Orthopedic Anatomy 2026 MCQs: Board Review Questions & Answers (Part 1)

During a retroperitoneal approach to the L4-5 disk, what structure must be ligated to safely mobilize the common iliac vessels toward the midline from laterally and gain exposure?

The injection shown in Figures 1a and 1b would most benefit a patient who reports which of the following symptoms?

In Figure 2, which of the following structures is the primary stabilizer in preventing valgus instability of the elbow?

When performing surgical excision of the lesion shown in the MRI scan in Figure 3, what nerve is most likely at risk?

Figure 4a shows the radiograph of a 20-year-old man who has an injury to the right shoulder. Figure 4b shows an arthroscopic view (posterior portal). The arrow points to a

A 15-year-old girl who swims the breaststroke has had hip pain after training excessively for a national level competition. Based on the MRI scans shown in Figures 5a through 5c, what is the most likely diagnosis?

During placement of an external fixator for a distal radius fracture, the most commonly injured nerve is a branch of which of the following nerves?

Figure 6 shows a sagittal oblique MRI scan. The arrow is pointing to what structure?

An 18-year-old woman sustains a twisting injury of the knee while skiing. Figures 7a and 7b show the radiograph and coronal MRI scan of the knee. In addition to the injury shown, what is the most likely associated injury?

A 42-year-old athletic trainer has a persistent popping sensation about the lateral ankle associated with weakness and pain following a remote injury. Deficiency in what structure directly leads to this pathology?

A 21-year-old man sustains multiple gunshot wounds to his right upper extremity. He can not extend his digits or his thumb but can extend and radially deviate his wrist. An injury to the radial nerve or one of its branches has most likely occurred at which of the following locations?

A woman with a neck and chest tumor has weakness in the biceps and paresthesias in the thumb. Brachioradialis and infraspinatus function are normal. The lesion is affecting which of the following structures?

Figure 8 shows the radiograph of a 76-year-old man who has knee pain and swelling. History reveals that he underwent total knee arthroplasty 18 years ago. What is the most likely diagnosis?

Which of the following radiographic images is best for detecting anterior acetabular deficiency in the dysplastic hip?

Figure 9 shows the AP radiograph of a 65-year-old man who has knee pain and swelling. What is the most likely diagnosis?

If a surgeon inadvertently burrs through the midlateral wall of C5 during a anterior corpectomy, what structure is at greatest risk for injury?

In patients with displaced radial neck fractures treated with open reduction and internal fixation with a plate and screws, the plate must be limited to what surface of the radius to avoid impingement on the proximal ulna?

A 57-year-old man reports right hip pain that has been progressive for the past several months. The pain is exacerbated by weight-bearing activities and improves somewhat with rest. A radiograph is shown in Figure 10a and a coronal T1-weighted MRI scan is shown in Figure 10b. What is the most likely diagnosis?

The arrow in Figure 11 points toward a finding consistent with which of the following?

The attachments of the transverse carpal ligament include which of the following structures?

A 23-year-old woman falls from a bicycle and sustains a right knee injury. Figures 12a through 12d show radiographs and MRI scans of the knee. What is the most likely diagnosis?

A 25-year-old man has a mass on the medial aspect of the left knee. He reports that the mass has been present for several years, but a recent increase in physical activity has resulted in periodic tenderness. Radiographs are shown in Figures 13a and 13b. What is the most likely diagnosis?

A previously asymptomatic 40-year-old man injures his shoulder in a fall. Examination shows that he is unable to lift the hand away from his back while maximally internally rotated. An axial MRI scan of the shoulder is shown in Figure 14. What is the most likely diagnosis?

A patient is treated with volar plating for a distal radius fracture. The CT scan shown in Figure 15 is obtained after union of the fracture because the patient reports ongoing symptoms. The prominent hardware is most likely injuring what tendon?

A 9-year-old child sustains a proximal tibial physeal fracture with a hyperextension mechanism. What structure is at most risk for serious injury?

During the anterior (Henry) approach to the proximal radius, the surgeon must mobilize a specific muscle to protect the posterior interosseous nerve. Supination of the forearm helps move this nerve away from the surgical field. Which muscle envelops the nerve and is carefully retracted?

A surgeon performs a standard anterior (Smith-Petersen) approach to the hip for a pelvic osteotomy. The internervous plane utilized is between muscles innervated by which two nerves?

When performing an extensile lateral approach to the calcaneus for open reduction and internal fixation of a fracture, a "no-touch" technique is strictly employed for the flap. Which of the following structures is most at risk of iatrogenic injury at the proximal and inferior margin of the incision?

A 45-year-old male presents with an inability to actively extend his metacarpophalangeal joints, but wrist extension is preserved with radial deviation. A compressive neuropathy is suspected. The structure most likely responsible for compression is located between which two muscle parts?

A patient sustains a proximal humerus fracture and later demonstrates profound weakness in shoulder abduction and diminished sensation over the lateral aspect of the deltoid. The affected nerve traverses through a space bounded by which of the following structures?

During a posterior approach to the humerus for fracture fixation, the radial nerve is identified. As it courses distally, it pierces the lateral intermuscular septum to enter the anterior compartment of the arm. On average, at what distance proximal to the lateral epicondyle does this transition occur?

A surgeon is performing an anterior (Smith-Petersen) approach to the hip for a core decompression. To safely develop the internervous plane, the initial superficial dissection should proceed between muscles innervated by which two nerves?

When executing a posterior approach to the shoulder to address glenoid pathology, the surgeon splits the deltoid and then develops an internervous plane between the infraspinatus and teres minor. Which nerve provides motor innervation to the teres minor?

A patient is scheduled for open reduction and internal fixation of a displaced intra-articular calcaneus fracture using an extensile lateral approach. The viability of the full-thickness soft tissue flap relies predominantly on which of the following vessels?

During a right-sided anterior approach to the lower cervical spine (C5-C7), a structure that loops from lateral to medial is at risk of iatrogenic injury, potentially leading to vocal cord paralysis. Around which vascular structure does this nerve loop?

In the proximal portion of the volar (Henry) approach to the forearm, the internervous plane is developed between the brachioradialis and the pronator teres. Which critical nerve structure must be identified and protected as it courses deep to the brachioradialis in this region?

During a standard medial parapatellar approach for a total knee arthroplasty, a branch of the saphenous nerve is frequently sacrificed. What is the typical resulting sensory deficit experienced by the patient?

While performing an ilioinguinal approach for a complex anterior column acetabular fracture, massive hemorrhage occurs near the superior pubic ramus. This is most likely due to an inadvertent injury to an arterial anastomosis between which two vascular systems?

An anterolateral approach to the distal tibia is utilized for open reduction and internal fixation of a pilon fracture. During superficial dissection, which nerve is at greatest risk of transection as it crosses the ankle joint?

An anterior approach to the cubital fossa is performed to repair a distal biceps tendon rupture. Proximal dissection is carried out to expose the deep structures. The radial nerve is typically located between which two muscles in the proximal aspect of this exposure?

During an anterior retroperitoneal approach to the L4-L5 intervertebral disc, lateral mobilization of the great vessels is required. To safely retract the common iliac vessels medially, which structure is routinely identified and ligated?

The anterolateral (Watson-Jones) approach to the hip is frequently used for hemiarthroplasty. This approach develops an intermuscular plane between which two muscles?

A standard deltopectoral approach is utilized for a total shoulder arthroplasty. During the superficial dissection, the cephalic vein is identified in the deltopectoral groove. To best preserve venous drainage and minimize bleeding, how should the vein ideally be managed?

A 65-year-old female sustains a severely displaced surgical neck fracture of the proximal humerus. She exhibits weakness in shoulder abduction. The most likely injured nerve exits the axilla through which anatomical space?

During a posterior approach to the knee for a popliteal artery injury, the vascular bundle is traced distally. The popliteal artery transitions into the posterior tibial and anterior tibial arteries as it exits the popliteal fossa by passing deep to the tendinous arch of which muscle?

A surgeon performs an open carpal tunnel release. To avoid iatrogenic injury to the recurrent motor branch of the median nerve, its anatomical variations must be understood. According to the Lanz classification, what is the most common anatomical path of the recurrent motor branch?

A dorsal approach to the wrist is performed for a scaphoid nonunion. The surgeon makes an incision and enters the interval between the 3rd and 4th extensor compartments. Which tendon exclusively occupies the 3rd extensor compartment?

In the anterior intrapelvic (modified Stoppa) approach for acetabular fracture fixation, dissection proceeds along the pelvic brim. Which nerve lies directly on the anterior surface of the obturator internus muscle and is highly vulnerable during placement of sub-pelvic retractors?

A lateral approach to the distal femur is utilized for plating a supracondylar femur fracture. As the vastus lateralis is elevated from the lateral intermuscular septum, robust vessels are encountered piercing the septum. These perforating vessels are primarily branches of which artery?

A patient is evaluated for foot drop following a traumatic knee dislocation. An MRI reveals an intact common peroneal nerve that is compressed by a fibular head hematoma. In this anatomical region, the nerve wraps around the fibular neck deep to the origin of which muscle?

During an anterolateral approach to the distal third of the humerus, the brachialis muscle is split longitudinally. Which nerve innervates the lateral half of the split brachialis muscle?

A surgeon is performing a standard deltopectoral approach to the shoulder. Which of the following best describes the internervous plane utilized in this approach?

During an anterior (Smith-Petersen) approach to the hip, a superficial internervous plane is developed. Between which two muscles is this plane located?

A patient requires surgical excision of a tumor located within the quadrangular space of the shoulder. Which vascular structure normally accompanies the axillary nerve in this space?

A 45-year-old female presents with isolated weakness in external rotation of the shoulder. EMG reveals isolated denervation of the infraspinatus with normal supraspinatus function. Where is the most likely site of nerve compression?

During a volar Henry approach to the forearm for a radius fracture, the surgeon must mobilize the flexor carpi radialis (FCR) and brachioradialis. What represents the internervous plane for the proximal third of this approach?

A surgeon performs an extensile lateral approach to the calcaneus for an intra-articular fracture. Which nerve is most at risk during the initial skin incision and elevation of the full-thickness flap?

Following an open reduction and internal fixation of a distal radius fracture via a standard volar approach, a patient cannot actively flex the interphalangeal joint of the thumb. Which tendon was most likely injured?

When repairing a distal biceps tendon rupture via a two-incision technique, what structure is at highest risk of iatrogenic injury during the deep posterolateral muscle-splitting exposure?

During an ilioinguinal approach for an anterior column acetabular fracture, life-threatening hemorrhage occurs behind the superior pubic ramus. What vascular anomaly is the most likely source?

Blood supply to the adult femoral head is predominantly derived from the medial femoral circumflex artery (MFCA). Which specific branch of the MFCA provides the vast majority of this perfusion?

A 25-year-old runner complains of chronic exertional anterior compartment syndrome. During surgical release, the surgeon must protect the deep peroneal nerve, which runs closely with which artery?

When performing a standard posterior approach to the hip (Kocher-Langenbeck), which structure is utilized to protect the sciatic nerve during deep retraction?

A patient presents with a severe knee dislocation. Post-reduction examination reveals intact plantar flexion and inversion, but isolated weakness in ankle dorsiflexion and eversion. Which nerve is injured?

During a posterolateral approach to the tibial plateau, the surgeon must identify the common peroneal nerve. Immediately distal to the fibular head, which muscle does the common peroneal nerve dive beneath?

A displaced fracture of the medial epicondyle of the humerus often compromises the ulnar nerve. The ulnar nerve enters the anterior forearm by passing between the two heads of which muscle?

During arthroscopic anterior cruciate ligament (ACL) reconstruction, the surgeon drills the tibial tunnel. To maximally protect the popliteal artery from injury, how should the knee be positioned?

A patient requires a surgical release for De Quervain's tenosynovitis. Which two tendons are located within the targeted first dorsal compartment of the wrist?

A 55-year-old male undergoes open plating for a displaced midshaft humerus fracture. The radial nerve runs in the spiral groove of the humerus between which two muscle heads?

While performing a direct anterior approach to the hip, placement of a blunt retractor directly over the anterior rim of the acetabulum can inadvertently compress which nerve?

During the proximal extension of the anterior (Henry) approach to the radius, the surgeon identifies a leash of vessels that must be ligated to mobilize the mobile wad laterally. These vessels are direct branches of which of the following structures?

A surgeon is performing an ilioinguinal approach for an anterior column acetabular fracture. While working in the second (middle) window, which of the following structures is found immediately medial to the iliopectineal fascia?

When placing lateral mass screws in the subaxial cervical spine (C3-C6) using the Magerl technique, the drill is directed 25 degrees outward (laterally) and 25 degrees upward (cephalad) to primarily avoid injury to which two structures?

A 28-year-old overhead athlete presents with isolated external rotation weakness of the shoulder. An MRI reveals a paralabral cyst located in the spinoglenoid notch. Which of the following physical exam findings is most expected?

During an anatomic reconstruction of the posterolateral corner (PLC) of the knee, identifying the normal anatomic footprint of the popliteus tendon on the femur is critical. Where is it located relative to the lateral collateral ligament (LCL) origin?

When establishing the anterolateral portal during ankle arthroscopy, the incision should be made just lateral to the peroneus tertius tendon. This placement primarily minimizes the risk of injury to which of the following nerves?

A patient sustains a complete sharp laceration of the ulnar nerve at the level of the pisiform. Despite this, they surprisingly maintain normal strength in the deep head of the flexor pollicis brevis and the adductor pollicis. Which of the following anatomical variants best explains this?

During a surgical dislocation of the hip to treat a femoral head fracture, the surgeon performs a trochanteric flip osteotomy. To preserve the primary blood supply to the femoral head, the osteotomy must remain superficial to the external rotator muscles to protect branches of which artery?

A 35-year-old male presents with vague anterior elbow pain and numbness in the radial three and a half digits. Radiographs demonstrate a bony spur projecting from the anteromedial aspect of the distal humerus. Compression at this specific level involves which of the following structures?

When performing a direct lateral (Hardinge) approach to the hip, proximal splitting of the gluteus medius must be strictly limited to less than 3 to 5 cm from the tip of the greater trochanter. This safe zone prevents denervation of the muscle by protecting which nerve?

During resection of a soft tissue sarcoma in the proximal thigh, the surgeon carefully traces the femoral nerve. Which of the following muscles is primarily innervated by a branch of the femoral nerve despite functioning as a medial compartment adductor?

A patient undergoes ORIF of a scaphoid fracture via a volar approach. The surgeon must open the wrist capsule while preserving the critical volar radiocarpal ligaments. Which of the following ligaments is the primary stabilizer preventing volar dislocation of the lunate?

During a microdiscectomy at the L4-L5 level via a traditional posterior interlaminar approach, the surgeon encounters a large paracentral disc herniation. Anatomically, which nerve root is most commonly compressed by this specific herniation, and where does it ultimately exit the spinal canal?

Repair of a posterior horn tear of the medial meniscus using an inside-out technique places certain extra-articular structures at risk. What is the most critical neural structure at risk when placing sutures blindly in the posteromedial corner of the knee?

The Lisfranc ligament is essential for the stability of the midfoot and is often implicated in high-energy tarsometatarsal fracture-dislocations. Which of the following best describes its exact true anatomical attachments?

When performing a surgical dislocation of the hip for a femoroacetabular impingement procedure, preservation of the deep branch of the medial circumflex femoral artery (MCFA) is paramount to prevent avascular necrosis. In relation to the short external rotators, where is this critical vessel consistently located?

A 28-year-old elite pitcher presents with isolated wasting and severe weakness of the infraspinatus muscle. He has full strength in shoulder abduction, and external rotation with the arm abducted to 90 degrees is intact. Entrapment of the involved nerve is most likely occurring at which of the following anatomic locations?

During an anterior cervical discectomy and fusion (ACDF) at the C5-C6 level, the surgeon develops the standard plane between the carotid sheath laterally and the trachea/esophagus medially. Which of the following specific fascial layers must be incised to enter this internervous plane?

A 45-year-old woman complains of proximal volar forearm pain and paresthesias in the radial three and a half digits. Electrodiagnostic testing confirms a high median nerve compression. Which of the following anatomical structures is most likely responsible for this specific entrapment syndrome?

In reconstructing the posterolateral corner (PLC) of the knee, the surgeon must anatomically restore the insertion of the popliteus tendon on the femur. What is its correct anatomic relationship to the fibular collateral ligament (FCL) attachment on the lateral femoral condyle?

During a deltopectoral approach to the shoulder, the cephalic vein is identified. It is typically retracted laterally with the deltoid to preserve its major tributaries. If the dissection proceeds too aggressively medial to the conjoined tendon, which of the following nerves is at greatest risk of direct injury?

A trauma surgeon is performing an ilioinguinal approach for an anterior column acetabular fracture. While working in the second (middle) window, massive acute hemorrhage occurs. Which of the following vascular structures is the most likely source of this bleeding?

Surgical treatment of a recalcitrant trigger finger involves incising the A1 pulley. During flexor tendon exploration, which of the following combinations of pulleys are the most critical biomechanical stabilizers that must be preserved to prevent significant tendon bowstringing?

The anterolateral approach to the distal humerus is often utilized for fracture fixation, requiring exposure and protection of the radial nerve. At what approximate distance proximal to the radiocapitellar joint does the radial nerve pierce the lateral intermuscular septum to enter the anterior compartment?

During an anterior (Smith-Petersen) approach to the hip, a true internervous plane is utilized. Proximally, this surgical interval is developed between muscles innervated by which two nerves?

Tarsal tunnel syndrome involves entrapment of the tibial nerve. In relation to the other structures located posterior to the medial malleolus, where does the main neurovascular bundle lie within the tarsal tunnel?

During the distal extent of the volar (Henry) approach to the radius, the pronator quadratus must be elevated to visualize the volar cortex. To maintain its blood supply and allow for an adequate repair at closure, from which border should the muscle be detached?

The transpsoas lateral approach to the lumbar spine places the lumbar plexus at significant risk of iatrogenic injury. At the L4-L5 disc space level, where is the lumbar plexus most consistently located within the psoas major muscle?

A 30-year-old bodybuilder presents with poorly localized posterior shoulder pain and weakness in external rotation. MRI reveals an isolated paralabral cyst compressing the contents of the quadrilateral space. Which of the following muscles acts as the superior border of this anatomic space?

Surgical release for De Quervain's tenosynovitis requires incising the extensor retinaculum over the first dorsal extensor compartment. Which of the following sensory nerves is at greatest risk of iatrogenic injury or neuroma formation during this superficial dissection?