Menu

1. General Principles & Basic Science MCQs

Practice Set 365 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 7281

Topic: Surgical Anatomy & Approaches

The ilioinguinal approach provides excellent exposure of the anterior column of the acetabulum. The exposure is traditionally divided into three distinct anatomical 'windows'. Which structures are primarily located and mobilized within the middle window?

. Iliopsoas muscle and femoral nerve
. External iliac artery and vein
. Spermatic cord and rectus abdominis
. Obturator nerve and vessels
. Sciatic nerve and inferior gluteal vessels

Correct Answer & Explanation

. Iliopsoas muscle and femoral nerve

Explanation

The middle window of the ilioinguinal approach is defined by the iliopectineal fascia laterally and the external iliac vessels medially. It requires careful mobilization and protection of the external iliac artery and vein to access the pelvic brim.

Question 7282

Topic: Surgical Anatomy & Approaches

Following a technically challenging hip arthroscopy performed on a traction table, the patient reports severe perineal numbness and erectile dysfunction. This complication is most likely caused by direct compression of which nerve against the perineal post?

. Lateral femoral cutaneous nerve
. Sciatic nerve
. Pudendal nerve
. Ilioinguinal nerve
. Genitofemoral nerve

Correct Answer & Explanation

. Lateral femoral cutaneous nerve

Explanation

Pudendal nerve neuropraxia is a well-documented complication of prolonged traction against a rigid perineal post during hip arthroscopy or fracture table positioning. It typically manifests as perineal numbness and transient sexual dysfunction.

Question 7283

Topic: Surgical Anatomy & Approaches

Which ligament is considered the strongest ligament in the human body and acts as the primary restraint to hyperextension of the hip joint?

. Ischiofemoral ligament
. Pubofemoral ligament
. Iliofemoral ligament
. Ligamentum teres
. Transverse acetabular ligament

Correct Answer & Explanation

. Ischiofemoral ligament

Explanation

The iliofemoral ligament (Y ligament of Bigelow) is the thickest and strongest ligament in the body. It spans from the AIIS to the intertrochanteric line, becoming taut in hip extension and acting as the primary restraint to hyperextension.

Question 7284

Topic: Surgical Anatomy & Approaches

To minimize tension on the sciatic nerve while placing retractors during a Kocher-Langenbeck approach for acetabular fracture fixation, the ipsilateral lower extremity should be placed in which of the following positions?

. Hip flexed and knee flexed
. Hip flexed and knee extended
. Hip extended and knee flexed
. Hip extended and knee extended
. Hip abducted and knee extended

Correct Answer & Explanation

. Hip flexed and knee flexed

Explanation

The sciatic nerve courses posterior to the hip joint and posterior to the knee. Positioning the leg with the hip extended and the knee flexed introduces maximum slack into the nerve, thereby reducing the risk of iatrogenic traction injury during posterior retractor placement.

Question 7285

Topic: 1. General Principles & Basic Science

During a surgical approach to the hip, understanding the vascular anatomy is critical to prevent avascular necrosis of the femoral head. Which of the following branches provides the predominant blood supply to the adult femoral head?

. Ascending branch of the medial femoral circumflex artery
. Transverse branch of the lateral femoral circumflex artery
. Deep branch of the medial femoral circumflex artery
. Artery of the ligamentum teres
. Inferior gluteal artery

Correct Answer & Explanation

. Ascending branch of the medial femoral circumflex artery

Explanation

The deep branch of the medial femoral circumflex artery (MFCA) provides the primary blood supply to the adult femoral head via the lateral epiphyseal arteries. Injury to this vessel during posterior hip approaches significantly increases the risk of avascular necrosis.

Question 7286

Topic: Surgical Anatomy & Approaches

The ilioinguinal approach to the acetabulum provides access to the anterior column. The 'middle window' of this approach is bounded by which of the following structures?

. Lateral to the iliopsoas muscle and femoral nerve
. Between the iliopectineal fascia and the external iliac vessels
. Medial to the external iliac vessels and lateral to the spermatic cord
. Between the tensor fasciae latae and sartorius
. Between the internal and external iliac arteries

Correct Answer & Explanation

. Lateral to the iliopsoas muscle and femoral nerve

Explanation

The middle window of the ilioinguinal approach is located between the iliopectineal fascia (which overlies the iliopsoas and femoral nerve) laterally, and the external iliac vessels medially. It allows access to the pelvic brim and quadrilateral plate.

Question 7287

Topic: Surgical Anatomy & Approaches

During an anterior intrapelvic (modified Stoppa) approach, the surgeon must be cautious of the 'corona mortis'. This vascular structure represents an anastomosis between which two systems?

. Femoral and internal pudendal arteries
. External iliac and internal iliac systems
. Deep circumflex iliac and inferior epigastric arteries
. External pudendal and obturator arteries
. Superior gluteal and inferior gluteal arteries

Correct Answer & Explanation

. Femoral and internal pudendal arteries

Explanation

The corona mortis is a vascular anastomosis between the external iliac system (inferior epigastric artery/vein) and the internal iliac system (obturator artery/vein). It crosses the superior pubic ramus and is at high risk of iatrogenic injury during anterior pelvic approaches.

Question 7288

Topic: Surgical Anatomy & Approaches

A direct anterior (Smith-Petersen) approach is used for a hip arthroplasty. During the superficial dissection, which nerve is most at risk of iatrogenic injury?

. Femoral nerve
. Obturator nerve
. Lateral femoral cutaneous nerve
. Superior gluteal nerve
. Sciatic nerve

Correct Answer & Explanation

. Femoral nerve

Explanation

The lateral femoral cutaneous nerve runs superficially across the sartorius or in the interval between the sartorius and tensor fasciae latae. It is highly susceptible to stretching or transection during the direct anterior approach.

Question 7289

Topic: 1. General Principles & Basic Science

A patient exhibits a positive Trendelenburg sign after sustaining a penetrating injury to the posterior pelvis. The injured nerve is responsible for innervating which of the following muscle groups?

. Gluteus maximus and piriformis
. Gluteus medius, gluteus minimus, and tensor fasciae latae
. Obturator internus and gemelli
. Quadratus femoris and obturator externus
. Iliopsoas and pectineus

Correct Answer & Explanation

. Gluteus maximus and piriformis

Explanation

A positive Trendelenburg sign indicates weakness of the hip abductors, which are innervated by the superior gluteal nerve. This nerve innervates the gluteus medius, gluteus minimus, and tensor fasciae latae.

Question 7290

Topic: 1. General Principles & Basic Science

The artery of the ligamentum teres provides a small and variable blood supply to the femoral head. It is typically a terminal branch of which of the following arteries?

. Medial femoral circumflex artery
. Lateral femoral circumflex artery
. Obturator artery
. Inferior gluteal artery
. Superior gluteal artery

Correct Answer & Explanation

. Medial femoral circumflex artery

Explanation

The artery of the ligamentum teres is a branch of the obturator artery. While it provides minimal blood supply to the adult femoral head, it is a more significant contributor in children.

Question 7291

Topic: Surgical Anatomy & Approaches

When performing a posterior (Kocher-Langenbeck) approach to the acetabulum, what is the true internervous plane utilized?

. Between the gluteus maximus and gluteus medius
. Between the gluteus medius and tensor fasciae latae
. Between the sartorius and tensor fasciae latae
. Between the rectus femoris and iliopsoas
. There is no true internervous plane

Correct Answer & Explanation

. Between the gluteus maximus and gluteus medius

Explanation

The Kocher-Langenbeck approach has no true internervous plane. It relies on a blunt muscle split of the gluteus maximus, which is entirely innervated by the inferior gluteal nerve.

Question 7292

Topic: Surgical Anatomy & Approaches

During fracture fixation via the modified Stoppa approach, mobilization of the obturator neurovascular bundle is required to visualize the quadrilateral plate. Through which structure does this bundle exit the true pelvis?

. Greater sciatic foramen
. Lesser sciatic foramen
. Obturator canal
. Under the inguinal ligament
. Greater trochanteric notch

Correct Answer & Explanation

. Greater sciatic foramen

Explanation

The obturator nerve and vessels exit the pelvis through the obturator canal, which is a small opening situated at the superolateral aspect of the obturator foramen.

Question 7293

Topic: Surgical Anatomy & Approaches

During an anterolateral (Watson-Jones) approach to the hip, which vascular structure crosses the surgical interval and typically requires ligation to achieve adequate deep exposure?

. Ascending branch of the lateral femoral circumflex artery
. Descending branch of the medial femoral circumflex artery
. Transverse branch of the lateral femoral circumflex artery
. Deep branch of the medial femoral circumflex artery
. Recurrent branch of the obturator artery

Correct Answer & Explanation

. Ascending branch of the lateral femoral circumflex artery

Explanation

The ascending branch of the lateral femoral circumflex artery consistently crosses the interval between the tensor fasciae latae and the gluteus medius during the Watson-Jones approach and must be ligated for safe deep exposure.

Question 7294

Topic: Surgical Anatomy & Approaches

The hip joint capsule is reinforced by several strong ligaments. Which ligament is the strongest in the body and acts primarily to prevent hyperextension of the hip joint?

. Ischiofemoral ligament
. Pubofemoral ligament
. Iliofemoral ligament
. Ligamentum teres
. Transverse acetabular ligament

Correct Answer & Explanation

. Ischiofemoral ligament

Explanation

The iliofemoral ligament (Y ligament of Bigelow) is the strongest ligament in the human body. It spans anteriorly over the hip joint capsule and tightly restricts hyperextension of the hip.

Question 7295

Topic: Biology, Genetics & Bone Healing

In mature lamellar bone, osteons are bounded by a structurally distinct boundary that separates them from the surrounding interstitial lamellae. This histological structure is known as the:

. Volkmann canal
. Haversian canal
. Cement line
. Sharpey fiber
. Howship lacuna

Correct Answer & Explanation

. Volkmann canal

Explanation

The cement line marks the outer boundary of an osteon in cortical bone. It indicates the physiological reversal point where osteoclastic bone resorption stopped and osteoblastic new bone formation began.

Question 7296

Topic: Surgical Anatomy & Approaches

A patient with suspected anterior hip instability requires an assessment of the hip capsular ligaments. Which ligament is the thickest in the body and serves as the primary restraint to hip extension and external rotation?

. Pubofemoral ligament
. Ischiofemoral ligament
. Iliofemoral ligament
. Ligamentum teres
. Zona orbicularis

Correct Answer & Explanation

. Pubofemoral ligament

Explanation

The iliofemoral ligament (Y ligament of Bigelow) spans the anterior hip capsule and is the strongest ligament in the human body. It severely limits hip extension and anterior translation of the femoral head.

Question 7297

Topic: 1. General Principles & Basic Science

The sternoclavicular (SC) joint relies heavily on ligamentous stabilizers due to poor bony congruity. Which ligament acts as the primary restraint to superior displacement of the medial clavicle?

. Anterior sternoclavicular ligament
. Interclavicular ligament
. Costoclavicular ligament
. Posterior sternoclavicular ligament
. Intra-articular disc ligament

Correct Answer & Explanation

. Anterior sternoclavicular ligament

Explanation

The costoclavicular ligament (also known as the rhomboid ligament) strongly anchors the inferior aspect of the medial clavicle to the first rib. It is the primary restraint to superior translation of the medial clavicle.

Question 7298

Topic: Biology, Genetics & Bone Healing

Regarding the microscopic structure of cortical bone, which of the following statements most accurately describes Volkmann's canals?

. They run parallel to the long axis of the bone and contain osteoprogenitor cells.
. They are concentric rings of calcified matrix surrounding a central vascular channel.
. They run perpendicular to the long axis of the bone, connecting Haversian canals to the periosteum.
. They represent the boundary between older interstitial lamellae and newly formed osteons.
. They are primary sites of endochondral ossification during fracture healing.

Correct Answer & Explanation

. They run parallel to the long axis of the bone and contain osteoprogenitor cells.

Explanation

Volkmann's canals run transversely through cortical bone to connect the longitudinal Haversian canals with the periosteal and endosteal blood supplies. This network ensures adequate vascularity throughout the dense osteonal system.

Question 7299

Topic: 1. General Principles & Basic Science

The screw-home mechanism of the knee is essential for locking the joint in terminal extension. Which of the following kinematic coupled motions occurs during the final 20 degrees of open-chain knee extension?

. Internal rotation of the tibia relative to the femur
. External rotation of the tibia relative to the femur
. Internal rotation of the femur relative to the tibia
. Anterior translation of the femur relative to the tibia
. Varus angulation of the tibia relative to the femur

Correct Answer & Explanation

. Internal rotation of the tibia relative to the femur

Explanation

During the final 20 degrees of open-chain extension, the tibia must externally rotate relative to the femur to properly articulate the unequal articular surfaces of the femoral condyles. This locks the knee into its most stable position.

Question 7300

Topic: Biology, Genetics & Bone Healing

In the process of bone remodeling, a distinct basophilic line is formed that marks the outer boundary of a newly created osteon. It is rich in osteopontin and deficient in collagen. What is this histological structure called?

. Tidemark
. Cement line (reversal line)
. Howship's lacuna
. Osteoid seam
. Lamina limitans

Correct Answer & Explanation

. Tidemark

Explanation

The cement line (reversal line) marks the outer limit of bone resorption by osteoclasts and the starting point of new bone deposition by osteoblasts. It is characteristically lacking in collagen fibers.

Test Yourself

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

On this Page