1. General Principles & Basic Science MCQs

A 45-year-old mechanic presents with an inability to actively extend his fingers and thumb at the metacarpophalangeal joints. Wrist extension is preserved but exhibits a strong radial deviation. Sensation in the upper extremity is fully intact. Which of the following anatomical structures is the most likely site of neural compression?

A surgeon is performing an L4-L5 posterior instrumented fusion. During the placement of a pedicle screw into the right L4 pedicle, the screw breaches the inferior wall of the pedicle. Which of the following neurologic structures is at greatest risk of direct mechanical injury?

A 28-year-old male is evaluated in the emergency department following a direct blow to the lateral aspect of his shoulder. He has weakness in shoulder abduction and decreased sensation over the lateral deltoid. Through which anatomical space does the injured nerve exit the axilla?

During a lateral closing-wedge high tibial osteotomy, a retractor is carefully placed posterior to the proximal tibia to protect the neurovascular structures. Which of the following vessels is at greatest risk of injury if this retractor is incorrectly positioned directly posterior to the interosseous membrane?

A 30-year-old man sustains a penetrating stab wound to the axilla. Physical examination demonstrates profound weakness in elbow flexion and decreased sensation along the lateral aspect of the forearm. From which portion of the brachial plexus does the injured nerve originate?

An orthopaedic surgeon uses the Smith-Petersen (anterior) approach for a pelvic osteotomy. This approach exploits an internervous plane between the sartorius and the tensor fasciae latae. Which of the following nerves innervates the sartorius?

A lateral transpsoas approach (LLIF) is utilized for interbody fusion at L4-L5. Postoperatively, the patient experiences quadriceps weakness and anterior thigh numbness. Which structure within the psoas major muscle was most likely injured?

A surgeon utilizes the Smith-Petersen (direct anterior) approach for a total hip arthroplasty. To prevent denervation of the surrounding musculature, the dissection utilizes a true internervous plane. Which two nerves supply the muscles defining this superficial interval?

A patient sustains a traumatic knee dislocation and undergoes immediate reduction. Vascular evaluation is required due to the high risk of popliteal artery injury. Between which two distinct anatomical structures is the popliteal artery firmly tethered, making it susceptible to shear stress?

A patient sustains a spiral fracture of the distal third of the humerus (Holstein-Lewis fracture). They present with wrist drop and loss of finger extension. The nerve involved is at greatest risk of tethering as it passes through which anatomical structure?

Following a traumatic anterior shoulder dislocation, a patient complains of numbness over the lateral aspect of the shoulder. The injured nerve exits the axilla through the quadrangular space. Which of the following muscles forms the inferior border of this space?

Piriformis syndrome occurs due to compression of the sciatic nerve by the piriformis muscle. In the most common anatomical configuration, what is the relationship of the sciatic nerve to the piriformis muscle as it exits the greater sciatic foramen?

A 19-year-old female skier sustains a non-contact pivoting injury to her right knee, presenting with an immediate hemarthrosis. An acute ACL rupture is confirmed on MRI. What is the most common associated meniscal injury seen acutely in this specific setting?

A 24-year-old male undergoes a Latarjet procedure for recurrent anterior shoulder instability with severe glenoid bone loss. Postoperatively, he demonstrates profound weakness in elbow flexion and decreased sensation over the lateral aspect of his forearm. Which nerve was most likely injured during the surgical approach?

A 40-year-old male suffers a valgus knee injury. An MRI is obtained, revealing a distal avulsion of the superficial medial collateral ligament (MCL). The torn distal end is flipped superficial to the pes anserinus tendons (a Stener-like lesion). What is the recommended management?

When comparing the tibial inlay technique to the transtibial technique for Posterior Cruciate Ligament (PCL) reconstruction, what is the primary biomechanical advantage of the tibial inlay approach?

A 30-year-old weightlifter sustains a pectoralis major rupture while performing a heavy bench press. Regarding the anatomy of the pectoralis major tendon, where does the sternocostal head typically insert on the humerus relative to the clavicular head?

A 45-year-old marathon runner feels a sharp pain in the posteromedial knee.

MRI demonstrates a complete radial tear of the medial meniscus posterior root. If left untreated, the biomechanical consequences are most similar to which of the following?

The anterolateral ligament (ALL) of the knee originates posterior and proximal to the lateral epicondyle and inserts on the proximal tibia midway between Gerdy's tubercle and the fibular head. What is its primary biomechanical role?

A 28-year-old competitive weightlifter feels a sudden pop and tearing sensation in his anterior chest while bench pressing. Examination reveals ecchymosis and loss of the normal axillary fold contour. If surgical repair is performed, the ruptured tendon should be reattached to which anatomical landmark?