Trauma Practice Questions

Q: What type of Monteggia fracture is commonly associated with nerve injuries?

Type II. **Explanation:** The **Monteggia fracture-dislocation** is classified using the **Bado Classification**, which is based on the direction of the radial head dislocation. **Why Type II is correct:** Bado Type II involves a fracture of the ulnar shaft with **posterior or posterolateral dislocation** of the radial head. This specific subtype is most commonly associated with nerve injuries, specifically the **Posterior Interosseous Nerve (PIN)**, a branch of the radial nerve. The mechanism involves the radial head being displaced posteriorly, where it directly compresses or stretches the PIN as it passes through the supinator muscle (Arcade of Frohse). This is particularly common in adults. **Analysis of Incorrect Options:** * **Type I (Anterior):** The most common type overall (especially in children). The radial head dislocates anteriorly. While nerve injuries can occur, they are statistically less frequent than in Type II. * **Type III (Lateral):** Involves ulnar metaphyseal fractures with lateral radial head dislocation. This is more common in the pediatric population and is less frequently associated with nerve palsy compared to Type II. * **Type IV:** Involves fractures of both the radius and ulnar shafts with anterior dislocation of the radial head. It is rare and complex, but Type II remains the classic association for nerve injury in exams. **Clinical Pearls for NEET-PG:** * **Nerve involved:** Posterior Interosseous Nerve (PIN). Note that PIN injury causes **finger drop** (loss of MCP extension) but **no sensory loss**. * **Management:** Most PIN injuries are neuropraxias; hence, observation for 2–3 months is usually recommended before considering exploration. * **Mnemonic (MUGR):** **M**onteggia: **U**lna fracture; **G**aleazzi: **R**adius fracture.

Q: Which of the following is NOT relevant in the management of compartment syndrome?

Exercise. **Explanation:** Compartment syndrome is a surgical emergency characterized by increased pressure within a closed osteofascial space, leading to impaired local circulation and potential tissue necrosis. **Why Exercise is NOT relevant:** **Exercise** is contraindicated in the acute phase of compartment syndrome. Physical activity increases metabolic demand and blood flow to the muscles, which further elevates intracompartmental pressure and exacerbates ischemia. Management focuses on **reducing** pressure, not increasing muscle activity. **Analysis of other options:** * **Fasciotomy:** This is the definitive surgical treatment. It involves incising the fascia to decompress the compartment and restore distal perfusion. * **Splitting of a tight cast:** This is the immediate first step in management. Removing or "bivalving" a restrictive cast/dressing can reduce intracompartmental pressure by up to 30–65%. * **Reexploration:** After a fasciotomy, the wound is left open and requires reexploration (usually within 48–72 hours) for debridement of necrotic tissue and eventual closure or skin grafting. **Clinical Pearls for NEET-PG:** * **Earliest Sign:** Pain out of proportion to the injury and pain on passive stretching of muscles. * **Late Sign:** Pulselessness (indicates irreversible damage; do not wait for this to diagnose). * **Pressure Threshold:** A Delta pressure ($\Delta P$) of **$\leq$ 30 mmHg** (Diastolic BP minus Compartment Pressure) is often used as an indication for fasciotomy. * **Positioning:** Keep the limb at the **level of the heart**. Elevating the limb above the heart reduces arterial inflow and worsens ischemia.

Q: What is commonly referred to as a Potts fracture?

Bimalleolar ankle fracture. **Explanation:** **Potts fracture** (also known as Dupuytren’s fracture) is a classic eponym used to describe a **bimalleolar ankle fracture**. It occurs due to a combination of abduction and external rotation forces at the ankle joint. In this injury, there is typically a fracture of the lateral malleolus (fibula) above the syndesmosis and a fracture of the medial malleolus (tibia) or a tear of the deltoid ligament. This disruption compromises the "ankle mortise," leading to joint instability. **Analysis of Options:** * **Option A (Correct):** Percivall Potts originally described this as a bimalleolar injury. It is the standard definition used in orthopaedic examinations. * **Option B:** A **Trimalleolar fracture** (Cotton’s fracture) involves the medial malleolus, lateral malleolus, and the posterior malleolus (posterior lip of the tibia). * **Option C:** A fracture of the distal end of the radius is most commonly a **Colles’ fracture** (dorsal displacement) or a **Smith’s fracture** (volar displacement). * **Option D:** Pathological fractures in osteomalacia are typically referred to as **Looser’s zones** or Milkman’s fractures (pseudofractures). **High-Yield Clinical Pearls for NEET-PG:** * **Lauge-Hansen Classification:** The most widely used system for ankle fractures based on the foot position and the direction of the deforming force. * **Danis-Weber Classification:** Categorizes ankle fractures based on the level of the fibular fracture relative to the syndesmosis (Type A, B, and C). * **Management:** Stable fractures are treated with a below-knee cast; however, most Potts fractures are unstable and require **Open Reduction and Internal Fixation (ORIF)** to restore the anatomy of the ankle mortise. * **Maisonneuve Fracture:** A high-yield variant involving a proximal fibular fracture associated with a medial malleolar break or deltoid ligament rupture.

Q: What is the best treatment for a fracture and dislocation of the lateral clavicle?

Surgical repair. **Explanation:** Fractures of the lateral (distal) third of the clavicle are classified using the **Neer Classification**. When a fracture is associated with a dislocation or instability (specifically Neer Type II), it indicates that the coracoclavicular (CC) ligaments are detached from the proximal fragment. **1. Why Surgical Repair is Correct:** In lateral clavicle fractures with dislocation, the weight of the arm pulls the distal fragment downward, while the sternocleidomastoid muscle pulls the proximal fragment upward. This significant displacement and the loss of ligamentous stability lead to a **high rate of non-union (up to 30-40%)** if treated conservatively. Therefore, **Surgical Repair** (using techniques like hook plates, tension band wiring, or CC ligament reconstruction) is the treatment of choice to ensure anatomical reduction and bone healing. **2. Why Incorrect Options are Wrong:** * **A & C (Figure of 8 splint / Normal sling):** These are conservative management options. While appropriate for undisplaced mid-shaft fractures (Neer Type I or III), they cannot counteract the strong deforming forces in unstable lateral fractures, leading to malunion or persistent non-union. * **B (Open reduction):** While open reduction is a *step* in the procedure, "Surgical repair" is the more comprehensive term that includes both reduction and the necessary internal fixation/ligamentous stabilization required for this specific injury. **Clinical Pearls for NEET-PG:** * **Neer Type II** is the most common lateral clavicle fracture requiring surgery. * **Most common site of clavicle fracture:** Middle third (80%), usually treated conservatively with a U-slab or triangular sling. * **Allman Classification:** Group I (Mid-shaft), Group II (Lateral), Group III (Medial). * **Complication:** The most common complication of clavicle fractures is **malunion**, but for lateral Type II fractures, it is **non-union**.

Q: A 40-year-old man was admitted with fracture of the shaft of the femur following a road traffic accident. On the 2nd day, he became disoriented, was found to be tachypnoeic, and had conjunctival petechiae. What is the most likely diagnosis?

Fat embolism. ### Explanation The clinical presentation described is a classic triad of **Fat Embolism Syndrome (FES)**, which typically occurs 24–72 hours after a long bone fracture (most commonly the femur). **Why Fat Embolism is the Correct Answer:** Fat embolism occurs when fat globules from the bone marrow enter the systemic circulation following a fracture. The diagnosis is primarily clinical, based on **Gurd’s Criteria**. This patient exhibits the classic triad: 1. **Respiratory Distress:** Tachypnoea and hypoxia. 2. **Neurological Changes:** Disorientation/confusion (due to cerebral microemboli). 3. **Petechial Rash:** Characteristically found in the conjunctiva, axilla, and neck (pathognomonic but present in only 20-50% of cases). **Why Other Options are Incorrect:** * **Pulmonary Embolism (PE):** While it causes tachypnoea, it usually occurs later (1–2 weeks post-injury) due to DVT. It does not present with petechiae. * **Sepsis Syndrome:** Usually presents with fever, hypotension, and a clear source of infection. The 48-hour window and petechiae are more specific to FES. * **Haemothorax:** This would present immediately after trauma with decreased breath sounds and dullness on percussion, not after a 2-day "latent period." **High-Yield Clinical Pearls for NEET-PG:** * **Most common cause:** Fracture of the shaft of the femur. * **Earliest sign:** Hypoxia (PaO2 < 60 mmHg). * **Pathognomonic sign:** Petechial rash. * **Investigation of choice:** Clinical diagnosis; however, "Snowstorm appearance" may be seen on Chest X-ray. * **Treatment:** Primarily supportive (Oxygenation/Ventilation). Early splintage and fixation of the fracture are the best preventive measures.

Q: What is the common site of fracture in the tibia?

Junction of upper two-thirds and lower one-third. The tibia is the most commonly fractured long bone in the body. The **junction of the upper two-thirds and lower one-third** of the shaft is the most frequent site of fracture due to two primary anatomical factors: 1. **Change in Cross-sectional Shape:** The tibial shaft transitions from a robust, triangular cross-section in its upper two-thirds to a weaker, cylindrical (circular) cross-section in the lower one-third. This transition zone creates a natural point of mechanical weakness. 2. **Nutrient Artery Entry:** The nutrient artery enters the posterior surface of the tibia in its upper third and runs downwards. Fractures at the junction of the middle and lower thirds often disrupt this blood supply, leading to a high incidence of delayed union or non-union. **Analysis of Options:** * **Option A & D:** While fractures can occur in the upper and middle thirds (often due to direct high-energy trauma), these areas are wider and have better muscular coverage and blood supply compared to the distal junction. * **Option C:** While the lower one-third is vulnerable, the specific point of maximal weakness is the transition zone where the bone morphology changes (the junction). **Clinical Pearls for NEET-PG:** * **Blood Supply:** The lower third of the tibia is notorious for poor blood supply because it lacks significant muscular attachments (it is mostly subcutaneous). * **Compound Fractures:** Because the anteromedial surface of the tibia is subcutaneous throughout its length, tibial fractures are the most common **open (compound) fractures** in the body. * **March Fracture:** This refers to a stress fracture, typically involving the neck of the 2nd or 3rd metatarsal, not the tibia. * **Runner's High-Yield:** Medial Tibial Stress Syndrome (Shin Splints) typically involves the distal two-thirds of the tibial shaft.

Question 1

What type of Monteggia fracture is commonly associated with nerve injuries?

Accepted Answer

Type II

Answer

Type I

Answer

Type III

Answer

Type IV

Question 2

Which of the following is NOT relevant in the management of compartment syndrome?

Accepted Answer

Exercise

Answer

Fasciotomy

Answer

Splitting of a tight cast

Answer

Reexploration

Question 3

What is commonly referred to as a Potts fracture?

Accepted Answer

Bimalleolar ankle fracture

Answer

Trimalleolar ankle fracture

Answer

Fracture of distal end radius

Answer

Pathological fracture in osteomalacia

Question 4

A Morel-Lavallee lesion is typically associated with which type of fracture?

Accepted Answer

Acetabular fracture

Answer

Femoral neck fracture

Answer

Lumbar spine fracture

Answer

Proximal tibia fracture

Question 5

What is the best treatment for a fracture and dislocation of the lateral clavicle?

Accepted Answer

Surgical repair

Answer

Figure of 8 splint

Answer

Open reduction

Answer

Normal sling

Question 6

The fracture of the tooth-bearing segment of the mandible is classified as which type?

Accepted Answer

Compound

Answer

Simple

Answer

Complex

Answer

Comminuted

Question 7

What is the treatment for a displaced proximal olecranon fracture?

Accepted Answer

Tension band wiring

Answer

Excision and resuturing

Answer

Immobilization of the elbow by cast

Answer

Open reduction and external fixation

Question 8

A 40-year-old man was admitted with fracture of the shaft of the femur following a road traffic accident. On the 2nd day, he became disoriented, was found to be tachypnoeic, and had conjunctival petechiae. What is the most likely diagnosis?

Accepted Answer

Fat embolism

Answer

Pulmonary embolism

Answer

Sepsis syndrome

Answer

Haemothorax

Question 9

What is the first muscle to be involved in Volkmann's ischemic contracture of the forearm?

Accepted Answer

Flexor digitorum profundus

Answer

Flexor digitorum superficialis

Answer

Flexor Carpi Radialis

Answer

Extensor carpi radialis brevis

Question 10

What is the common site of fracture in the tibia?

Accepted Answer

Junction of upper two-thirds and lower one-third

Answer

Upper one-third

Answer

Lower one-third

Answer

Middle one-third

Trauma — MCQs

Trauma — MCQs

On this page

Practice by Chapter

Want unlimited practice?