Question 1

Which of the following statements regarding ganglions is false:

Explanation

Transillumination is a hallmark of ganglions. Because of the location from which ganglia arise and the dissection performed during resection, a decrease in range of motion can be seen postoperatively. Needle aspiration is diagnostic and can be therapeutic, however, recurrence rates as high as 95% have been reported. Volar ganglia can often be intimately associated with the radial artery. Ganglia may often be multilobulated.

Question 2

Dorsal wrist ganglions originate from the:

Explanation

Dorsal wrist ganglia do not arise from the dorsal capsule, EDC tendon, capitolunate joint, or dorsal intercarpal ligament. Dorsal wrist ganglia arise from the scapholunate ligament. Some surgeons advocate excising a small rim of the scapholunate ligament to avoid recurrence.C orrect Answer: Scapholunate ligament

Question 3

Ganglions of the distal interphalangeal (DIP) joints of the fingers are called:

Explanation

Ganglions arising at the DIP joints are called mucous cysts and ganglions from the flexor tendon in the palm are called retinacular cysts. Bouchard nodes are osteophytes that develop at the proximal interphalangeal joint. Heberden nodes are bony spurs at the dorsal aspect of the DIP joint and are present in osteoarthritis. Inclusion cysts are mobile, nonadherent to skin, and can occur anywhere on a hand.

Question 4

Management of a mucous cyst entails:

Explanation

Treatment of mucous cysts, which are ganglions of the distal interphalangeal joint associated with osteoarthritic changes, entails excision of the cyst and osteophyte resection of fusion. Aspiration only or aspiration of the cyst with injection of hyaluronidase is not indicated or efficacious in the treatment of mucous cysts because the osteophyte must be addressed. Injection of steroids also fails to address the underlying cause of these cysts. Arthrodesis of the distal interphalangeal joint is not necessary in the treatment of typical mucous cysts.C orrect Answer: Excision and resection of osteophytes

Question 5

A 30-year-old black woman presents with complaints of pain in the tip of her right index finger. The pain started approximately 6 months ago and becomes intense in cold weather. She also states that her nail on the index finger does not look as good as the others despite regular manicures. You notice a bluish discoloration and ridging of the nail. The nail is not split, but it appears clubbed. The patient does not have a history of respiratory or hemodynamic disease and appears healthy. The nail is exquisitely tender on pressure, but no mass is palpable. Two-point discrimination is intact and capillary refill is good. Radiographs do not reveal bony destruction, but you notice pressure indentation over the distal phalanx. The joint space is preserved, and the patient has full range of motion. The most likely diagnosis is:

Explanation

This patient presents with the classic triad of glomus tumor: sharp lancinating pain, point tenderness, and cold sensitivity. Localized bluish discoloration is also strongly suggestive of a glomus tumor. Giant cell tumors can be found on the fingertip, however, a presentation of a giant cell tumor with these symptoms would be unusual. Mucous cysts would be part of the differential but does not cause a bluish discoloration or cold insensitivity. An acute paronychia would be painful and erythematous is infectious. A mucous cyst is not infectious. This classic triad does not describe a turret exotosis.

Question 6

A 30-year-old black woman presents with complaints of pain in the tip of her right index finger. The pain started approximately 6 months ago and becomes intense in cold weather. She also states that her nail on the index finger does not look as good as the others despite regular manicures. You notice a bluish discoloration and ridging of the nail. The nail is not split, but it appears clubbed. The patient does not have a history of respiratory or hemodynamic disease and appears healthy. The nail is exquisitely tender on pressure, but no mass is palpable. Two-point discrimination is intact and capillary refill is good. Radiographs do not reveal bony destruction, but you notice pressure indentation over the distal phalanx. The joint space is preserved, and the patient has full range of motion. The next step in management includes:

Explanation

This is a classic case of a glomus tumor with cold intolerance and nail deformity. Imaging studies often are inconclusive, although computed tomography scans may show cortical reaction. This patient is symptomatic and should receive definitive treatment. It should be noted that magnetic resonance imaging is increasingly helpful for nonclassical presentations of finger pain.

Question 7

A 30-year-old black woman presents with complaints of pain in the tip of her right index finger. The pain started approximately 6 months ago and becomes intense in cold weather. She also states that her nail on the index finger does not look as good as the others despite regular manicures. You notice a bluish discoloration and ridging of the nail. The nail is not split, but it appears clubbed. The patient does not have a history of respiratory or hemodynamic disease and appears healthy. The nail is exquisitely tender on pressure, but no mass is palpable. Two-point discrimination is intact and capillary refill is good. Radiographs do not reveal bony destruction, but you notice pressure indentation over the distal phalanx. The joint space is preserved, and the patient has full range of motion. Based on your clinical diagnoses, the histological findings will include which of the following:

Explanation

Glomus tumors consist of well-formed vascular channels with nonmyelinated nerve endings. Glomus tumors are not associated with mucous islands or giant cells. Negatively birefringent crystals are found in patients with gout. The presentation of this patient does not suggest gout. Amorphous calcium in a pseudocapsule is diagnostic of calcinosis. C alcinosis occurs intracutaneoulsy or subcutaneously. These deposits can be tender but are not effected by changes in weather, as are glomus tumors.

Question 8

Glomus tumors are characterized by all of the following except:

Explanation

Glomera are neuromyoarterial apparatuses that regulate temperature.

Question 9

All of the following are characteristic of hemangiomas except:

Explanation

Cavernous hemangiomas are noninvoluting hemangiomas and require surgical excision.

Question 10

Pseudoaneurysms differ from true aneurysms in that:

Explanation

Pseudoaneurysms occur secondary to penetrating trauma and have a fibrous wall, compared to true aneurysms that have all the elements of an arterial wall.

Question 11

Neurofibromas are characterized by all of the following except:

Explanation

Neurofibromas are benign tumors of neural origin that are transmitted as an autosomal dominant trait with variable penetrance. Neurofibromas are associated with cutaneous manifestations like cafe-au-lait spots and axillary freckles. They may be dumbbell shaped and can be identified with magnetic resonance imaging, which is especially helpful for deeper multiple lesions. They are infiltrative, making excision with preservation of peripheral nerve function difficult thus requiring bridge grafting for significant motor or sensory funtional requirements.

Question 12

Recklinghausens disease is associated with all of the following except:

Explanation

Diffuse neurofibromatosis is a separate clinical presentation and is not associated with Recklinghausenâ s disease.

Question 13

Schwannomas are differentiated from neurofibromas by all of the following except:

Explanation

Schwann cells contribute to schwannoma and neurofibroma.

Question 14

All of the following are true for infantile digital fibroma except:

Explanation

Eighty percent of infantile digital fibromata appear before a child's first birthday. They are exclusive to the fingers and toes and are usually painless. Infantile digital fibromata are often small and the same color as the skin. On histological examination, intracytoplasmic inclusion bodies are present. Although benign, the fibromata are locally aggressive. They do not metastaaize, but recurrences after wide local excision are common. Surgery is indicated when deformity or contracture is imminent.

Question 15

Felon complications include all of the following except:

Explanation

Felons that are chronic or neglected may penetrate adjacent structures such as the distal phalanx, nailbed, or distal interphalangeal joint. They can also contribute to the formation of a pyogenic flexor tenosynovitis. C ollar button abscesses are localized to web space. They typically arise from direct inoculation, not from distant felons.

Question 16

Which of the following is not a classic Kanavel sign of flexor tenosynovitis:

Explanation

The cardinal signs of flexor tenosynovitis described by Kanavel include pain on passive extension, flexion attitude of the finger, tenderness of flexor sheath, and swollen finger.

Question 17

Septic flexor tenosynovitis may involve all of the following areas except the:

Explanation

The radial and ulnar bursae are extensions of the tendon sheaths of the flexor pollicis longus and the flexor digitorum profundus of the small fingers. They can easily be involved in a case of pyogenic flexor tenosynovitis. Although not direct extensions of the flexor sheaths, the thenar space and Parona's space are adjacent to the flexor sheaths and can be involved in suppurative conditions. The snuffbox, however, does not have any contributions from the flexor system and is not usually involved in cases of pyogenic flexor tenosynovitis.

Question 18

Regarding the management of web space abscess, which of the following statements is not true:

Explanation

Transverse incisions can lead to contractures that limit finger abduction. Leaving wounds open allow for continued drainage. If preferred, closed suction drains can be used after closure of the wound. All devitalized tissue must be debrided and all signs of infection removed and irrigated copiously. Early motion is encouraged to prevent stiffness.

Question 19

Meleneyâ s infection is a:

Explanation

Found in necrotizing fasciitis, Meleneyâ s infection is a spreading ulcer rimmed with gangrenous skin. The affected area must be debrided immediately. Cultures are taken at the time of surgery to tailor antibiotic coverage. Amputation is not unusual to control the spread of the gangrenous infection.

Question 20

Meleneyâ s infection is caused by:

Explanation

Aerobic hemolytic staphylococci and microaerophyllic non-hemolytic streptococci synergistically act to produce Meleneys infection. Meleney's infection is a gangrenous infection that often results after a small injury. The infection is characterized by significant, rapid swelling with gangrenous changes.

Question 21

The most common pathogen for osteomyelitis of phalanges is:

Explanation

Staphylococcus aureus is the most common pathogen that causes osteomyelitis in the hand. Most cases of osteomyelitis in the hand are due to direct extension. Other pathogens can be found if there is a contaminated injury that penetrates directly into the bone. H. infuenza , mixed pathogens, and Pasturella multocida are less likely causes of osteomyelitis and are often caused by direct inoculation injuries or bites.

Question 22

The most common pathogen causing septic arthritis in the hand is:

Explanation

Staphylococcus aureus is the most common pathogen that causes septic arthritis in the hand. The second most common pathogen is streptococcus species infections, which are often the result of trauma. Treatment includes incision and drainage with copius irrigation.

Question 23

"C ollar button" abscess refers to:

Explanation

Collar button abscess is an infection of web space and is usually a result of penetrating trauma. Treatment of such abscesses requires incision and drainage through dorsal and palmar incisions. Care must be taken to avoid the neurovascular bundles. Finger pulp infections are known as felon. Infections involving Parona's space is typically involved in a horseshoe abscess. Eponychial infections are limited to the nail fold. C ollar button abscesses do not include joint involvement.C orrect Answer: Web space infection

Question 24

A 35-year-old woman is bitten on her left index finger by a snake in her backyard. Management of snake bites includes all of the following except:

Explanation

There are different snake bite protocols depending on the species of snake. However, common steps in all snake bite protocols include keeping the patient emotionally and physically still, calling for help immediately, applying a moderately tight tourniquet proximally to prevent further spread of venom, and capture or identification of the snake. Local injection of the antivenin in the fingers or toes is contraindicated.C orrect Answer: Injecting antivenin locally based on recommended guidelines

Question 25

C ardinal signs of evenomation include all of the following except:

Explanation

The cardinal signs of evenomation appear between 10 minutes and 4 hours after a person is bitten. The signs include fang marks, pain, swelling, and local necrosis. Cyanosis is not considered a cardinal sign of evenomation.

Question 26

All of the following nerves are involved in infection with Mycobacterium leprae except the:

Explanation

Mycobacterium leprae causes skin, nerve, and tendon sheath infections. M leprae commonly affects the hands because it has a predilection for cool parts of the body. M leprae causes neuropathy, which frequently involves the ulnar nerve at the elbow and the median nerve at the wrist. The resulting limb deformities require various surgical procedures. C ranial nerves and autonomic nerves are not affected.

Question 27

A 24-year-old white man presents to the emergency department. He was bitten on his fist while fighting with another man. You notice teeth marks on the dorsum of the metacarpophalangeal (MC P) joint of the right middle finger. The bite does not appear to be deep because the joint is not exposed, and you can see the extensor tendon, which seems intact. The patient has active extension at the MC P joint. The wound is red and swollen, but there is no tenderness or redness on the volar aspect of the MCP joint. The patient has some limitation in range of motion. He is afebrile. Radiographs reveal air in the joint but no joint dislocation or fracture, and there is no neurovascular deficit. All of the following are appropriate steps in the management of this patient except:

Explanation

Human bite wounds on the hand are typically found over the MP joint. The mechanism of injury is a clenched-fist blow to the mouth. Oral flora enters the wound, which often communicates with the joint. Eikenella corrodens is frequently cultured from human bite wounds, but the most common pathogen is staphylococcus aureus. Appropriate treatment includes the administration of tetanus toxoid, exploration if there is air in the joint or frank infection, observation, intravenous antibiotics, arm elevation, and splinting. All bites over joints should be assumed to penetrate and require formal incision and drainage.

Question 28

A 24-year-old man presents to the emergency department. He was bitten on his fist while fighting with another man. You notice teeth marks on the dorsum of the metacarpophalangeal (MC P) joint of the right middle finger. The bite does not appear to be deep because the joint is not exposed, and you can see the extensor tendon, which seems intact. The patient has active extension at the MC P joint. The wound is red and swollen, but there is no tenderness or redness on the volar aspect of the MCP joint. The patient has some limitation in range of motion. He is afebrile. Radiographs reveal soft tissue involvement but no joint dislocation or fracture, and there is no neurovascular deficit. An important step in assessment of human bites is:

Explanation

Evaluation for tendon injury in a clenched-fist position is essential because tendons slide proximally in the open-hand position. Involvement of tendon or joint usually necessitates surgical debridement.C orrect Answer: Evaluation for tendon injury in clenched-fist position

Question 29

A 24-year-old white man presents to the emergency department. He was bitten on his fist while fighting with another man. You notice teeth marks on the dorsum of the metacarpophalangeal (MC P) joint of the right middle finger. The bite does not appear to be deep because the joint is not exposed, and you can see the extensor tendon, which seems intact. The patient has active extension at the MC P joint. The wound is red and swollen, but there is no tenderness or redness on the volar aspect of the MCP joint. The patient has some limitation in range of motion. He is afebrile. Radiographs reveal soft tissue involvement but no joint dislocation or fracture, and there is no neurovascular deficit. After cultures are taken, the next important step in treatment is:

Explanation

A patient with a human bite must be admitted for IV antibiotics and observation. If left untreated, human bites are commonly infected by a mixed flora of organisms. Therefore, they must be treated diligently.C orrect Answer: Admit and administer IV antibiotics

Question 30

A 24-year-old white man presents to the emergency department. He was bitten on his fist while fighting with another man. You notice teeth marks on the dorsum of the metacarpophalangeal (MC P) joint of the right middle finger. The bite does not appear to be deep because the joint is not exposed, and you can see the extensor tendon, which seems intact. The patient has active extension at the MC P joint. The wound is red and swollen, but there is no tenderness or redness on the volar aspect of the MCP joint. The patient has some limitation in range of motion. He is afebrile. Radiographs reveal soft tissue involvement but no joint dislocation or fracture, and there is no neurovascular deficit. The most appropriate antibiotic treatment includes:

Explanation

Imipenam and ciprofloxacin provide treatment for gram-negative and gram- positive organisms.C orrect Answer: Imipenam and ciprofloxacin

Question 31

Which of the following organisms is most likely found in a cat bite:

Explanation

Pasteurella multocida is the most common organism found in animal bites.

Question 32

Which of the following is the atypical mycobacterium that infects a penetrating wound sustained in an aquatic environment:

Explanation

Tuberculosis is the most common chronic infection found in the hand. Mycobacterium marinum is the atypical mycobacterium that can infect a wound sustained in a marine environment, freshwater lake, or tropical fish tanks. It is also called swimming pool granuloma or fish tank granuloma.

Question 33

Which of the following is not true for infections caused by Mycobacterium marinum:

Explanation

Tuberculous infections are chronic infections and do not produce acute signs of inflammation. Therefore, pain and tenderness are present in these infections but warmth and redness are absent. Abscesses produced in tuberculous infections are termed "cold abcesses."

Question 34

Which of the following fascial structures does not contribute to the formation of the spiral cord:

Explanation

The pretendinous band, spiral band, lateral digital sheet, and Grayson's ligament are all parts of the normal fascia that contribute to the formation of the spiral cord. C leland's ligament is not involved at all in the disease process.

Question 35

Which of the following structures contribute to the formation of the spiral cord:

Explanation

The spiral cord is formed from the pretendinous band, spiral band, Grayson's ligament, and lateral digital sheet. Cleland's ligament is not affected in Dupuytren's contracture. Remember that bands and ligaments give rise to cords, which are the diseased state.

Question 36

Surgical release in Dupuytrenâ s disease is indicated in which of the following:

Explanation

The indication for surgery in Dupuytrenâ s disease is MP joint contracture larger than 30° and any degree of PIP joint deformity. The other answers are incorrect because they are subjective descriptions and do not necessarily indicate joint involvement.

Question 37

Skin pits in Dupuytrenâ s disease are caused by:

Explanation

The longitudinal fibers forming layer 1 of the palmar aponeurosis insert into the dermis and, when contracted, give rise to skin pits. The pretendinous bands give rise to the central cord. C ontractures of the natatory ligament give rise to the natatory cord. Vertical fibers and septae do not give rise to pits.C orrect Answer: Longitudinal fibers of palmar aponeurosis inserting into the skin

Question 38

An otherwise healthy man has Dupuytrenâ s disease, which involves his small finger with 40° proximal interphalangeal joint involvement. The preferred surgery in this patient is:

Explanation

A partial fasciectomy is the preferred surgery in this situation. It is recommended that involved fascial cords be resected rather than performing prophylactic fasciectomies. C are must be taken to preserve the neurovascular bundles. Arthrodesis, arthroplasty, and osteotomies are salvage procedures meant for recurrent disease. Fasciotomy has been recommended for elderly patients who cannot tolerate a long operation.

Question 39

Marjolins ulcers are risk factors for which of the following tumors:

Explanation

Marjolins ulcers are malignant degenerations in chronic skin ulcers, sinuses, and burn scars and are risk factors for squamous cell carcinoma. Any patient with chronic, nonhealing ulcers should undergo biopsy for malignant degeneration. Basal cell carcinoma, malignant melanoma, synovial sarcoma, and osteosarcoma are not commonly associated with Marjolin's ulcer.

Question 40

Which of the following tumors rarely metastasizes:

Explanation

Dermatofibrosarcoma protuberans presents as a variably colored, slow- growing nodule involving the subcutaneous tissue. This tumor has a low incidence of metastasis; however, the recurrence rate is high even with wide local excision.

Question 41

Lymph node involvement is common in all of the following tumors except:

Explanation

Basal cell carcinomas rarely metastasize. Malignant sweat gland tumors, malignant melanoma, and Merkel's cell carcinoma are aggressive. Treatment usually includes regional lymphadenectomy. Squamous cell carcinoma is one of the most common hand malignancies and has the capacity to metastasize via the lymphatics.

Question 42

Which of the following is not a characteristic of an acrolentiginous melanoma:

Explanation

Acrolentiginous melanomas are usually flat, pigmented lesions. These melanomas often occur in older patients, affecting the palm and nail bed. At the time of presentation, acrolentiginous melanomas are frequently metastasized.

Question 43

Nevi at greatest risk for malignant degeneration are:

Explanation

Giant congenital hairy nevi, dysplastic nevi, senile lentigo, and congenital melanocytic nevi have significant risk for malignant degeneration. Nevus sebaceous is present at birth in the head and neck region and has a 10% incidence of malignant transformation. Blue nevi, junctional nevi, and compound nevi have lower risks for transformation.

Question 44

All of the following are risk factors for malignant melanoma except:

Explanation

Sun exposure is the most important risk factor for melanoma. Family history, atypical nevi, and an immunosuppressive state increases an individual's risk for developing melanoma. It is unknown if tanning lotions cause malignant melanomas.

Question 45

Which of the following statements is true regarding soft tissue sarcomas:

Explanation

Soft tissue sarcomas in the hand present as painless lesions, do not metastasize to bone, and although local control is better with radical resection, there is no improvement in overall survival when compared to wide excision. Soft tissue sarcomas should not be "shelled out."C orrect Answer: Patients with soft tissue sarcomas of the hand have worse prognosis than patients with similar tumors in other extremities.

Question 46

Which of the following tumor metastasizes to lungs:

Explanation

Squamous cell carcinoma and basal cell carcinoma do not commonly metastasize to the lungs. Actinic keratoses are premalignant lesions that progress into squamous cell carcinomas. Schwannomas are common benign nerve tumors.

Question 47

Which of the following is not a characteristic of synovial sarcomas:

Explanation

Synovial sarcomas are high grade malignant soft tissue sarcomas, in which metastases can occur years after surgery. Long term followup is necessary. They arise close to joints, tendons or bursa and lymphatic spred is common. Histology reveals spindle and epithelial type cells with menophasic or biphasic pattern. Treatment includes wide resection and radiation, chemotherapy is not usually used.

Question 48

C haracteristic histological features of malignant schwannoma are best described as:

Explanation

The histological features of malignant schwannoma have characteristic fusiform cells with neoplastic schwann cells and nerve fascicles.

Question 49

Which of the following terms is not used in reference to macrodactyly:

Explanation

Symbrachydactyly is a term that encompasses all variations of shortened digits. Symbrachydactyly may be associated with syndactylies, but it is not a term used in reference to macrodactyly.

Question 50

Most cases of macrodactyly are:

Explanation

The majority of patients (90%) present with unilateral macrodactyly, and men are more often affected than women. Macrodactyly is most frequently found in the index finger, followed by the long finger, thumb, ring, and little fingers. Typically, two digits are affected â most commonly the thumb and index or the index and long.C orrect Answer: Unilateral and affect men more often than women

Question 51

A 19-year-old female collegiate soccer player sustains an anterior cruciate ligament (ACL) tear. Which of the following anatomic factors is most strongly associated with an increased risk of non-contact ACL injuries in female athletes?

Explanation

A narrow intercondylar notch width is a well-established anatomical risk factor for non-contact ACL tears, particularly in females. Increased posterior tibial slope and increased generalized laxity are also recognized risk factors.

Question 52

According to the Musculoskeletal Infection Society (MSIS) criteria, which of the following is considered a major criterion for the diagnosis of periprosthetic joint infection (PJI) following a total hip arthroplasty?

Explanation

The major criteria for diagnosing PJI are a sinus tract communicating with the prosthesis or two positive periprosthetic cultures with phenotypically identical organisms. The other listed options represent minor criteria.

Question 53

A 12-year-old obese male presents with a stable slipped capital femoral epiphysis (SCFE) and undergoes in situ pinning. Six months later, he develops severe hip stiffness and a flexion contracture. Radiographs show significant uniform loss of the joint space. What is the most likely diagnosis?

Explanation

Chondrolysis is a severe complication of SCFE characterized by progressive stiffness, pain, and uniform loss of joint space. It is strongly associated with unrecognized pin penetration into the joint space during fixation.

Question 54

A 45-year-old male sustains a severe, closed highly comminuted tibial pilon fracture (OTA/AO 43-C3) with massive soft tissue swelling and fracture blisters. What is the most appropriate initial management?

Explanation

In high-energy pilon fractures with severe soft tissue compromise, immediate ORIF carries an unacceptably high risk of wound breakdown and infection. A staged approach using spanning external fixation followed by delayed ORIF is the standard of care.

Question 55

A 35-year-old male presents with chronic wrist pain. Radiographs reveal a scaphoid nonunion advanced collapse (SNAC) pattern with arthritis involving the radioscaphoid and capitolunate joints. The radiolunate joint is spared. What is the most appropriate surgical intervention?

Explanation

In a Stage II or III SNAC wrist where the capitolunate joint is arthritic but the radiolunate joint is spared, a scaphoid excision and four-corner fusion is indicated. Proximal row carpectomy is contraindicated if the capitate head is arthritic.

Question 56

A 25-year-old male is involved in a motor vehicle accident and sustains a burst fracture of the C1 ring (Jefferson fracture). Which radiographic finding best indicates incompetence of the transverse atlantal ligament?

Explanation

Spence's rule states that a combined lateral mass displacement of the atlas greater than 6.9 mm on an AP open-mouth radiograph indicates a rupture of the transverse atlantal ligament. This implies an unstable C1 fracture requiring rigid immobilization or surgical stabilization.

Question 57

A 30-year-old female presents with knee pain. Radiographs show an eccentric, lytic lesion in the distal femoral epiphysis extending to the subchondral bone without a sclerotic margin. Biopsy reveals multinucleated giant cells. Which medication acts by binding to RANKL to treat this condition?

Explanation

The clinical and histologic findings describe a giant cell tumor (GCT) of bone. Denosumab is a monoclonal antibody that binds to RANKL, inhibiting osteoclast-like giant cells, and is used for advanced or recurrent GCTs.

Question 58

A patient sustains an anteroposterior compression type III (APC-III) pelvic ring injury. Which of the following ligamentous structures is completely disrupted in this injury pattern, distinguishing it from an APC-II injury?

Explanation

An APC-III injury involves complete disruption of both the anterior and posterior sacroiliac ligaments, leading to complete pelvic instability. An APC-II injury disrupts the anterior SI, sacrospinous, and sacrotuberous ligaments but spares the strong posterior SI ligaments.

Question 59

A 4-month-old infant is being treated with a Pavlik harness for developmental dysplasia of the hip (DDH). During a follow-up visit, the infant is noted to have absent spontaneous extension of the knee on the treated side. Which nerve is most likely compressed due to improper harness positioning?

Explanation

Hyperflexion of the hip in a Pavlik harness can compress the femoral nerve, leading to decreased quadriceps function and absent knee extension. Treatment involves loosening or temporarily removing the anterior straps.

Question 60

During viscoelastic testing of a tendon, a constant load is applied over time, resulting in progressive deformation (elongation) of the tissue. What is this biomechanical phenomenon called?

Explanation

Creep is the time-dependent elongation of a viscoelastic material under a constant load. Stress relaxation is the decrease in internal stress over time when the material is held at a constant length.

Question 61

A 40-year-old male suffers a seizure and subsequently complains of severe right shoulder pain. Radiographs show a "lightbulb" sign on the AP view and an empty glenoid sign. What is the most common associated bony defect seen with this specific injury?

Explanation

The patient has a posterior shoulder dislocation, classically caused by seizures or electrical shock. The most common associated defect is a reverse Hill-Sachs lesion, which is an impaction fracture of the anteromedial humeral head.

Question 62

A 65-year-old female presents 8 months after a posterior-stabilized total knee arthroplasty (TKA) complaining of a painful "catch" and audible pop when extending her knee from a flexed position. What is the underlying pathophysiology of this complication?

Explanation

This is a classic presentation for patellar clunk syndrome, which occurs predominantly in posterior-stabilized TKAs. It is caused by a fibrous nodule on the deep surface of the distal quadriceps tendon catching in the intercondylar box during extension.

Question 63

A 75-year-old female undergoes closed reduction and percutaneous pinning for a displaced femoral neck fracture. Six months later, radiographs confirm a nonunion. Which vascular supply was most likely disrupted at the time of the initial injury, contributing to this outcome?

Explanation

The medial femoral circumflex artery (MFCA) provides the predominant blood supply to the adult femoral head via the lateral epiphyseal artery. Disruption of this vessel in displaced femoral neck fractures significantly increases the risk of avascular necrosis and nonunion.

Question 64

A 28-year-old carpenter sustains a laceration to the volar aspect of his index finger at the level of the proximal phalanx, resulting in loss of both superficialis and profundus tendon function. This injury corresponds to which flexor tendon zone?

Explanation

Zone II, historically known as "no man's land," extends from the A1 pulley to the insertion of the flexor digitorum superficialis (FDS). Injuries here involve both the FDS and FDP tendons within the narrow fibro-osseous sheath.

Question 65

A 16-year-old male is diagnosed with high-grade intramedullary osteosarcoma of the distal femur. He undergoes neoadjuvant chemotherapy followed by limb-salvage surgery. What is the most important histologic prognostic factor for long-term survival in this patient?

Explanation

The percentage of tumor necrosis in the surgical specimen following neoadjuvant chemotherapy is the single most important prognostic factor in osteosarcoma. Greater than 90% necrosis indicates an excellent response and better overall survival.

Question 66

A surgeon is considering using a stainless steel screw in combination with a titanium plate for fracture fixation. Which of the following best describes the primary risk associated with mixing these two metals?

Explanation

Mixing two dissimilar metals with different electrochemical potentials in an electrolytic environment (like the body) leads to galvanic corrosion. The less noble metal will corrode at an accelerated rate, potentially leading to implant failure.

Question 67

A 14-year-old female gymnast presents with chronic mechanical lower back pain. Lateral lumbar radiographs demonstrate a 60% anterior translation of L5 on S1. According to the Meyerding classification, what grade is this spondylolisthesis?

Explanation

The Meyerding classification grades the percentage of forward slip: Grade I (0-25%), Grade II (26-50%), Grade III (51-75%), Grade IV (76-100%), and Grade V (>100%). A 60% slip is categorized as Grade III.

Question 68

A 6-year-old boy sustains a significantly displaced extension-type supracondylar humerus fracture. On examination, he has weakness of thumb interphalangeal joint flexion and index finger distal interphalangeal joint flexion. Which nerve is injured?

Explanation

The anterior interosseous nerve (AIN), a branch of the median nerve, is the most commonly injured nerve in extension-type supracondylar humerus fractures. Injury manifests as an inability to make an "OK" sign due to weakness of the FPL and index FDP.

Question 69

A 24-year-old football player sustains a hyperplantarflexion injury to his midfoot. Radiographs show widening between the base of the first and second metatarsals. The injured Lisfranc ligament normally connects which two structures?

Explanation

The Lisfranc ligament is a strong interosseous ligament connecting the lateral aspect of the medial cuneiform to the medial base of the second metatarsal. It provides critical stability to the tarsometatarsal joint complex.

Question 70

In Scapholunate Advanced Collapse (SLAC) of the wrist, which articular surface is typically spared due to its concentric articulation?

Explanation

The radiolunate joint is typically spared in SLAC wrists because the lunate maintains a concentric, congruent articulation with the lunate fossa of the distal radius. This distinct biomechanical feature allows for motion-preserving salvage procedures like the four-corner fusion.

Question 71

In the Young-Burgess classification, an Anteroposterior Compression Type III (APC III) pelvic ring injury is characterized by the complete disruption of which of the following posterior structures?

Explanation

APC III injuries involve complete disruption of the pubic symphysis anteriorly and all posterior stabilizing structures. This includes both the anterior and posterior sacroiliac ligaments, as well as the sacrotuberous and sacrospinous ligaments, leading to complete spinopelvic instability.

Question 72

Prophylactic in situ pinning of the contralateral asymptomatic hip in Slipped Capital Femoral Epiphysis (SCFE) is most strongly indicated in a patient with which of the following underlying conditions?

Explanation

Endocrine disorders, such as hypothyroidism and renal osteodystrophy, significantly increase the risk of bilateral SCFE. In these populations, prophylactic pinning of the contralateral asymptomatic hip is highly recommended due to the high rate of subsequent slippage.

Question 73

A "Segond fracture" seen on an anteroposterior radiograph of the knee is considered pathognomonic for an anterior cruciate ligament (ACL) tear. This fracture represents an avulsion of which of the following structures?

Explanation

The Segond fracture is a cortical avulsion off the proximal lateral tibia. It specifically represents an avulsion of the anterolateral capsule, predominantly involving the anterolateral ligament (ALL).

Question 74

Which of the following is the true neoplastic cell population in a Giant Cell Tumor (GCT) of bone?

Explanation

The neoplastic cells in GCT are the spindle-shaped mononuclear cells of osteoblastic lineage. The hallmark multinucleated giant cells are actually reactive osteoclast-like cells recruited by RANKL expression from the mononuclear cells.

Question 75

According to the Rule of Spence, an open-mouth odontoid radiograph showing total lateral overhang of the C1 lateral masses on C2 of greater than 6.9 mm indicates a rupture of which structure?

Explanation

A combined lateral overhang of the C1 lateral masses on C2 exceeding 6.9 mm (or 8.1 mm accounting for radiographic magnification) suggests a rupture of the Transverse Atlantal Ligament (TAL). This represents an unstable Jefferson fracture variant requiring rigid stabilization.

Question 76

Which of the following fixation methods promotes fracture healing primarily through intramembranous ossification (primary bone healing)?

Explanation

Primary bone healing occurs without a cartilaginous intermediate (callus) under conditions of absolute stability and intimate cortical contact. Compression plating achieves this, allowing direct osteoclastic tunneling and osteoblastic bone formation.

Question 77

Squeaking in a total hip arthroplasty utilizing ceramic-on-ceramic bearing surfaces is most commonly associated with which of the following biomechanical phenomena?

Explanation

Squeaking in ceramic-on-ceramic total hip arthroplasty is highly correlated with edge loading and micro-separation. This is typically caused by acetabular cup malposition, specifically excessive abduction or anteversion.

Question 78

During a total knee arthroplasty, the surgeon notes that the trial components are tight in extension but symmetric and well-balanced in flexion. What is the most appropriate next step?

Explanation

A knee that is tight in extension but balanced in flexion requires selective enlargement of the extension gap. This is achieved by releasing the posterior capsule or resecting additional distal femur, without altering the flexion gap.

Question 79

A 3-month-old infant is being treated for developmental dysplasia of the hip (DDH) with a Pavlik harness. Hyperflexion of the hips in the harness places the child at highest risk for which of the following complications?

Explanation

Hyperflexion of the hips in a Pavlik harness can compress the femoral nerve against the inguinal ligament, leading to transient femoral nerve palsy. In contrast, excessive abduction is the primary risk factor for avascular necrosis.

Question 80

In the evaluation of anterior shoulder instability, an Anterior Labroligamentous Periosteal Sleeve Avulsion (ALPSA) lesion differs from a classic Bankart lesion in which of the following ways?

Explanation

In an ALPSA lesion, the anterior labrum is avulsed from the glenoid rim, but the anterior scapular periosteum remains intact. This intact periosteal sleeve allows the labroligamentous complex to displace medially and inferiorly.

Question 81

A 65-year-old woman on long-term bisphosphonate therapy presents with prodromal thigh pain. Radiographs show cortical thickening and a transverse radiolucent line on the lateral aspect of the femoral diaphysis. What is the recommended management?

Explanation

The presence of prodromal thigh pain combined with a radiographic "beaking" or a radiolucent line on the lateral femoral cortex indicates an impending atypical femoral fracture. The standard of care is prophylactic intramedullary nailing to prevent complete displacement.

Question 82

In the flexor tendon zone classification of the hand, Zone II extends from the insertion of the flexor digitorum superficialis (FDS) proximally to which of the following landmarks?

Explanation

Zone II, historically known as "no man's land" due to poor primary repair outcomes, begins at the proximal edge of the A1 pulley near the distal palmar crease. It ends distally at the insertion of the FDS tendon on the middle phalanx.

Question 83

A 45-year-old female presents with severe paroxysmal pain in her right ring finger, which is severely exacerbated by cold temperatures. Point tenderness is noted over the nail bed, and the nail plate shows a faint bluish discoloration. What is the most characteristic histological finding of this lesion?

Explanation

The clinical presentation is classic for a glomus tumor, a painful, cold-sensitive hamartoma of the glomus body. Histologically, they feature solid sheets of uniform, round-to-oval cells (glomus cells) surrounding capillary vessels.

Question 84

A cyclist presents with numbness in the ring and small fingers along with weakness in finger abduction. Sensation over the dorsal ulnar aspect of the hand is preserved. Where is the most likely site of ulnar nerve compression?

Explanation

Compression in Zone 1 of Guyon's canal affects both the motor and sensory branches of the ulnar nerve. Preserved dorsal ulnar sensation rules out cubital tunnel syndrome, as the dorsal ulnar cutaneous nerve branches off proximal to the wrist.

Question 85

A 25-year-old rugby player presents with an inability to actively flex the distal interphalangeal (DIP) joint of his ring finger after grabbing an opponent's jersey. Radiographs show a bony avulsion fragment retracted to the level of the proximal interphalangeal (PIP) joint. According to the Leddy and Packer classification, what type of injury is this?

Explanation

In a Leddy and Packer Type II Jersey finger, the flexor digitorum profundus (FDP) tendon retracts to the level of the PIP joint. It is held in this position by the intact vinculum longum, which preserves some of its blood supply.

Question 86

A 6-year-old boy sustains a completely displaced, extension-type supracondylar humerus fracture. The distal fragment is displaced posteromedially. Which nerve is most commonly at risk in this specific displacement pattern?

Explanation

In posteromedial displacement of an extension-type supracondylar fracture, the proximal fragment is displaced anterolaterally. This sharp metaphyseal spike places the radial nerve at the greatest risk of injury.

Question 87

A 30-year-old male sustains a vertically oriented, displaced femoral neck fracture (Pauwels type III). What is the primary biomechanical rationale for using a sliding hip screw with a derotation screw rather than three parallel cancellous screws for fixation?

Explanation

Pauwels type III fractures have a high vertical angle, subjecting them to massive shear forces during weight-bearing. A fixed-angle device like a sliding hip screw provides superior resistance to vertical shear compared to multiple cancellous screws.

Question 88

A 55-year-old male presents with deep, aching shoulder pain. Radiographs reveal a large, lytic lesion in the proximal humerus with intralesional 'popcorn' calcifications and endosteal scalloping. What is the most appropriate definitive management for a conventional high-grade lesion of this type?

Explanation

The presentation describes a conventional chondrosarcoma. Unlike osteosarcoma or Ewing sarcoma, conventional chondrosarcomas are generally resistant to chemotherapy and radiation, making wide surgical resection the primary treatment.

Question 89

Which of the following total hip arthroplasty bearing surface combinations has the lowest theoretical volumetric wear rate but carries an inherent risk of squeaking and catastrophic component fracture?

Explanation

Ceramic-on-ceramic bearings offer the lowest volumetric wear rates and no risk of metal ion release. However, their extreme stiffness and brittleness introduce unique complications such as squeaking and catastrophic brittle fracture.

Question 90

A 65-year-old male presents with a clumsy gait, dropping objects, and intrinsic hand muscle wasting. Physical exam reveals hyperreflexia in the lower extremities. Which of the following physical exam findings is highly specific for cervical spondylotic myelopathy at the C5-C6 level?

Explanation

The inverted supinator (brachioradialis) reflex involves paradoxical finger flexion or elbow extension when tapping the brachioradialis tendon. It is a highly specific upper motor neuron sign indicative of cervical myelopathy at C5-C6.

Question 91

In the initial resuscitation of a hemodynamically unstable patient with an anteroposterior compression (APC) pelvic ring injury, what is the correct anatomical landmark for the placement of a circumferential pelvic binder?

Explanation

Pelvic binders must be centered directly over the greater trochanters to effectively close the pelvic ring and reduce internal pelvic volume. Placement higher over the iliac crests is less effective and may paradoxically open the pelvic floor.

Question 92

A 50-year-old diabetic female complains of locking and pain at the base of her right thumb. Examination reveals a palpable nodule over the palmar aspect of the metacarpophalangeal joint. The pathology of this condition primarily involves thickening of which specific pulley?

Explanation

Trigger digit (stenosing tenosynovitis) is caused by a size mismatch between the flexor tendon and the A1 pulley, leading to catching or locking. Surgical release specifically targets the A1 pulley.

Orthopedic Prometric Exam Preparation MCQs - Part 1

Orthopedic Prometric Exam Preparation MCQs - Part 9

Orthopedic Prometric Exam Preparation MCQs - Part 9

Chapter Index