Arthrology and Infections — MCQs

Arthrology and Infections Indian Medical PG Practice Questions and MCQs

Question 41: What is the treatment of Garre's osteomyelitis?

A. Incision and drainage
B. Sequestrectomy
C. Saucerization
D. Surgical recontouring (Correct Answer)

Explanation: **Explanation:** **Garre’s Sclerosing Osteomyelitis** is a specific type of chronic non-suppurative osteomyelitis characterized by intense periosteal reaction and reactive bone formation. It typically affects children and young adults, most commonly involving the mandible or the tibia. 1. **Why Surgical Recontouring is Correct:** Unlike pyogenic osteomyelitis, Garre’s is characterized by **bone thickening and expansion** rather than pus formation or necrosis. The primary clinical concern is often the cosmetic deformity and persistent dull aching pain caused by the thickened cortex. **Surgical recontouring** (shaving down the excess bone) is the definitive treatment to restore normal anatomy and relieve pressure, provided the underlying source of infection (like a carious tooth) has been addressed. 2. **Why Other Options are Incorrect:** * **Incision and Drainage:** This is indicated for acute abscesses. Garre’s is a non-suppurative condition; there is no pus to drain. * **Sequestrectomy:** A sequestrum (dead bone) is a hallmark of chronic pyogenic osteomyelitis. In Garre’s, there is **no sequestrum or involucrum** formation. * **Saucerization:** This involves creating a shallow groove to allow a wound to heal from the bottom up in chronic osteomyelitis with cavities. Garre’s presents with solid bony enlargement, not cavities. **NEET-PG High-Yield Pearls:** * **Radiological Appearance:** Characterized by "onion-skin" periosteal reaction (concentric layers of new bone). * **Key Feature:** There is a total absence of suppuration, sequestration, or sinus tracts. * **Common Site:** The mandible is the most frequent site, often secondary to a low-grade odontogenic infection. * **Management:** First-line treatment is conservative (antibiotics and removal of the primary focus). Surgery (recontouring) is reserved for persistent deformity or pain.

Question 42: Osteomyelitis of the jaw can be cured by?

A. Resection
B. Physiotherapy
C. Sequestrectomy with antibiotic treatment (Correct Answer)
D. Drainage

Explanation: **Explanation:** The management of chronic osteomyelitis, particularly in the jaw (mandible), is centered on the removal of necrotic tissue and the eradication of infection. **Why Option C is Correct:** The hallmark of chronic osteomyelitis is the formation of a **sequestrum**—a piece of dead bone that has become detached from the healthy bone. Because the sequestrum is avascular, systemic antibiotics cannot reach the bacteria residing within it. Therefore, **sequestrectomy** (surgical removal of the dead bone) is mandatory. This must be combined with long-term, culture-sensitive **antibiotic treatment** to eliminate the residual infection in the surrounding vascularized bone and soft tissue. **Analysis of Incorrect Options:** * **A. Resection:** This involves removing a segment of the bone. While used in aggressive cases or malignancies, it is overly radical for standard osteomyelitis and leads to significant functional and aesthetic deformity. * **B. Physiotherapy:** This is a supportive treatment for joint mobility but has no role in treating an active bacterial infection of the bone. * **D. Drainage:** Simple incision and drainage (I&D) are effective for acute abscesses in soft tissue, but they fail to address the underlying necrotic bone (sequestrum) which acts as a persistent nidus for infection. **High-Yield Clinical Pearls for NEET-PG:** * **Involucrum:** The layer of new periosteal bone that forms around the sequestrum. * **Cloaca:** The opening in the involucrum through which pus and debris escape. * **Most Common Organism:** *Staphylococcus aureus* remains the most common cause of osteomyelitis overall. * **Imaging:** MRI is the most sensitive modality for early diagnosis; however, a CT scan is superior for identifying a sequestrum.

Question 43: Which of the following is NOT a clinical feature of Chronic Osteomyelitis?

A. Excruciating pain and tenderness (Correct Answer)
B. Non-healing bony and overlying soft tissue wounds with indurated soft tissue
C. Wooden character of bone
D. Draining sinuses

Explanation: **Explanation:** The hallmark of **Chronic Osteomyelitis** is a low-grade, persistent infection characterized by the presence of necrotic bone (**sequestrum**) and a reactive sheath of new bone (**involucrum**). **Why Option A is the Correct Answer:** Excruciating pain and high-grade tenderness are classic features of **Acute Osteomyelitis**, where there is rapid intramedullary pressure buildup and systemic toxicity. In contrast, Chronic Osteomyelitis is typically **painless** or presents with only a dull ache. If a patient with chronic osteomyelitis suddenly develops excruciating pain, it usually indicates a pathological fracture or an acute flare-up (acute-on-chronic). **Analysis of Incorrect Options:** * **Option B:** Chronic infection leads to persistent inflammation, resulting in **non-healing wounds** and **indurated (thickened/hardened) soft tissue** due to long-standing fibrosis and scarring. * **Option C:** The formation of a thick, irregular involucrum around the infected site gives the bone a thickened, rough, and **"wooden" character** on palpation. * **Option D:** **Draining sinuses** are a pathognomonic feature. These tracts allow the discharge of pus and occasionally small pieces of sequestra from the infected bone to the skin surface. **High-Yield Clinical Pearls for NEET-PG:** * **Gold Standard Investigation:** Bone Biopsy and Culture. * **Radiological Sign:** Sequestrum (dead bone, appears radio-opaque) and Involucrum (new bone, appears radio-lucent/surrounding). * **Brodie’s Abscess:** A form of subacute osteomyelitis characterized by a radiolucent nidus surrounded by sclerosis. * **Complication:** Long-standing discharging sinuses in chronic osteomyelitis can lead to **Marjolin’s Ulcer** (Squamous Cell Carcinoma).

Question 44: In rheumatoid arthritis, which part of the spinal column is most commonly involved?

A. Cervical vertebrae (Correct Answer)
B. Dorsal vertebrae
C. Lumbar vertebrae
D. Sacral vertebrae

Explanation: **Explanation:** **1. Why Cervical Vertebrae is correct:** Rheumatoid Arthritis (RA) primarily targets **synovial joints**. The cervical spine is the only part of the spinal column that contains true synovial joints, specifically the **atlanto-axial joint** (C1-C2) and the **facet joints** (zygapophyseal joints). The most characteristic involvement is **Atlanto-axial subluxation**, caused by synovial inflammation and erosion of the transverse ligament of the atlas, which normally stabilizes the odontoid process. This makes the cervical spine the most common (and most clinically significant) site of spinal RA. **2. Why other options are incorrect:** * **Dorsal (Thoracic) and Lumbar vertebrae:** These regions are rarely involved in RA because they lack the high density of synovial joints found in the cervical region. While facet joints exist here, they are less prone to the aggressive pannus formation seen in the neck. Involvement of the lower spine is more characteristic of **Seronegative Spondyloarthropathies** (like Ankylosing Spondylitis). * **Sacral vertebrae:** The sacrum consists of fused vertebrae. The sacroiliac joint is typically spared in RA, which helps differentiate it from Ankylosing Spondylitis, where sacroiliitis is a hallmark feature. **3. NEET-PG High-Yield Pearls:** * **Most common cervical level:** C1-C2 (Atlanto-axial joint). * **Radiographic finding:** Increased **Atlantodental Interval (ADI)**; >3mm in adults is considered abnormal. * **Subaxial Subluxation:** "Stepladder deformity" (multiple levels of subluxation) is a classic radiological description of RA in the lower cervical spine. * **Clinical Warning:** Patients with RA requiring surgery must have cervical X-rays to rule out instability before intubation to prevent spinal cord injury.

Question 45: What is the most common type of spinal tuberculosis?

A. Anterior
B. Posterior
C. Central
D. Paradiscal (Correct Answer)

Explanation: **Explanation:** Spinal tuberculosis (Pott’s disease) is the most common form of skeletal tuberculosis. The classification of the disease is based on the initial site of vertebral involvement. **1. Why Paradiscal is the Correct Answer:** The **Paradiscal** type is the most common variety (seen in ~95% of cases). The infection typically begins in the subchondral bone of the vertebral body adjacent to the intervertebral disc. Because the arterial supply to the vertebrae (via the segmental arteries) bifurcates to supply the adjacent margins of two vertebrae, the infection easily spreads across the disc space to involve the neighboring vertebra. This leads to the characteristic **narrowing of the disc space** seen on X-ray. **2. Why Other Options are Incorrect:** * **Central:** The infection starts in the center of the vertebral body. It often leads to early collapse and "vertebra plana," but it is less common than the paradiscal type. * **Anterior:** The infection involves the anterior surface of the vertebral body and spreads under the anterior longitudinal ligament. It is common in children but not the overall most frequent type. * **Posterior:** This involves the posterior elements (lamina, spines, pedicles). It is rare and clinically significant because it often leads to early neurological deficits due to spinal cord compression. **Clinical Pearls for NEET-PG:** * **Most common site:** Lower Thoracic and Upper Lumbar spine (T12-L1). * **Earliest X-ray sign:** Rarefaction (osteopenia) of the paradiscal margins and narrowing of the disc space. * **Cold Abscess:** A hallmark of Pott’s disease; it is "cold" because it lacks the typical signs of acute inflammation (heat, redness). * **Deformity:** The destruction of the anterior part of the vertebrae leads to **Kyphosis** (Gibbus deformity).

Question 46: What is the most common complication of a Colles fracture?

A. Malunion
B. Avascular necrosis
C. Finger stiffness (Correct Answer)
D. Rupture of EPL tendon

Explanation: **Explanation:** The most common complication of a Colles fracture is **finger stiffness**. This occurs primarily due to prolonged immobilization in a plaster cast and the patient's failure to perform active finger exercises during the healing period. The resulting edema and lack of joint mobilization lead to adhesions in the small joints of the hand and the flexor tendons. **Analysis of Options:** * **Finger Stiffness (Correct):** It is the most frequent complication. It is often preventable with early physiotherapy and "active mobilization" of the fingers while the wrist is in a cast. * **Malunion (A):** This is the most common **bony** complication, leading to the characteristic "Dinner Fork Deformity." While frequent, it is statistically less common than soft tissue stiffness. * **Avascular Necrosis (B):** This is rare in Colles fractures because the distal radius has a rich blood supply. AVN is more characteristic of Scaphoid fractures or femoral neck fractures. * **Rupture of EPL Tendon (D):** This is a classic late complication caused by attrition of the Extensor Pollicis Longus tendon against the irregular bony surface at Lister’s tubercle. While high-yield for exams, it is relatively rare (occurring in ~1-5% of cases). **NEET-PG High-Yield Pearls:** * **Sudeck’s Atrophy (CRPS Type 1):** A serious complication characterized by pain, swelling, and vasomotor instability. * **Median Nerve Palsy:** The most common nerve involved (Carpal Tunnel Syndrome). * **Dinner Fork Deformity:** Caused by dorsal displacement, dorsal tilt, and lateral tilt of the distal fragment. * **Treatment of Choice:** Closed reduction and cast immobilization (Colles cast) in a position of slight flexion and ulnar deviation.

Question 47: Which of the following is not a type of chronic osteomyelitis?

A. Garre's osteomyelitis
B. Chronic suppurative osteomyelitis
C. Condensing osteitis
D. None of the above (Correct Answer)

Explanation: **Explanation:** Chronic osteomyelitis is a persistent infection of the bone characterized by the presence of necrotic bone (**sequestrum**), new bone formation (**involucrum**), and often, discharging sinuses. It can manifest in several clinical forms depending on the virulence of the organism and the host's immune response. **Why "None of the above" is correct:** All the options listed (A, B, and C) are recognized subtypes of chronic osteomyelitis. Therefore, none of them can be excluded from the category. * **Garre’s Sclerosing Osteomyelitis:** A specific type of chronic non-suppurative osteomyelitis characterized by peripheral reactive bone formation and cortical thickening. It typically affects the mandible or tibia in children and young adults, often triggered by a low-grade irritation or infection. * **Chronic Suppurative Osteomyelitis:** The most common form, usually following inadequately treated acute osteomyelitis. It involves pus formation, sequestrum, and discharging sinuses. * **Condensing Osteitis:** A variant of focal sclerosing osteomyelitis usually seen at the apex of a tooth with a long-standing pulpitis. It represents a localized bony reaction to a low-grade inflammatory stimulus. **High-Yield Clinical Pearls for NEET-PG:** * **Brodie’s Abscess:** A form of subacute or chronic osteomyelitis appearing as a radiolucent lesion surrounded by sclerosis, most commonly in the **metaphysis of the tibia**. * **Pathognomonic Sign:** The presence of a **sequestrum** (dead bone) is the hallmark of chronic osteomyelitis on X-ray. * **Marjolin’s Ulcer:** A rare but serious complication where squamous cell carcinoma develops in the chronic discharging sinus tract of osteomyelitis. * **Gold Standard Investigation:** While X-rays show involucrum and sequestrum, **MRI** is the most sensitive for early detection, and **Bone Biopsy/Culture** is the gold standard for definitive diagnosis.

Question 48: Prenatal determination of osteogenesis imperfecta is done by?

A. Acid phosphatase
B. Alkaline phosphatase
C. Abnormal Pro- alpha chain (Correct Answer)
D. Neutral phosphatase

Explanation: **Explanation:** **Osteogenesis Imperfecta (OI)**, also known as "Brittle Bone Disease," is a genetic disorder primarily caused by mutations in the **COL1A1** and **COL1A2** genes. These genes are responsible for the synthesis of **Type 1 Collagen**, the most abundant protein in bone matrix. 1. **Why "Abnormal Pro-alpha chain" is correct:** Type 1 collagen is composed of a triple helix formed by two pro-alpha 1 chains and one pro-alpha 2 chain. In OI, mutations lead to either a quantitative deficiency or a qualitative defect (structural abnormality) in these **pro-alpha chains**. Prenatal diagnosis is achieved by analyzing collagen synthesized by cultured **chorionic villus cells** or amniocytes. Biochemical analysis (electrophoresis) detects the presence of these abnormal pro-alpha chains, confirming the diagnosis before birth. 2. **Why other options are incorrect:** * **Alkaline Phosphatase (ALP):** While ALP is a marker of osteoblastic activity and is often elevated in bone remodeling disorders (like Paget’s disease or Rickets), it is not a specific or reliable prenatal marker for OI. * **Acid Phosphatase:** This is a marker of osteoclastic activity (bone resorption) and is not used for the prenatal diagnosis of collagen defects. * **Neutral Phosphatase:** This has no clinical relevance in the diagnosis of metabolic or genetic bone diseases. **High-Yield Clinical Pearls for NEET-PG:** * **Inheritance:** Most common types (Type I and IV) are Autosomal Dominant. * **Clinical Triad:** Fragile bones (multiple fractures), **Blue Sclera** (due to thinning of collagen allowing uveal pigment to show), and **Early-onset Hearing loss** (Otosclerosis). * **Radiology:** Look for "Zebra line" sign (post-bisphosphonate treatment) and "Wormian bones" in the skull. * **Treatment:** Bisphosphonates (e.g., Pamidronate) are the mainstay to increase bone mineral density and reduce fractures.

Question 49: Progressive stiffening of a joint is seen in which of the following conditions?

A. Pericarditis of the shoulder (Correct Answer)
B. Osteochondritis
C. Gout
D. Ankylosis

Explanation: **Explanation:** The hallmark of **Periarthritis of the shoulder** (also known as Adhesive Capsulitis or Frozen Shoulder) is the **progressive, painful stiffening** of the glenohumeral joint. This condition involves chronic inflammation, fibrosis, and thickening of the joint capsule, leading to a gradual loss of both active and passive range of motion (especially external rotation and abduction). It typically progresses through three stages: Freezing (painful), Frozen (stiffening), and Thawing (recovery). **Analysis of Options:** * **Osteochondritis (B):** This refers to joint inflammation involving the bone and cartilage (e.g., Osteochondritis Dissecans). While it causes pain and mechanical symptoms like locking or clicking, it does not typically present with the global, progressive stiffening seen in periarthritis. * **Gout (C):** Gout is a metabolic arthropathy characterized by **acute, episodic attacks** of severe pain, redness, and swelling. Between attacks, the joint usually returns to normal; chronic stiffness only occurs in advanced, untreated tophaceous gout. * **Ankylosis (D):** Ankylosis refers to the **end-stage** of joint destruction where the joint is already fused (either fibrous or bony). It represents a state of permanent immobility rather than a "progressive stiffening" process. **NEET-PG High-Yield Pearls:** * **Adhesive Capsulitis** is most commonly associated with **Diabetes Mellitus** (most common), thyroid disorders, and post-thoracic surgery. * The first movement to be lost and the last to be recovered is **External Rotation**. * **X-ray findings** in Periarthritis are typically **normal**, which helps differentiate it from osteoarthritis or tuberculosis of the shoulder. * Management usually involves NSAIDs, physical therapy, and intra-articular steroid injections.

Question 50: All dead or devitalized bone must be identified by the preoperative injection of a vital stain that stains all living tissue green, leaving dead material unstained. Which of the following conditions is characterized by dead bone material?

A. Acute osteomyelitis with sequestrum
B. Subacute haematogenous osteomyelitis with sequestrum
C. Chronic osteomyelitis with cavity
D. Chronic osteomyelitis with sequestrum (Correct Answer)

Explanation: ### Explanation **1. Why the Correct Answer is Right:** The core concept here is the identification of a **sequestrum**, which is defined as a piece of dead bone that has become separated during the process of necrosis from the surrounding living bone. In **Chronic Osteomyelitis**, the hallmark pathological feature is the presence of infected, devitalized bone (sequestrum) encased in a layer of new living bone (involucrum). The procedure described is **Sequestrectomy**. To ensure complete removal of all necrotic material, a vital dye like **Disulphine Blue** is injected preoperatively. This dye stains living, vascularized tissue green/blue but leaves the avascular, dead sequestrum unstained, acting as a visual guide for the surgeon. **2. Why the Other Options are Incorrect:** * **A & B (Acute/Subacute Osteomyelitis):** While a sequestrum *can* begin to form in acute stages, it is not the defining clinical feature. These stages are primarily characterized by inflammatory exudate, subperiosteal abscesses, or Brodie’s abscess (in subacute). Surgical sequestrectomy using vital stains is reserved for the established chronic stage. * **C (Chronic Osteomyelitis with Cavity):** A cavity alone (Brodie's abscess) contains pus or granulation tissue but does not necessarily contain a sequestrum (dead bone). The question specifically asks for the condition characterized by "dead bone material." **3. NEET-PG High-Yield Pearls:** * **Sequestrum:** Dead bone; appears **radiodense** (whiter) on X-ray because it lacks blood supply and cannot undergo resorption or osteoporosis. * **Involucrum:** A sheath of new, living bone formed around the sequestrum. * **Cloaca:** An opening in the involucrum through which pus and small sequestra escape. * **Vital Stain:** Disulphine Blue is the classic dye used; the "Sandwich Technique" or "Papineau Technique" may be used for managing the resulting bone defect. * **Gold Standard Investigation:** MRI is the most sensitive for early detection, but CT is best for identifying a sequestrum.

Practice by Chapter

Septic Arthritis

Practice Questions

Osteomyelitis

Practice Questions

Tuberculosis of Bones and Joints

Practice Questions

Fungal and Parasitic Infections

Practice Questions

Diabetic Foot Infections

Practice Questions

Prosthetic Joint Infections

Practice Questions

Reactive Arthritis

Practice Questions

Management of Joint Infections

Practice Questions

Prevention of Orthopaedic Infections

Practice Questions

Biofilms in Orthopaedic Infections

Practice Questions

Antibiotic Prophylaxis

Practice Questions

Implant-Related Infections

Practice Questions

Want unlimited practice?

Get full access to all questions, explanations, and performance tracking.

Start For Free