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Question 2261

Topic: Ankle Trauma & Sports

A 50-year-old male sustains a severe pilon fracture. The preoperative CT scan demonstrates a large, displaced anterolateral distal tibial articular fragment (the Tillaux-Chaput fragment). Which of the following ligaments remains attached to this fragment and often dictates its displacement?

. Anterior inferior tibiofibular ligament (AITFL)
. Posterior inferior tibiofibular ligament (PITFL)
. Anterior talofibular ligament (ATFL)
. Calcaneofibular ligament (CFL)
. Deltoid ligament

Correct Answer & Explanation

. Anterior inferior tibiofibular ligament (AITFL)


Explanation

The Tillaux-Chaput fragment is the anterolateral articular fragment of the distal tibia seen in pilon or transitional ankle fractures. It serves as the primary tibial attachment site for the Anterior Inferior Tibiofibular Ligament (AITFL). Its corresponding fibular avulsion counterpart is the Wagstaffe-Le Fort fragment.

Question 2262

Topic: 8. Foot and Ankle

A 45-year-old diabetic male with Charcot neuroarthropathy presents with a chronic foot ulcer and suspected osteomyelitis of the calcaneus. X-rays are inconclusive due to preexisting bony destruction. What is the most accurate nuclear imaging modality for confirming chronic osteomyelitis in this setting?

. Three-phase Technetium-99m bone scan
. Indium-111 labeled white blood cell scan combined with Technetium-99m sulfur colloid marrow scan
. Gallium-67 citrate scan
. Fluorodeoxyglucose (FDG) PET scan alone
. Technetium-99m HMPAO scan without marrow imaging

Correct Answer & Explanation

. Indium-111 labeled white blood cell scan combined with Technetium-99m sulfur colloid marrow scan


Explanation

In cases of distorted bony anatomy like Charcot arthropathy, a combined leukocyte (WBC) and marrow scan is the most specific nuclear imaging modality. It differentiates true infection (discordant increased WBC uptake) from reactive marrow changes (concordant uptake).

Question 2263

Topic: 8. Foot and Ankle
A 40-year-old construction worker sustains a displaced intra-articular calcaneus fracture (Sanders Type III). Which of the following is the most significant intraoperative factor determining the long-term clinical outcome after open reduction and internal fixation?
. Restoration of Böhler's angle
. Quality of the posterior facet articular reduction
. Restoration of the calcaneal width
. Use of a locking plate rather than a non-locking plate
. Achieving rigid fixation of the anterior process

Correct Answer & Explanation

. Quality of the posterior facet articular reduction


Explanation

The anatomical reduction of the posterior facet articular surface is the most critical prognostic factor for functional outcomes. Failure to reduce the facet accurately significantly increases the risk of post-traumatic subtalar arthritis.

Question 2264

Topic: Midfoot & Hindfoot
A 25-year-old male sustains a severe inversion injury resulting in a Hawkins Type III talar neck fracture. What does this classification imply regarding the fracture displacement and the blood supply to the talar body?
. Displacement of the subtalar joint only; moderate risk of AVN
. Displacement of the subtalar and tibiotalar joints; very high risk of AVN
. Displacement of the talonavicular joint only; low risk of AVN
. Displacement of the subtalar, tibiotalar, and talonavicular joints; near 100% risk of AVN
. Nondisplaced fracture; negligible risk of AVN

Correct Answer & Explanation

. Displacement of the subtalar and tibiotalar joints; very high risk of AVN


Explanation

A Hawkins Type III fracture involves a talar neck fracture with dislocation of both the subtalar and tibiotalar joints. It carries a very high risk of avascular necrosis (frequently >80%) due to massive disruption of the talar body blood supply.

Question 2265

Topic: 8. Foot and Ankle
In evaluating a patient with a suspected intra-articular calcaneus fracture, lateral radiographs are obtained to measure Böhler's angle. Which of the following accurately describes the two lines used to construct this angle?
. A line from the highest point of the anterior process to the highest point of the posterior facet, and a line from the highest point of the posterior facet to the superior edge of the tuberosity
. A line from the inferior aspect of the calcaneocuboid joint to the inferior aspect of the tuberosity, and a line parallel to the plantar fascia
. A line from the anterior process to the medial malleolus, and a line from the posterior facet to the lateral malleolus
. A line parallel to the subtalar joint and a vertical line perpendicular to the ground
. A line from the highest point of the posterior facet to the lowest point of the cuboid, and a line intersecting the talonavicular joint

Correct Answer & Explanation

. A line from the highest point of the anterior process to the highest point of the posterior facet, and a line from the highest point of the posterior facet to the superior edge of the tuberosity


Explanation

Böhler's angle is measured on a lateral radiograph of the foot/calcaneus. It is formed by the intersection of two lines: one line drawn from the highest point of the anterior process to the highest point of the posterior facet, and a second line drawn from the highest point of the posterior facet to the highest point of the posterior tuberosity. The normal angle is 20 to 40 degrees. It is typically flattened (decreased) in intra-articular calcaneus fractures.

Question 2266

Topic: 8. Foot and Ankle
A 35-year-old male sustains a high-energy injury resulting in a displaced talar neck fracture with associated dislocation of the subtalar, tibiotalar, and talonavicular joints. According to the Hawkins classification, what is the type of fracture and the approximate risk of developing avascular necrosis (AVN) of the talar body?
. Hawkins Type II; 20-50% risk of AVN
. Hawkins Type III; 80-100% risk of AVN
. Hawkins Type III; 20-50% risk of AVN
. Hawkins Type IV; 80-100% risk of AVN
. Hawkins Type I; 0-10% risk of AVN

Correct Answer & Explanation

. Hawkins Type II; 20-50% risk of AVN


Explanation

The Hawkins classification for talar neck fractures: Type I is nondisplaced (0-10% AVN). Type II is displaced with subtalar dislocation (20-50% AVN). Type III is displaced with both subtalar and tibiotalar dislocation (50-100% AVN). Type IV involves displacement with subtalar, tibiotalar, and talonavicular dislocation. A Type IV fracture virtually obliterates all extraosseous blood supply to the talus (artery of the tarsal canal, artery of the tarsal sinus, and deltoid branches), carrying a risk of AVN approaching 80-100%.

Question 2267

Topic: 8. Foot and Ankle

Regarding the evaluation of a mangled lower extremity and the decision between amputation and limb salvage, which of the following statements best reflects the findings of the Lower Extremity Assessment Project (LEAP) study?

. A Mangled Extremity Severity Score (MESS) greater than 7 has a near 100% positive predictive value for mandatory amputation.
. Early amputation leads to significantly better long-term psychological outcomes and lower rates of depression compared to salvage.
. No single predictive scoring system (e.g., MESS, LSI) accurately predicts whether limb salvage or amputation will yield better functional outcomes.
. Limb salvage uniformly results in lower rates of rehospitalization and surgery compared to primary amputation.
. The presence of an insensate plantar aspect of the foot on initial presentation is an absolute indication for primary amputation.

Correct Answer & Explanation

. No single predictive scoring system (e.g., MESS, LSI) accurately predicts whether limb salvage or amputation will yield better functional outcomes.


Explanation

The landmark LEAP study demonstrated that traditional scoring systems (MESS, LSI, PSI) have low sensitivity and predictive value for determining the functional outcome of a mangled extremity. Furthermore, an initially insensate plantar foot does not preclude a good outcome with salvage, as sensation often returns. The study found no significant long-term difference in functional outcomes between the salvage and amputation groups, underscoring that no single score can dictate treatment; decisions must be highly individualized.

Question 2268

Topic: 8. Foot and Ankle
A 55-year-old patient is seeking a surgical consultation for a painful flatfoot deformity that has failed to respond to nonsteroidal anti-inflammatory drugs, shoe and activity modifications, and orthoses. The patient is of medium build, a nonsmoker, and has no history of diabetes mellitus. Radiographs are shown in Figures 43a through 43c. Based on these findings, treatment should consist of
. triple arthrodesis.
. lateral column lengthening with flexor digitorum longus tendon transfer.
. medial calcaneal displacement osteotomy, flexor digitorum longus transfer, and gastrocnemius recession.
. midfoot arthrodesis.
. subtalar arthroereisis with a Maxwell-Brancheau Arthroereisis titanium implant.

Correct Answer & Explanation

. midfoot arthrodesis.


Explanation

The patient has a degenerative collapse of the midfoot through the tarsometatarsal joints with significant forefoot abduction; therefore, a midfoot arthrodesis is required to address the arthritic joints and deformity at the tarsometatarsal articulation. All of the other procedures correct hindfoot deformities and therefore would not be appropriate treatment.

Question 2269

Topic: 8. Foot and Ankle
A 35-year-old man who snowboards sustained the injury shown in Figures 4a through 4c. What is the mechanism of injury?
. Inversion and external rotation
. Axial loading and internal rotation
. Plantar flexion, axial loading, and inversion
. Dorsiflexion and axial loading
. Dorsiflexion, axial loading, inversion, and external rotation

Correct Answer & Explanation

. Dorsiflexion, axial loading, inversion, and external rotation


Explanation

Fractures of the lateral process of the talus in snowboarders have been thought to result from pure dorsiflexion, inversion, and axial loading. In a cadaveric study, 10 cadavers were placed in fixed dorsiflexion and inversion with an axial load. This was combined with or without external rotation. No fractures occurred after axial loading in the dorsiflexed-inverted position. Fractures of the lateral process of the talus occurred in 75% of the specimens with the addition of external rotation.

Question 2270

Topic: 8. Foot and Ankle

In a patient with Charcot-Marie-Tooth (CMT) disease presenting with a progressive cavovarus foot deformity, which of the following specific muscle imbalances is the primary biomechanical driver of the hindfoot varus deformity?

. Strong peroneus longus overpowering a weak tibialis anterior
. Strong tibialis posterior overpowering a weak peroneus brevis
. Strong peroneus brevis overpowering a weak tibialis posterior
. Strong tibialis anterior overpowering a weak peroneus longus
. Strong gastrocnemius overpowering weak intrinsic foot muscles

Correct Answer & Explanation

. Strong peroneus brevis overpowering a weak tibialis posterior


Explanation

The cavovarus foot deformity in CMT is driven by specific muscle imbalances. The tibialis posterior and peroneus longus muscles are typically spared and relatively strong, whereas the tibialis anterior, peroneus brevis, and intrinsic muscles become weak. The hindfoot varus is primarily driven by the strong tibialis posterior overpowering the weak peroneus brevis. The forefoot cavus (plantarflexed first ray) is driven by the strong peroneus longus overpowering the weak tibialis anterior.

Question 2271

Topic: Midfoot & Hindfoot

A 28-year-old athlete sustains a purely ligamentous Lisfranc injury involving the first, second, and third tarsometatarsal joints. High-quality randomized controlled trials comparing primary arthrodesis of the medial three rays to open reduction and internal fixation (ORIF) for this specific injury pattern show primary arthrodesis is associated with which of the following?

. Higher rate of hardware removal
. Decreased rate of return to pre-injury level of sport
. Lower rate of secondary surgeries
. Increased risk of adjacent segment arthritis at 1 year
. Inferior functional scores at 2 years follow-up

Correct Answer & Explanation

. Lower rate of secondary surgeries


Explanation

For purely ligamentous Lisfranc injuries, primary arthrodesis of the medial three rays (first, second, and third TMT joints) has been shown to yield equivalent or better functional outcomes compared to ORIF, while significantly decreasing the rate of secondary surgeries (due to hardware removal or subsequent salvage arthrodesis for post-traumatic arthritis).

Question 2272

Topic: 8. Foot and Ankle

Recent meta-analyses evaluating operative versus nonoperative management of acute Achilles tendon ruptures utilizing modern, accelerated functional rehabilitation protocols demonstrate which of the following?

. Operative management significantly reduces the overall re-rupture rate
. Nonoperative management is associated with a significantly higher rate of sural nerve injury
. There is no clinically significant difference in re-rupture rates between the two groups
. Operative management results in superior plantarflexion strength at 2 years
. Nonoperative management has a significantly higher risk of deep vein thrombosis

Correct Answer & Explanation

. There is no clinically significant difference in re-rupture rates between the two groups


Explanation

When modern functional rehabilitation protocols (early weight-bearing and early functional range of motion) are strictly employed, the re-rupture rates between operative and nonoperative management of acute Achilles tendon ruptures are not statistically different. Operative management is associated with a higher risk of soft tissue complications, such as infection and sural nerve injury.

Question 2273

Topic: Midfoot & Hindfoot
A 30-year-old male sustains a high-energy motor vehicle collision resulting in a Hawkins Type III talar neck fracture. By definition, which of the following joints are dislocated in this injury pattern, and what is the classic historical rate of avascular necrosis (AVN) of the talar body?
. Subtalar joint only; 20-30% AVN risk
. Subtalar and tibiotalar joints; 40-50% AVN risk
. Subtalar and tibiotalar joints; nearly 100% AVN risk
. Subtalar, tibiotalar, and talonavicular joints; nearly 100% AVN risk
. Subtalar, tibiotalar, and talonavicular joints; 40-50% AVN risk

Correct Answer & Explanation

. Subtalar and tibiotalar joints; nearly 100% AVN risk


Explanation

The Hawkins classification for talar neck fractures: Type I is nondisplaced (0-15% AVN). Type II involves subluxation or dislocation of the subtalar joint (20-50% AVN). Type III involves dislocation of both the subtalar and tibiotalar joints (historically associated with a nearly 100% risk of AVN, though modern series report 70-100%). Type IV adds talonavicular joint dislocation.

Question 2274

Topic: 8. Foot and Ankle
A 55-year-old female is diagnosed with Stage IIB adult acquired flatfoot deformity (posterior tibial tendon dysfunction). Clinical examination reveals a flexible deformity with marked hindfoot valgus and significant forefoot abduction (uncovering of the talar head >40%). In addition to a flexor digitorum longus (FDL) transfer and medial displacement calcaneal osteotomy (MDCO), which adjunctive procedure is most indicated to specifically correct the transverse plane (abduction) deformity?
. Medial cuneiform plantar-flexion osteotomy (Cotton)
. Lateral column lengthening (Evans osteotomy)
. Subtalar arthrodesis
. First tarsometatarsal arthrodesis (Lapidus)
. Spring ligament reconstruction

Correct Answer & Explanation

. Lateral column lengthening (Evans osteotomy)


Explanation

Stage IIB adult acquired flatfoot deformity is characterized by a flexible deformity with significant forefoot abduction (transverse plane deformity). While an MDCO corrects the coronal plane (valgus) deformity, a lateral column lengthening (such as an Evans calcaneal osteotomy) is specifically indicated to correct the substantial transverse plane abduction by effectively lengthening the lateral column and rotating the midfoot back over the talus.

Question 2275

Topic: 8. Foot and Ankle

Osteochondral lesions of the talus frequently occur in distinct anatomical patterns associated with specific mechanisms of injury. Which of the following accurately describes the classical morphological characteristics and mechanism of a medial talar dome lesion?

. Anterior location, shallow and wafer-shaped, caused by dorsiflexion and inversion
. Posterior location, deep and cup-shaped, caused by plantarflexion and inversion
. Anterior location, deep and cup-shaped, caused by plantarflexion and eversion
. Posterior location, shallow and wafer-shaped, caused by dorsiflexion and eversion
. Central location, shallow and wafer-shaped, caused by axial loading in neutral

Correct Answer & Explanation

. Posterior location, deep and cup-shaped, caused by plantarflexion and inversion


Explanation

The classical mnemonic for osteochondral lesions of the talus is 'DIAL a PIMP'. DIAL: Dorsiflexion Inversion = Anterior Lateral lesions (which are typically shallow and wafer-shaped). PIMP: Plantarflexion Inversion = Medial Posterior lesions (which are typically deep and cup-shaped). Therefore, medial lesions are characteristically posterior, deep/cup-shaped, and result from plantarflexion and inversion.

Question 2276

Topic: 8. Foot and Ankle

A 52-year-old male runner presents with dorsal foot pain and limited great toe dorsiflexion. Radiographs reveal moderate dorsal osteophytes and mild joint space narrowing at the first metatarsophalangeal (MTP) joint, consistent with Grade 2 hallux rigidus (Coughlin and Shurnas classification). He has 25 degrees of active dorsiflexion. Which of the following is the most appropriate initial surgical intervention if nonoperative management fails?

. First metatarsophalangeal joint arthrodesis
. Dorsal cheilectomy
. Keller resection arthroplasty
. Synthetic interpositional arthroplasty
. First tarsometatarsal arthrodesis (Lapidus)

Correct Answer & Explanation

. Dorsal cheilectomy


Explanation

Grade 2 hallux rigidus features mild to moderate joint space narrowing, dorsal osteophytes, and preserved plantar cartilage with some maintained range of motion (>15-20 degrees dorsiflexion). If conservative measures fail, a dorsal cheilectomy (removal of the dorsal osteophytes and dorsal 20-30% of the metatarsal head) is the procedure of choice. Arthrodesis is reserved for Grade 3 (severe narrowing) or Grade 4 (pain throughout the entire range of motion).

Question 2277

Topic: 8. Foot and Ankle

The primary biomechanical stability of the Lisfranc complex relies heavily on the Lisfranc ligament. Which of the following accurately describes the anatomic origin and insertion of this critical structure?

. Dorsal aspect of the medial cuneiform to the dorsal base of the second metatarsal
. Plantar aspect of the middle cuneiform to the plantar base of the second metatarsal
. Plantar-lateral aspect of the medial cuneiform to the plantar-medial base of the second metatarsal
. Base of the first metatarsal to the base of the second metatarsal
. Distal navicular to the plantar base of the first metatarsal

Correct Answer & Explanation

. Plantar-lateral aspect of the medial cuneiform to the plantar-medial base of the second metatarsal


Explanation

The Lisfranc ligament is the strongest ligament in the midfoot, originating on the plantar-lateral aspect of the medial cuneiform and inserting on the plantar-medial aspect of the second metatarsal base. There is no direct ligamentous connection between the bases of the first and second metatarsals.

Question 2278

Topic: Midfoot & Hindfoot

A 52-year-old female is diagnosed with Stage IIB posterior tibial tendon dysfunction (PTTD), demonstrating a flexible flatfoot with severe forefoot abduction and greater than 30% talonavicular uncoverage on radiographs. In addition to a flexor digitorum longus (FDL) transfer and medial displacement calcaneal osteotomy (MDCO), what additional procedure is biomechanically required to correct her specific deformity?

. Evans lateral column lengthening
. First metatarsophalangeal arthrodesis
. Talonavicular arthrodesis
. Gastrocnemius recession alone
. Subtalar arthrodesis

Correct Answer & Explanation

. Evans lateral column lengthening


Explanation

Stage IIB PTTD involves a flexible flatfoot with significant forefoot abduction (talonavicular uncoverage >30%). An Evans lateral column lengthening is required in addition to MDCO and FDL transfer to effectively correct the severe forefoot abduction.

Question 2279

Topic: 8. Foot and Ankle

At 6 weeks post-injury, a 28-year-old patient who underwent open reduction and internal fixation for a Hawkins Type II talar neck fracture undergoes routine follow-up radiographs. A distinct subchondral radiolucent band is noted in the dome of the talus. What is the clinical significance of this radiographic finding?

. It indicates early hardware failure and loss of fixation
. It demonstrates subchondral osteopenia, which confirms intact vascularity to the talar dome
. It strongly suggests impending avascular necrosis (AVN)
. It indicates a nonunion of the talar neck
. It is pathognomonic for an unrecognized subtalar joint dislocation

Correct Answer & Explanation

. It demonstrates subchondral osteopenia, which confirms intact vascularity to the talar dome


Explanation

The subchondral radiolucent band is known as Hawkins' sign. It represents subchondral osteopenia due to bone resorption, which is a physiologic process that can only occur if the vascular supply to the talar dome remains intact, making it a reliable negative predictor for AVN.

Question 2280

Topic: 8. Foot and Ankle

Recent high-quality, randomized controlled trials comparing operative versus non-operative management of acute Achilles tendon ruptures demonstrate which of the following regarding complication rates when patients undergo early functional rehabilitation?

. Operative repair has a significantly lower re-rupture rate.
. Non-operative management with early functional weight-bearing has an equivalent re-rupture rate to operative repair.
. Non-operative management is associated with significantly higher rates of deep vein thrombosis.
. Operative management yields significantly greater plantarflexion strength at 5 years.
. Prolonged cast immobilization yields lower re-rupture rates than early functional rehab.

Correct Answer & Explanation

. Non-operative management with early functional weight-bearing has an equivalent re-rupture rate to operative repair.


Explanation

Modern literature, notably the WILL trial and similar studies, shows that when early functional rehabilitation protocols are utilized, the re-rupture rates between operative and non-operative management of Achilles tendon ruptures are statistically equivalent.