Orthopedic Anatomy MCQs (Set 1): Spine, Upper & Lower Limb | AAOS ABOS 2002 Review

A patient has right shoulder pain. Figure 1a shows a gadolinium-enhanced transverse MRI scan at the level of the coracoid. Figure 1b shows an arthroscopic view of the anterior structures from a posterior portal. These images reveal which of the following findings?

What muscle attaches to the site shown by the arrow in Figure 2?

Figures 3a and 3b show the inversion stress radiographs of a patient's ankle. What is the most likely ligament injury pattern?

Posterior sternoclavicular dislocations are most commonly associated with which of the following complications?

An AP radiograph of the pelvis is shown in Figure 4. What muscle attaches to the avulsed fragment of bone identified by the arrow?

A patient with an acromioclavicular dislocation has a very prominent distal clavicle. Examination reveals that the deformity increases rather than reduces with an isometric shoulder shrug. Which of the following structures is most likely intact?

Figures 5a and 5b show axial and coronal MRI images of the left ankle of a patient with lateral ankle pain. What is the most likely diagnosis?

Which of the following anatomic structures is often difficult to visualize during elbow arthroscopy?

The quadrilateral space in the shoulder contains which of the following structures?

Based on the MRI scan shown in Figure 6, the abnormal signal is seen in what carpal bone?

The recurrent motor branch of the median nerve innervates which of the following muscles?

Which of the following nerves innervates the muscle that originates from the middle third of the dorsal surface of the lateral border of the scapula, as shown in Figure 7?

Based on the MR arthrogram of the elbow shown in Figure 8, which of the following structures is torn?

A 26-year-old man has recurrent right knee pain. Figures 9a and 9b show consecutive sagittal T2-weighted MRI scans, and Figure 9c shows a coronal T1-weighted MRI scan. What is the most likely diagnosis?

The gluteus maximus is innervated by which of the following nerves?

The dorsal (Thompson) approach to the proximal forearm uses which of the following intermuscular intervals?

A 45-year-old man who smokes reports the rapid onset of color changes and coolness in the fingers. Examination shows an abnormal Allen test. Plain radiographs of the hand and wrist are normal. Which of the following studies will best aid in diagnosis?

A purulent flexor tenosynovitis of the thumb may communicate with the small finger flexor through which of the following structures?

Which of the following nerves travels with the deep palmar arch?

Figures 10a through 10c show the plain radiograph and MRI scans of a 41-year-old man who has right hip pain. What is the most likely diagnosis?

Figure 11 shows the anatomic dissection of the medial side of the knee joint after removal of the superficial fascia. The arrow is pointing to what structure?

Figure 12 shows a lateral radiograph of the elbow. What is the most likely diagnosis?

Which of the following nerves is most likely responsible for symptoms associated with plantar fasciitis?

A 16-year-old cheerleader reports an ache in the right shoulder and arm that is worse after activity. She denies any history of acute trauma. Examination reveals a positive sulcus sign and an AP glide test with a posterior and anterior apprehension sign. To confirm a diagnosis of multidirectional instability, which of the following imaging studies is most appropriate?

Which of the following findings is seen in the chest radiograph shown in Figure 13?

In the standard anterior Smith-Robinson approach to the cervical spine, the dissection interval relies on an internervous plane. Which of the following structures constitutes the medial boundary of this plane?

Figure 10 represents a cross-section of the shoulder. Which nerve exits the axilla posteriorly through the quadrilateral space?

The blood supply to the adult femoral head is predominantly provided by the lateral epiphyseal artery. This artery is a direct terminal branch of which of the following vessels?

When placing lumbar pedicle screws, accurate identification of the starting point is critical to avoid nerve root injury. The medial border of the lumbar pedicle correlates with which anatomic landmark on the posterior elements?

During a lateral approach to the proximal tibia and knee, the surgeon isolates a nerve that passes posterior to the biceps femoris tendon and wraps around the fibular neck. Injury to this nerve leads to severe weakness in which of the following movements?

Based on a normal cross-section of the forearm (as seen in Figure 6), the anterior interosseous nerve (AIN) courses distally along the interosseous membrane. Which of the following muscles is NOT innervated by the AIN?

In the standard posterolateral approach to the ankle for fixation of a posterior malleolus fracture, the internervous plane lies between the flexor hallucis longus and which of the following structures?

During a sacral laminectomy or decompression, the surgeon must be acutely aware of the termination of the dural sac. In the normal adult spine, the dural sac typically terminates at which vertebral level?

A patient presents with a deep penetrating injury to the palm and demonstrates an inability to forcefully cross the index and middle fingers. Which of the following nerves is most likely injured?

Figure 4 demonstrates a cross-section of the posterior thigh. The sciatic nerve generally divides into the tibial and common peroneal nerves proximally. Which muscle is exclusively innervated by the common peroneal division of the sciatic nerve?

During the Kocher approach to the radial head, the surgeon dissects through an internervous plane. This plane lies between the extensor carpi ulnaris and which other muscle?

The ilioinguinal approach is commonly used for anterior column acetabular fractures. Which nerve is at greatest risk of iatrogenic injury during the mobilization of the structures in the "middle window"?

When approaching the thoracic spine via a costotransversectomy, the artery of Adamkiewicz must be considered to avoid spinal cord ischemia. This critical vessel typically enters the spinal canal through an intervertebral foramen at which levels?

The deep motor branch of the ulnar nerve passes between the pisiform and the hook of the hamate in Guyon's canal. Which of the following structures forms the roof of this canal?

During open reduction and internal fixation of a calcaneus fracture via an extensile lateral approach, the surgeon elevates a full-thickness subperiosteal flap. Which nerve is at the highest risk of transection in the proximal vertical limb of the incision?

A patient exhibits marked lateral winging of the scapula following a lymph node biopsy in the posterior triangle of the neck. The patient struggles to abduct the shoulder past 90 degrees. Which nerve was most likely injured?

The vertebral artery is a critical vascular structure that ascends through the cervical spine. In the majority of the population, at which cervical vertebral level does the vertebral artery typically first enter the transverse foramen?

When evaluating injuries to the posterolateral corner of the knee, understanding the intricate capsuloligamentous anatomy is paramount. Which specific structure directly attaches the fibular head to the lateral meniscus?

During a Bankart repair, the surgeon must address the essential capsulolabral lesion. Which of the following structures serves as the primary static restraint to anterior translation of the humeral head when the shoulder is positioned in 90 degrees of abduction and maximal external rotation?

During a deltoid-splitting lateral approach to the proximal humerus, the axillary nerve is at significant risk of iatrogenic injury. What is the average anatomical distance from the lateral tip of the acromion to the axillary nerve in an adult?

A patient presents with a severe traction injury to the brachial plexus after a motorcycle collision. Physical examination reveals miosis, ptosis, and anhidrosis on the ipsilateral side. Avulsion of which nerve root is most likely responsible for these specific findings?

When decompressing Guyon's canal for ulnar nerve entrapment, a surgeon must be intimately aware of its boundaries. Which of the following structures forms the floor of Guyon's canal?

Compression of the posterior interosseous nerve (PIN) most commonly occurs at the Arcade of Frohse. This arcade is formed by the proximal aponeurotic edge of which muscle?

During anterior cervical spine surgery extending to the lower cervical segments, the vertebral artery is at risk. In the vast majority of the population, the vertebral artery enters the transverse foramen at which cervical level?

To properly place a lumbar pedicle screw, the surgeon must identify the correct starting point to avoid neurological injury. Anatomically, the standard starting point is defined by the intersection of the:

When performing a posterior approach to the hip (Kocher-Langenbeck), the medial femoral circumflex artery (MFCA) is at risk. The main ascending branch of the MFCA consistently runs deep to which muscle?

The posterolateral corner (PLC) of the knee provides critical rotatory stability. Which structure is the primary restraint to external rotation of the tibia at 30 degrees of knee flexion?

During a posterolateral approach to the ankle for fixation of a posterior malleolus fracture, the sural nerve must be protected. The sural nerve typically courses in close proximity to which structure in the distal leg?

During an ilioinguinal approach for an anterior column acetabular fracture, severe hemorrhage is encountered upon dissection over the superior pubic ramus. This bleeding is most likely from the corona mortis, an anastomosis between the:

The superficial radial nerve is at risk during the distal extent of the Henry approach to the forearm. Anatomically, it emerges from beneath which muscle in the distal third of the forearm to become subcutaneous?

A patient sustains a deep laceration to the palm, severing the deep branch of the ulnar nerve. Which of the following functional deficits is most likely to be observed?

When placing iliosacral screws for pelvic ring injuries, the surgeon must remain within the osseous safe zone of the sacral ala. The anterior limit of this safe zone in S1 is defined by the risk of injury to which structure?

A 25-year-old male develops acute compartment syndrome of the deep posterior compartment of the leg after a tibial fracture. Which of the following neurovascular structures is contained within this compartment?

During a medial subvastus approach to the distal femur, the adductor canal (Hunter's canal) is visualized. Which of the following nerves runs within the adductor canal?

A 28-year-old overhead athlete presents with isolated weakness in external rotation of the shoulder. An MRI reveals a paralabral cyst in the spinoglenoid notch. Which muscle is predominantly denervated?

The adult spinal cord typically terminates distally as the conus medullaris. In the majority of adults, this termination occurs at which vertebral body level?

The Master Knot of Henry is an important anatomical landmark in the plantar aspect of the midfoot. It refers to the intersection where the:

During a posterior cervical foraminotomy at C5-C6, the surgeon is mindful of the boundaries of the intervertebral foramen. The vertebral artery is typically located in which relation to the exiting C6 nerve root?

A 28-year-old volleyball player presents with insidious onset of vague posterior shoulder pain and profound weakness in external rotation, with preserved abduction. At what anatomical site is the injured nerve most likely compressed?

Figure 4 shows an anatomic dissection of the lateral aspect of the knee.

The primary restraint to external rotation of the tibia at 30 degrees of knee flexion inserts on which of the following structures?

When placing a pedicle screw at the L4 level, the optimal starting point is at the intersection of the pars interarticularis, the superior articular facet, and the transverse process. What nerve root is most at risk if the screw breaches the pedicle inferiorly?

A patient sustains a deep laceration over the volar aspect of the index finger metacarpophalangeal joint. The first lumbrical muscle is injured. What is its precise origin and innervation?

During a Kocher-Langenbeck approach to the hip, the surgeon must protect the primary blood supply to the femoral head. Which structure serves as a critical landmark to protect the deep branch of the medial femoral circumflex artery?

Figure 10 demonstrates standard portals for ankle arthroscopy.

When establishing the posterolateral portal, the sural nerve is at risk. What is its normal anatomical relationship to the portal site?

When placing Sacral Alar Iliac (SAI) screws for spinopelvic fixation, the trajectory crosses the SI joint. Which anterior structure is most at risk with an overly anterior and superior trajectory breach of the sacral ala?

A 45-year-old mechanic complains of chronic, aching pain in the proximal lateral forearm without overt motor weakness, exacerbated by resisted forearm supination. The most common site of compression for the involved nerve is the:

Figure 13 displays a cross-section of the midfoot.

The true Lisfranc ligament connects which two osseous structures?

During a deltopectoral approach for a proximal humerus fracture, identifying and protecting the axillary nerve is paramount. At what distance distal to the lateral acromial edge does the main trunk of the axillary nerve typically cross the humerus?

A spine surgeon evaluates a pre-operative CT scan for a T8 burst fracture. Compared to the lumbar spine, which of the following is true regarding the anatomy of mid-thoracic pedicles?

Figure 19 highlights an arthroscopic view of a meniscus.

Which of the following describes a key anatomical difference between the medial and lateral menisci?

A 21-year-old collegiate baseball pitcher is diagnosed with an ulnar collateral ligament (UCL) tear. The anterior bundle of the UCL inserts on the sublime tubercle. Which specific portion of the anterior bundle is most taut in extension?

Figure 25 details the anterior thigh musculature.

A patient requires a femoral nerve block. Which of the following accurately describes the position of the femoral nerve within the femoral triangle?

In atlas (C1) lateral mass screw fixation, the surgeon must avoid both vascular structures. Which anatomic trajectory and starting point minimizes the risk to both the vertebral artery and the internal carotid artery?

A patient complains of ulnar-sided wrist pain after a fall. MRI shows a tear of the foveal attachment of the Triangular Fibrocartilage Complex (TFCC). This specific attachment is critical for:

A patient develops an isolated acute compartment syndrome of the lateral compartment of the lower leg. Which of the following physical exam findings is most expected?

Figure 30 demonstrates the osseous landmarks of the scapula.

The coracoacromial ligament attaches to the acromion and the coracoid process. Which variation of the acromion morphology is most strongly associated with full-thickness rotator cuff tears?

During an anterior intrapelvic (modified Stoppa) approach for an acetabular fracture, significant hemorrhage occurs near the superior pubic ramus. The most likely source is the corona mortis, which represents an anastomosis between:

A surgeon is performing a lateral transpsoas approach to the L4-L5 disc space. To avoid injury to the lumbar plexus, the retractor should be placed carefully, as the nerve responsible for quadriceps function is located in which region of the psoas muscle at this level?

During a standard deltopectoral approach to the shoulder, the cephalic vein is identified in the interval. To optimally preserve its venous drainage, what is the standard recommended handling of this structure?

A 24-year-old athlete requires surgical reconstruction for a posterolateral corner knee injury. Identifying and protecting the common peroneal nerve is critical. Which of the following describes its most reliable anatomical position in the posterolateral knee?

An anterior cervical discectomy and fusion (ACDF) is planned at the C6-C7 level. A right-sided approach is historically considered to have a higher risk of recurrent laryngeal nerve (RLN) injury compared to a left-sided approach due to which anatomical variant?

A patient presents with weakness in flexing the interphalangeal joint of the thumb and the distal interphalangeal joint of the index finger. Which anomalous structure is most commonly responsible for compressing the nerve involved?

During a Kocher-Langenbeck (posterior) approach to the acetabulum, identifying the sciatic nerve is essential. The nerve classically exits the greater sciatic foramen in what relation to the short external rotators?

The deep palmar arch of the hand provides significant collateral blood flow. It is primarily formed by the anastomosis of which of the following vessels?

When performing an anterior approach for a thoracolumbar corpectomy, the surgeon must be aware of the artery of Adamkiewicz to prevent anterior spinal cord syndrome. This vessel most commonly arises from the aorta at which levels?

An anterolateral approach to the distal tibia is used for pilon fracture fixation. The superficial peroneal nerve is at risk in this exposure. Where does this nerve predictably pierce the deep fascia to become subcutaneous?

A patient sustains an injury resulting in medial winging of the scapula. Which nerve is injured, and what are its correct nerve root origins?

A surgeon is performing a midfoot reconstruction and exploring the plantar aspect of the foot. The Master Knot of Henry is identified. This anatomical landmark represents the intersection of which two structures?

During placement of an S1 iliosacral screw for a displaced sacral fracture, an anterior extraosseous screw trajectory risks injuring which neural structure passing over the sacral ala?

When utilizing a dorsal approach to the wrist, Lister's tubercle is a key osseous landmark. It serves as a mechanical pulley for which tendon?