Menu

1. General Principles & Basic Science MCQs

Practice Set 764 of 789

This practice set contains high-yield board review questions covering key concepts in 1. General Principles & Basic Science. Each clinical scenario is designed to test your diagnostic and management skills relevant to this subspecialty.

Question 15261

Topic: 1. General Principles & Basic Science

A 30-year-old carpenter lacerates his index finger with a utility knife, dividing both the flexor digitorum superficialis and profundus tendons in Zone II. Following primary surgical repair, what is the most appropriate postoperative rehabilitation protocol?

. Complete immobilization in a cast for 6 weeks
. Early active mobilization protocol
. Passive extension and active flexion exercises
. Unrestricted immediate return to work
. Active extension against resistance

Correct Answer & Explanation

. Early active mobilization protocol

Explanation

Modern zone II flexor tendon repairs rely on early active mobilization protocols (e.g., modified Duran, Kleinert, or early active motion) to minimize peritendinous adhesions and optimize functional outcomes. Complete immobilization leads to severe tendon gliding stiffness.

Question 15262

Topic: Biology, Genetics & Bone Healing

A 72-year-old woman with a T-score of -3.1 at the lumbar spine is prescribed alendronate. Which of the following describes the primary cellular mechanism of action of this medication?

. Stimulation of osteoblast differentiation via Wnt signaling
. Inhibition of osteoclast function by disrupting the mevalonate pathway
. Direct binding to RANK ligand to prevent osteoclast activation
. Agonism of estrogen receptors on osteoblasts
. Inhibition of sclerostin leading to increased bone formation

Correct Answer & Explanation

. Inhibition of osteoclast function by disrupting the mevalonate pathway

Explanation

Alendronate is a nitrogen-containing bisphosphonate. It inhibits farnesyl pyrophosphate synthase in the mevalonate pathway, which disrupts osteoclast formation, function, and survival, thereby reducing overall bone resorption.

Question 15263

Topic: Biology, Genetics & Bone Healing

A 33-year-old woman presents with knee pain. Radiographs reveal an eccentric, lytic, well-defined epiphyseal lesion extending to the subchondral bone of the distal femur without a sclerotic margin. Histology shows multinucleated giant cells in a stroma of mononuclear cells. Which medication is FDA-approved for the systemic treatment of this condition when it is surgically unresectable?

. Methotrexate
. Doxorubicin
. Denosumab
. Imatinib
. Zoledronic acid

Correct Answer & Explanation

. Denosumab

Explanation

Denosumab, a monoclonal antibody against RANKL, is approved for treating locally advanced or unresectable Giant Cell Tumors of bone. It inhibits the osteoclast-like giant cells and the RANKL-expressing stromal cells, severely halting tumor progression.

Question 15264

Topic: Biology, Genetics & Bone Healing

Which of the following molecules is secreted by osteoblasts to directly inhibit osteoclastogenesis by acting as a decoy receptor?

. Osteopontin
. Macrophage colony-stimulating factor (M-CSF)
. Osteoprotegerin (OPG)
. Sclerostin
. Cathepsin K

Correct Answer & Explanation

. Osteoprotegerin (OPG)

Explanation

Osteoprotegerin (OPG) is a soluble decoy receptor produced by osteoblasts that binds to RANKL. By doing so, it prevents RANKL from interacting with the RANK receptor on osteoclast precursors, thereby halting osteoclast differentiation and bone resorption.

Question 15265

Topic: Biomechanics & Biomaterials

A specialized orthopedic ligament graft is subjected to a constant, continuous displacement over time during biomechanical testing. The force required to maintain this constant displacement progressively decreases. This viscoelastic property is best defined as:

. Creep
. Stress relaxation
. Hysteresis
. Fatigue
. Isotropic behavior

Correct Answer & Explanation

. Stress relaxation

Explanation

Stress relaxation is a viscoelastic property where the internal stress (force) of a tissue decreases over time when it is held at a constant strain (displacement). Creep, conversely, is increasing deformation under a constant load.

Question 15266

Topic: Surgical Anatomy & Approaches

The anterolateral approach to the distal fibula utilizes an internervous plane between muscles supplied by which of the following nerves?

. Deep peroneal nerve and superficial peroneal nerve
. Tibial nerve and deep peroneal nerve
. Superficial peroneal nerve and sural nerve
. Tibial nerve and superficial peroneal nerve
. Femoral nerve and sciatic nerve

Correct Answer & Explanation

. Deep peroneal nerve and superficial peroneal nerve

Explanation

Correct Answer: Deep peroneal nerve and superficial peroneal nerveThe anterolateral approach to the fibula utilizes the internervous plane between the anterior compartment (innervated by the deep peroneal nerve) and the lateral compartment (innervated by the superficial peroneal nerve). This plane allows for safe exposure of the fibula while respecting the neurovascular supply of the leg.

Question 15267

Topic: Surgical Anatomy & Approaches

When performing an anterolateral approach to the distal fibula, the surgeon utilizes an internervous plane between the anterior and lateral compartments. Which two nerves supply the musculature defining this interval?

. Tibial nerve and deep peroneal nerve
. Superficial peroneal nerve and deep peroneal nerve
. Sural nerve and superficial peroneal nerve
. Saphenous nerve and deep peroneal nerve
. Tibial nerve and superficial peroneal nerve

Correct Answer & Explanation

. Superficial peroneal nerve and deep peroneal nerve

Explanation

Correct Answer: Superficial peroneal nerve and deep peroneal nerveThe approach utilizes the interval between the anterior compartment (innervated by the deep peroneal nerve) and the lateral compartment (innervated by the superficial peroneal nerve). The text specifies this interval involves the tibialis anterior/extensors and the peroneus longus/brevis.

Question 15268

Topic: 1. General Principles & Basic Science

During a standard anterolateral approach to the distal fibula, a longitudinal incision is made. Which nerve typically crosses the surgical field anteriorly and must be meticulously identified and protected?

. Sural nerve
. Deep peroneal nerve
. Superficial peroneal nerve
. Saphenous nerve
. Lateral plantar nerve

Correct Answer & Explanation

. Superficial peroneal nerve

Explanation

Correct Answer: Superficial peroneal nerveThe text highlights that during the anterolateral approach to the lateral malleolus, careful consideration must be given to the superficial peroneal nerve, which typically crosses the surgical field anteriorly and must be protected.

Question 15269

Topic: 1. General Principles & Basic Science

While Magnetic Resonance Imaging (MRI) is preferred for evaluating soft tissue injuries like syndesmotic tears, which imaging modality is specifically indicated to assess syndesmotic integrity if dynamic instability is suspected?

. Computed Tomography (CT) scan
. Ultrasound
. Stress radiographs
. Bone scintigraphy
. Weight-bearing plain radiographs

Correct Answer & Explanation

. Stress radiographs

Explanation

Correct Answer: Stress radiographsAccording to the text, while MRI is preferred for evaluating soft tissue injuries, stress radiographs are specifically used to assess syndesmotic integrity if instability is suspected clinically but not apparent on static imaging.

Question 15270

Topic: Surgical Anatomy & Approaches

When performing an anterolateral approach for open reduction and internal fixation of a lateral malleolus fracture, the surgeon utilizes an internervous plane. Between which two muscle compartments does this plane lie, and which nerve is at greatest risk during the superficial dissection?

. Anterior and lateral compartments; deep peroneal nerve
. Lateral and superficial posterior compartments; sural nerve
. Anterior and lateral compartments; superficial peroneal nerve
. Lateral and deep posterior compartments; tibial nerve
. Anterior and deep posterior compartments; saphenous nerve

Correct Answer & Explanation

. Anterior and lateral compartments; superficial peroneal nerve

Explanation

Correct Answer: CThe anterolateral approach to the distal fibula utilizes the internervous plane between the anterior compartment (innervated by the deep peroneal nerve) and the lateral compartment (innervated by the superficial peroneal nerve). During the superficial dissection, the superficial peroneal nerve is at significant risk as it pierces the deep fascia to become subcutaneous, typically crossing the surgical field anteriorly from lateral to medial. It must be meticulously identified and protected.

Question 15271

Topic: Surgical Anatomy & Approaches

When performing an anterolateral approach to the distal fibula for fracture fixation, the internervous plane lies between which two muscle compartments?

. Anterior and deep posterior
. Lateral and superficial posterior
. Anterior and lateral
. Lateral and deep posterior
. Superficial posterior and deep posterior

Correct Answer & Explanation

. Anterior and lateral

Explanation

Correct Answer: Anterior and lateralThe anterolateral approach to the distal fibula utilizes the internervous plane between the anterior compartment (containing the tibialis anterior and extensors, innervated by the deep peroneal nerve) and the lateral compartment (containing the peroneus longus and brevis, innervated by the superficial peroneal nerve).

Question 15272

Topic: 1. General Principles & Basic Science

During the anterolateral approach to the lateral malleolus, which nerve is at greatest risk of iatrogenic injury and must be meticulously identified and protected?

. Sural nerve
. Deep peroneal nerve
. Saphenous nerve
. Superficial peroneal nerve
. Tibial nerve

Correct Answer & Explanation

. Superficial peroneal nerve

Explanation

Correct Answer: Superficial peroneal nerveDuring the anterolateral approach to the lateral malleolus, careful consideration must be given to the superficial peroneal nerve. This nerve typically crosses the surgical field anteriorly within the subcutaneous tissue or superficial fascia and must be identified and gently retracted to prevent iatrogenic injury.

Question 15273

Topic: 1. General Principles & Basic Science

Which of the following ligaments is a component of the deep layer of the deltoid ligament complex?

. Tibiocalcaneal ligament
. Tibionavicular ligament
. Superficial posterior tibiotalar ligament
. Deep anterior tibiotalar ligament
. Spring ligament

Correct Answer & Explanation

. Deep anterior tibiotalar ligament

Explanation

Correct Answer: Deep anterior tibiotalar ligamentThe deltoid ligament is a robust medial stabilizing structure composed of superficial and deep layers. The superficial layer includes the tibiocalcaneal, tibionavicular, and superficial posterior tibiotalar ligaments. The deep layer is composed of the deep posterior tibiotalar and deep anterior tibiotalar ligaments.

Question 15274

Topic: Surgical Anatomy & Approaches

When performing an anterolateral approach to the distal fibula, the internervous plane utilized lies between muscles innervated by which two nerves?

. Deep peroneal nerve and superficial peroneal nerve
. Superficial peroneal nerve and sural nerve
. Tibial nerve and deep peroneal nerve
. Tibial nerve and superficial peroneal nerve
. Sural nerve and saphenous nerve

Correct Answer & Explanation

. Deep peroneal nerve and superficial peroneal nerve

Explanation

Correct Answer: AThe anterolateral approach utilizes the interval between the anterior compartment (tibialis anterior, extensors) and the lateral compartment (peroneus longus and brevis). The anterior compartment is innervated by the deep peroneal nerve, while the lateral compartment is innervated by the superficial peroneal nerve.

Question 15275

Topic: 1. General Principles & Basic Science

During the anterolateral approach to the lateral malleolus, which nerve is at greatest risk of iatrogenic injury as it typically crosses the surgical field anteriorly?

. Sural nerve
. Deep peroneal nerve
. Superficial peroneal nerve
. Saphenous nerve
. Tibial nerve

Correct Answer & Explanation

. Superficial peroneal nerve

Explanation

Correct Answer: CWhen making a longitudinal incision over the distal fibula, careful consideration must be given to the superficial peroneal nerve. It typically crosses the surgical field anteriorly within the subcutaneous tissue or superficial fascia and must be meticulously identified and protected.

Question 15276

Topic: 1. General Principles & Basic Science

A patient presents with recurrent snapping over the lateral malleolus after an inversion injury. Examination reveals peroneal tendon subluxation. Which anatomical structure is the primary restraint to this pathology?

. Inferior extensor retinaculum
. Superior peroneal retinaculum
. Calcaneofibular ligament
. Anterior talofibular ligament
. Peroneus brevis muscle belly

Correct Answer & Explanation

. Superior peroneal retinaculum

Explanation

The superior peroneal retinaculum is the primary dynamic and static restraint that keeps the peroneal tendons within the retromalleolar groove. Disruption leads to tendon subluxation.

Question 15277

Topic: Infection, Pharmacology & VTE

A 62-year-old diabetic patient presents with a chronic plantar ulcer under the first metatarsal head. Which of the following clinical findings or tests has the highest positive predictive value for diagnosing underlying osteomyelitis in this specific setting?

. Erythrocyte sedimentation rate > 40 mm/hr
. Positive probe-to-bone test
. Plain radiography showing soft tissue swelling
. C-reactive protein > 10 mg/L
. Presence of purulent drainage

Correct Answer & Explanation

. Positive probe-to-bone test

Explanation

A positive probe-to-bone test (palpating hard, gritty bone with a sterile blunt probe through an ulcer) has a remarkably high positive predictive value (approaching 90%) for underlying osteomyelitis in diabetic foot infections.

Question 15278

Topic: Biology, Genetics & Bone Healing

A 12-year-old girl is found to have a pedunculated bony mass on her proximal tibia that points away from the joint line.

Which of the following best describes the embryologic/developmental origin of this lesion?

. Intramembranous ossification of the periosteum
. Aberrant displacement of physeal cartilage through the node of Ranvier
. Hamartomatous proliferation of osteoblasts
. Neoplastic transformation of remaining notochordal cells
. Reactive bone formation secondary to repetitive microtrauma

Correct Answer & Explanation

. Aberrant displacement of physeal cartilage through the node of Ranvier

Explanation

Osteochondromas are developmental anomalies resulting from the herniation of a fragment of the epiphyseal growth plate through the periosteal cuff (node of Ranvier). They grow via endochondral ossification.

Question 15279

Topic: Biology, Genetics & Bone Healing

A 12-year-old boy with multiple hereditary exostoses (MHE) is evaluated for bilateral knee bumps. The underlying genetic defect in this condition primarily impairs which of the following cellular processes?

. Wnt/B-catenin signaling pathway
. Heparan sulfate biosynthesis
. Fibroblast growth factor receptor 3 (FGFR3) activation
. RANK-RANKL pathway interactions
. Type I collagen synthesis

Correct Answer & Explanation

. Heparan sulfate biosynthesis

Explanation

MHE is caused by autosomal dominant mutations in the EXT1 or EXT2 genes. These genes encode glycosyltransferases essential for heparan sulfate biosynthesis, which regulates chondrocyte proliferation and differentiation.

Question 15280

Topic: Biology, Genetics & Bone Healing

A 25-year-old male sustains a subtrochanteric fracture after a minor fall. Radiographs show a "bone-within-a-bone" appearance and a densely sclerotic skeleton. What is the primary cellular defect responsible for this condition?

. Decreased osteoblast proliferation
. Impaired osteoclast acidification
. Defective collagen type 1 synthesis
. Abnormal endochondral ossification
. Overactive osteocyte apoptosis

Correct Answer & Explanation

. Impaired osteoclast acidification

Explanation

Osteopetrosis is caused by impaired osteoclast function, often due to a defect in the chloride channel (CLCN7) or carbonic anhydrase II, which disrupts acidification at the ruffled border. This leads to impaired bone resorption, resulting in dense but brittle bones that are prone to fracture.

Test Yourself

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

On this Page