Question 1

When counseling a patient concerning the treatment of an acute Achilles tendon rupture, which of the following is true:

Explanation

This meta-analysis showed: Operative versus nonoperative (pooled rates):

Question 2

Following open repair of an Achilles tendon rupture, which of the following is true:

Explanation

This meta-analysis showed: Postoperative splinting: cast alone compared with cast followed by functional bracing Rerupture Cast alone 5.0% (7/140) (relative risk 2.04) Cast followed by functional bracing 2.3% (3/133) Complications (adhesions, infection, disturbed sensibility): Cast alone 35.7% (50/140) (relative risk 1.88) Cast followed by functional bracing 19.5% (26/133)

Question 3

Which of the following is the most useful symptom or sign of a foot compartment syndrome:

Explanation

Pain out of proportion to injury is the most reliable indicator of a foot compartment syndrome. Foot compartment syndromes can be difficult to diagnose compared to compartment syndromes of the leg. In the leg, one can rely on motor and nerve testing while motor testing in the foot is difficult secondary to the pain from the injury. The severe pain is usually out of proportion to injury. Pain suggestive of compartment syndrome includes: Unremitting pain Pain not responsive to increasing doses of narcotics Pain that is so severe the patient cannot lie still or cooperate with the examiner

Question 4

Which of the following is the most useful sign in diagnosing a foot compartment syndrome:

Explanation

Pain with passive stretch is a reliable sign in compartment syndrome of the leg, foot, and ankle. In Myersonâ s study, he found that pain with passive stretch was present in 86% of patients when those intrinsic muscles of the foot were stretched.

Question 5

Which of the following compartments are most commonly involved (increased tissue pressure) in compartment syndrome of the foot:

Explanation

The calcaneal compartment is most commonly involved in foot compartment syndromes. Approximately 5% to 10% of calcaneus fractures are complicated by a compartment syndrome. The cancellous bone of the calcaneus may have significant bleeding. Swelling of the hindfoot can be severe.

Question 6

Which of the following is the most commonly accepted number of foot compartments:

Explanation

The foot can be divided into nine distinct compartments. A. C alcaneal compartment 1. Quadratus plantae 2. Posterior tibial nerve, artery, and vein 3. Lateral plantar nerve, artery, and vein 4. Medial plantar nerve (variable) *Remember that the calcaneal compartment may communicate with the posterior tibial compartment. A. Interosseiâ (four separate compartments) B. Adductor muscle C . Medial 1. Flexor hallucis brevis 2. Abductor hallucis D. Lateral 1. Abductor digiti minimi 2. Flexor digiti minimi E. Superficial 1. Flexor digitorum brevis 2. Lumbricals (four) 3. Flexor digitorum longus 4. Medial plantar nerve (variable)

Question 7

Which of the following structures is in the calcaneal compartment of the foot:

Explanation

The foot can be divided into nine distinct compartments. A. C alcaneal compartment 1. Quadratus plantae 2. Posterior tibial nerve, artery, and vein 3. Lateral plantar nerve, artery, and vein 4. Medial plantar nerve (variable) *Remember that the calcaneal compartment may communicate with the posterior tibial compartment. B. Interosseiâ (four separate compartments) C . Adductor muscle D. Medial 1. Flexor hallucis 2. Abductor hallucis E. Lateral 1. Abductor digiti minimi 2. Flexor digiti minimi F. Superficial 1. Flexor digitorum brevis 2. Lumbricals (four) 3. Flexor digitorum longus 4. Medial plantar nerve (variable)

Question 8

Which of the following structures is in the medial compartment of the foot:

Explanation

The foot can be divided into nine distinct compartments. A. C alcaneal compartment 1. Quadratus plantae 2. Posterior tibial nerve, artery, and vein 3. Lateral plantar nerve, artery, and vein 4. Medial plantar nerve (variable) *Remember that the calcaneal compartment may communicate with the posterior tibial compartment. B. Interossei (four separate compartments) C . Adductor muscle D. Medial 1. Flexor hallucis 2. Abductor hallucis E. Lateral 1. Abductor digiti minimi 2. Flexor digiti minimi F. Superficial 1. Flexor digitorum brevis 2. Lumbricals (four) 3. Flexor digitorum longus 4. Medial plantar nerve (variable)

Question 9

Which of the following foot compartments communicates with the deep posterior tibial compartment:

Explanation

The foot can be divided into nine distinct compartments. A. C alcaneal compartment 1. Quadratus plantae 2. Posterior tibial nerve, artery, and vein 3. Lateral plantar nerve, artery, and vein 4. Medial plantar nerve (variable) *Remember that the calcaneal compartment may communicate with the posterior tibial compartment. B. Interosseiâ (four separate compartments) C . Adductor muscle D. Medial 1. Flexor hallucis 2. Abductor hallucis E. Lateral 1. Abductor digiti minimi 2. Flexor digiti minimi F. Superficial 1. Flexor digitorum brevis 2. Lumbricals (four) 3. Flexor digitorum longus 4. Medial plantar nerve (variable)

Question 10

A 45-year-old man has severe, unremitting pain after sustaining a displaced calcaneus fracture. He is immobilized in a bulky compression dressing with plaster splints. After removing his dressing, he is noted to have marked swelling with no resolution of his pain. The next step in management is:

Explanation

The patient has the most reliable finding in foot compartment syndromesâ unremitting pain that is out of proportion to injury. When patients have unremitting pain following removal of a compression dressing, the compartment pressures should be measured to determine if a compartment syndrome is present. If the tissue pressure is within 30 mm Hg of the diastolic pressure, the pressures are above 30 mm Hg, and a neurological deficit is present, a compartment syndrome has occurred and the patient should undergo an emergency fasciotomy.

Question 11

A 45-year-old man has severe, unremitting pain after sustaining a displaced calcaneus fracture. His hindfoot is swollen. The calcaneal compartment tissue pressure is 47 mm Hg. His diastolic pressure is 70 mm Hg. The next step in management is:

Explanation

The patient has the most reliable finding in foot compartment syndromesâ unremitting pain that is out of proportion to injury. When patients have unremitting pain following removal of a compression dressing, the compartment pressures should be measured to determine if a compartment syndrome is present. If the tissue pressure is within 30 mm Hg of the diastolic pressure, the pressures are above 30 mm Hg, and a neurological deficit is present, a compartment syndrome has occurred and the patient should undergo an emergency fasciotomy.

Question 12

Which of the following groups of muscles are located in the first layer of the foot muscles:

Explanation

The muscles of the foot and their innervations are as follows: Abbreviations: MPN=medial plantar nerve, LPN=lateral plantar nerve, MTPJ=metatarsophalangeal joint, PIP=proximal interphalangeal joint, and DIP=distal interphalangeal joint.

Question 13

Which of the following muscles are in the second layer of the foot:

Explanation

The muscles of the foot and their innervations are as follows: Abbreviations: MPN=medial plantar nerve, LPN=lateral plantar nerve, MTPJ=metatarsophalangeal joint, PIP=proximal interphalangeal joint, and DIP=distal interphalangeal joint.

Question 14

Which of the following groups of muscles are in the third layer of the foot:

Explanation

The muscles of the foot and their innervations are as follows: Abbreviations: MPN=medial plantar nerve, LPN=lateral plantar nerve, MTPJ=metatarsophalangeal joint, PIP=proximal interphalangeal joint, and DIP=distal interphalangeal joint.

Question 15

Which of the following muscles are innervated by the medial plantar nerve:

Explanation

The muscles of the foot and their innervations are as follows: Abbreviations: MPN=medial plantar nerve, LPN=lateral plantar nerve, MTPJ=metatarsophalangeal joint, PIP=proximal interphalangeal joint, and DIP=distal interphalangeal joint.

Question 16

Which of the following is true of interdigital neuromas:

Explanation

Discussion Important core knowledge of interdigital neuroma (Morton's syndrome) includes: A. Etiology-neither a neuroma nor a tumor; most likely degenerative from repetitive trauma from the transverse intermetatarsal ligament. 1. Pathology-most commonly perineural fibrosis B. Most common in the third web space (about 80%) 1. Medial branch of the lateral plantar nerve joins the lateral branch of medial plantar curve C . More common in women than men D. Presentation 1. Paresthesias, dysesthesias, burning sensation 2. Diffuse symptoms in forefoot 3. Pain is relieved by massaging the foot 4. Numbness occurs as a late finding E. Physical examination 1. Tenderness to direct pressure in the web space 2. Tenderness with forefoot compression

Question 17

Which of the following structures can cause chronic impingement-type posterior ankle pain athletes:

Explanation

Discussion Posterior impingent can be caused by anomalous muscles. The most common is the peroneus quartus. Here are some important points. Posterior ankle impingement-compression of the talus and surrounding soft tissues between the tibia and calcaneus A. C ause-forced or repetitive plantar flexion of the foot B. Occurs in dancers and athletes C . Presentation-pain in the medial or lateral aspect of the ankle posteriorly with activities, especially plantar flexion D. Physical examination-tenderness medial or lateral to the Achilles tendon E. Diagnosis is difficult to make and often missed because of the following: 1. Symptoms are reproduced by plantar flexion of the ankle 2. Injections can be performed to see if the injection relieves the symptoms Anomalous muscles about the ankle A. Most common is the peroneus quartus (prevalence of the muscle between 7% and 22%) 1. Arises from peroneus brevis and inserts into retrotrochlear eminence of the calcaneus B. Peroneocalcaneus internus (1%) 1. Arises from the fibula and inserts into under surface of sustentaculum tali C . Long accessory to the long flexors or quadratus plantae (1%-8%) D. Tibiocalcaneus internus E. Accessory soleus

Question 18

Which of the following may cause impingement-type posterior ankle pain in dancers?

Explanation

Discussion Posterior ankle impingement caused by compression of the talus and surrounding soft tissues between the tibia and calcaneus. In dancers, symptoms may be caused by a low lying or enlarged flexor hallucis longus muscle. A. Cause forced or repetitive plantar flexion of the foot B. Occurs in dancers and athletes C . Presentation â pain in the medial or lateral aspect of the ankle posteriorly with activities, especially plantar flexion D. Physical examination â tenderness medial or lateral to the Achilles tendon E. Diagnosis is difficult to make and often missed 1. Symptoms are reproduced by plantar flexion of the ankle 2. Injections can be performed to see if the injection relieves the symptoms Causes of posterior impingement: A. Os trigonum B. Enlarged lateral process of the talus Enlarged posterior process of the calcaneus Posterior intermalleolar ligament Soft tissue impingement Loose bodies Ganglia Low lying flexor hallucis longus muscle body Anomalous muscle bodies

Question 19

Which of the following statements about the gait cycle is true:

Explanation

Discussion Because gait cycle questions are common on examinations, remember the following points: Stance phase: 62% of cycle Swing phase: 38% of cycle Muscle firing Electromyography findings during gait cycle: Muscle Activity Heel strike Anterior tibialis Gastroc-soleus Eccentric contraction Quiet Foot flat Anterior tibialis Gastroc-soleus Quiet Eccentric contraction Heel-off Gastroc-soleus C oncentric contraction Toe-off Gastroc-soleus C oncentric contraction Subtalar joint Heel strike to foot flat: Three important points Eversion of the subtalar joint Unlocking of the transverse tarsal joint Internal rotation of the tibia Heel rise to toe-off Inversion of the subtalar joint Locking of the transverse tarsal joint External rotation of the tibia

Question 20

Which of the following statements describes the subtalar joint during walking:

Explanation

Discussion Because gait cycle questions are common on examinations, remember these points: Stance phase: 62% of cycle Swing phase: 38% of cycle Muscle firing Electromyography findings during gait cycle: Muscle Activity Heel strike Anterior tibialis Gastroc-soleus Eccentric contraction Quiet Foot flat Anterior tibialis Gastroc-soleus Quiet Eccentric contraction Heel-off Gastroc-soleus C oncentric contraction Toe-off Gastroc-soleus C oncentric contraction Subtalar joint Heel strike to foot flat: Three important points Eversion of the subtalar joint Unlocking of the transverse tarsal joint Internal rotation of the tibia Heel rise to toe-off Inversion of the subtalar joint Locking of the transverse tarsal joint External rotation of the tibia

Question 21

Which of the following tendons is the main inverter of the hind foot:

Explanation

p class="subHeader"> Discussion The posterior tibial tendon is the main inverter of the hindfoot. To conduct a sensitive test for posterior tibial tendon function, ask a patient to perform a single leg rise and observe if the hindfoot inverts. Patients with no posterior tibial tendon function are unable to invert the hindfoot on single leg rise.

Question 22

Slide 1 Slide 2 Slide 3 Slide 4 A 35-year-old woman has a swollen and painful small toe. The radiographs of her foot are shown in Slides 1 and 2, and biopsy specimens in Slides 3 and 4. The most likely diagnosis is:

Explanation

The radiographs show an expansile, lytic destructive lesion, which has replaced the distal and middle phalanxes of the little toe. The biopsy specimen shows the squamous epithelium of the skin with keratin production extending into the medullary cavity of the bone. The patient has an epidermoid inclusion cyst. These cysts are usually secondary to trauma. The treatment should be curettage and grafting.C orrect Answer: Epidermoid inclusion cyst

Question 23

A 35-year-old woman has a swollen and painful small toe. The radiographs of her foot are shown in Slides 1 and 2, and biopsy specimens are shown in Slides 3 and 4. The most appropriate treatment would be:

Explanation

The radiographs show an expansile, lytic destructive lesion, which has replaced the distal and middle phalanxes of the little toe. The biopsy specimen shows the squamous epithelium of the skin with keratin production extending into the medullary cavity of the bone. The patient has an epidermoid inclusion cyst. These cysts are usually secondary to trauma. The treatment should be curettage and grafting. Orthopedic Prometric Exam Question

Question 24

Which of the following statements about plantar fasciitis is true:

Explanation

Discussion Plantar fasciitis: General features Most common cause of heel pain Frequently occurs in athletes Men and women affected equally Symptoms are bilateral in 10% of patients C linical findings Pain on the bottom of the heel Pain is worse with first steps in the morning Pain is worse with weight bearing after sitting Pain is worse with activities of daily living Tenderness over the plantar fascia Pain is worsened by dorsiflexion of the toes Plantar fascia Broad, thick structure that originates from the medial calcaneal tuberosity and inserts on the plantar plates of the metatarsalphalangeal joints and proximal phalanges Supports the medial longitudinal arch Although the etiology of plantar fasciitis is not known, one theory is excessive stress on the plantar fascia causes micro tears Biopsies show fibroblastic proliferation and chronic granulomatous tissue The fascia can be as thick as 15 mm (3 mm is normal)

Question 25

Which of the following statements describes the results of extracorporeal shock wave therapy for chronic plantar fasciitis:

Explanation

Discussion In a recent study in Orthopaedics, Furia showed that a significant improvement in pain and function scores occurred in patients who had plantar fasciitis treated with extracorporeal shock wave therapy. Approximately 80% of the patients were satisfied with the treatment and would have the shock wave treatment again. Results Pain Visual Analog Scale (VAS) Pre-treatment VAS 9.2 standard deviation (SD) 0.7 Post-treatment VAS (4 weeks) 3.4 SD 1.9 (P<.05) Post-treatment VAS (12 weeks) 2.4 SD dev 1.8 (P<.05) RAND Score Physical functioning Pre-treatment 40.4 SD 1.3 Post-treatment (4 weeks) 91.5 SD 11.5 (P<.05) Post-treatment (12 weeks) 91.5 SD 10.6 (P<.05) RAND Score Pain Pre-treatment 3.3 SD dev 1.1 Post-treatment (4 weeks) 88.6 SD 16 (P<.05) Post-treatment (12 weeks) 90.0 SD 11.6 (P<.05) Patient satisfaction At 4 and 12 weeks post treatment, 49 (82%) patients were satisfied, and all patients would undergo the procedure again.

Question 26

A 40-year-old man has pain in his foot after minor trauma. A radiograph is shown in Slide 1 and biopsy specimens are shown in Slides 2 and 3. The most likely diagnosis is:

Explanation

The radiograph shows a lucent lesion in the proximal phalanx of the second toe and expansion of the proximal phalanx. The bone is expanded with a thin periosteal rim. Faint calcifications are also seen within the medullary cavity. This radiographic appearance is characteristic of an enchondroma. The low-power hematoxylin and eosin stain shows abundant blue hyaline matrix and a paucity of cells. The high-power hematoxylin and eosin stain shows the small dark and uniform nuclei present in enchondromas. No pleomorphism or nuclear atypia are present.

Question 27

A 40-year-old man has pain in his foot after minor trauma. A radiograph is shown in Slide 1 and biopsy specimens are shown in Slides 2 and 3. Which of the following would be the most appropriate treatment:

Explanation

The radiograph shows a lucent lesion in the proximal phalanx of the second toe and expansion of the proximal phalanx. The bone is expanded with a thin periosteal rim. Faint calcifications are also seen within the medullary cavity. This radiographic appearance is fairly characteristic of an enchondroma. The low-power hematoxylin and eosin stain shows abundant blue hyaline matrix and a paucity of cells. The high-power hematoxylin and eosin stain shows the small dark and uniform nuclei present in enchondromas. No pleomorphism or nuclear atypia are present. Orthopedic Prometric Exam Question

Question 28

A 40-year-old man has pain in his foot after minor trauma. A radiograph is shown in Slide 1 and biopsy specimens are shown in Slides 2 and 3. Which of the following best describes this condition:

Explanation

The radiograph shows a lucent lesion in the proximal phalanx of the second toe and expansion of the proximal phalanx. The bone is expanded with a thin periosteal rim. Faint calcifications are also seen within the medullary cavity. This radiographic appearance is fairly characteristic of an enchondroma. The low-power hematoxylin and eosin stain shows abundant blue hyaline matrix and a paucity of cells. The high-power hematoxylin and eosin stain shows the small dark and uniform nuclei present in enchondromas. No pleomorphism or nuclear atypia are present.

Question 29

A 35-year-old man has experienced foot pain for 6 months. The anteroposterior and oblique radiographs are shown in Slides 1 and 2, and a biopsy specimen is shown in Slide 3. The most likely diagnosis is:

Orthopedic Prometric Exam Question

Explanation

The radiographs show lytic destructive lesions in the first and second metatarsals. Malignant vascular tumors, such as hemangioendothelioma, characteristically manifest as multiple lytic lesions in the same extremity in young patients. The biopsy shows vasoformative cells, which are trying to form blood vessels. The correct diagnosis is hemangioendothelioma of bone, which is a low-grade malignancy with a low risk of pulmonary metastases. Patients are typically treated with external beam irradiation. This patient opted for below-knee amputation. He could have also been treated with irradiation.

Question 30

A 35-year-old man has foot pain for 6 months. The anteroposterior and oblique radiographs are shown in Slides 1 and 2, and a biopsy specimen is shown in Slide 3. Which of the following treatments is the most appropriate:

Explanation

The radiographs show lytic destructive lesions in the first and second metatarsals. Malignant vascular tumors, such as hemangioendothelioma, characteristically manifest as multiple lytic lesions in the same extremity in young patients. The biopsy shows vasoformative cells, which are trying to form blood vessels. The correct diagnosis is hemangioendothelioma of bone, which is a Orthopedic Prometric Exam Question

low-grade malignancy with a low risk of pulmonary metastases. Patients are typically treated with external beam irradiation. This patient opted for below-knee amputation. He could have also been treated with irradiation.

Question 31

A 35-year-old man has foot pain for 6 months. The anteroposterior and oblique radiographs are shown in Slides 1 and 2, and a biopsy specimen is shown in Slide 3. The etiology of this condition is most likely:

Explanation

The radiographs show lytic destructive lesions in the first and second metatarsals. Malignant vascular tumors, such as hemangioendothelioma, characteristically manifest as multiple lytic lesions in the same extremity in young patients. The biopsy shows vasoformative cells, which are trying to form blood vessels. The correct diagnosis is hemangioendothelioma of bone, which is a low-grade malignancy with a low risk of pulmonary metastases. Patients are typically treated with external beam irradiation. This patient opted for below-knee amputation. He could have also been treated with irradiation.

Question 32

Which of the following medications is an effective alternative to intravenous vancomycin for the treatment of severe soft tissue infections caused by methicillin-resistant Staphylococcus aureus (MRSA):

Explanation

Oral linezolid (600 mg twice a day) is an effective oral alternative to intravenous vancomycin. Below is a summary of a recent prospective, randomized study showing the efficacy of linezolid. Staphylococcus aureus complicates soft tissue and skin infections. Approximately 30% of S aureus infections are methicillinresistant. Although vancomycin has been the treatment of choice for MRSA, linezolid inhibits bacterial protein synthesis by blocking formation of the 70S initiation complex and can be administered orally, which is an advantage over vancomycin. This is a single-center study of adult patients. Investigators randomized 60 patients with S aureus (culture proven) to intravenous vancomycin or oral linezolid. The median length of therapy was 10 days. Seven patients in the vancomycin group required amputation, whereas no amputations were performed in the linezolid group. The median length of hospital stay was shorter in the linezolid group, and outpatient therapy was $100 per day less expensive (approximately $6,500 was saved on the hospital stay). A higher clinical cure rate (94%) was reported with the linezolid group compared to 84% with vancomycin. Linezolid is given orally, 600 mg every 12 hours, and it is well tolerated. No adverse effects were reported in this study. Other studies have had similar results. This is an important study for orthopedic surgeons because the number of patients presenting with MRSA infections is increasing. Athletes may be at an increased risk for the infection because of the potential for spread in locker rooms. This can be a limb-threatening infection and must be taken seriously.

Question 33

The mechanism of action of linezolid is:

Explanation

Oral linezolid (600 mg twice a day) is an effective oral alternative to intravenous vancomycin. Below is a summary of a recent prospective, randomized study showing the efficacy of linezolid. Staphylococcus aureus complicates soft tissue and skin infections. Approximately 30% of S aureus infections are methicillinresistant. Although vancomycin has been the treatment of choice for methicillin- resistant S aureus (MRSA), linezolid inhibits bacterial protein synthesis by blocking formation of the 70S initiation complex and can be administered orally, which is an advantage over vancomycin. This is a single-center study of adult patients. Investigators randomized 60 patients with S aureus (culture proven) to intravenous vancomycin or oral linezolid. The median length of therapy was 10 days. Seven patients in the vancomycin group required amputation, whereas no amputations were performed in the linezolid group. The median length of hospital stay was shorter in the linezolid group, and outpatient therapy was $100 per day less expensive (approximately $6,500 was saved on the hospital stay). A higher clinical cure rate (94%) was reported with the linezolid group compared to 84% with vancomycin. Linezolid is given orally, 600 mg every 12 hours, and it is well tolerated. No adverse effects were reported in this study. Other studies have had similar results. This is an important study for orthopedic surgeons because the number of patients presenting with MRSA infections is increasing. Athletes may be at an increased risk for the infection because of the potential for spread in locker rooms. This can be a limb-threatening infection and must be taken seriously.

Question 34

A 25-year-old minor league baseball player has a severe soft tissue infection on the sole of his foot. The infection has not responded to oral cephalexin. There is 4 cm of surrounding erythema and induration, and a small amount of exudate can be expressed. The most likely organism is:

Explanation

Staphylococcus aureus complicates soft tissue and skin infections. Approximately 30% of S aureus infections are methicillinresistant. Although vancomycin has been the treatment of choice for MRSA, linezolid inhibits bacterial protein synthesis by blocking formation of the 70S initiation complex and can be administered orally, which is an advantage over vancomycin. This is a single-center study of adult patients. Investigators randomized 60 patients with S aureus (culture proven) to intravenous vancomycin or oral linezolid. The median length of therapy was 10 days. Seven patients in the vancomycin group required amputation, whereas no amputations were performed in the linezolid group. The median length of hospital stay was shorter in the linezolid group, and outpatient therapy was $100 per day less expensive (approximately $6,500 was saved on the hospital stay). A higher clinical cure rate (94%) was reported with the linezolid group compared to 84% with vancomycin. Linezolid is given orally, 600 mg every 12 hours, and it is well tolerated. No adverse effects were reported in this study. Other studies have had similar results. This is an important study for orthopedic surgeons because the number of patients presenting with MRSA infections is increasing. Athletes may be at an increased risk for the infection because of the potential for spread in locker rooms. This can be a limb-threatening infection and must be taken seriously.

Question 35

A 15-year-old boy has a large mass underneath the toenail of his great toe. His nail is raised and ulceration is present. The plain radiograph is shown in Slide 1, and biopsy specimens are shown in Slides 2, 3, and 4. The most likely diagnosis is:

Explanation

The plain radiograph shows a large bone lesion arising from the dorsal surface of the distal phalanx. This radiographic appearance is characteristic of a subungual exostosis. Osteochondromas do not occur in the distal phalanx, and there is no communication between the lesion and the medullary cavity. Orthopedic Prometric Exam Question

The biopsy specimens show the new bone formation and a fibroblastic stroma, which can be confused with osteosarcoma. The diagnosis is subungual exostosis and the treatment is simple excision.

Question 36

A 15-year-old boy has a large mass underneath the toenail of his great toe. His nail is raised and ulceration is present. The plain radiograph is shown in Slide 1, and biopsy specimens are shown in Slides 2, 3, and 4. Which of the following is the best form o treatment:

Explanation

The plain radiograph shows a large bone lesion arising from the dorsal surface of the distal phalanx. This radiographic appearance is characteristic of a subungual exostosis. Osteochondromas do not occur in the distal phalanx, and there is no communication between the lesion and the medullary cavity. The biopsy specimens show the new bone formation and a fibroblastic stroma, which can be confused with osteosarcoma. The diagnosis is subungual exostosis and the treatment is simple excision.

Question 37

A 15-year-old boy has a large mass underneath the toenail of his great toe. His nail is raised and ulceration is present. The plain radiograph is shown in Slide 1, and biopsy specimens are shown in Slides 2, 3, and 4. Which of the following best describes this condition:

Explanation

The plain radiograph shows a large bone lesion arising from the dorsal surface of the distal phalanx. This radiographic appearance is characteristic of a subungual exostosis. Osteochondromas do not occur in the distal phalanx, and there is no communication between the lesion and the medullary cavity. Orthopedic Prometric Exam Question

The biopsy specimens show the new bone formation and a fibroblastic stroma, which can be confused with osteosarcoma. The diagnosis is subungual exostosis and the treatment is simple excision.

Question 38

Deep infection following open reduction internal fixation (ORIF) for tibial pilon fractures is most commonly associated with:

Explanation

Deep infection following ORIF of pilon fractures is correlated with postoperative wound dehiscence or skin slough but not with the presence of an open fracture in a series of 60 pilon fractures treated by ORIF.

Question 39

Polyglycolide screws used for fixation of ankle fractures:

Explanation

Polyglycolide screws have a high incidence of sterile effusions as a result of rapid hydrolysis; polylactide screws showed no soft tissue reactions.

Question 40

The most effective fixation technique that will ensure adequate visualization (imaging) of avascular necrosis changes following talar neck fracture is:

Explanation

High-quality magnetic resonance images of the talus can consistently be obtained in the presence of titanium screws in contrast to images obtained with stainless steel implants. Magnetic resonance imaging is better than plain radiographs at assessing the volume of talar avascular necrosis.

Question 41

Treatment of significant loss of height and posttraumatic arthritis following nonoperative treatment of calcaneus fractures should include:

Explanation

Management of late loss of height following calcaneus fracture is best addressed by a distraction arthrodesis of the subtalar joint using a wedge- shaped structural bone graft.

Question 42

Incisions made through blood-filled fracture blisters have:

Explanation

Biopsies of the edge of fracture blisters following ankle fracture show that blood-filled blisters represent a deeper injury than clear fluid-filled blisters. The dermis of clear blisters still showed some epithelial cells remaining, while the dermis of blood blisters showed no epithelial cells. Therefore, blood-filled blisters are more difficult to heal.

Question 43

The plantar ecchymosis sign is:

Explanation

The plantar ecchymosis sign is described as an ecchymotic area on the plantar midfoot that is indicative of possible injury to the plantar tarsometatarsal ligaments.

Question 44

The joint contact area of the second tarsometatarsal joint after Lisfranc dislocation diminishes the greatest with:

Explanation

Minor degrees of displacement not apparent on plain radiographs lead to significant decrease in the contact area of the second tarsometatarsal joint. Dorsolateral subluxation of the second tarsometatarsal joint suffers a loss of contact area more severely than pure dorsal or lateral subluxation. Just 3 mm of dorsolateral subluxation causes a 38% loss of contact area.

Question 45

The â fleck signâ in midfoot injuries is a result of avulsion of the:

Explanation

The fleck sign was described as an avulsion of the ligament that runs from the medial cuneiform to the base of the second metatarsal, the so-called Lisfranc ligament. It is considered pathognomonic for a tarsometatarsal injury.

Question 46

Delayed unions and nonunions of base of fifth metatarsal fractures have been demonstrated to heal by:

Explanation

Nine delayed unions and nonunions of the proximal fifth metatarsal were treated with pulsed electromagnetic fields. All fractures healed in a mean of 4 months (follow-up 39 months, no refractures).

Question 47

The main blood supply to the talar body is from the:

Explanation

The main blood supply to the body of the talus is the artery of the tarsal canal, which is a branch off the posterior tibial artery. The dorsalis pedis and the artery of the sinus tarsi supply the talar head.

Question 48

The strongest hardware configuration for fixation of talar neck fractures is:

Explanation

Biomechanical cadaveric testing of several screw configurations showed two parallel screws from proximal to distal as the strongest fixation. The screws can be inserted either open or percutaneously. All screw configurations were stronger than K-wire configurations.

Question 49

The maximal joint reactive force in the ankle is approximately:

Explanation

Stauffer and colleagues quantified ankle joint reactive force to be approximately 5 times body weight. This is a significant concern for prosthetic ankle arthroplasty because the implant surface area is relatively small over which these forces must be spread out.

Question 50

According to Sandersâ computed tomography (C T) classification for calcaneus fractures, a Sanders III fracture has:

Explanation

The Sanders C T classification is determined on coronal C T scans of the calcaneus at the level where the posterior facet is widest. A Sanders I is a nondisplaced fracture; Sanders II consists of a single fracture line splitting the posterior facet into two main fragments; Sanders III has two fracture lines with three main posterior facet fragments; and a Sanders IV has four or more articular fragments present.

Question 51

A 30-year-old male sustains a Hawkins Type II fracture of the talar neck following a motor vehicle collision. Which of the following accurately describes the joint dislocation and the associated risk of avascular necrosis (AVN)?

Explanation

A Hawkins Type II fracture involves a talar neck fracture with subluxation or dislocation of the subtalar joint. The risk of AVN in Type II fractures is classically reported as 20% to 50%.

Question 52

Which of the following measurements is the most reliable threshold for diagnosing an acute compartment syndrome of the lower extremity requiring fasciotomy?

Explanation

Delta pressure (diastolic blood pressure minus compartment pressure) of less than 30 mmHg is the most reliable indicator for diagnosing acute compartment syndrome and indicates the need for emergent fasciotomy.

Question 53

When evaluating a patient after a traumatic anterior shoulder dislocation, which of the following is the single greatest risk factor for recurrent instability?

Explanation

The patient's age at the time of the first dislocation is the most significant prognostic factor for recurrence. Patients under 20 years old have a recurrence rate often exceeding 80%.

Question 54

In the Ponseti method for the treatment of idiopathic clubfoot, what is the correct sequential order of deformity correction?

Explanation

The Ponseti method utilizes the CAVE sequence: Cavus (by elevating the first ray), Adductus, Varus, and finally Equinus (which often requires a percutaneous Achilles tenotomy).

Question 55

The direct anterior approach to the hip for total hip arthroplasty utilizes a true internervous plane. Which two muscles define this superficial surgical interval?

Explanation

The superficial internervous plane for the direct anterior (Smith-Petersen) approach is between the tensor fasciae latae (superior gluteal nerve) and the sartorius (femoral nerve).

Question 56

A 22-year-old male presents with a proximal pole scaphoid fracture. The high risk of avascular necrosis in this region is primarily due to the retrograde blood supply from which vessel?

Explanation

The scaphoid receives its primary blood supply from the dorsal carpal branch of the radial artery, which enters distally and flows retrograde to the proximal pole, making proximal fractures prone to AVN.

Question 57

A 35-year-old female is diagnosed with a giant cell tumor of the distal femur. If medical therapy is considered for an unresectable lesion, denosumab may be used. What is the mechanism of action of denosumab?

Explanation

Denosumab is a fully human monoclonal antibody that binds to Receptor Activator of Nuclear factor Kappa-B Ligand (RANKL), preventing it from activating RANK on the surface of osteoclasts, thereby inhibiting bone resorption.

Question 58

A 45-year-old sustains a Hangman's fracture demonstrating severe angulation but minimal translation, classified as an Effendi/Levine-Edwards Type IIa. What is the appropriate initial management strategy?

Explanation

Type IIa Hangman's fractures involve an atypical flexion-distraction injury. Cervical traction is contraindicated as it will worsen the deformity; management requires gentle compression and extension in a halo vest.

Question 59

A 68-year-old female on long-term bisphosphonate therapy presents with a non-traumatic thigh ache. Radiographs reveal an incomplete atypical femoral fracture. Where does the cortical thickening and fracture initiation typically occur in these injuries?

Explanation

Atypical femur fractures associated with prolonged bisphosphonate use characteristically originate at the lateral cortex (the tension side) with localized periosteal thickening and a transverse or short oblique fracture pattern.

Question 60

During surgical reconstruction of a Lisfranc injury, the surgeon must identify and recreate the Lisfranc ligament complex. Which of the following describes the anatomical attachments of the primary Lisfranc ligament?

Explanation

The Lisfranc ligament is an intra-articular ligament that runs from the lateral aspect of the medial cuneiform to the medial base of the second metatarsal.

Question 61

A 6-year-old child sustains a severely displaced extension-type supracondylar fracture of the humerus. Which nerve is most commonly injured in this specific fracture pattern?

Explanation

The anterior interosseous nerve (AIN), a branch of the median nerve, is the most commonly injured nerve in extension-type supracondylar humerus fractures due to the anterior displacement of the proximal fracture fragment.

Question 62

According to the Young-Burgess classification, an Anteroposterior Compression Type II (APC-II) pelvic ring injury is characterized by which of the following ligamentous disruptions?

Explanation

An APC-II injury is an "open book" pelvic fracture where the pubic symphysis is widened, the sacrotuberous/sacrospinous and anterior sacroiliac ligaments are disrupted, but the stout posterior sacroiliac ligaments remain intact.

Question 63

Which of the following best describes the biomechanical consequence of an untreated posterior medial meniscal root tear?

Explanation

A posterior meniscal root tear disrupts the ability of the meniscus to convert axial loads into hoop stresses, resulting in a biomechanical state equivalent to a total meniscectomy and leading to rapid articular degeneration.

Question 64

During a primary total knee arthroplasty, the surgeon assesses the gaps with trial components. The extension gap is found to be symmetrically tight, while the flexion gap is well-balanced. What is the most appropriate next step to balance the knee?

Explanation

A tight extension gap with a balanced flexion gap indicates that the distal femoral cut is insufficient. Resecting more distal femur will increase the extension gap without affecting the flexion gap.

Question 65

A 55-year-old diabetic patient presents with severe back pain, fever, and progressive lower extremity weakness. MRI reveals a spinal epidural abscess. What is the most common causative organism?

Explanation

Staphylococcus aureus is by far the most common organism responsible for spinal epidural abscesses and vertebral osteomyelitis in the general population.

Question 66

A 60-year-old female complains of medial ankle pain and a progressively flattening arch. On examination, she is diagnosed with Stage II adult acquired flatfoot deformity (posterior tibial tendon dysfunction). Which clinical finding is characteristic of Stage II?

Explanation

Stage II posterior tibial tendon dysfunction is characterized by a visible flatfoot deformity with a flexible hindfoot valgus, forefoot abduction, and the clinical inability to perform a single-leg heel rise.

Question 67

Recombinant human bone morphogenetic protein-2 (rhBMP-2) is utilized in orthopedic surgery to promote bone healing. According to the FDA, which of the following is an approved indication for the use of rhBMP-2?

Explanation

rhBMP-2 is currently FDA-approved for single-level anterior lumbar interbody fusion (ALIF) using an LT-CAGE device, as well as for acute, open tibial shaft fractures treated with an intramedullary nail.

Question 68

A patient presents with a vague proximal forearm ache and weakness in the hand. The surgeon suspects anterior interosseous nerve (AIN) syndrome. Which of the following physical examination findings is most specific for this diagnosis?

Explanation

AIN syndrome results in motor weakness of the flexor pollicis longus (FPL), the flexor digitorum profundus (FDP) to the index/middle fingers, and the pronator quadratus. This classically presents as the inability to form an "OK" sign.

Question 69

A 35-year-old male sustains a pronation-external rotation ankle fracture. Following ORIF of the fibula, the syndesmosis remains unstable. Which of the following is true regarding syndesmotic screw fixation?

Explanation

Studies show no significant difference in clinical outcomes whether syndesmotic screws are removed, retained, or broken. Routine removal is not indicated unless the hardware is symptomatic. Flexible fixation has shown comparable or slightly better functional outcomes than rigid screws.

Question 70

A 6-year-old boy presents with a completely displaced extension-type supracondylar humerus fracture. On examination, he is unable to flex the interphalangeal joint of his thumb and the distal interphalangeal joint of his index finger. What is the most likely injured nerve?

Explanation

The anterior interosseous nerve (AIN) is a motor branch of the median nerve that innervates the FPL, FDP to the index/middle fingers, and pronator quadratus. It is the most commonly injured nerve in extension-type pediatric supracondylar humerus fractures.

Question 71

A 55-year-old active male underwent a total hip arthroplasty with a ceramic-on-ceramic bearing surface 3 years ago. He now complains of a high-pitched squeaking noise during activity. Which of the following factors is most strongly associated with this complication?

Explanation

Squeaking in ceramic-on-ceramic total hip arthroplasty is highly associated with edge loading. This is often caused by acetabular cup malposition (such as excessive anteversion or steep inclination), leading to abnormal wear patterns and microseparation.

Question 72

A 68-year-old male presents with neurogenic claudication. Which of the following history or physical examination findings most reliably differentiates neurogenic claudication from vascular claudication?

Explanation

Walking uphill induces lumbar flexion, which increases the spinal canal cross-sectional area and relieves symptoms in neurogenic claudication. Conversely, vascular claudication worsens with increased exertion like walking uphill and resolves quickly when the patient stands still.

Question 73

A 24-year-old athlete presents with chronic radial-sided wrist pain. Radiographs reveal a scaphoid nonunion advanced collapse (SNAC) pattern with arthritis involving the radioscaphoid and capitolunate joints, but sparing the radiolunate joint. What is the most appropriate surgical treatment?

Explanation

In stage II or III SNAC/SLAC wrist, the capitolunate joint is arthritic, making a proximal row carpectomy contraindicated since it relies on a healthy capitate articular surface. Scaphoid excision with four-corner fusion preserves the healthy radiolunate joint while effectively addressing the arthritic midcarpal segments.

Question 74

During an anterior cruciate ligament (ACL) reconstruction using a bone-patellar tendon-bone (BTB) autograft, the surgeon must be aware of the biomechanical properties of the graft. Which of the following is true regarding a 10 mm BTB autograft compared to the native ACL?

Explanation

A 10 mm central third BTB autograft is biomechanically stronger and stiffer than the native ACL, possessing about 168% of the native ACL's ultimate tensile load. It heals via rapid bone-to-bone healing, typically around 6 weeks, which is faster than soft-tissue grafts.

Question 75

In the setting of a polytraumatized patient with an Injury Severity Score (ISS) of 36, severe closed head injury, and a closed femoral shaft fracture, which of the following is the most appropriate initial management for the femur?

Explanation

In a borderline or unstable polytrauma patient with a severe traumatic brain injury, Damage Control Orthopedics (DCO) is indicated. External fixation provides rapid stability without the physiologic "second hit" and increased intracranial pressure associated with prolonged surgery or canal reaming.

Question 76

A 12-year-old boy presents with knee pain and a destructive, permeative diaphyseal lesion in the femur with a large soft tissue mass. Biopsy reveals small round blue cells. Which chromosomal translocation is most characteristic of this tumor?

Explanation

The scenario describes Ewing sarcoma, characterized by a permeative diaphyseal lesion and small round blue cells on histology. The classic chromosomal translocation is t(11;22)(q24;q12), which results in the EWS-FLI1 fusion protein.

Question 77

A 25-year-old male sustains a twisting injury to his midfoot. Weight-bearing radiographs demonstrate a 3 mm diastasis between the base of the first and second metatarsals. What is the primary stabilizing structure of this interval?

Explanation

The Lisfranc ligament is the strongest restraint to lateral displacement of the lesser metatarsals. It originates from the lateral plantar aspect of the medial cuneiform and inserts onto the medial plantar aspect of the base of the second metatarsal. There is no direct intermetatarsal ligament between the 1st and 2nd metatarsal bases.

Question 78

A 70-year-old female presents with pseudoparalysis of the shoulder. Imaging reveals a massive, irreparable rotator cuff tear involving the supraspinatus and infraspinatus with superior migration of the humeral head, but an intact subscapularis and functioning deltoid. What is the most reliable surgical option to restore active forward elevation?

Explanation

In an elderly patient with pseudoparalysis and a massive irreparable rotator cuff tear (rotator cuff arthropathy), reverse total shoulder arthroplasty is the most reliable procedure to restore forward elevation. It biomechanically medializes the center of rotation and increases the lever arm of the deltoid.

Question 79

A 13-year-old obese male is diagnosed with a stable slipped capital femoral epiphysis (SCFE) of the left hip. Under what circumstance is prophylactic pinning of the contralateral right hip most strongly indicated?

Explanation

Prophylactic pinning of the contralateral hip is highly recommended in patients with endocrine disorders (e.g., hypothyroidism) or metabolic bone diseases (e.g., renal osteodystrophy). These underlying conditions significantly increase the risk of bilateral and sequential involvement.

Question 80

Which of the following ligaments is most critical for the primary stability of the tarsometatarsal joint complex (Lisfranc joint), connecting two specific osseous structures?

Explanation

The Lisfranc ligament is a strong interosseous ligament that connects the lateral aspect of the medial cuneiform to the medial base of the second metatarsal. It is the thickest and most critical stabilizing structure of the midfoot tarsometatarsal complex.

Question 81

A 25-year-old male presents with a closed, highly comminuted tibial shaft fracture following a motorcycle accident. Which of the following is the most sensitive and earliest clinical sign of developing acute compartment syndrome?

Explanation

Pain out of proportion to the injury and pain with passive muscle stretch are the earliest and most sensitive clinical indicators of acute compartment syndrome. Pulselessness, pallor, and paralysis are late, often irreversible signs.

Question 82

According to the Hawkins classification of talar neck fractures, a Type III fracture is characterized by which of the following dislocation patterns?

Explanation

A Hawkins Type III talar neck fracture involves a displaced fracture of the talar neck with subluxation or dislocation of both the subtalar and tibiotalar (ankle) joints. This pattern carries a very high risk of avascular necrosis.

Question 83

In a patient with an intra-articular calcaneus fracture, the Sanders classification system is most heavily based on the fracture pattern seen on which of the following imaging modalities and planes?

Explanation

The Sanders classification system is based on the number and location of articular fracture lines extending through the posterior facet of the calcaneus. These fracture lines are best visualized on coronal CT images.

Question 84

A 55-year-old diabetic patient presents with a red, warm, and severely swollen foot. Radiographs reveal extensive periarticular bone fragmentation, joint subluxation, and intra-articular debris. According to the Eichenholtz classification of Charcot arthropathy, what stage does this represent?

Explanation

Eichenholtz Stage 1 (Developmental) is characterized clinically by an erythematous, edematous foot and radiographically by bone fragmentation, joint subluxation, and periarticular debris. Stage 2 involves coalescence with absorption of fine debris, while Stage 3 shows remodeling.

Question 85

A 22-year-old professional athlete sustains an acute fracture at the metaphyseal-diaphyseal junction of the fifth metatarsal (Jones fracture). Why is this specific fracture pattern uniquely prone to delayed union and nonunion?

Explanation

A true Jones fracture occurs at the metaphyseal-diaphyseal junction, representing a vascular watershed zone. The nutrient artery supplies this diaphyseal region in a retrograde fashion, making the area highly susceptible to ischemia and nonunion.

Question 86

A 40-year-old male sustains a severe high-energy closed tibial pilon fracture. Examination reveals significant soft tissue swelling and multiple fracture blisters. What is the most widely accepted initial management strategy?

Explanation

High-energy pilon fractures are associated with severe soft tissue compromise. The standard of care involves a two-stage approach: initial application of a spanning external fixator, followed by definitive ORIF at a later date once soft tissue swelling has subsided (wrinkle sign present).

Question 87

When planning surgical correction for hallux valgus, a patient presents with a hallux valgus angle (HVA) of 38 degrees and an intermetatarsal angle (IMA) of 18 degrees. Which of the following procedures is most appropriate to predictably correct this deformity?

Explanation

An intermetatarsal angle (IMA) greater than 13-15 degrees constitutes a severe deformity requiring a proximal metatarsal osteotomy (e.g., crescentic or Ludloff) or a first tarsometatarsal fusion (Lapidus procedure). Distal osteotomies are generally insufficient for an IMA of 18 degrees.

Question 88

A 60-year-old overweight female presents with medial foot pain and a progressive flatfoot deformity. Which of the following physical examination findings is most specific for stage II posterior tibial tendon insufficiency?

Explanation

In Stage II posterior tibial tendon dysfunction, the tendon is ruptured or incompetent, clinically manifesting as an inability to perform a single-limb heel rise. The deformity remains flexible in Stage II, whereas it becomes rigid in Stage III.

Question 89

During the radiographic evaluation of an acute ankle injury, which of the following findings on standard plain radiographs is considered the most reliable indicator of a distal tibiofibular syndesmotic disruption?

Explanation

A tibiofibular clear space greater than 5-6 mm on either the AP or mortise radiograph is the most reliable radiographic indicator of syndesmotic injury. Normal tibiofibular overlap should be >1 mm on the mortise view and >6 mm on the AP view.

Orthopedic Prometric Exam Preparation MCQs - Part 1

Orthopedic Prometric Exam Preparation MCQs - Part 5

Orthopedic Prometric Exam Preparation MCQs - Part 5

Chapter Index