Anatomy Final Pt 2

The radial nerve innervates the muscles responsible for wrist extension. In this case, the severe damage to the radial nerve due to the fracture of the midshaft of the humerus would result in the loss of function of these muscles. This loss of wrist extension leads to a condition called wrist drop, where the wrist cannot be extended and hangs in a flexed position. Therefore, the most likely result from this accident would be the loss of wrist extension leading to wrist drop.

The correct answer is Facia. The fibrous sheets or bands that cover the body under the skin and invest the muscles are called fascia. If a person has a laceration in this area, it is most likely that the fascia would be injured.

When a 14-year-old boy falls on his outstretched hand and fractures his scaphoid bone, the fracture is most likely accompanied by a rupture of the radial artery. The scaphoid bone is located in the wrist, and the radial artery runs along the thumb side of the forearm and wrist. A fracture in this area can cause damage to the radial artery, leading to bleeding and potential complications.

If the lateral (fibular) collateral ligament is torn by this fracture, it would result in a loss of stability on the lateral side of the knee joint. This would lead to abnormal passive adduction of the extended leg, where the leg moves inward towards the midline of the body. This occurs because the torn ligament can no longer provide the necessary support to prevent this inward movement.

The most likely diagnosis for a 21-year-old patient with a lesion of the upper trunk of the brachial plexus (Erb-Duchenne paralysis) is an arm tending to lie in medial rotation. This is because the upper trunk of the brachial plexus innervates the muscles responsible for external rotation of the arm, and when this is affected, the unopposed action of the internal rotators causes the arm to lie in a medial rotation position.

The superior thoracic artery would maintain normal blood flow if the thoracoacromial trunk is ligated during surgery. The thoracoacromial trunk is a major branch of the axillary artery, and it gives rise to several arteries including the acromial, pectoral, clavicular, and deltoid arteries. Ligation of the thoracoacromial trunk would cut off blood supply to these branches, but the superior thoracic artery, which is a separate branch of the axillary artery, would still provide blood flow to the area.

The humerus is located in the upper arm, and the nerves that are most closely related to this bone are the radial and axillary nerves. Therefore, a fracture of the upper portion of the humerus is most likely to injure these nerves.

The physician would most likely examine the Atlantoaxial joint. The patient's complaint of severe pain when turning his neck suggests a problem with the joint responsible for rotation between the atlas (C1) and axis (C2) vertebrae, which is the Atlantoaxial joint. This joint allows for the majority of rotational movement in the neck, and dysfunction or injury in this area can cause severe pain and limited range of motion.

Paralysis of the pectoralis minor, which is responsible for drawing the scapula forward and downward, is most likely caused by a fracture of the coracoid process. The coracoid process is a bony projection of the scapula that serves as an attachment site for the pectoralis minor muscle. If the coracoid process is fractured, it can disrupt the attachment of the pectoralis minor, leading to paralysis of the muscle and the inability to draw the scapula forward and downward.

The patient's inability to flex her proximal interphalangeal joints suggests a paralysis of the flexor digitorum superficialis muscle. This muscle is responsible for flexing the middle phalanges of the fingers, which allows for flexion of the proximal interphalangeal joints. The other muscles listed, such as the palmar interossei, dorsal interossei, flexor digitorum profundus, and lumbricals, are not directly involved in flexing the proximal interphalangeal joints.

The deep peroneal nerve is responsible for dorsiflexion of the foot, which is the ability to invert the foot. The tibial nerve is responsible for plantarflexion of the foot. In this case, the woman is unable to invert her foot, suggesting that the deep peroneal nerve is injured. The tibial nerve may also be injured, as it is involved in the same movement.

The ulnar artery and ulnar nerve are the structures that enter the palm superficial to the flexor retinaculum. Injuring the wrist on broken glass can potentially damage these structures. The other options mentioned do not enter the palm superficial to the flexor retinaculum and therefore would not be affected in this scenario.

The superior gluteal nerve is responsible for innervating the gluteus medius, gluteus minimus, and tensor fasciae latae muscles. These muscles help to stabilize the pelvis during walking and maintain a level pelvis. If the superior gluteal nerve is damaged, the gluteus medius and minimus muscles will be weakened or paralyzed, causing the pelvis to fall toward the unaffected side during walking. This results in a waddling gait, as described in the question.

If the acetabulum is fractured at its posterosuperior margin by dislocation of the hip joint, the bone that could be involved is the ilium. The ilium is one of the three bones that make up the acetabulum, along with the ischium and pubis. A fracture in this region can occur due to a traumatic injury or dislocation of the hip joint, which can result in damage to the ilium bone. The other options, including the pubis, ischium, sacrum, and head of the femur, are not directly involved in the formation of the acetabulum and are less likely to be affected by this specific type of fracture.

The superior gluteal artery maintains blood flow in the upper thigh if all of the arteries that are part of the cruciate anastomosis are ligated.

The ulnar nerve is responsible for providing sensory innervation to the medial third of the hand and the medial one and one-half fingers. This nerve is commonly referred to as the "funny bone" nerve because it can be easily irritated or injured, leading to symptoms such as sensory loss in the described areas.

The teres major muscle tendon is intact and has normal function in a patient with a torn rotator cuff of the shoulder joint as a result of an automobile accident. This is because the teres major muscle is not part of the rotator cuff muscles. The rotator cuff muscles include the supraspinatus, subscapularis, infraspinatus, and teres minor.

The pulmonary veins carry oxygenated blood from the lungs back to the heart. In a healthy individual, these veins should not have any leakage of blood. Therefore, if a leakage of blood is found in a patient, it suggests that the pulmonary veins are damaged. This is the most likely vessel to be damaged in this scenario.

The obturator nerve innervates the muscles of the medial compartment of the thigh, which includes the adductor longus muscle. When the obturator nerve is transected, it leads to complete paralysis of the adductor longus muscle. Therefore, the correct answer is Adductor longus.

The patient's symptoms of sensory loss on adjacent sides of the great and second toes and impaired dorsiflexion of the foot indicate damage to the deep peroneal nerve. The deep peroneal nerve innervates the muscles that control dorsiflexion of the foot and also provides sensory innervation to the adjacent sides of the great and second toes.

An injury to the leg of a golfer resulting in the loss of the ability to invert the foot suggests damage to the tibialis posterior muscle. The tibialis posterior muscle is responsible for inversion of the foot, which is the movement of turning the sole of the foot inward. Paralysis of this muscle would cause the inability to perform this movement, leading to the observed symptom.

Anterior tibial compartment syndrome would occur from this fracture.

The woman experiences weakness when abducting and medially rotating the thigh after the accident. The gluteus minimus muscle is most likely damaged because it is responsible for these movements.

The intercostobrachial nerve is responsible for providing sensory fibers to the lateral aspect of the arm. Therefore, if this nerve is injured, it would result in a loss of tactile sensation on the lateral aspect of the arm. The other options are not related to the intercostobrachial nerve and are not consistent with the described lesion.

The correct answer is Latissimus Dorsi. The patient's inability to adduct her arm suggests paralysis of the Latissimus Dorsi muscle. The Latissimus Dorsi muscle is responsible for adducting and extending the arm at the shoulder joint. If this muscle is paralyzed, it would result in the inability to bring the arm towards the midline of the body.

The most likely structure to be damaged in this scenario is the median nerve. The question mentions a stab wound to the most medial side of the proximal portion of the cubital fossa. The cubital fossa is located on the anterior aspect of the elbow, and the median nerve runs through this region. Therefore, a stab wound in this area could potentially injure the median nerve.

Fracture of the neck of the femur can lead to avascular necrosis of the femoral head, which is caused by a lack of blood supply. The blood supply to the femoral head is mainly provided by the medial femoral circumflex artery. When the neck of the femur is fractured, it can disrupt the blood flow through this artery, resulting in avascular necrosis. Therefore, the fracture of the neck of the femur can lead to avascular necrosis of the femoral head due to the lack of blood supply from the medial femoral circumflex artery.

The great saphenous vein remains intact because the infection and damage were found in the adductor canal, which does not involve the great saphenous vein. The adductor canal is located in the thigh and contains the femoral artery, femoral vein, saphenous nerve, and nerve to the vastus medialis. However, the great saphenous vein is not enclosed within the adductor canal and therefore remains unaffected.

The two medial lumbrical muscles are most likely to be paralyzed in a 27-year-old man with cubital tunnel syndrome. Cubital tunnel syndrome is caused by compression or irritation of the ulnar nerve at the elbow, which can result in numbness and tingling in the ring and little finger and the back and sides of the hand. The ulnar nerve innervates the two medial lumbrical muscles, which are responsible for flexing the metacarpophalangeal joints and extending the interphalangeal joints of the ring and little fingers. Therefore, damage to the ulnar nerve in the cubital tunnel can lead to paralysis of these muscles.

The correct answer is Vastus lateralis. The question states that the muscle originates from the femur and contributes directly to the stability of the knee joint. The Vastus lateralis muscle meets both of these criteria. It originates from the femur and is one of the four muscles that make up the quadriceps muscle group, which is responsible for extending the knee joint and providing stability.

The common peroneal nerve is most likely damaged in this scenario because it innervates the muscles in the anterior compartment of the leg, which includes the muscles that dorsiflex the foot and extend the toes. Fractures of the head and neck of the fibula can result in compression or stretching of the common peroneal nerve, leading to motor and sensory deficits in the lower leg and foot. The other nerves listed do not innervate the muscles in the anterior compartment of the leg and are less likely to be affected by this specific injury.

The correct answer is Quadriceps femoris. The quadriceps femoris is responsible for extending the leg at the knee joint. If this muscle is paralyzed, the person would be unable to extend their leg at the knee joint, which aligns with the woman's complaint after slipping and falling.

The gluteus maximus is responsible for extending the thigh and rotating it laterally. If this muscle is paralyzed, it would result in weakness in these movements. Therefore, the correct answer is Gluteus maximus.

The ulnar nerve is responsible for innervating the muscles that control the movements of the fingers and hand. It specifically controls the muscles that allow for the adduction and abduction of the fingers. In this scenario, the man is unable to hold the typing paper between his index and middle fingers, indicating a loss of adduction function. This suggests that the ulnar nerve, which controls the adductor muscles, is likely injured.

The rupture of the ligamentum teres capitis femoris may lead to damage to the obturator artery. The obturator artery is a branch of the internal iliac artery and supplies blood to the muscles and structures in the medial compartment of the thigh, including the hip joint. Damage to this artery can result in compromised blood supply to the affected area, leading to ischemia and potential complications.

The correct answer is Suprascapular and axillary. The suprascapular nerve innervates the supraspinatus and infraspinatus muscles, which are responsible for shoulder abduction. The axillary nerve innervates the deltoid muscle, which also contributes to shoulder abduction. Damage to both of these nerves would result in the inability to abduct the arm. Musculocutaneous and median nerves innervate muscles of the forearm, not the shoulder. Axillary and radial nerves innervate different muscles in the arm and do not control shoulder abduction. Median and ulnar nerves innervate muscles of the hand, not the shoulder.

The anterior tibial artery is likely to compress and cause ischemia because it is located in the front of the leg and supplies blood to the extensor muscles. The bruise and damage to the extensor muscles can lead to swelling and compression of the artery, restricting blood flow and causing ischemia.

The ulnar and radial nerves were likely damaged because the woman is unable to move the metacarpophalangeal joint of her ring finger. The ulnar nerve innervates the muscles responsible for flexing the ring finger, while the radial nerve innervates the muscles responsible for extending the finger. Damage to both nerves would result in the inability to move the joint.

The correct answer is the Dorsal scapular artery. The patient is in fair condition because there is vascular anastomosis around the shoulder. The Dorsal scapular artery is a direct branch of the subclavian artery and is involved in the anastomosis. This artery helps to provide a collateral blood supply to the shoulder region, allowing for adequate blood flow even if there is bleeding from the shoulder due to a knife wound.

The radial nerve innervates the muscles responsible for forearm supination, while the musculocutaneous nerve innervates the muscles responsible for elbow flexion. Therefore, damage to both the radial and musculocutaneous nerves would result in the inability to supinate the forearm.

If the brachial artery is ligated at its origin, the blood supply to the profunda brachii artery would be provided by the posterior humeral circumflex artery.

After injury to the nerve mentioned, the Extensor hallucis longus muscle could be paralyzed.

The infection in the ulnar bursa can lead to necrosis of the tendon of the flexor digitorum profundus. This is because the flexor digitorum profundus tendon runs through the ulnar bursa, and an infection in the bursa can spread to the tendon, causing tissue death (necrosis).

The fracture mentioned in the question could potentially damage the anterior tibial artery.

The correct answer is the lesser saphenous vein. In this scenario, the superficial vein that is penetrated is the one that terminates in the popliteal vein. Among the options provided, the only vein that terminates in the popliteal vein is the lesser saphenous vein. Therefore, bleeding would occur from the lesser saphenous vein.

The lateral circumflex femoral artery is the correct answer because it is not affected by the blood clot in the popliteal artery. It is a branch of the deep femoral artery and supplies blood to the lateral thigh. Since it is not dependent on the popliteal artery for blood flow, it can still provide blood to the foot despite the clot. The other arteries listed, such as the anterior tibial, posterior tibial, peroneal, and superior medial genicular arteries, are all branches of the popliteal artery and would be affected by the clot, limiting blood flow to the foot.

The saphenous branch of the descending genicular artery is most likely spared during knee surgery. The other arteries mentioned, such as the lateral superior genicular artery, medial inferior genicular artery, descending branch of the lateral femoral circumflex artery, and anterior tibial recurrent artery, are all involved in the anastomosis around the knee joint and would therefore be ligated during surgery.