Gross Anatomy

The teres major is not part of the rotator cuff. The rotator cuff muscles are supraspinatus, infraspinatus, teres minor, and subscapularis. Teres major assists adduction and medial rotation of the humerus but it does not contribute to glenohumeral joint stabilization like the cuff muscles do.

The unhappy triad classically includes the anterior cruciate ligament, the medial collateral ligament, and the medial meniscus. The posterior cruciate ligament is not part of this triad. The injury usually results from a valgus stress with external rotation to the knee.

The femoral triangle contains the femoral nerve, artery, and vein, followed by empty space and lymphatics. A ligament is not a content of the triangle. The inguinal ligament forms the superior boundary of the triangle rather than being inside it.

The carotid sheath contains the common and internal carotid artery, the internal jugular vein, and the vagus nerve which is cranial nerve X. Cranial nerve IX lies outside the sheath. For this reason cranial nerve IX is not a component of the carotid sheath.

The dermatome at the level of the inguinal ligament is L1. The T10 dermatome corresponds to the umbilicus, L3 is near the anterior knee, and L5 is on the dorsum of the foot and great toe. Therefore L1 is the correct landmark match.

The deltoid muscle is innervated by the axillary nerve.

The radial nerve primarily supplies the posterior compartment of the arm and forearm, cranial nerve XI supplies the trapezius and sternocleidomastoid, and the subscapular nerves supply subscapularis and teres major.

Axillary is the only choice that innervates the deltoid.

Wrist extension is controlled primarily by the radial nerve. The median and ulnar nerves mainly supply wrist and finger flexors and intrinsic hand muscles. The tibial nerve supplies the posterior compartment of the leg and the plantar foot and does not control wrist extensors.

The adductor pollicis is innervated by the deep branch of the ulnar nerve. Most thenar muscles are supplied by the median nerve, but adductor pollicis is a notable exception. The radial and tibial nerves do not supply this muscle.

The left anterior descending artery is the most common site of coronary artery stenosis, especially in its proximal segment. The LAD supplies the anterior wall and most of the interventricular septum which makes narrowing here particularly clinically significant.

The left main and right coronary arteries are proximal trunks and the posterior descending artery is less commonly the primary site of disease.

The tibial nerve derives from L4 through S3 and is therefore not directly linked to the L2 and L3 spinal levels. In contrast, the femoral nerve and the obturator nerve both include fibers from L2 and L3. This makes the tibial nerve the correct choice.

The inferior orbital fissure transmits the infraorbital nerve which is a continuation of the maxillary division of the trigeminal nerve and the accompanying infraorbital vessels.

The stylomastoid foramen transmits the facial nerve as it exits the skull, the foramen ovale transmits the mandibular division of the trigeminal nerve, and the carotid canal transmits the internal carotid artery.

Although the maxillary nerve proper passes through the foramen rotundum, its continuation reaches the orbit via the inferior orbital fissure.

The stylomastoid foramen transmits the facial nerve as it exits the temporal bone, along with the stylomastoid artery. The inferior orbital fissure carries the infraorbital nerve and vessels, the foramen ovale carries the mandibular division of the trigeminal nerve, and the carotid canal carries the internal carotid artery. Therefore the stylomastoid foramen is the correct answer.

The carotid canal carries the internal carotid artery along with the internal carotid plexus of sympathetic fibers. The foramen ovale carries the mandibular division of the trigeminal nerve, the foramen rotundum carries the maxillary division, and the condylar canal transmits emissary veins. Only the carotid canal contains the internal carotid artery.

The most common site of lumbar disc herniation is L5 to S1 with L4 to L5 being the next most common level. Herniation at L5 to S1 often compresses the S1 nerve root and can cause loss of the ankle reflex and pain down the posterior leg. Cervical and thoracolumbar junction levels are less commonly affected.

The deltoid ligament is located at the medial ankle and is not found in the knee. The patellar ligament, the oblique popliteal ligament, and the arcuate popliteal ligament are all ligaments of the knee. Therefore the deltoid ligament is the correct choice.

The teres minor muscle is innervated by the axillary nerve. The subscapular nerves supply the subscapularis and teres major, and the suprascapular nerve supplies the supraspinatus and infraspinatus. The pectoral nerves supply the pectoralis major and minor muscles and do not innervate teres minor.

The pronator teres muscle is innervated by the median nerve. The radial nerve supplies the extensor compartment of the forearm, the musculocutaneous nerve supplies the anterior compartment of the arm, and the ulnar nerve supplies the flexor carpi ulnaris and part of the flexor digitorum profundus along with many intrinsic hand muscles. Only the median nerve innervates pronator teres.

The pudendal nerve supplies the muscles and skin of the perineum. The sciatic nerve supplies the posterior thigh and most of the leg and foot via its branches, the femoral nerve supplies the anterior thigh, and the tibial nerve supplies the posterior compartment of the leg and the plantar foot. None of these alternatives primarily serve the perineum.

The superior oblique muscle depresses, abducts, and intorts the eye which produces movement downward and away from the midline. The inferior rectus depresses and adducts the eye, and the inferior oblique elevates and abducts the eye. The superior rectus elevates and adducts the eye and does not match the described movement.

The superior rectus elevates and adducts the eye which moves the eye upward and toward the midline, and it also intorts the globe. The inferior oblique elevates but abducts the eye which moves it upward and away from the midline. The superior oblique depresses the eye rather than elevating it.