FREEMEDSITE MRCS ACADEMY • ARTICLE 16 • PAPER 1 APPLIED SURGICAL PATHOLOGY

Surgical Pathology, Inflammation and Wound Healing Made Easy for MRCS Part A

Learn the pathology behind surgical wounds, inflammation, collagen, healing by intention, infection, dehiscence and scar complications, then practise 40 original five-option clinical SBAs.

12 teaching modules52 saved revision topics40 fully explained SBAs3 original diagrams

FreeMedSite • 16 October 2026 • Independently written educational practice, not official MRCS questions

How to study this article

For each topic, learn the mechanism first, then the clinical consequence. Use the 52-topic checklist to track progress and complete the 40-question MRCS-style practice test. The quiz includes full explanations of all five options, high-yield exam pearls, examiner traps and answered viva follow-ups.

Recall-informed, not recall-reproduced: MRCS recall files uploaded to this project were consulted for recurring subject areas; original stems and recalled answers were not copied as a purported verified examination key. Clinical content is referenced to recognised resources below.

Safety note: These are educational discussions of pathophysiology. Real wound infections, vascular compromise or abdominal dehiscence need individual clinical assessment and up-to-date protocols.

On this page

Core pathology: adaptation, injury and repairAcute inflammation: vascular events and leukocyte recruitmentChronic inflammation, granulomas and giant cellsHaemostasis and early wound signallingThe four overlapping phases of wound healingFibroblasts, collagen and tensile strengthPrimary, secondary and delayed primary intentionFactors that delay healing and how to optimise themSurgical site infection and wound classesDehiscence, evisceration, seroma and haematomaHypertrophic scars, keloids and contracturesHigh-yield pathology patterns and examiner traps52-topic revision checklist40 five-option SBAsFAQsReferences and next lessons

1. Core pathology: adaptation, injury and repair

Cellular adaptation includes hypertrophy, hyperplasia, atrophy and metaplasia. Reversible injury can cause cell swelling and fatty change; severe irreversible injury culminates in cell death. Regeneration restores normal tissue when proliferative cells and the extracellular scaffold remain intact; fibrosis replaces destroyed tissue with collagen-rich scar. Labile cells (skin, gut epithelium, marrow) continually divide, whereas cardiac muscle has very limited regeneration.

Clinical application

After an uncomplicated superficial mucosal injury, epithelial regeneration may restore the barrier. After transmural infarction or substantial scaffold loss, fibrosis rather than full structural regeneration predominates.

MRCS exam pearl

Hypertrophy increases cell size; hyperplasia increases cell number. Fibrosis is not identical to regeneration.

2. Acute inflammation: vascular events and leukocyte recruitment

An acute inflammatory stimulus causes arteriolar dilation and increased microvascular permeability; exudate is protein-rich, unlike a low-protein transudate caused mainly by pressure imbalance. Neutrophils commonly dominate early bacterial inflammation. Leukocytes undergo rolling (selectins), firm adhesion (integrins), diapedesis and chemotaxis. Histamine promotes early permeability; prostaglandins contribute to pain and fever.

Clinical application

A warm, red, swollen postoperative wound is not automatically infected: sterile postoperative inflammation and infection overlap clinically. Purulence, progression, systemic findings and wound assessment help distinguish them.

MRCS exam pearl

Neutrophils early; macrophages later. Exudate and transudate have different mechanisms.

3. Chronic inflammation, granulomas and giant cells

Chronic inflammation features mononuclear cells (macrophages, lymphocytes and plasma cells), tissue destruction and attempts at repair with angiogenesis and fibrosis. Granulomas are organised aggregates of epithelioid macrophages, sometimes with multinucleated giant cells. Caseating necrosis supports tuberculosis in an appropriate setting, but granuloma morphology alone is not absolutely diagnostic.

Clinical application

A draining sinus around a retained foreign material may show a foreign-body granulomatous reaction. Infection and implanted-material reaction can coexist; clinical sampling and context still matter.

MRCS exam pearl

Granuloma is a histological pattern, not automatically tuberculosis or malignancy.

4. Haemostasis and early wound signalling

Following injury, vasoconstriction, platelet adhesion/aggregation and a fibrin clot provide haemostasis. Platelets release signalling molecules including PDGF and TGF-beta, promoting cell recruitment and tissue repair. Coagulation and inflammation overlap rather than occurring as isolated time blocks; tissue oxygenation and perfusion are prerequisites for effective repair.

Clinical application

Haematoma, continued bleeding and uncontrolled dead space may increase tension or infection risk after surgery. Mechanical haemostasis and removal of devitalised tissue support subsequent healing.

MRCS exam pearl

Do not confuse fibrin clot (early matrix) with mature collagen scar.

5. The four overlapping phases of wound healing

The useful framework is haemostasis (immediate), inflammation (approximately first days), proliferation (begins within days and continues for weeks), then remodelling (weeks to months or longer). Timing varies with wound type and host factors. Granulation tissue contains newly formed capillaries, fibroblasts and loose extracellular matrix. Re-epithelialisation restores surface cover; myofibroblasts facilitate contraction.

Clinical application

An open wound may contract as it granulates; a clean sutured incision heals with less granulation volume and less contraction. Persistent contamination may keep a wound trapped in inflammation.

MRCS exam pearl

These phases overlap. A day-by-day timetable is an approximation, not a biological stopwatch.

Figure 1. Stages overlap; durations vary with patient, wound and complications.

6. Fibroblasts, collagen and tensile strength

Fibroblasts synthesize extracellular matrix and collagen. Early scar contains a relatively higher proportion of type III collagen; remodelling increases stronger type I collagen and cross-linking. Vitamin C is required for hydroxylation steps in collagen synthesis. Tensile strength increases progressively but a mature scar typically does not regain the full strength of uninjured skin, reaching roughly 70–80% in many teaching models.

Clinical application

A patient with malnutrition or scurvy may have bleeding, fragile tissue and delayed repair. Adequate protein and correction of deficiencies matter more than indiscriminate supplementation.

MRCS exam pearl

Do not claim that a healed scar becomes 100% as strong as normal skin.

7. Primary, secondary and delayed primary intention

Primary intention: clean wound edges are approximated, with limited tissue loss and scar. Secondary intention: the defect remains open and closes by granulation, epithelial migration and contraction; it generally takes longer and leaves a larger scar. Delayed primary (tertiary) closure: a contaminated or high-risk wound is initially managed open, then closed after reassessment and appropriate control of contamination.

Clinical application

A heavily contaminated traumatic wound may be left open rather than primarily closed. The decision depends on vascularity, depth, contamination, tissue viability and timing.

MRCS exam pearl

Delayed primary closure is planned later closure, not a wound that accidentally dehisces.

Figure 2. Delayed primary closure is a planned clinical strategy, not accidental dehiscence.

8. Factors that delay healing and how to optimise them

Local factors include ischaemia, excessive tension, infection, oedema, foreign material, necrosis and inadequate off-loading. Systemic factors include uncontrolled diabetes, smoking, malnutrition, immunosuppression and some therapies. Assess perfusion, glycaemic status, nutrition, wound load and medication. A chronic ulcer requires identifying its cause rather than applying dressings alone.

Clinical application

Arterial disease causes distal, painful poorly perfused lesions; venous hypertension typically causes gaiter-area ulcers with oedema and skin changes; neuropathy plus pressure drives plantar diabetic ulcers.

MRCS exam pearl

Antibiotics cannot fix critical ischaemia; topical products cannot substitute for pressure off-loading.

9. Surgical site infection and wound classes

SSI is categorised by anatomic depth: superficial incisional (skin/subcutaneous), deep incisional (fascia/muscle), and organ/space (an operated cavity or deeper body space). CDC/NHSN surveillance criteria also require procedure-specific timing and case definitions. Traditional operative wound classes describe clean, clean-contaminated, contaminated and dirty/infected wounds; these classes estimate infection risk but are not themselves a diagnosis.

Clinical application

Assess the patient and surgical site for systemic illness, collection, devitalised tissue and deeper involvement. Source control/drainage and appropriate targeted antimicrobials are considered where indicated, according to current protocols.

MRCS exam pearl

Do not classify a postoperative intra-abdominal abscess as superficial SSI.

Figure 3. Anatomical categories are distinct. Formal CDC/NHSN SSI reporting has additional surveillance criteria.

10. Dehiscence, evisceration, seroma and haematoma

Dehiscence means separation of previously approximated wound layers; superficial separation differs from failure of the abdominal fascial layer. Evisceration is protrusion of internal contents through disrupted fascial closure and is an emergency. Seroma is a serous fluid collection; haematoma is blood collection. Both can contribute to tension and wound complications but are not synonymous with infection.

Clinical application

A postoperative abdominal wound with sudden serosanguinous discharge and a visible fascial defect needs urgent surgical evaluation. Support protruding viscera appropriately and follow emergency management principles.

MRCS exam pearl

Seroma is not automatically pus. Fascial dehiscence and evisceration are more serious than superficial skin separation.

11. Hypertrophic scars, keloids and contractures

Hypertrophic scars remain within original wound boundaries and may flatten with time; keloids extend beyond the original margins and are more likely to persist or recur. Scar contracture restricts movement, especially after burns across joints. Tissue tension, host predisposition and persistent inflammation influence abnormal scarring.

Clinical application

Counsel about realistic outcomes. Silicone-based scar care, pressure or intralesional therapies may be considered for selected established scars; excision alone can recur for keloids and requires specialist judgement.

MRCS exam pearl

Keloid extends beyond the original wound; hypertrophic scar stays inside it.

12. High-yield pathology patterns and examiner traps

Necrosis after severe ischaemia usually follows a coagulative pattern in solid organs except brain, which commonly undergoes liquefactive necrosis. Abscesses are associated with liquefactive destruction. Fat necrosis can occur in pancreatitis, with calcium soap formation. Apoptosis is regulated cell death usually without the prominent inflammatory response of necrosis. Ulcers and chronic wounds may exhibit prolonged inflammation and impaired repair.

Clinical application

For vignette questions, decide whether the stem tests a cell, collagen type, injury pattern, site-infection depth, vascular insufficiency, or clinical emergency before choosing an answer.

MRCS exam pearl

Caseous, liquefactive, coagulative and fat necrosis are not interchangeable.

52-topic interactive revision checklist

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Core pathology

Hypertrophy versus hyperplasiaAtrophy and metaplasiaReversible versus irreversible cell injuryRegeneration versus fibrosis

Acute inflammation

Vasodilatation and permeabilityExudate versus transudateNeutrophil sequence in acute inflammationSelectin rolling and integrin adhesionChemotaxis and leukocyte migration

Chronic inflammation

Macrophages and lymphocytesGranuloma formationCaseating versus noncaseating granulomaForeign-body giant cells

Haemostasis

Platelet aggregation and fibrin clotPDGF and TGF-betaHaematoma and mechanical haemostasisClot as a provisional matrix

Healing phases

Haemostasis stageInflammation stageFibroblast proliferation and angiogenesisEpithelial migration and wound contractionRemodelling and scar maturation

Collagen

Early type III versus mature type I collagenHydroxylation and vitamin CFibroblast/myofibroblast rolesTensile strength over time

Intention

Primary intentionSecondary intentionDelayed primary closureWhy contaminated wounds may be left open

Poor healing

Diabetes and glycaemic controlIschaemia and perfusionSmoking and tissue oxygenationProtein and micronutrient deficiencyForeign material, tension and oedema

Infection

Clean/clean-contaminated wound classesContaminated and dirty/infected classesSuperficial incisional SSIDeep incisional SSIOrgan/space SSI

Complications

Seroma versus haematomaSuperficial wound separationFascial dehiscence and eviscerationNeed for urgent surgical assessment

Scar disorders

Hypertrophic scar versus keloidScar contracture and joint mobilityKeloid recurrence and management

Applied pathology

Coagulative necrosisLiquefactive necrosisCaseous necrosisFat necrosisApoptosis versus necrosis

40 original MRCS clinical single-best-answer questions

Each question has five choices (A–E), a single best answer and an explanation for every option. Answers are balanced across A–E. Your marked answers, correct score, review position and checklist are stored locally.

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Question 1 of 40

Question 1 of 40 • Cellular adaptation

Q01. A patient with long-standing hypertension develops increased left ventricular mass caused predominantly by enlargement of existing cardiomyocytes. What is this adaptation?

A. HypertrophyB. HyperplasiaC. MetaplasiaD. DysplasiaE. Atrophy

View detailed explanation, examiner trap and viva

Correct answer: A. Hypertrophy

Why correct: Mature cardiomyocytes largely increase their size in response to pressure loading.

Why the other options are incorrect:

B. Hyperplasia: Increased cell number, not the principal adaptation here.

C. Metaplasia: Replacement of one differentiated cell type by another.

D. Dysplasia: Disordered epithelial maturation rather than adaptive muscle enlargement.

E. Atrophy: Reduced cell size and tissue mass.

Exam pearl: Cardiac pressure overload primarily causes hypertrophy.

Examiner trap: Do not assume every organ enlarges by proliferation.

Viva extension — Name one hormone-responsive hyperplasia. Answer: Endometrial glandular hyperplasia after unopposed oestrogen exposure.

Question 2 of 40 • Cellular injury

Q02. A renal tubular cell exposed to brief hypoxia becomes swollen but recovers after perfusion improves. Which is the best description?

A. Coagulative necrosisB. Reversible cell injuryC. ApoptosisD. Caseous necrosisE. Metaplasia

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Correct answer: B. Reversible cell injury

Why correct: ATP depletion disturbs ion pumps and produces potentially reversible hydropic swelling.

Why the other options are incorrect:

A. Coagulative necrosis: Irreversible cell death with preserved outlines initially.

C. Apoptosis: Programmed cellular deletion, not transient reversible swelling.

D. Caseous necrosis: Necrotic granulomatous tissue, not reversible injury.

E. Metaplasia: Change in cell differentiation, not acute swelling.

Exam pearl: Cell swelling is an early marker of reversible injury.

Examiner trap: Swelling does not itself prove irreversible necrosis.

Viva extension — What indicates irreversible injury? Answer: Severe membrane and mitochondrial damage with necrotic cell death.

Question 3 of 40 • Acute inflammation

Q03. A wound shows prominent neutrophil recruitment during the first postoperative day. Which cell type is usually the earliest dominant leukocyte in acute bacterial inflammation?

A. EosinophilB. Plasma cellC. NeutrophilD. FibroblastE. Macrophage

View detailed explanation, examiner trap and viva

Correct answer: C. Neutrophil

Why correct: Neutrophils are typically recruited rapidly to acute bacterial inflammation.

Why the other options are incorrect:

A. Eosinophil: Prominent in allergy and some parasitic responses.

B. Plasma cell: An antibody-producing mature B cell, typical of chronic responses.

D. Fibroblast: Repairs matrix rather than dominating initial leukocyte infiltrate.

E. Macrophage: Crucial later and in coordination of repair, not usually first dominant cell.

Exam pearl: Neutrophils first, then monocytes/macrophages commonly follow.

Examiner trap: Histological timing depends on cause and tissue.

Viva extension — Which cell transitions inflammation to repair? Answer: Activated macrophages through cytokines and growth factors.

Question 4 of 40 • Inflammatory mediators

Q04. An acute allergic reaction causes rapid increased capillary permeability and wheal formation. Which mediator is most responsible early?

A. ErythropoietinB. InsulinC. CalcitoninD. HistamineE. Thyroxine

View detailed explanation, examiner trap and viva

Correct answer: D. Histamine

Why correct: Mast-cell histamine rapidly increases vascular permeability and causes vasodilation.

Why the other options are incorrect:

A. Erythropoietin: Stimulates red-cell production.

B. Insulin: Regulates glucose metabolism rather than acute permeability.

C. Calcitonin: Involved in calcium homeostasis.

E. Thyroxine: Regulates metabolic activity, not the immediate wheal reaction.

Exam pearl: Histamine is an early vasoactive mediator.

Examiner trap: Prostaglandins contribute to pain/fever but are not the main immediate wheal mediator.

Viva extension — Give one cell that releases histamine. Answer: Mast cell.

Question 5 of 40 • Leukocyte recruitment

Q05. During acute inflammation, leukocytes first tether and roll along activated endothelium. Which adhesion-molecule family mediates rolling?

A. IntegrinsB. CadherinsC. CollagenasesD. Immunoglobulin EE. Selectins

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Correct answer: E. Selectins

Why correct: E- and P-selectins facilitate transient leukocyte rolling interactions.

Why the other options are incorrect:

A. Integrins: Firm adhesion is their major function after activation.

B. Cadherins: Primarily maintain cell-cell junctions.

C. Collagenases: Break down matrix, not rolling adhesion.

D. Immunoglobulin E: An antibody class relevant to allergy, not rolling.

Exam pearl: Rolling = selectins; firm adhesion = integrins.

Examiner trap: Do not reverse rolling and firm adhesion.

Viva extension — Which molecules support firm adhesion? Answer: Activated leukocyte integrins binding ICAM/VCAM.

Question 6 of 40 • Exudate and transudate

Q06. A patient has an acutely inflamed pleural surface with protein-rich fluid caused by increased endothelial permeability. What type of fluid is this?

A. ExudateB. TransudateC. ChyleD. Pure bloodE. Urine

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Correct answer: A. Exudate

Why correct: Inflammation increases permeability, allowing protein-rich fluid to leave vessels.

Why the other options are incorrect:

B. Transudate: Usually lower-protein fluid driven by hydrostatic/oncotic imbalance.

C. Chyle: Lymphatic lipid-rich fluid with a different mechanism.

D. Pure blood: A haemorrhage rather than typical inflammatory exudate.

E. Urine: Produced by renal excretion, not pleural inflammation.

Exam pearl: Exudate often reflects vascular permeability.

Examiner trap: An isolated fluid protein concentration must be interpreted by setting and tests.

Viva extension — What drives cardiac-failure transudates? Answer: Raised hydrostatic pressure.

Question 7 of 40 • Chronic inflammation

Q07. Biopsy of a chronic draining sinus reveals epithelioid macrophages and multinucleated giant cells around a suture fragment. The dominant pattern is what?

A. Acute neutrophilic cellulitisB. Foreign-body granulomatous inflammationC. Purely normal granulation tissueD. Coagulative infarctionE. Epithelial dysplasia

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Correct answer: B. Foreign-body granulomatous inflammation

Why correct: Macrophages organise around persistent foreign material and may fuse into giant cells.

Why the other options are incorrect:

A. Acute neutrophilic cellulitis: Does not best describe the granuloma/giant-cell pattern.

C. Purely normal granulation tissue: Fibroblasts/capillaries differ from a macrophage granuloma.

D. Coagulative infarction: Ischaemic cell death without this granulomatous pattern.

E. Epithelial dysplasia: Abnormal epithelial maturation, not macrophage reaction.

Exam pearl: A granuloma is a macrophage-rich organisation.

Examiner trap: Foreign-body granuloma does not exclude concomitant infection.

Viva extension — What is an epithelioid histiocyte? Answer: An activated macrophage with epithelial-like morphology.

Question 8 of 40 • Granuloma

Q08. A lymph-node biopsy shows epithelioid granulomas containing central amorphous necrotic debris in a patient with tuberculosis. What necrotic pattern is described?

A. Fat necrosisB. Liquefactive necrosisC. Caseous necrosisD. Coagulative necrosisE. Fibrinoid necrosis

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Correct answer: C. Caseous necrosis

Why correct: Caseating granulomas contain acellular cheese-like necrotic material in appropriate settings.

Why the other options are incorrect:

A. Fat necrosis: Fat digestion and saponification are different.

B. Liquefactive necrosis: Tissue liquefaction is typical of abscesses/brain infarcts.

D. Coagulative necrosis: Preserved tissue outlines typify most solid-organ infarcts.

E. Fibrinoid necrosis: Vessel wall immune injury yields bright fibrin-like material.

Exam pearl: Caseation supports, but does not alone prove, tuberculosis.

Examiner trap: Not every granuloma is caseating.

Viva extension — Which additional investigations might support TB? Answer: Microbiology/histology contextual assessment including culture or molecular testing.

Question 9 of 40 • Haemostasis

Q09. Immediately after an incision is made, a platelet plug and fibrin mesh form. This represents which wound-healing phase?

A. RemodellingB. AngiogenesisC. ContractureD. HaemostasisE. Epithelial differentiation

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Correct answer: D. Haemostasis

Why correct: Platelets and coagulation stabilise the initial wound and generate a provisional matrix.

Why the other options are incorrect:

A. Remodelling: Late collagen reorganisation occurs weeks or months later.

B. Angiogenesis: New vessel growth is part of proliferation.

C. Contracture: Myofibroblast contraction is later.

E. Epithelial differentiation: Surface restoration happens during proliferation.

Exam pearl: Haemostasis begins immediately.

Examiner trap: Fibrin is not mature type I collagen.

Viva extension — Which platelet-derived mediator promotes repair? Answer: Platelet-derived growth factor (PDGF).

Question 10 of 40 • Wound phases

Q10. A clean sutured skin incision develops capillary buds, fibroblasts and a soft vascular wound bed on postoperative day 5. Which phase is prominent?

A. Haemostatic phase onlyB. Final maturation onlyC. Irreversible necrosisD. MetaplasiaE. Proliferative phase

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Correct answer: E. Proliferative phase

Why correct: Fibroblast growth, angiogenesis and granulation tissue define proliferation.

Why the other options are incorrect:

A. Haemostatic phase only: Clot formation is immediate and does not describe day-5 granulation.

B. Final maturation only: Remodelling occurs later with collagen reorganisation.

C. Irreversible necrosis: Cell death is not the normal new-vessel process.

D. Metaplasia: Cell lineage replacement is unrelated.

Exam pearl: Granulation tissue = capillaries + fibroblasts + loose ECM.

Examiner trap: Phase timing overlaps; choose the dominant biological event.

Viva extension — What is epithelialisation? Answer: Migration and proliferation of epithelial cells over the wound surface.

Question 11 of 40 • Macrophage role

Q11. Which cell is especially important for coordinating the transition from early inflammation to subsequent tissue repair?

A. MacrophageB. ErythrocyteC. OsteoclastD. KeratinocyteE. Mature adipocyte

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Correct answer: A. Macrophage

Why correct: Macrophages clear debris and release signals that recruit fibroblasts and support angiogenesis.

Why the other options are incorrect:

B. Erythrocyte: Provides oxygen transport but is not the repair coordinator.

C. Osteoclast: Resorbs bone, not the primary skin-wound coordinator.

D. Keratinocyte: Provides epithelial cover rather than primary macrophage coordination.

E. Mature adipocyte: Stores lipids and does not dominate this repair signalling.

Exam pearl: Macrophages bridge inflammation and repair.

Examiner trap: A macrophage is not a fibroblast.

Viva extension — Name a macrophage-associated profibrotic signal. Answer: TGF-beta is one.

Question 12 of 40 • Granulation tissue

Q12. A pink, soft, friable tissue fills a granulating wound after debridement. What microscopic features are expected?

A. Dense avascular mature collagen onlyB. Numerous small capillaries with fibroblasts and loose extracellular matrixC. Sheets of cartilage cellsD. Stratified keratin aloneE. Pure fibrin without vessels

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Correct answer: B. Numerous small capillaries with fibroblasts and loose extracellular matrix

Why correct: These constitute the classical cellular and vascular components of granulation tissue.

Why the other options are incorrect:

A. Dense avascular mature collagen only: Would suggest mature fibrous scar rather than granulation.

C. Sheets of cartilage cells: Not characteristic of ordinary skin-wound repair.

D. Stratified keratin alone: Describes surface epithelium, not granulation bed.

E. Pure fibrin without vessels: Represents early provisional matrix rather than granulation tissue.

Exam pearl: Granulation tissue is vascular and often bleeds easily.

Examiner trap: Granulation tissue is not a granuloma.

Viva extension — Define a granuloma. Answer: Organised aggregate of activated macrophages, often with giant cells.

Question 13 of 40 • Wound contraction

Q13. An open wound gets smaller because cells pull its edges centripetally. Which cells provide this contractile activity?

A. NeutrophilsB. MelanocytesC. MyofibroblastsD. PlateletsE. Osteocytes

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Correct answer: C. Myofibroblasts

Why correct: Myofibroblasts express contractile proteins and reduce wound area.

Why the other options are incorrect:

A. Neutrophils: Early inflammatory cells with no major wound-pulling role.

B. Melanocytes: Pigment-producing cells.

D. Platelets: Contribute haemostasis, not prolonged contraction.

E. Osteocytes: Bone-resident cells.

Exam pearl: Secondary-intention wounds contract strongly.

Examiner trap: Contraction is different from epithelial migration.

Viva extension — Which protein enables myofibroblast contraction? Answer: Alpha-smooth muscle actin.

Question 14 of 40 • Collagen types

Q14. Which collagen type is relatively prominent in newly deposited early granulation matrix before scar remodelling?

A. Type II collagenB. Type IV collagenC. Type I only from the outsetD. Type III collagenE. Type VII collagen

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Correct answer: D. Type III collagen

Why correct: Type III collagen is an important early deposited form before mature type I predominance.

Why the other options are incorrect:

A. Type II collagen: Typical of hyaline cartilage.

B. Type IV collagen: Major component of basement membranes.

C. Type I only from the outset: Type I becomes more dominant with maturation.

E. Type VII collagen: Anchoring fibrils at epidermal junctions.

Exam pearl: Early type III later replaced by type I.

Examiner trap: Type IV is basement membrane collagen.

Viva extension — Which collagen predominates in mature skin scar? Answer: Type I collagen.

Question 15 of 40 • Maturation

Q15. Several months after surgery, a scar becomes paler and stronger as collagen is reorganised and cross-linked. Which phase dominates?

A. Immediate haemostasisB. Acute exudative responseC. Leukocyte rollingD. Primary coagulationE. Remodelling and maturation

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Correct answer: E. Remodelling and maturation

Why correct: Collagen organisation and tensile strength gain characterise this later phase.

Why the other options are incorrect:

A. Immediate haemostasis: Platelet plug formation is early.

B. Acute exudative response: Predominates soon after injury.

C. Leukocyte rolling: An early inflammatory recruitment event.

D. Primary coagulation: Occurs at initial vascular injury.

Exam pearl: Scar strength increases over months.

Examiner trap: Remodelling does not restore original 100% strength.

Viva extension — Roughly what maximum skin-scar strength is often taught? Answer: Approximately 70–80% of uninjured skin, variable by wound and tissue.

Question 16 of 40 • Vitamin deficiency

Q16. A malnourished patient has gingival bleeding and poor wound healing. Which micronutrient deficiency most directly impairs proline and lysine hydroxylation during collagen synthesis?

A. Vitamin CB. Vitamin B12C. Vitamin KD. Vitamin DE. Vitamin A

View detailed explanation, examiner trap and viva

Correct answer: A. Vitamin C

Why correct: Ascorbate is required for collagen prolyl/lysyl hydroxylation; deficiency causes scurvy.

Why the other options are incorrect:

B. Vitamin B12: Important in DNA synthesis and neurologic function.

C. Vitamin K: Involved in gamma-carboxylation of coagulation proteins.

D. Vitamin D: Mainly regulates calcium/phosphate and bone metabolism.

E. Vitamin A: Important in epithelial differentiation but not this hydroxylation reaction.

Exam pearl: Scurvy = poor collagen + bleeding gums.

Examiner trap: Do not confuse vitamin C with vitamin K coagulation deficiency.

Viva extension — Name the modified residues involved. Answer: Hydroxyproline and hydroxylysine.

Question 17 of 40 • Primary healing

Q17. A clean elective surgical incision is closed edge-to-edge with little tissue loss and minimal separation. By which intention does it heal?

A. Secondary intentionB. Primary intentionC. Delayed primary intentionD. Pathological keloid healingE. Regeneration without any scar in all layers

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Correct answer: B. Primary intention

Why correct: Approximation allows rapid epithelial bridging with a relatively small defect to repair.

Why the other options are incorrect:

A. Secondary intention: Applies to a wound left open with granulation and contraction.

C. Delayed primary intention: Closure occurs after initial open management.

D. Pathological keloid healing: An abnormal scar, not a closure-intention category.

E. Regeneration without any scar in all layers: Deep dermal injury typically produces some scar.

Exam pearl: Primary intention = approximated clean edges.

Examiner trap: Primary intention can still be complicated by infection.

Viva extension — What is secondary intention? Answer: Open wound closes via granulation, contraction and epithelial migration.

Question 18 of 40 • Secondary healing

Q18. A pressure injury has significant tissue loss and remains open while filling with granulation tissue. Which healing mechanism is expected?

A. Primary intentionB. Tertiary immediate closureC. Secondary intentionD. Intramembranous ossificationE. Metaplasia

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Correct answer: C. Secondary intention

Why correct: An unapproximated tissue defect granulates and contracts before epithelial cover completes.

Why the other options are incorrect:

A. Primary intention: Would require suitable immediate approximation of edges.

B. Tertiary immediate closure: Tertiary involves planned delayed closure.

D. Intramembranous ossification: Bone mechanism unrelated to skin closure.

E. Metaplasia: Cell type substitution not closure mode.

Exam pearl: Secondary healing needs more contraction and often more scar.

Examiner trap: Closure type is not the same as infection classification.

Viva extension — What promotes the size reduction? Answer: Myofibroblast-mediated contraction.

Question 19 of 40 • Delayed closure

Q19. A heavily contaminated traumatic wound is debrided and managed open for reassessment before planned later closure. What is this called?

A. Immediate primary intentionB. Secondary intention onlyC. Keloid formationD. Delayed primary (tertiary) intentionE. Acute graft rejection

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Correct answer: D. Delayed primary (tertiary) intention

Why correct: After control of contamination and review of viability, selected wounds can undergo planned subsequent closure.

Why the other options are incorrect:

A. Immediate primary intention: Would close at the first procedure.

B. Secondary intention only: Would let the open wound close fully without later approximation.

C. Keloid formation: An excessive scar complication.

E. Acute graft rejection: Unrelated to traumatic-wound closure timing.

Exam pearl: Delayed primary = open first, close later when appropriate.

Examiner trap: Do not equate dehiscence with planned delayed closure.

Viva extension — Name one reason to defer closure. Answer: Persistent contamination or uncertainty about tissue viability.

Question 20 of 40 • Healing factors

Q20. An ulcer remains open despite frequent topical antibiotics; examination reveals absent distal pulses and a cold foot. What fundamental barrier to healing should be addressed?

A. Excess epithelialisationB. High vitamin C intakeC. Excessively rapid remodellingD. Normal vascular supplyE. Inadequate arterial perfusion

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Correct answer: E. Inadequate arterial perfusion

Why correct: Tissue oxygenation and nutrient delivery are critical; critical ischaemia blocks effective repair.

Why the other options are incorrect:

A. Excess epithelialisation: The ulcer demonstrates inadequate, not excessive, closure.

B. High vitamin C intake: Not the principal issue given absent pulses.

C. Excessively rapid remodelling: Not a plausible explanation.

D. Normal vascular supply: Contradicted by clinical findings.

Exam pearl: Perfusion before dressings in ischaemic ulcers.

Examiner trap: Antibiotics alone cannot revascularise a limb.

Viva extension — Which assessment may help? Answer: Vascular examination and objective arterial perfusion testing.

Question 21 of 40 • Diabetes and healing

Q21. Which systemic factor is most likely to impair leukocyte function and increase postoperative wound infection risk if poorly controlled?

A. Diabetes with hyperglycaemiaB. Normal haemoglobin concentrationC. Adequate protein intakeD. Normal peripheral perfusionE. Absence of infection

View detailed explanation, examiner trap and viva

Correct answer: A. Diabetes with hyperglycaemia

Why correct: Persistent hyperglycaemia impairs immune response and contributes to vascular/repair problems.

Why the other options are incorrect:

B. Normal haemoglobin concentration: Does not explain infection vulnerability.

C. Adequate protein intake: Supports rather than impairs healing.

D. Normal peripheral perfusion: Usually beneficial.

E. Absence of infection: Does not elevate SSI risk.

Exam pearl: Optimise glycaemia without triggering hypoglycaemia.

Examiner trap: Risk is multifactorial, not only blood sugar.

Viva extension — Name another modifiable risk. Answer: Smoking cessation or nutritional optimisation.

Question 22 of 40 • Clean surgery

Q22. An elective uncomplicated hernia repair is performed without entry into respiratory, alimentary, genital or infected urinary tracts. Traditional wound class?

A. Clean-contaminatedB. CleanC. ContaminatedD. Dirty/infectedE. Organ-space infection

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Correct answer: B. Clean

Why correct: Uninfected surgery without entry into colonised tracts usually meets clean-class criteria.

Why the other options are incorrect:

A. Clean-contaminated: Controlled entry into colonised hollow viscera.

C. Contaminated: Major break in sterile technique or gross spillage.

D. Dirty/infected: Existing infection or devitalised infected tissue.

E. Organ-space infection: Postoperative complication category, not wound class.

Exam pearl: Classifying the operative field is separate from diagnosing SSI.

Examiner trap: Even clean operations can develop an SSI.

Viva extension — Give one clean-contaminated example. Answer: Controlled bowel entry without gross spillage.

Question 23 of 40 • Clean-contaminated

Q23. A planned colectomy involves controlled bowel entry without gross spillage or established infection. Which operative wound class best fits?

A. CleanB. ContaminatedC. Clean-contaminatedD. Dirty/infectedE. Superficial SSI

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Correct answer: C. Clean-contaminated

Why correct: Controlled entry into a colonised viscus without major contamination is class II.

Why the other options are incorrect:

A. Clean: Bowel lumen entry excludes the clean category.

B. Contaminated: Gross contamination or major sterile breach is lacking.

D. Dirty/infected: No established infection or old infected wound.

E. Superficial SSI: A postoperative event rather than an operative wound class.

Exam pearl: Controlled bowel entry = clean-contaminated.

Examiner trap: Do not confuse wound class with postoperative infection depth.

Viva extension — What changes classification toward contaminated? Answer: Gross spillage or major sterile technique break.

Question 24 of 40 • Dirty wound

Q24. A laparotomy finds a perforated bowel with established peritonitis. Which traditional surgical wound class is most appropriate?

A. CleanB. Clean-contaminatedC. Simple contaminated onlyD. Dirty/infectedE. Unclassifiable by definition

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Correct answer: D. Dirty/infected

Why correct: Existing infection and perforated hollow viscus with established peritonitis are class IV.

Why the other options are incorrect:

A. Clean: An infected peritoneal cavity is not clean.

B. Clean-contaminated: There is uncontrolled infected contamination.

C. Simple contaminated only: Established infection/perforation supports dirty-infected classification.

E. Unclassifiable by definition: It is classifiable under traditional classes.

Exam pearl: Perforated infected viscera = dirty/infected.

Examiner trap: Contaminated versus dirty hinges on existing infection/old infection and perforation context.

Viva extension — Why is wound class important? Answer: It informs SSI risk assessment and prevention strategy.

Question 25 of 40 • SSI anatomy

Q25. A patient develops purulent discharge from only the skin and subcutaneous portion of a laparotomy incision, with deeper fascia intact. Which SSI category?

A. Deep incisional SSIB. Organ/space SSIC. KeloidD. SeromaE. Superficial incisional SSI

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Correct answer: E. Superficial incisional SSI

Why correct: Superficial incisional SSI involves the skin/subcutaneous incision layers when formal criteria are met.

Why the other options are incorrect:

A. Deep incisional SSI: Involves deep soft tissues such as fascia and muscle.

B. Organ/space SSI: Involves deeper operated organ or body space.

C. Keloid: An abnormal mature scar, not purulent infection.

D. Seroma: Sterile serous fluid without this purulent pattern.

Exam pearl: SSI depth is defined by involved anatomy.

Examiner trap: Use CDC formal criteria and surveillance periods for reporting.

Viva extension — What tissues define deep incisional SSI? Answer: Fascia and muscle layers.

Question 26 of 40 • Deep SSI

Q26. After colorectal surgery, a purulent collection is discovered within the fascial and muscular incision layers without an intra-abdominal collection. Which class?

A. Deep incisional SSIB. Superficial incisional SSIC. Organ/space SSID. Cellular hyperplasiaE. Seroma alone

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Correct answer: A. Deep incisional SSI

Why correct: Fascial or muscular incision involvement is deep incisional rather than superficial or organ-space.

Why the other options are incorrect:

B. Superficial incisional SSI: Only skin/subcutaneous layers.

C. Organ/space SSI: Would involve the operated internal organ/space beyond the incision.

D. Cellular hyperplasia: Not infection classification.

E. Seroma alone: Would not explain a proven purulent deep collection.

Exam pearl: Deep incisional = fascia/muscle.

Examiner trap: A separate peritoneal abscess is organ/space, not merely deep incisional.

Viva extension — Why might drainage be needed? Answer: A purulent collection generally requires source-control assessment.

Question 27 of 40 • Organ-space SSI

Q27. A patient develops a postoperative intra-abdominal abscess following bowel resection while the skin incision is unremarkable. Which SSI level is implicated?

A. Superficial incisional SSIB. Organ/space SSIC. Deep incisional SSID. HaematomaE. Hypertrophic scar

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Correct answer: B. Organ/space SSI

Why correct: A postoperative infection within the surgically entered/manipulated intra-abdominal space is organ/space SSI if surveillance criteria are fulfilled.

Why the other options are incorrect:

A. Superficial incisional SSI: Skin and subcutaneous tissue only.

C. Deep incisional SSI: Fascia/muscle of the incision.

D. Haematoma: Blood collection, not an infected intra-abdominal abscess.

E. Hypertrophic scar: Scar excess, not internal infection.

Exam pearl: An incision can appear normal in organ/space SSI.

Examiner trap: Do not classify abscess depth by skin appearance alone.

Viva extension — What is an important management principle? Answer: Assess for drainage/source control and sepsis treatment.

Question 28 of 40 • Wound complications

Q28. A surgical drain has been removed. A non-purulent, clear straw-coloured collection develops beneath the incision. What is most likely?

A. HaematomaB. Purulent abscessC. SeromaD. EviscerationE. Keloid

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Correct answer: C. Seroma

Why correct: Seroma is a collection of serous fluid that may develop in postoperative dead space.

Why the other options are incorrect:

A. Haematoma: Blood-rich fluid collection.

B. Purulent abscess: Infected collection, typically pus rather than clear straw fluid.

D. Evisceration: Protrusion of viscera from fascial disruption.

E. Keloid: Excess collagen extending beyond wound margins.

Exam pearl: Seroma and infection are not synonymous.

Examiner trap: A suspected infected collection needs clinical evaluation despite initial appearance.

Viva extension — What promotes seroma formation? Answer: Dead space and lymphatic disruption.

Question 29 of 40 • Abdominal dehiscence

Q29. On day 8 after laparotomy, a patient suddenly develops large serosanguinous wound drainage and the fascia has separated. What complication is this?

A. Superficial skin-only separationB. Routine epithelial migrationC. Hypertrophic scarD. Fascial wound dehiscenceE. Simple seroma without dehiscence

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Correct answer: D. Fascial wound dehiscence

Why correct: Disruption of the deeper abdominal-wall closure produces fascial dehiscence and needs urgent assessment.

Why the other options are incorrect:

A. Superficial skin-only separation: The stem documents fascial disruption.

B. Routine epithelial migration: Cannot account for opening fascia.

C. Hypertrophic scar: Occurs with scar maturation, not acute fascial opening.

E. Simple seroma without dehiscence: Does not explain separated fascia.

Exam pearl: Sudden serosanguinous discharge can precede fascial failure.

Examiner trap: Do not reassure based on only a clean-looking skin edge.

Viva extension — What is evisceration? Answer: Extrusion of abdominal viscera through a disrupted abdominal closure.

Question 30 of 40 • Evisceration

Q30. A patient after laparotomy has bowel loops protruding through an open abdominal wound. What is the immediate clinical interpretation?

A. Routine wound granulationB. Simple superficial seromaC. KeloidD. Uncomplicated primary healingE. Evisceration requiring urgent surgical assessment

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Correct answer: E. Evisceration requiring urgent surgical assessment

Why correct: Visceral protrusion through fascial failure is an emergency requiring protection of exposed bowel and urgent management.

Why the other options are incorrect:

A. Routine wound granulation: Granulation does not protrude as bowel loops.

B. Simple superficial seroma: No visceral protrusion.

C. Keloid: Late scar overgrowth, not this event.

D. Uncomplicated primary healing: Directly contradicted by open abdomen with bowel.

Exam pearl: Evisceration is a surgical emergency.

Examiner trap: Do not attempt casual bedside reduction without appropriate assessment.

Viva extension — How should exposed viscera initially be protected? Answer: Sterile saline-moistened protective dressings while urgent surgical help is arranged.

Question 31 of 40 • Scar biology

Q31. A firm raised postoperative scar remains within the exact original incision margins and slowly flattens. Which is most likely?

A. Hypertrophic scarB. KeloidC. AbscessD. SeromaE. Lipoma

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Correct answer: A. Hypertrophic scar

Why correct: Hypertrophic scar remains confined within original wound borders and may regress.

Why the other options are incorrect:

B. Keloid: Extends beyond original wound margins.

C. Abscess: Infected purulent collection, not stable raised scar.

D. Seroma: Fluid collection, not collagen-rich scar.

E. Lipoma: Benign adipose mass unrelated to wound-edge pattern.

Exam pearl: Hypertrophic within; keloid beyond.

Examiner trap: Both may itch, so use wound boundaries.

Viva extension — Which scar is more likely to recur after excision alone? Answer: Keloid.

Question 32 of 40 • Keloid

Q32. An ear-piercing scar expands for months beyond the margins of the initial puncture. Which diagnosis best fits?

A. Hypertrophic scarB. KeloidC. Granulation tissueD. SeromaE. Coagulative necrosis

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Correct answer: B. Keloid

Why correct: Keloids overgrow the original wound boundary and may persist or recur.

Why the other options are incorrect:

A. Hypertrophic scar: Usually stays within wound boundaries.

C. Granulation tissue: Early vascular wound bed rather than mature extending scar.

D. Seroma: A fluid collection.

E. Coagulative necrosis: Ischaemic cell death, not collagen scar overgrowth.

Exam pearl: Keloid can extend beyond injury.

Examiner trap: Do not equate keloid recurrence with infection.

Viva extension — Why might surgery alone be insufficient? Answer: Excision can be followed by recurrence; multimodal specialist approaches may be used.

Question 33 of 40 • Burn contracture

Q33. A healed burn crossing the elbow leaves skin tightening and loss of extension. What pathological process causes this limitation?

A. Pure haemostasisB. Isolated transudateC. Scar contractureD. Physiological vasodilationE. Acute mast-cell degranulation

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Correct answer: C. Scar contracture

Why correct: Contraction of fibrous repair tissue can tether and restrict motion across a joint.

Why the other options are incorrect:

A. Pure haemostasis: An early clot cannot explain late fixed restriction.

B. Isolated transudate: Fluid-pressure phenomenon not scar shortening.

D. Physiological vasodilation: Does not create fixed scar contracture.

E. Acute mast-cell degranulation: Not responsible for mature motion restriction.

Exam pearl: Joint-crossing burns risk contracture.

Examiner trap: Contraction helps close wounds but can be functionally disabling.

Viva extension — How can rehabilitation help? Answer: Appropriate positioning, splinting and movement therapy as clinically indicated.

Question 34 of 40 • Necrosis patterns

Q34. A myocardial infarct shows preserved tissue outlines but loss of cell nuclei in the first days. What necrotic pattern is typical?

A. Liquefactive necrosisB. Caseous necrosisC. Fat necrosisD. Coagulative necrosisE. Fibrinoid necrosis

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Correct answer: D. Coagulative necrosis

Why correct: Ischaemic necrosis in most solid organs causes temporary retention of tissue architecture.

Why the other options are incorrect:

A. Liquefactive necrosis: More typical of cerebral infarction and abscess.

B. Caseous necrosis: Granulomatous infection such as TB.

C. Fat necrosis: Lipase-related or traumatic adipose tissue injury.

E. Fibrinoid necrosis: Often a vessel-wall injury pattern.

Exam pearl: Solid-organ infarcts usually coagulative; brain is exception.

Examiner trap: Brain infarction differs from myocardium.

Viva extension — What pattern follows cerebral infarction? Answer: Liquefactive necrosis.

Question 35 of 40 • Brain necrosis

Q35. A patient suffers a large cerebral infarction. Which pattern of tissue destruction is classically expected?

A. Coagulative necrosisB. Caseous necrosisC. Fat necrosisD. Fibrinoid necrosisE. Liquefactive necrosis

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Correct answer: E. Liquefactive necrosis

Why correct: Cerebral infarction characteristically leads to enzymatic digestion and tissue liquefaction.

Why the other options are incorrect:

A. Coagulative necrosis: Typical of infarcted heart/kidney, not most brain infarcts.

B. Caseous necrosis: Associated with granulomatous infection.

C. Fat necrosis: Occurs in adipose tissue/pancreatitis.

D. Fibrinoid necrosis: Vascular wall deposition pattern.

Exam pearl: Brain infarct = liquefactive necrosis.

Examiner trap: An abscess may also liquefy, but the stem is ischaemic brain.

Viva extension — What cellular mechanism helps liquefaction? Answer: Enzymatic digestion of necrotic tissue.

Question 36 of 40 • Pancreatitis

Q36. A patient with acute pancreatitis develops chalky white deposits in peripancreatic fat. Which process accounts for them?

A. Enzymatic fat necrosis with saponificationB. Coagulative myocardial infarctionC. Fibrinoid vascular necrosisD. Granuloma without necrosisE. Normal collagen cross-linking

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Correct answer: A. Enzymatic fat necrosis with saponification

Why correct: Pancreatic lipases release fatty acids that bind calcium forming soaps.

Why the other options are incorrect:

B. Coagulative myocardial infarction: Different tissue/mechanism.

C. Fibrinoid vascular necrosis: Vascular immune/pressure injury pattern.

D. Granuloma without necrosis: Macrophage aggregate does not explain fat saponification.

E. Normal collagen cross-linking: Physiological remodelling, not chalky deposits.

Exam pearl: Fat necrosis in pancreatitis may cause hypocalcaemia.

Examiner trap: Saponification is not type III collagen.

Viva extension — Why may calcium fall in severe pancreatitis? Answer: Calcium sequestration in fat saponification among other factors.

Question 37 of 40 • Apoptosis

Q37. Chemotherapy causes individual tumour cells to shrink and fragment into membrane-bound bodies without a prominent surrounding inflammatory response. What process?

A. Uncontrolled necrosisB. ApoptosisC. Cellular hypertrophyD. Coagulative ischaemic necrosisE. Granulation tissue formation

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Correct answer: B. Apoptosis

Why correct: Programmed cell death produces apoptotic bodies cleared with relatively little inflammation.

Why the other options are incorrect:

A. Uncontrolled necrosis: Usually membrane disruption and inflammation.

C. Cellular hypertrophy: Increased cell size rather than fragmentation.

D. Coagulative ischaemic necrosis: Not individual regulated cell death.

E. Granulation tissue formation: Repair matrix and vessel growth rather than cell deletion.

Exam pearl: Apoptosis is regulated and generally non-inflammatory.

Examiner trap: Apoptosis and necrosis are distinct processes but can coexist.

Viva extension — What enzymes drive many apoptotic pathways? Answer: Caspases.

Question 38 of 40 • Fibrinoid necrosis

Q38. A vasculitic small-artery biopsy shows intensely eosinophilic material within the vessel wall with vascular injury. This is which necrosis?

A. Fat necrosisB. Liquefactive necrosisC. Fibrinoid necrosisD. Caseous necrosisE. Coagulative infarction

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Correct answer: C. Fibrinoid necrosis

Why correct: Immune-mediated or severe vascular injury may deposit fibrin-like material in vessel walls.

Why the other options are incorrect:

A. Fat necrosis: Fat saponification, not vessel-wall eosinophilia.

B. Liquefactive necrosis: Tissue digestion into liquid debris.

D. Caseous necrosis: Necrotising granulomas.

E. Coagulative infarction: Preserved outlines of ischaemic parenchyma.

Exam pearl: Fibrinoid = vessel-wall pathology.

Examiner trap: Do not confuse the term fibrinoid with ordinary haemostatic fibrin clot.

Viva extension — Give a context for fibrinoid necrosis. Answer: Immune-mediated vasculitis.

Question 39 of 40 • Wound infection prevention

Q39. A patient is scheduled for elective surgery. Which perioperative action is a recognised measure within surgical site infection prevention pathways?

A. Deliberately induce hypothermiaB. Routine prolonged antibiotics for all clean surgeryC. Ignore perioperative glucose abnormalitiesD. Maintain perioperative normothermiaE. Close grossly contaminated tissue regardless of viability

View detailed explanation, examiner trap and viva

Correct answer: D. Maintain perioperative normothermia

Why correct: NICE NG125 recommends maintaining appropriate temperature during surgery to reduce avoidable complications.

Why the other options are incorrect:

A. Deliberately induce hypothermia: Can impair healing and increase complication risk.

B. Routine prolonged antibiotics for all clean surgery: Antibiotic use should follow specific prophylaxis indications and policies.

C. Ignore perioperative glucose abnormalities: Risk optimisation matters.

E. Close grossly contaminated tissue regardless of viability: Tissue viability and infection control must be considered.

Exam pearl: Normothermia is part of SSI prevention bundles.

Examiner trap: Do not equate preventive antibiotics with indefinite postoperative antibiotics.

Viva extension — Where should current SSI prevention guidance be checked? Answer: Current NICE NG125/local antimicrobial guidance.

Question 40 of 40 • Surgical infection management

Q40. A patient with a clinically significant infected postoperative wound has a fluctuant collection, fever and systemic illness. Which principle is most important alongside resuscitation and appropriate antibiotics?

A. Only increase dressing frequencyB. Automatically close the infected cavityC. Use antibiotics indefinitely without reassessmentD. Ignore systemic signs if wound looks smallE. Assess need for drainage and source control

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Correct answer: E. Assess need for drainage and source control

Why correct: Purulent collections and infected devitalised tissue may require drainage/debridement to control infection.

Why the other options are incorrect:

A. Only increase dressing frequency: May not address underlying infected collection.

B. Automatically close the infected cavity: Can trap infection.

C. Use antibiotics indefinitely without reassessment: Treatment should target cause and be reviewed.

D. Ignore systemic signs if wound looks small: Sepsis can occur with small surface appearances.

Exam pearl: Source control is central when an infected collection is present.

Examiner trap: Antibiotics are not a substitute for drainage in appropriate cases.

Viva extension — What determines antibiotic selection? Answer: Likely pathogens, source, severity and microbiology/local policy.

Frequently asked questions

Is this official MRCS recall content?

No. The article uses original, independently written educational questions that cover published syllabus topics, not confidential past examination content.

Which wound phase contains granulation tissue?

The proliferative phase, with fibroblasts, angiogenesis and extracellular-matrix deposition.

What is the best early scar collagen fact?

Early healing contains more type III collagen, with type I increasing during later remodelling.

How is a keloid different from a hypertrophic scar?

A keloid extends beyond the original wound, whereas a hypertrophic scar remains within it.

Can I retain my checklist and quiz score?

Yes, using browser-local storage on the same device and browser. It does not sync automatically across devices.

Does an infected wound always need antibiotics alone?

No. Wound source control and clinical assessment for collections, necrotic tissue, perfusion and systemic illness are important, with antibiotics used as indicated.

References and further study

These sources support the teaching overview; for an individual patient use current protocols and local specialist guidance. CDC surveillance definitions may differ from bedside diagnostic language.

1. Intercollegiate MRCS candidate guidance — Published syllabus and examination guidance.
2. NCBI Bookshelf: Wound Healing Phases — Normal wound biology and maturity.
3. NCBI Bookshelf: Principles of Wound Healing — Cells, collagen and matrix remodelling.
4. NICE NG125: Surgical site infections — Current prevention, diagnosis and treatment recommendations.
5. CDC NHSN surgical site infection surveillance (2026) — Formal depth categories and surveillance definitions.
6. NIH Office of Dietary Supplements: Vitamin C — Collagen and ascorbic acid.
7. Review: Keloid and hypertrophic scar distinctions — Scar boundaries and pathobiology.

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Thoracic Pelvic Visceral Anatomy

Previous lesson: Article 15 — Thoracic, Pelvic and Visceral Anatomy

Next planned: Article 17 — Surgical Pharmacology and Microbiology. Its link will be added after publication; no placeholder broken hyperlink is used.

Editorial update: 16 October 2026. FreeMedSite MRCS educational material; not patient-specific medical advice.