Anatomy
1 questionsA person is not able to extend his metacarpophalangeal joint. Injury to which of the following nerve result in this?
NEET-PG 2013 - Anatomy NEET-PG Practice Questions and MCQs
Question 941: A person is not able to extend his metacarpophalangeal joint. Injury to which of the following nerve result in this?
- A. Posterior Interosseous nerve injury (Correct Answer)
- B. Radial nerve injury
- C. Ulnar nerve injury
- D. Median nerve injury
Explanation: Posterior Interosseous Nerve (PIN) injury - The Posterior Interosseous Nerve is the deep motor branch of the radial nerve that specifically innervates the extensor muscles of the fingers and thumb - These muscles include: Extensor Digitorum, Extensor Indicis, Extensor Digiti Minimi, Extensor Pollicis Longus and Brevis [1] - PIN injury causes inability to extend the MCP joints and interphalangeal joints of the fingers [1] - Wrist extension is preserved because the Extensor Carpi Radialis Longus (ECRL) and often ECRB are innervated by the radial nerve proper before it gives off the PIN [1] - This results in a characteristic finger drop without wrist drop Radial nerve injury - A high radial nerve injury (proximal, above the elbow) would cause both wrist drop AND finger extension loss - However, radial nerve injury at the spiral groove (most common site) typically spares the PIN or affects it less severely - The question asks specifically about isolated inability to extend MCP joints, which is the hallmark of PIN injury, not general radial nerve injury - Radial nerve proper gives branches to triceps, brachioradialis, and ECRL before dividing into PIN and superficial branch Ulnar nerve injury - The ulnar nerve innervates intrinsic hand muscles (interossei, lumbricals to digits 4-5, hypothenar muscles, adductor pollicis) [1] - Ulnar nerve injury causes claw hand deformity with MCP hyperextension (not loss of extension) and IP joint flexion - This is the opposite of what is described in the question Median nerve injury - The median nerve innervates the thenar muscles, lateral two lumbricals, and forearm flexors [1] - Median nerve injury causes ape hand deformity with loss of thumb opposition and flexion - It does not affect MCP joint extension, which is an extensor function
Orthopaedics
8 questionsWhat is the characteristic feature of Barton's fracture?
Madelung's deformity is characterized by an abnormality in which bone?
Garden spade deformity is seen in ?
Block vertebrae are seen in which condition?
What is a Hangman's fracture?
Most common cause of kyphotic deformity ?
Saturday night palsy is which type of nerve injury?
Which of the following movements is typically restricted in Perthes disease?
NEET-PG 2013 - Orthopaedics NEET-PG Practice Questions and MCQs
Question 941: What is the characteristic feature of Barton's fracture?
- A. Extra-articular fracture of the distal end radius
- B. Intra-articular fracture of the distal end radius without carpal bone subluxation
- C. Intra-articular fracture of the distal end radius with carpal bone subluxation
- D. Intra-articular fracture of the distal end radius with carpal bone subluxation and joint involvement (Correct Answer)
Explanation: ***Intra-articular fracture of the distal end radius with carpal bone subluxation and joint involvement*** - A **Barton's fracture** is defined as an **intra-articular fracture** of the distal radius involving the dorsal or volar rim, accompanied by **subluxation of the carpus**. - The displacement of the **carpal bones** relative to the fractured radius is a hallmark of this injury, necessitating careful reduction for optimal outcome. *Extra-articular fracture of the distal end radius* - An **extra-articular fracture** means the fracture line does not extend into the joint space, which is not characteristic of a Barton's fracture. - Examples of extra-articular distal radius fractures include some types of **Colles' fractures** or **Smith's fractures** without joint involvement. *Intra-articular fracture of the distal end radius without carpal bone subluxation* - While a Barton's fracture is intra-articular, the crucial distinguishing feature is the accompanying **carpal subluxation**. - An **intra-articular fracture** without carpal subluxation would be classified differently, such as a **Chauffeur's fracture** or certain types of **die-punch fractures**. *Intra-articular fracture of the distal end radius with carpal bone subluxation* - This option is partially correct but less complete than the best answer, as it implies joint involvement by definition but doesn't explicitly state it. - The combination of **intra-articular involvement** and **carpal subluxation** explicitly defines a Barton's fracture, whether dorsal or volar.
Question 942: Madelung's deformity is characterized by an abnormality in which bone?
- A. Humerus
- B. Proximal ulna
- C. Distal radius (Correct Answer)
- D. Carpals
Explanation: ***Distal radius*** - **Madelung's deformity** is primarily characterized by a **malformation of the distal radius**, specifically the physis (growth plate). - This leads to abnormal growth, causing the **radius to shorten and bow** dorsally, resulting in a prominent distal ulna. *Humerus* - The **humerus** is the bone of the upper arm, and abnormalities of this bone are not characteristic of Madelung's deformity. - Conditions affecting the humerus typically involve the shoulder or elbow joint, distinct from the wrist pathology seen in Madelung's. *Proximal ulna* - The **proximal ulna** forms part of the elbow joint, and while the ulna can be affected, the primary abnormality in Madelung's is in the radius. - While the ulna may appear prominent, this is secondary to the radial deformity, not a primary issue of the proximal ulna. *Carpals* - The **carpal bones** are located in the wrist, distal to the radius and ulna, and are not the primary site of deformity in Madelung's. - While wrist motion may be affected, the underlying cause is the abnormal growth of the distal radius, which can then impact carpal alignment.
Question 943: Garden spade deformity is seen in ?
- A. Smith's fracture (Correct Answer)
- B. Colle’s fracture
- C. Bennett’s fracture
- D. Barton’s fracture
Explanation: ***Smith's fracture*** - This fracture involves **volar displacement** of the distal radial fragment, causing the characteristic **garden spade deformity** or **reverse Colles' fracture**. - It typically results from a fall onto a **flexed wrist** or a direct blow to the back of the wrist. *Colle’s fracture* - This fracture is characterized by **dorsal displacement** of the distal radial fragment, leading to a **dinner fork deformity**. - It usually occurs from a fall onto an **extended wrist**. *Bennett’s fracture* - This is an **intra-articular fracture** of the base of the **first metacarpal bone**, involving the carpometacarpal joint. - It is often caused by axial loading on a partially flexed thumb. *Barton’s fracture* - This is an **intra-articular fracture** of the distal radius involving either the **dorsal or volar rim**. - It is essentially a **shear fracture** with associated carpal displacement.
Question 944: Block vertebrae are seen in which condition?
- A. Pagets disease
- B. Leukemia
- C. TB
- D. Klippel-Feil syndrome (Correct Answer)
Explanation: ***Klippel-Feil syndrome*** - **Block vertebrae** are a characteristic radiographic finding in **Klippel-Feil syndrome**, resulting from the congenital fusion of two or more cervical vertebrae. - This fusion leads to a **short neck**, **low hairline**, and **restricted neck motion**. *Pagets disease* - **Paget's disease** is a chronic condition of abnormal bone remodeling, leading to enlarged and weakened bones. - While it can cause vertebral body changes, **block vertebrae** resulting from congenital fusion are not a typical feature. *Leukemia* - **Leukemia** involves uncontrolled proliferation of abnormal white blood cells, which can infiltrate bone marrow and cause lytic or blastic lesions in bones. - It does not cause **block vertebrae**, which are a developmental anomaly. *TB* - **Tuberculosis (TB) of the spine (Pott's disease)** is an infectious condition causing vertebral destruction, collapse, and kyphosis. - While TB can lead to vertebral collapse and eventual fusion during healing, the primary pathology is destructive and not the congenital fusion seen as **block vertebrae**.
Question 945: What is a Hangman's fracture?
- A. Fracture dislocation of C2 (Correct Answer)
- B. Fracture dislocation of ankle joint
- C. Fracture of odontoid
- D. Subluxation of C5 over C6
Explanation: ***Fracture dislocation of C2*** - A Hangman's fracture classically refers to a **bilateral fracture of the pars interarticularis of the axis (C2)**, often with an associated anterior subluxation of C2 on C3. - This injury is typically caused by **hyperextension-distraction forces**, such as those experienced in judicial hangings or motor vehicle accidents. *Subluxation of C5 over C6* - While cervical subluxations are serious, a **C5-C6 subluxation** does not specifically describe a Hangman's fracture. - This type of injury involves different vertebral levels and typically results from different mechanisms. *Fracture dislocation of ankle joint* - This option refers to an injury in the **lower limb**, completely unrelated to the cervical spine. - A Hangman's fracture is a specific type of **cervical vertebral fracture**. *Fracture of odontoid* - A fracture of the odontoid process involves the **dens (odontoid process)** of C2. - This is a distinct type of C2 fracture from a Hangman's fracture, which involves the **pars interarticularis**.
Question 946: Most common cause of kyphotic deformity ?
- A. Trauma
- B. Osteoporosis (Correct Answer)
- C. Ankylosing spondylitis
- D. Rickets
Explanation: ***Osteoporosis*** - **Osteoporosis** leads to vertebral compression fractures, particularly in the thoracic spine, which causes a gradual collapse of the vertebral bodies and an increase in the kyphotic curve. - This condition is very common, especially in **postmenopausal women** and the elderly, making it the most frequent cause of kyphotic deformity. *Trauma* - While significant **spinal trauma** can lead to kyphotic deformities, it is generally less common than the gradual kyphosis resulting from osteoporosis. - Traumatic kyphosis usually results from severe injuries leading to **vertebral body collapse** or neurological deficits. *Ankylosing spondylitis* - **Ankylosing spondylitis** can cause severe kyphosis, often referred to as a "bamboo spine," due to chronic inflammation and fusion of the vertebrae. - However, it is a less prevalent condition compared to **osteoporosis-related kyphosis**. *Rickets* - **Rickets**, a childhood bone disorder caused by **vitamin D deficiency**, can lead to bone deformities including kyphosis due to softened bones. - While a cause in children, its prevalence is lower than osteoporosis globally as a cause of kyphosis and it primarily affects a different age group.
Question 947: Saturday night palsy is which type of nerve injury?
- A. Neuropraxia (Correct Answer)
- B. Axonotemesis
- C. Complete section
- D. Neurotmesis
Explanation: ***Neuropraxia*** - This is the mildest form of nerve injury, involving a **temporary conduction block** without axonal disruption, often due to **compression** or mild stretching. - **Saturday night palsy**, caused by prolonged compression of the radial nerve, is a classic example, characterized by rapid and complete recovery, typically within days to weeks. *Axonotemesis* - This involves **axon damage** and Wallerian degeneration distal to the injury, but the **endoneurium and connective tissue sheaths remain intact**. - Recovery is slower and often incomplete, as it requires axonal regeneration through the preserved connective tissue tubes, taking months. *Neurotmesis* - This is the most severe type of nerve injury, involving **complete transection of the nerve fiber**, including the axon, myelin, and all connective tissue sheaths. - Recovery is often poor and requires surgical intervention to attempt re-approximation of the nerve ends. *Complete section* - This term is largely synonymous with **neurotmesis**, indicating a full anatomical disruption of the nerve. - It involves the severance of all nerve components, leading to complete loss of function distal to the injury and the poorest prognosis for spontaneous recovery.
Question 948: Which of the following movements is typically restricted in Perthes disease?
- A. Abduction & internal rotation (Correct Answer)
- B. Abduction & external rotation
- C. Adduction & internal rotation
- D. Adduction & external rotation
Explanation: ***Abduction & internal rotation*** - **Perthes disease** affects the femoral head, leading to pain and stiffness that most commonly restricts **abduction** and **internal rotation** of the hip. - This restriction is an early and consistent clinical finding, often accompanied by a ** Trendelenburg gait** due to gluteal muscle weakness or pain avoidance. *Abduction & external rotation* - While abduction can be restricted, a primary restriction in **external rotation** is less typical in early Perthes disease. - Reduced external rotation is more characteristic of conditions like **slipped capital femoral epiphysis (SCFE)**, especially in older children. *Adduction & internal rotation* - **Adduction** is generally preserved or even increased in Perthes disease as the hip seeks a position of comfort due to pain, making it an unlikely primary restriction. - While internal rotation is restricted, the combination with adduction restriction is not the classical presentation. *Adduction & external rotation* - Neither **adduction** nor **external rotation** are typically the primary hip movements restricted in Perthes disease. - Restriction in adduction is rare, and external rotation is often compensatory or less affected than internal rotation.
Pathology
1 questionsWhat are the common causes of vertebra plana?
NEET-PG 2013 - Pathology NEET-PG Practice Questions and MCQs
Question 941: What are the common causes of vertebra plana?
- A. Eosinophilic granuloma
- B. Metastatic disease
- C. Tuberculosis
- D. All of the options (Correct Answer)
Explanation: ***All of the options*** - **Vertebra plana** refers to the severe flattening of a vertebral body, often caused by a destructive lesion, and all listed options are known causes. [5] - While **eosinophilic granuloma** is a classic cause, **metastatic disease** and **tuberculosis** can also lead to significant vertebral collapse. [3], [5] *Eosinophilic granuloma* - This is a benign condition, a form of **Langerhans cell histiocytosis**, which commonly affects children and can cause vertebra plana. [1] - It results from proliferative lesions of **Langerhans cells** that infiltrate the bone, leading to its destruction and collapse. [1] *Metastatic disease* - **Malignant tumors** often spread to the spine, causing osteolytic lesions that weaken the vertebral body. [4], [5] - The destruction caused by metastatic deposits can lead to **vertebral collapse** and associated pain. [5] *Tuberculosis* - **Tuberculosis of the spine (Pott's disease)** is an infectious inflammatory condition that can severely damage vertebral bodies. [2], [3] - The granulomatous inflammation and caseous necrosis can erode the bone, leading to **vertebral collapse** and kyphosis. [2] **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus, p. 630. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Bones, Joints, and Soft Tissue Tumors, pp. 1197-1198. [3] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Osteoarticular And Connective Tissue Disease, pp. 669-670. [4] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Lung, pp. 724-725. [5] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Osteoarticular And Connective Tissue Disease, pp. 671-672.