteopenia. It confirms that the talar body has an intact vascular supply capable of generating a hyperemic resorptive response, thus virtually ruling out avascular necrosis.

Question 73

In displaced intra-articular calcaneus fractures, the sustentacular (anteromedial) fragment remains relatively constant in its anatomic position relative to the talus. Which ligamentous attachment is primarily responsible for preventing the displacement of this fragment?

Explanation

The sustentaculum tali fragment remains in a constant anatomical position because it is firmly tethered to the talus by the strong interosseous talocalcaneal ligament and the deltoid ligament.

Question 74

A 60-year-old female presents with a painful bunion. Weight-bearing radiographs reveal a Hallux Valgus Angle (HVA) of 45 degrees, an Intermetatarsal Angle (IMA) of 18 degrees, and clinical hypermobility of the first tarsometatarsal (TMT) joint. Which of the following surgical procedures is most appropriate?

Explanation

For severe hallux valgus (IMA > 15 degrees, HVA > 40 degrees) accompanied by first TMT hypermobility, a Lapidus procedure (first TMT arthrodesis) provides powerful, stable correction and addresses the underlying hypermobility.

Question 75

A patient develops a compartment syndrome of the foot following a severe crush injury. There are a total of 9 compartments in the foot. Which of the following muscles is uniquely located within the calcaneal compartment?

Explanation

The calcaneal compartment is a distinct deep compartment in the hindfoot that primarily contains the quadratus plantae muscle, as well as the lateral plantar nerve and vessels.

Question 76

A professional football player sustains a severe hyperdorsiflexion injury to the first metatarsophalangeal joint. MRI demonstrates a complete disruption of the plantar plate with proximal retraction of the sesamoids. What is the recommended treatment for this Grade 3 turf toe injury?

Explanation

A Grade 3 turf toe involves a complete tear of the plantar plate complex with proximal retraction of the sesamoids. In competitive athletes, primary surgical repair is indicated to restore joint stability and push-off strength.

Question 77

A patient with diabetes and a plantar midfoot ulcer presents with significant midfoot swelling and erythema. Plain radiographs show diffuse midfoot bone destruction. Which imaging modality has the highest specificity for differentiating acute Charcot neuroarthropathy from superimposed osteomyelitis?

Explanation

Differentiating Charcot neuroarthropathy from osteomyelitis can be challenging on MRI due to reactive marrow edema. The combination of an Indium-111 leukocyte scan and a Tc-99m sulfur colloid marrow scan provides the highest specificity for diagnosing osteomyelitis in this setting.

Orthopedic Surgery Board Review MCQs: Arthroplasty, Trauma & Spine Part 255

Orthopedic Surgery Board Review MCQs: Foot, Trauma & Deformity | Part 25

Key Takeaway

Orthopedic Surgery Board Review MCQs: Foot, Trauma & Deformity | Part 25

Chapter Index