Wound Healing, Tissue Repair and Scar

CHAPTER 32

MULTIPLE CHOICE QUESTIONS WOUND HEALING

1. Wound healing is affected by: a. Age b. Nutrition c. Dryness or wetness of wound d. Drugs e. Temperature

11. Primary closure of incised wounds must be done within: (Kerala 87) a. 2 hours b. 4 hours c. 6 hours d. 12 hours e. 16 hours



12. The tensile strength of wound reaches that of normal tissue by: (PGI 88) a. 6 weeks b. 2 months e.None c. 4 months d. 6 months



13. Following are required for wound healing except: (All India 93) a. Zinc b. Copper e.None c. Vitamin C d. Calcium



14. Patient has lacerated untidy wound of the leg and attended the casualty after 2 hours. His wound should be: (AIIMS 84) a. Sutured immediately b. Debrided and sutured immediately c. Debrided and sutured secondarily d. Cleaned and dressed



15. When is the maximum collagen content of wound tissue? (PGI 81, Rohtak 87) a. Between 3rd to 5th day b. Between 6th to 17th day c. Between 17th to 21st day d. None of the above



16. A patient with grossly contaminated wound presents 12 hours after an accident, his wound should be managed by: a. Thorough cleaning and primary repair (UPSC 96) b. Thorough cleaning with debridement of all dead and devitalized tissue without primary closure c. Primary closure over a drain d. Covering the defect with split skin graft after cleaning



17. Delayed wound healing is seen in all except: (APPG 96) a. Malignancy b. Hypertension c. Diabetes d. Infection

(PGI Dec 2007)



2. Prevention of wound infection is done by: (PGI June 2005) a. Pre-op shaving b. Pre-op antibiotic therapy c. Monofilament suture d. Wound apposition



3. True about wound healing: (PGI June 2009) a. Infected wound heal by primary intention b. Deep dermal wound heal by scar formation c. Wound contraction is found in healing by secondary intention d. More intense inflammatory response in primary intention





4. True about chronic wound: (PGI Nov 2009) a. Found in DM b. Always require surgical treatment c. May be associated with vascular compromise d. Monofilament sutures prevent infection e. Any wound that does not heal within 3 month



5. Cell not involved in healing of clean wound: a. Macrophages (PGI Nov 2011) b. Platelet c. Fibroblasts d. Polymorphonuclear leukocytes e. Myofibroblasts



6. Management of an open wound seen 12 hours after the injury: (DPG 2011) a. Suturing b. Debridement and suture c. Secondary suturing d. Heal by granulation



7. The vitamin which has inhibitory effect on wound healing is: (MAHE 2005) a. Vitamin A b. Vitamin E c. Vitamin C d. Vitamin B-complex





8. The tensile strength of the wound starts and increases after: (WBPG 2012, MAHE 2005) a. Immediate suture of the wound b. 3–4 days c. 7–10 days d. 6 months

18. In the healing of clean wound the maximum immediate strength of the wound is reached by: a. 2–3 days b. 4–7 days c. 10–12 days d. 13–18 days



19. A clean incised wound heals by: (DPG 92) a. Primary intention b. Secondary intention c. Excessive scaring d. None of the above



20. Which one of the following surgical procedures is considered to a have a clean-contaminated wound? a. Elective open cholecystectomy for cholelithiasis b. Herniorrhaphy with mesh repair c. Lumpectomy with axillary node dissection d. Appendectomy with walled off abscess



21. Fibroblasts in healing wound are derived from: (UPSC 2008, PGI 98) a. Local mesechyme b. Epithelium c. Endothelium d. Vascular fibrosis





9. In a sutured surgical wound, the process of epithelialization is completed within: (UPSC 2007) a. 24 hours b. 48 hours c. 72 hours d. 96 hours 10. Factors that may adversely affect the healing of wounds include all the following except: a. Exposure to UV light b. Exposure to radiation c. Obstructive jaundice d. Advanced neoplasia

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802  Surgery Essence

22. Tensile strength of wound becomes normal after: a. 6 weeks (Recent Questions 2013) b. Never c. 4 months d. 6 months



31. The following statement about keloid is true: a. They do not extend into normal skin b. Local recurrence is common after excision c. They often undergo malignant change d. They are more common in whites than in blacks



32. The worst position for scars is: a. Back b. Shoulder c. Sternum d. Abdomen



33. Keloid fornation is not seen over: a. Ear b. Face c. Eyelids d. Neck

KELOID AND HYPERTROPHIC SCAR

Section 6: Plastic Surgery



23. True statement(s) regarding hypertrophic scar: a. Grow beyond wound margin (PGI Dec 2008) b. More common in female c. Not familial d. Rarely subsides e. Not race related 24. All are true about keloid except: a. Grows beyond would margin b. Excess collagen deposition c. Precancerous leading to cancer d. More common in female e. Whites are at high risk

(PGI Dec 2007)



25. Most common site of hypertrophic keloid is: (AIIMS Nov 93) a. Face b. Leg c. Presternal area d. Arm



26. First line treatment for keloid is: a. Intralesional injection of keloid b. Local steroid c. Radiotherapy d. Wide excision





28. Keloid scar is made up: a. Dense collagen c. Granulamatous tissue



29. What is true about keloids? a. It appears immediately after surgery b. It appears a few days after surgery c. It is limited in its distribution d. It is common in old people



34. The best scars are seen in: a. Infants c. Adults



35. If suture marks are to be avoided, skin sutures should be removed by: (JIPMER 81, AMC 89) a. 72 hours b. 1 week c. 2 weeks d. 3 weeks



36. Degloving injury is: a. Surgeon made wound c. Blunt injury e. Abrasive wound



37. In treatment of hand injuries, the greatest priority is: a. Repair of tendons (All India 96) b. Restoration of skin cover c. Repair of nerves d. Repair of blood vessels



38. During the surgical procedure: (AIIMS 83) a. Tendons should be repaired before nerves b. Nerves should be repaired before tendons c. Tendons should not be repaired at the same time d. None is true

b. Loose fibrous tissue d. Loose areolar tissue

b. Children d. Very old people

(Kerala 2000) b. Lacerated wound d. Avulsion injury

39. ‘Lims salvage’ primarily depends on: a. Vascular injury b. Skin cover c. Bone injury d. Nerve injury

(JIPMER 95)

30. Keloid is best treated: (UPSC 95, 2001) a. Intralesional injection of trimacinolone b. Wide excision and grafting c. Wide excision and suturing d. Deep X-ray therapy

(PGI 88)



(AIIMS Dec 94)

(AIIMS June 95) b. Triamcinolone d. Hydrocortisone

(DNB 2004, 2001)

MISCELLANEOUS

27. Drug used for intralesional injection of keloid is:

a. Prednisolone c. Androgen

(PGI 88)

(AIIMS 97)

40. In an open injury during toileting and debridement, muscle viability is detected by: (PGI June 2003) a. Colour of the muscle b. Muscle size c. Muscle function d. Muscle contractility e. Punctate bleeding spots on cut edge

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Wound Healing, Tissue Repair and Scar  803

EXPLANATIONS WOUND HEALING

1. Ans. a. Age, b. Nutrition, d. Drugs, e. Temperature (Ref: Sabiston 19/e p151-164; Schwartz 10/e p241-268, 9/e p219; Bailey 26/e p24, 25/e p24; Robbins 8/e p106) Factors that inhibit Wound Healing Local Factors

Systemic Factors



• Diabetes mellitusQ • Ionizing radiationQ, temperatureQ • Advanced ageQ, MalnutritionQ • Vitamin C and A deficiencyQ • Mineral (Zinc and IronQ) deficiencies • Drugs (SteroidsQ, Doxorubicin) • JaundiceQ, UremiaQ, MalignancyQ

2. Ans. b. Pre-op antibiotic therapy, c. Monofilament suture, d. Wound apposition (Ref: Bailey 26/e p62, 25/e p42) • Bailey says “Preoperative shaving should be avoided except for aesthetic reasons or to prevent adherence of dressingsQ. If it is to be undertaken, it should be undertaken immediately before surgery as the SSI rate after clean wound surgery may be doubled if it is performed the night before, because minor skin injury enhances superficial bacterial colonizationQ. Cream depilation is messy and hair clipping is best, with the lowest rate of infectionQ.” Avoiding Surgical Site Infections • • • • • • • • • •



Staff should always wash their hands between patientsQ Length of patient stay should be kept to a minimumQ Preoperative shaving should be avoided if possibleQ Antiseptic skin preparationQ should be standardized Bowel preparation for intra-abdominal surgeriesQ Pre-operative antibiotics given IV at the time of inductionQ Attention to theatre technique and discipline Avoid hypothermia perioperatively and ensure supplemental oxygenation in recoveryQ Monofilament sutures are used over polyfilament sutures to prevent infectionQ Proper apposition of the wound and prevention of any dead space and hematomaQ

3. Ans. b. Deep dermal wound heal by scar formation, c. Wound contraction is found in healing by secondary intention: (Ref: Sabiston 19/e p151-164; Schwartz 10/e p234, 1820, 9/e p210-214; Bailey 26/e p24-25, 25/e p24-25; Robbins 8/e p102-106)

Cutaneous Wound Healing • Epidermal appendages do not regenerateQ • There remains a connective tissue scar in place of the mechanically efficient meshwork of collagen in the unwounded dermis. • Very superficial wounds: Little scar formationQ. • In marked contrast with wound healing in adults, fetal cutaneous wounds heal without scar formationQ, up to mid-gestation age in some animals. These wounds show little inflammation and practically no fibrosisQ. Cutaneous wound healing is divided into three phases • Inflammation (early and late) • Granulation tissue formation and re-epithelialization • Wound contraction, ECM deposition and remodeling

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Section 6: Plastic Surgery

• InfectionQ • IschemiaQ • Foreign bodyQ • HematomaQ • Movement • Mechanical stress • Necrotic tissue

804  Surgery Essence Wound Healing By First Intention

By Second Intention

• When wound is sutured primarily with clips, sutures or adhesive materials, the wound healing occurs with minimal scarring, known as healing by first intentionQ • Occurs in Clean and uninfected woundsQ



• When there is extensive loss of cells and tissues and infection is presnt, primary suturing is not possible, wound heals with more scar tissue, known as healing by second intentionQ • More intense inflammatory reactionQ • Much larger amounts of granulation tissue are formedQ • Takes longer time to heal • Wound contraction is presentQ

4. Ans. a. Found in DM, c. May be associated with vascular compromise, d. Monofilament sutures prevent infection, e. Any wound that does not heal within 3 month: (Ref: Bailey 26/e p28, 25/e p28)

Chronic Wound • Wounds that do not heal within 3 months are often considered chronic. • Surgical treatment is only indicated if non-operative treatment has failed or if the patient suffers from intractable painQ

Section 6: Plastic Surgery

Q



5. Ans. b. Platelet, e. Myofibroblasts: (Ref: Sabiston 19/e p151-164; Schwartz 10/e p234,1820, 9/e p210-214; Bailey 26/e p24-25, 25/e p24-25; Robbins 8/e p102-106)

Cutaneous Wound Healing • Wound contraction: Most clearly differentiates primary from secondary healingQ • Permanent wound contraction requires the action of myofibroblasts, altered fibroblasts that have the ultrastructural characteristics of smooth muscle cellsQ. • Contraction of these cells at the wound site decreases the gap between the dermal edges of the wound.

Healing by First Intention (wounds with opposed edges) • Healing of a clean, uninfected surgical incision approximated by surgical sutures is referred as primary union or healing by first intentionQ. • Narrow incisional space immediately fills with clotted blood containing fibrin and blood cells; dehydration of the surface clot forms the well-known scab that covers the wound. • Within 24 hours, neutrophils appear at the margins of the incision, moving toward the fibrin clot. • In 24–48 hours, spurs of epithelial cells move from the wound edgesQ along the cut margins of the dermis, depositing basement membrane components as they move. • By day 3, the neutrophils have been largely replaced by macrophagesQ. Granulation tissue progressively invades the incision space. • By day 5, the incisional space is filled with granulation tissueQ. Neovascularization is maximal • During the second week, there is continued accumulation of collagen and proliferation of fibroblastsQ. The leukocytic infiltrate, edema, and increased vascularity have largely disappeared. • By the end of the first month, the scar is made up of a cellular connective tissue devoid of inflammatory infiltrate, covered now by intact epidermisQ.

6. Ans. b. Debridement and suture (Ref: Sabiston 19/e p245; Schwartz 10/e p234,1820, 9/e p219; Bailey 25/e p25-27; Robbins 8/e p102) • If the blood supply to the wound is adequate and bacterial invasion is absent, wound can be safely closed anytime following proper debridement and irrigationQ. • If there is established infection and tissue is of doubtful viability has been left in-situ, then the wound is left open and re-explored after 48 hoursQ. • If there is infection, and the doubtful viable tissue is now healthy, the deep tissues can be repaired and the wound is closedQ. • If however there is further necrosis and infection, the wound is again debrided and left openQ.



7. Ans. b. Vitamin-E

8. Ans. b. 3–4 days

10. Ans. a. Exposure to UV light http://vip.persianss.ir/

9. Ans. b. 48 hours

Wound Healing, Tissue Repair and Scar  805

11. Ans. c. 6 hours (Ref: Sabiston 19/e p245; Schwartz 9/e p219; Bailey 26/e p25-27, 25/e p25-27; Robbins 8/e p102-104)

Wounds can be closed by • Primary suture: −− Clean woundsQ −− Selected contaminated wounds after thorough wound toileting and debridementQ • Delayed primary suture: −− Heavily contaminated woundsQ −− Wounds in which wound toileting has been delayed for 6–8 hoursQ • Left open to heal by secondary closure

12. Ans. None: (Ref: Sabiston 19/e p163-164; Schwartz 9/e p214; Bailey 25/e p24; Robbins 8/e p105-106) The tensile strength of wound never equals that of unwounded skin.

Wound Strength • At the end of the 1st week, wound strength is approximately 10% of that unwounded skinQ. • Strength increases rapidly over the next 4 weeksQ.

• The recovery of tensile strength results from the excess of collagen synthesis over collagen degradation during the first two months of healing and later from structural modification of collagen fibresQ (cross linking, increased fiber size) after collagen synthesis ceases.

13. Ans. None

14. Ans. b. Debrided and sutured immediately



15. Ans. c. Between 17th - 21st day • Over the first three weeks, strength and collagen content both increases but after 21 days collagen content remain static and only wound strength increasesQ.



16. Ans. b. Thorough cleaning with debridement of all dead and devitalized tissue without primary closure



17. Ans. b. Hypertension



20. Ans. a. Elective open cholecystectomy for cholelithiasis



22. Ans. b. Never

18. Ans. d. 13–18 days

19. Ans. a. Primary intention 21. Ans. a. Local mesechyme

KELOID AND HYPERTROPHIC SCAR

23. Ans. c. Not familial, e. Not race related (Ref: Sabiston 19/e p164-165; Schwartz 10/e p261-263, 9/e p225-227; Bailey 26/e p30, 25/e p30-31; Robbins 8/e p106-107) Feature

Hypertrophic scar

Keloid

Genetic

Not familialQ

May be familialQ

Race

Not race relatedQ

BlackQ >white

Sex

Female =male

FemaleQ >male

Age

ChildrenQ

10–30 yearsQ

Border

Remains within woundQ

Outgrows wound area

Natural History

Subsides with time

Rarely subsides

Site

Flexor surfacesQ

Sternum (MCQ), shoulder, face

Etiology

Related to tensionQ

Unknown

Develop

Within 4 weeks

3 months to year after trauma

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Section 6: Plastic Surgery

• This rate of increase then slows at approximately the third month after the original incision, and reaches a plateau at about 70–80% of the tensile strengthQ of unwounded skin, a condition that may persist for life.

806  Surgery Essence

24. Ans. c. Precancerous leading to cancer, e. Whites are at high risk (Ref: Sabiston 19/e p164-165; Schwartz 10/e p261-263, 9/e p225-227; Bailey 26/e p30, 25/e p30-31; Robbins 8/e p106-107)

Keloids • • • •

Keloids: Scars that grow beyond the borders of the original wounds, and rarely regress with time. More prevalent in blacksQ Keloids appear to have a genetic predispositionQ. Keloid scars tend to occur above the clavicles, on the trunk, on the upper extremities, and on the face. • Keloids have thicker, more abundant collagen bundles that form acellular node like structures in the deep dermal portion of the keloid lesionQ. • Often refractory to medical and surgical interventionQ.



25. Ans. c. Presternal area

26. Ans. a. Intralesional injection of keloid (Ref: Bailey 26/e p30, 25/e p30)

Section 6: Plastic Surgery

Treatment of Hypertrophic and Keloid Scars • • • • • •

Pressure: local moulds or elasticated garmentsQ • Silicone gel sheeting Intralesional steroid injection (triamcinoloneQ) • Excision and steroid injectionQ Excision and postoperative radiationQ (external beam or brachytherapy) Intralesional excision (keloids onlyQ) Laser: To reduce redness (which may resolve in any event) • (All excisions have high rates of recurrenceQ) Vitamin E or palm oil massage (unproven)



27. Ans. b. Triamcinolone



30. Ans. a. Intralesional injection of triamcinolone

28. Ans. a. Dense collagen



32. Ans. c. Sternum

29.

Ans. b. It appears a few days after surgery

31.

Ans. b. Local recurrence is common after excision

33. Ans. c. Eyelids

MISCELLANEOUS

34. Ans. d. Very old people



35. Ans. b. 1 week (Ref: Bailey 26/e p31, 25/e p31) • • • • •



Suture marks may be minimised by using monofilament sutures that are removed early (3–5 days)Q. Sutures inserted under tension will leave marksQ. The wound can be strengthened post suture removal by the use of sticky strips. Fine sutures (6/0 or smaller) placed close to the wound margins tend to leave less scarringQ. Subcuticular suturing avoids suture marks either side of the wound or incisionQ.

36. Ans. d. Avulsion injury (Ref: Bailey 26/e p27, 25/e p27) • Degloving occurs when the skin and subcutaneous fat are stripped by avulsion from its underlying fascia, leaving neurovascular structures, tendon or bone exposedQ.



37. Ans. d. Repair of blood vessels 38. Ans. a. Tendons should be repaired before nerves (Ref: Master Techniques in Orthopedic Surgery Series by Moran and Cooney (2008)/487)

Sequence of repair in Hand Injuries (BE FAN of VeinS) • Bone shortening and stabilization/fixationQ • Arterial anastomosesQ • Skin/wound closureQ

• •

Extensor tendon repairQ Nerve repairQ

• •

Flexor tendon repairQ Venous anastomosisQ

39. Ans. a. Vascular injury 40. Ans. a. Colour of the muscle, d. Muscle contractility, e. Punctate bleeding spots on cut edge (Ref: Bailey 25/e p354-356)

Muscle Viability is detected by ‘4C’ • • • •

ColourQ: Dead muscle has dark unhealthy colour, has lost its sheen ContractilityQ: Dead muscles do not twitch when held by forceps. ConsistencyQ: Dead muscle has lost its turgor and is mushy in consistency Capillary bleedingQ: Dead muscle does not bleed at cut ends. http://vip.persianss.ir/