NEET-PG 2015 — Orthopaedics
32 Previous Year Questions with Answers & Explanations
Blount's disease is associated with all of the following, except:
What is the characteristic upper limb deformity seen in Erb's palsy?
Which ligament is most commonly damaged in knee injuries?
Flexor Digitorum Profundus tendon avulsion injury leads to -
Aeroplane splint is used in ?
Thomas test is used for testing?
A child presented to an orthopaedic clinic with a limp. The surgeon suspected him to have a fixed flexion deformity of the hip. Which test should the surgeon perform to confirm his finding?
The A1 pulley involved in trigger finger is located at the level of which joint?
The K nail can be used for all of the following types of fractures except -
All of the following are true regarding the application of POP Cast except -
NEET-PG 2015 - Orthopaedics NEET-PG Practice Questions and MCQs
Question 1: Blount's disease is associated with all of the following, except:
- A. External tibial torsion (can occur in some cases)
- B. Genu varum (tibia vara)
- C. Genu recurvatum (hyperextension of the knee) (Correct Answer)
- D. Internal tibial torsion (common in Blount's disease)
Explanation: ***Genu recurvatum (hyperextension of the knee)*** - Blount's disease is primarily characterized by **genu varum** (bowing of the legs) due to abnormal growth of the proximal tibia. - **Genu recurvatum** is not a typical feature or associated deformity of Blount's disease. *Genu varum (tibia vara)* - This is the **hallmark deformity** of Blount's disease, involving an inward bowing of the leg predominantly at the knee. - It results from a growth disturbance in the **medial portion of the proximal tibial physis**. *External tibial torsion (can occur in some cases)* - While less common than internal torsion, **external tibial torsion** can sometimes be a secondary or associated deformitry in complex cases of Blount's disease, especially with progressive bowing. - It involves an outward twisting of the tibia relative to the femur. *Internal tibial torsion (common in Blount's disease)* - **Internal tibial torsion** is a frequently observed deformity in patients with Blount's disease. - It results in an inward rotation of the lower leg, contributing to the overall malalignment alongside the genu varum.
Question 2: What is the characteristic upper limb deformity seen in Erb's palsy?
- A. Adduction and lateral rotation of arm
- B. Adduction and medial rotation of arm (Correct Answer)
- C. Abduction and lateral rotation of arm
- D. Abduction and medial rotation of arm
Explanation: ***Adduction and medial rotation of arm*** - Erb's palsy, resulting from injury to the **upper brachial plexus** (C5-C6 nerve roots), primarily affects the **deltoid**, **supraspinatus**, **infraspinatus**, and **biceps** muscles. - The unopposed action of unaffected muscles, such as the **pectoris major** and **latissimus dorsi**, leads to the characteristic **waiter's tip position**, involving **adduction** and **medial rotation** of the arm. *Adduction and lateral rotation of arm* - This position would imply weakness of the **pectoralis major** and **latissimus dorsi** and stronger activity of the **infraspinatus** and **teres minor**, which is contrary to the muscle deficits in Erb's palsy. - **Lateral rotation** of the arm is typically impaired in Erb's palsy due to weakness of the **infraspinatus** and **teres minor**. *Abduction and lateral rotation of arm* - **Abduction** is severely impacted in Erb's palsy due to paralysis of the **deltoid** and **supraspinatus**. - This position would suggest intact function of muscles that are explicitly weakened or paralyzed in Erb's palsy. *Abduction and medial rotation of arm* - While **medial rotation** can be a component of the deformity, **abduction** is a movement that is significantly impaired in Erb's palsy, making this option incorrect. - The inability to abduct the arm is a hallmark of the condition due to weakness of the **deltoid** and **supraspinatus**.
Question 3: Which ligament is most commonly damaged in knee injuries?
- A. PCL
- B. LCL
- C. MCL
- D. ACL (Correct Answer)
Explanation: ***ACL*** - The **anterior cruciate ligament (ACL)** is highly susceptible to injury, especially during sports involving sudden stops, changes in direction, jumping, and awkward landings. - Its role in stabilizing the knee against **anterior tibial translation** and rotational forces makes it vulnerable to tears. *PCL* - The **posterior cruciate ligament (PCL)** is much stronger than the ACL and less frequently injured, typically requiring a direct blow to the flexed knee (e.g., dashboard injury). - It prevents **posterior tibial translation** relative to the femur. *MCL* - The **medial collateral ligament (MCL)** is commonly injured, often due to a direct blow to the outside of the knee causing a **valgus stress**. - While frequently damaged, it is often injured in conjunction with the ACL but the ACL is more frequently injured in isolation. *LCL* - The **lateral collateral ligament (LCL)** is the least commonly injured of the four major knee ligaments. - It usually results from a direct blow to the inside of the knee causing **varus stress**.
Question 4: Flexor Digitorum Profundus tendon avulsion injury leads to -
- A. Jersey Finger (Correct Answer)
- B. Extensor tendon injury
- C. Ulnar collateral ligament injury
- D. Central slip injury
Explanation: ***Jersey Finger*** - **Jersey finger** is a common name for an avulsion injury of the **flexor digitorum profundus (FDP) tendon** from its insertion on the distal phalanx. - This injury typically occurs when the finger is forcibly extended while the FDP tendon is contracting, often seen in sports where a player grabs an opponent's jersey. *Extensor tendon injury* - An **extensor tendon injury** involves the tendons on the dorsal side of the hand, responsible for extending the fingers. - This is distinct from a **flexor tendon injury**, which involves tendons on the palmar side. *Ulnar collateral ligament injury* - An **ulnar collateral ligament (UCL) injury** most commonly affects the thumb's metacarpophalangeal (MCP) joint, often called **"skier's thumb"**. - This injury involves damage to the ligament supporting the joint, not an avulsion of a flexor tendon. *Central slip injury* - A **central slip injury** affects the middle slip of the extensor digitorum communis tendon over the proximal interphalangeal (PIP) joint. - Untreated, it can lead to a **Boutonnière deformity**, which is characterized by PIP joint flexion and distal interphalangeal (DIP) joint hyperextension.
Question 5: Aeroplane splint is used in ?
- A. Brachial plexus injury (Correct Answer)
- B. Ulnar nerve injury
- C. Radial nerve injury
- D. Scoliosis
Explanation: ***Brachial plexus injury*** - The **aeroplane splint** is specifically designed to support the arm in **abduction** and **external rotation** at the shoulder, with the elbow flexed. - This position helps to relieve tension on the injured **brachial plexus** nerves and prevents contractures, particularly after an **upper brachial plexus injury** (e.g., Erb's palsy). *Radial nerve injury* - Radial nerve injuries typically present with **wrist drop** and difficulty with finger extension. - Splints for radial nerve injury, such as a **dynamic wrist extension splint**, focus on supporting wrist and finger extension, not shoulder abduction. *Ulnar nerve injury* - Ulnar nerve injuries lead to a **claw hand deformity** and sensory loss in the pinky and half of the ring finger. - Splints for ulnar nerve injury aim to prevent hyperextension of the metacarpophalangeal joints and support the interphalangeal joints, often involving static or dynamic splints for the hand. *Scoliosis* - Scoliosis is a **lateral curvature of the spine**, usually treated with bracing (e.g., Boston brace or Milwaukee brace) or surgery. - An aeroplane splint has no role in the management or treatment of scoliosis.
Question 6: Thomas test is used for testing?
- A. Knee flexion
- B. Hip abduction
- C. Hip rotation
- D. Hip flexor tightness (Correct Answer)
Explanation: ***Hip flexor tightness*** - The **Thomas test** is a diagnostic maneuver used specifically to assess for the presence of **flexion contractures** within the hip joint. - It helps identify tightness in muscles such as the **iliopsoas**, rectus femoris, and tensor fasciae latae. *Knee flexion* - While hip flexor tightness can indirectly affect knee position, the Thomas test does not primarily measure the range of motion of **knee flexion** itself. - **Other tests**, such as goniometric measurements of the knee joint, are used to assess knee flexion directly. *Hip abduction* - The Thomas test is not designed to evaluate **hip abduction** range of motion. - Hip abduction is tested through maneuvers that move the leg away from the midline of the body, often with the patient in a side-lying or supine position, assessing muscles like the **gluteus medius** and minimus. *Hip rotation* - The Thomas test does not assess **hip rotation** (internal or external). - Hip rotation is typically evaluated with the hip and knee flexed to 90 degrees, assessing the rotational range of the **femoral head within the acetabulum**.
Question 7: A child presented to an orthopaedic clinic with a limp. The surgeon suspected him to have a fixed flexion deformity of the hip. Which test should the surgeon perform to confirm his finding?
- A. Thomas test (Correct Answer)
- B. Trendelenburgs test
- C. Telescoping test
- D. Nelaton's test
Explanation: ***Thomas test*** - The **Thomas test** is specifically designed to detect a **fixed flexion deformity of the hip**, where the hip cannot fully extend. - During the test, the patient's hip is flexed to flatten the lumbar spine, and if the contralateral leg then rises off the table, it indicates a fixed flexion deformity. *Trendelenburg's test* - The **Trendelenburg's test** assesses the strength and function of the **hip abductor muscles**, primarily the gluteus medius. - A positive result indicates weakness of the abductors on the standing leg, causing the pelvis to drop on the unsupported side, which is unrelated to fixed flexion deformity. *Nelaton's test* - **Nelaton's test** is used to determine the relative position of the **greater trochanter** in relation to the **ischial tuberosity** and **anterior superior iliac spine (ASIS)**, primarily in cases of hip dislocation or fracture. - It would not specifically identify a fixed flexion deformity of the hip joint itself. *Telescoping test* - The **telescoping test** is used to evaluate for hip instability, particularly in infants with **developmental dysplasia of the hip (DDH)**. - It involves applying axial pressure to the femur while moving the hip, assessing for abnormal movement of the femoral head within the acetabulum, and does not directly detect fixed flexion deformity.
Question 8: The A1 pulley involved in trigger finger is located at the level of which joint?
- A. Proximal Interphalngeal joint
- B. Metacarpophalangeal joint (Correct Answer)
- C. Carpometacarpal joint
- D. Distal Interphalangeal joint
Explanation: ***Metacarpophalangeal joint*** - The **A1 pulley** is located at the base of the finger, overlying the **metacarpophalangeal (MCP) joint**. - Its pathological thickening or narrowing can impede the smooth gliding of **flexor tendons**, causing **trigger finger**. *Proximal Interphalangeal joint* - The **A2** and **A3 pulleys** are located at the level of the **proximal phalanx** and **proximal interphalangeal (PIP) joint**, respectively. - While essential for tendon function, they are not primarily involved in typical **trigger finger**. *Distal Interphalangeal joint* - The **A4** and **A5 pulleys** are located at the level of the **middle phalanx** and **distal interphalangeal (DIP) joint**, respectively. - Pathologies at these pulleys are less common in trigger finger and typically affect the **distal tendon glide**. *Carpometacarpal joint* - The **carpometacarpal (CMC) joints** are located at the base of the hand, between the carpal bones and metacarpals. - There are no A pulleys associated with the CMC joints, and they are not directly involved in the mechanism of **trigger finger**.
Question 9: The K nail can be used for all of the following types of fractures except -
- A. Isthmic femur shaft fractures
- B. Intertrochanteric fractures (Correct Answer)
- C. Low subtrochanteric fractures
- D. Distal femur shaft fractures
Explanation: ***Intertrochanteric fractures*** - The K nail (specifically, the Kuntscher nail) is a **straight intramedullary nail** primarily designed for diaphyseal fractures. - It is **not suitable for intertrochanteric fractures** as these are metaphyseal and involve the proximal femur, requiring implants that offer greater stability in this region, such as cephalomedullary nails or plates. *Isthmic femur shaft fractures* - The **Kuntscher nail** was originally developed for and is well-suited for **isthmic femur shaft fractures** due to the narrow canal providing good cortical fixation. - Its design as a straight, broad nail fits snugly in the isthmus, providing excellent stability. *Low subtrochanteric fractures* - While more challenging, **K nails can be used for low subtrochanteric fractures**, especially if the fracture extends into the diaphyseal region. - However, newer implants like **cephalomedullary nails** are often preferred due to better biomechanical stability in this region. *Distal femur shaft fractures* - **K nails can be employed for distal femoral shaft fractures** if the fracture pattern allows for adequate fixation distal to the isthmus without compromising knee joint function. - The nail must be long enough to achieve stability, and the lack of proper locking mechanisms in traditional K nails may be a limiting factor compared to locked intramedullary nails.
Question 10: All of the following are true regarding the application of POP Cast except -
- A. It can be applied in presence of extreme swelling
- B. Gangrene is known complication of a tight plaster cast
- C. Putting the Plaster roll in warm water hastens setting time
- D. It is anhydrous Calcium phosphate (Correct Answer)
Explanation: ***It is anhydrous Calcium phosphate*** - **Plaster of Paris (POP)** is chemically **calcium sulfate hemihydrate** (CaSO₄·½H₂O), not anhydrous calcium phosphate. - Adding water to calcium sulfate hemihydrate causes an exothermic reaction, forming **calcium sulfate dihydrate**, which is the hardened cast. *Putting the Plaster roll in warm water hastens setting time* - **Warm water** increases the rate of the chemical reaction that causes POP to set, thus **hastening the setting time**. - While it speeds up setting, excessively hot water can lead to a cast that sets too quickly or becomes brittle. *It can be applied in presence of extreme swelling* - Applying a non-flexible POP cast in the presence of **extreme swelling** is contraindicated because swelling will rapidly resolve, making the cast loose and ineffective. - Furthermore, if swelling increases unexpectedly under a tight cast, it can lead to dangerous **compartment syndrome**. *Gangrene is known complication of a tight plaster cast* - A **tight plaster cast** can compromise blood supply to the limb by compressing arteries and veins, potentially leading to **ischemia**. - Prolonged ischemia due to a tight cast can cause **tissue necrosis** and ultimately **gangrene** if not identified and treated promptly.