Dupuytren's disease, congenital hand and miscellaneous

Question 1

What is the surgical dissection sequence encountered when repairing a suspected Stener lesion of the thumb MCP joint?

Answer 1

Skin → Sagittal bands → Adductor aponeurosis → Ulnar collateral ligament → Volar plate.

This sequence enables identification and management of the displaced ulnar collateral ligament, classically prevented from reattachment due to interposition of the adductor aponeurosis, characteristic of a Stener lesion.

Question 2

In a suspected Stener lesion, which structure is typically interposed, preventing healing of the ulnar collateral ligament?

Answer 2

The adductor aponeurosis is interposed, preventing spontaneous healing of the ligament and necessitating surgical intervention.

Question 3

Why must the sagittal bands and adductor aponeurosis be carefully managed during surgical repair of a Stener lesion?

Answer 3

Sagittal bands stabilize the extensor pollicis longus tendon, while the adductor aponeurosis must be divided carefully to reveal the underlying displaced ulnar collateral ligament, facilitating accurate repair and ligament reattachment.

Question 4

What is the recommended age range for pollicisation in patients with Type IIIb hypoplastic thumb (pouce flottant)?

Answer 4

Between 6 months and 3 years of age.

This timing balances anesthesia safety, ease of technical procedure, and optimal cortical plasticity for thumb-index finger reassignment.

Question 5

Why is pollicisation generally avoided in the first few months of life for hypoplastic thumb management?

Answer 5

Early pollicisation (under 3 months) has increased anesthetic risk due to potential incomplete cardiac and pulmonary development, and technical difficulty due to tiny anatomical structures.

Question 6

Which Blauth classification type of thumb hypoplasia is described as a small, vestigial thumb held by a thin stalk of soft tissue (“pouce flottant”)?

Answer 6

Blauth Type IV thumb, requiring excision followed by pollicisation to restore hand function effectively.

Question 7

What is the optimal surgical sequence for replantation of multiple digits amputated at the same anatomical level?

Answer 7

“Part by part” sequence: Bone → Flexor tendon → Extensor tendon → Nerves → Arteries → Veins.

This sequence ensures maximum efficiency and protects delicate vascular and neural structures from potential intraoperative damage.

Question 8

Why is digit-by-digit replantation generally not recommended when multiple digits are amputated at the same level?

Answer 8

Digit-by-digit replantation is less efficient because completing each structure sequentially across all digits reduces overall ischemia time and enhances the viability of replanted digits.

Question 9

During multiple digit replantation, why are arterial repairs completed before venous repairs?

Answer 9

Arterial repair precedes venous repair because restoring arterial inflow first allows identification of optimal veins through venous filling, aiding successful venous anastomosis and tissue reperfusion.

Question 10

What is the appropriate management step upon discovering “rice bodies” and granulomas around flexor tendons during hand surgery?

Answer 10

Perform acid-fast cultures of the tenosynovium and urgently consult microbiology, as these findings suggest tuberculous tenosynovitis, typically from Mycobacterium marinum.

Question 11

What is the most common causative organism of tuberculous tenosynovitis in the hand?

Answer 11

Mycobacterium marinum, typically causing chronic tenosynovitis presenting with “rice bodies” and granulomas.

Question 12

Why is immediate histology insufficient in diagnosing tuberculous tenosynovitis?

Answer 12

Histology alone usually reveals non-specific tenosynovitis, thus requiring microbiological confirmation via acid-fast bacilli cultures to establish diagnosis.

Question 13

What is the initial recommended treatment step for a high-flow arteriovenous malformation (AVM) in the hand?

Answer 13

Highly selective intralesional embolization of the predominant artery (radial artery), reducing lesion size and facilitating safer subsequent surgical resection.

Question 14

Why is ligation alone ineffective for treatment of high-flow AVMs in the hand?

Answer 14

Ligation causes collateral vascular channels to rapidly form, resulting in recurrence. Selective embolization aims to eradicate the nidus, preventing recurrence and facilitating effective surgical resection.

Question 15

Why is sclerotherapy typically ineffective in managing high-flow AVMs?

Answer 15

Sclerotherapy is more effective for low-flow venous malformations. High-flow AVMs require selective embolization, which targets the lesion’s arterial supply more effectively.

Question 16

What is the appropriate treatment for a hypertrophic scar after excision of ulnar-sided polydactyly in a 3-month-old infant?

Answer 16

Scar massage and observation, reassuring caregivers as hypertrophic scars typically improve spontaneously without intervention.

Question 17

Why are intralesional steroid injections contraindicated in managing hypertrophic scars in young infants?

Answer 17

Intralesional steroids are inappropriate in young infants due to potential complications and because hypertrophic scars generally resolve spontaneously.

Question 18

How can hypertrophic scars be clinically differentiated from keloids in pediatric patients?

Answer 18

Hypertrophic scars remain confined to the original wound margins, while keloids overgrow the original boundaries, typically appearing months after the initial injury.

Question 19

Which finding is the most significant indication for surgical intervention in Dupuytren’s disease?

Answer 19

Extension deficit at the proximal interphalangeal joint (PIPJ), as PIP joint contractures are prone to permanent deformity, recurrence, and functional impairment if untreated.

Question 20

Why are palmar nodules not typically an indication for surgical intervention in Dupuytren’s disease?

Answer 20

Palmar nodules alone do not usually lead to significant functional impairment, unlike joint contractures, and thus do not justify surgical risks.

Question 21

Why is the presence of an abductor digiti minimi cord significant in Dupuytren’s disease?

Answer 21

An abductor digiti minimi cord involvement can cause significant functional impairment, particularly limiting hand span and grip function, indicating surgical consideration.

Question 22

Following revascularization of severe forearm trauma with prolonged ischemia, what is the immediate surgical priority?

Answer 22

Perform fasciotomies to prevent compartment syndrome from reperfusion injury and subsequent muscle swelling.

Question 23

Why is primary nerve repair not the immediate priority following severe ischemic forearm trauma?

Answer 23

Initial priority is restoring circulation and preventing compartment syndrome. Nerve repairs typically occur later once tissue viability is stabilized.

Question 24

Why is immediate split-thickness skin grafting inappropriate in severe ischemic soft-tissue trauma?

Answer 24

Immediate grafting is inappropriate due to potential ongoing swelling, tissue viability uncertainty, and likely need for subsequent reoperation after compartmental pressure reduction.

Question 25

What is the recommended management for a stable infantile haemangioma on a toddler’s hand?

Answer 25

Observation and reassurance, as most infantile haemangiomas regress spontaneously over time without intervention.

Question 26

Why is oral propranolol not immediately initiated for a small stable infantile haemangioma without functional impairment?

Answer 26

Propranolol carries systemic risks requiring close monitoring; conservative management is preferable for stable lesions without functional issues.

Question 27

How is an infantile haemangioma clinically distinguished from congenital haemangioma?

Answer 27

Infantile haemangiomas are not present at birth, appear in weeks after birth, and exhibit rapid initial growth followed by gradual spontaneous regression.

Question 28

What is the correct approach to managing a tourniquet that has been applied for 2 hours in a polytrauma patient undergoing limb surgery?

Answer 28

The correct approach is to deflate the tourniquet for 20 minutes, reinflate it, and then proceed with repairs. ## Footnote This technique minimizes ischemic injury while maintaining a controlled surgical field. Releasing the tourniquet completely after 2 hours can lead to a surge of toxic metabolites and potential systemic complications, whereas intermittent deflation balances tissue perfusion and controlled blood loss.

Question 29

Why is immediately proceeding with surgical repairs without deflating a tourniquet after prolonged ischemia dangerous?

Answer 29

Keeping the tourniquet inflated beyond safe limits can cause irreversible ischemic damage to muscles and nerves. It also increases the risk of compartment syndrome and metabolic acidosis upon sudden reperfusion due to the release of ischemic byproducts.

Question 30

What are the potential systemic effects of prolonged tourniquet use followed by sudden deflation in a polytrauma patient?

Answer 30

Sudden deflation after prolonged ischemia (>2 hours) can lead to reperfusion syndrome, characterized by hypotension, metabolic acidosis, hyperkalemia, and rhabdomyolysis, potentially leading to cardiac arrhythmias and multi-organ dysfunction. ## Footnote Gradual deflation with intermittent reinflation helps mitigate these effects.

Question 31

What is the most appropriate management for an 11-month-old with a fixed flexion deformity of the thumb IP joint and a palpable firm lump at the A1 pulley?

Answer 31

Observation and follow-up. ## Footnote Pediatric trigger thumb, often associated with Notta’s nodule, typically resolves spontaneously between 1-3 years of age. Surgical release is reserved for persistent cases beyond 3 years.

Question 32

Why is surgical release of the A1 pulley not recommended for infants under 3 years with trigger thumb?

Answer 32

Most cases resolve spontaneously, and early surgery carries risks of neurovascular injury due to volarly placed structures. Intervention is only considered if the condition persists beyond 3 years.

Question 33

How can pediatric trigger thumb be differentiated from congenital camptodactyly?

Answer 33

Trigger thumb is characterized by a fixed flexion deformity at the IP joint with a firm nodule (Notta’s nodule), whereas camptodactyly affects the PIP joint, often due to abnormal lumbrical or superficial flexor insertion.

Question 34

An 11-year-old boy presents with atrial fibrillation and an isolated hypoplastic thumb. What is the most likely diagnosis?

Answer 34

Holt-Oram syndrome. ## Footnote This autosomal dominant disorder is associated with cardiac septal defects, conduction abnormalities, and upper limb malformations, particularly radial longitudinal deficiencies.

Question 35

How does Holt-Oram syndrome differ from TAR (thrombocytopenia-absent radius) syndrome?

Answer 35

Holt-Oram syndrome presents with cardiac conduction abnormalities and radial deficiencies, whereas TAR syndrome is associated with thrombocytopenia and absent radius, typically without major cardiac defects.

Question 36

Why should all children with radial-sided upper limb anomalies undergo early pediatric cardiology evaluation?

Answer 36

Conditions like Holt-Oram syndrome frequently involve cardiac septal defects or conduction abnormalities, which may be asymptomatic initially but can lead to arrhythmias or heart failure later in life.

Question 37

What is the most appropriate wound coverage option for an 8-year-old with a full-thickness volar forearm burn and a 5 cm segmental ulnar nerve defect?

Answer 37

Flap coverage of the wound. ## Footnote The wound is too large for a skin graft, and vascularized tissue coverage is necessary to protect exposed structures and facilitate nerve healing.

Question 38

Why is direct skin grafting not ideal for an exposed ulnar nerve in a burn injury?

Answer 38

Skin grafting directly over an injured nerve can cause tethering and neuroma formation, leading to chronic pain and dysfunction.

Question 39

When is nerve grafting appropriate in pediatric ulnar nerve injuries following burns?

Answer 39

Nerve grafting is considered only if the nerve develops a neuroma in continuity, as immediate nerve repair is challenging due to unpredictable long-term nerve recovery in young children.

Question 40

Which clinical finding is most indicative of compartment syndrome in a patient with a swollen and tense hand after metacarpal fixation?

Answer 40

Severe pain on passive adduction and abduction of the fingers. ## Footnote This suggests intrinsic muscle compartment involvement, as stretching affected compartments exacerbates ischemic pain.

Question 41

Why is reduced sensation on the dorsum of the hand not an early indicator of hand compartment syndrome?

Answer 41

Sensory loss is a late sign, whereas severe pain with passive movement is the most reliable early indicator of impending compartment syndrome.

Question 42

What is the definitive management for suspected hand compartment syndrome?

Answer 42

Urgent fasciotomies to relieve increased compartmental pressure and prevent irreversible muscle necrosis and nerve damage.

Question 43

Which muscle assumes the function of abductor pollicis brevis after pollicization in Blauth IV thumb hypoplasia?

Answer 43

First dorsal interosseous muscle. ## Footnote Following pollicization, this muscle takes over the function of thumb abduction, enhancing prehension and grip.

Question 44

Which anatomical structure is repositioned to function as the extensor pollicis longus after pollicization?

Answer 44

The extensor indicis proprious of the index finger becomes the new EPL to maintain thumb extension.

Question 45

Why is pollicization preferred over prosthetic thumb reconstruction in Blauth IV thumb hypoplasia?

Answer 45

Pollicization provides functional opposition and grip strength using native tissue, whereas prosthetic reconstruction lacks dynamic motor control and sensory feedback.

Question 46

Which congenital hand anomaly requires preoperative hematological evaluation due to its association with systemic syndromes?

Answer 46

Radial longitudinal deficiency. ## Footnote This condition is associated with syndromes such as Holt-Oram, VACTERL, TAR (thrombocytopenia-absent radius), and Fanconi anemia, which may involve life-threatening hematological or cardiac abnormalities.

Question 47

Why is surgery contraindicated in patients with Fanconi anemia or TAR syndrome until hematological abnormalities are addressed?

Answer 47

Fanconi anemia can lead to pancytopenia and marrow failure, while TAR syndrome involves neonatal thrombocytopenia, making surgical intervention risky due to bleeding complications.

Question 48

What other systemic conditions should be assessed in a patient with radial longitudinal deficiency before surgical correction?

Answer 48

Cardiac anomalies (Holt-Oram syndrome), vertebral and renal abnormalities (VACTERL), and thrombocytopenia (TAR syndrome). These can significantly impact perioperative management.

Question 49

What is the most definitive surgical procedure for a 50-year-old with severe Dupuytren’s contracture and high recurrence risk?

Answer 49

Dermofasciectomy. ## Footnote In high-risk patients (Caucasian males, bilateral disease, younger onset, family history), this procedure removes the affected fascia and replaces it with a skin graft, reducing recurrence.

Question 50

Why is needle aponeurotomy not ideal for high-risk Dupuytren’s disease cases?

Answer 50

While minimally invasive, needle aponeurotomy has a high recurrence rate, making it unsuitable for patients with aggressive, extensive disease.

Question 51

What key prognostic indicators suggest higher recurrence risk in Dupuytren’s disease?

Answer 51

Early onset (<50 years), bilateral involvement, strong family history, ectopic fibromatosis (e.g., Garrod’s pads), and male gender. These factors predict a more aggressive disease course.

Question 52

Which anatomical structure is primarily responsible for distal interphalangeal (DIP) joint contractures in Dupuytren’s disease?

Answer 52

Retrovascular cord. ## Footnote This cord originates from the periosteum of the proximal phalanx and inserts on the lateral aspect of the distal phalanx, leading to DIP joint contractures.

Question 53

How does the retrovascular cord differ from the central cord in Dupuytren’s disease?

Answer 53

The central cord contributes to MCP and PIP contractures, while the retrovascular cord is responsible for DIP contractures by tethering the distal phalanx.

Question 54

What is the appropriate surgical approach for a DIP joint contracture due to a retrovascular cord?

Answer 54

Selective cord excision. ## Footnote This involves removing the pathological cord to restore DIP joint extension.

Question 55

Which clinical feature is most indicative of complex regional pain syndrome (CRPS)?

Answer 55

Sweating asymmetry between the two hands. ## Footnote This is part of the Budapest criteria, which includes sensory, vasomotor, sudomotor/edema, and motor/trophic changes.

Question 56

What is the difference between CRPS type I and type II?

Answer 56

• CRPS Type I (Reflex Sympathetic Dystrophy): No identifiable nerve injury. • CRPS Type II (Causalgia): Clear peripheral nerve injury.

Question 57

What is the first-line treatment approach for early-stage CRPS?

Answer 57

Multimodal therapy, including graded physical therapy, pain control (NSAIDs, neuropathic agents), and desensitization techniques. Early intervention prevents chronic pain progression.

Question 58

What is the best reconstructive option for large exposed tendons after excision of a major burn with no available free flap donor sites?

Answer 58

Dermal regeneration template. ## Footnote This provides a biodegradable matrix for vascularization and requires a secondary skin graft for full coverage.

Question 59

Why is skin allograft not a viable long-term solution in severe burns?

Answer 59

Allografts are temporary and will be rejected within weeks due to the host immune response.

Question 60

Why are tissue expansion and regional pedicled flaps not suitable in this case?

Answer 60

• Tissue expansion is ineffective due to reduced skin elasticity after severe burns. • Regional pedicled flaps are not available as adjacent tissues are also burned.

Question 61

Which racial group has the highest incidence of subungual melanoma?

Answer 61

Darker-skinned populations (African, Asian). ## Footnote Subungual melanoma is a type of acral lentiginous melanoma, which is more common in non-Caucasian groups.

Question 62

What clinical sign is pathognomonic for subungual melanoma?

Answer 62

Hutchinson’s sign – Pigmentation extending to the eponychium or lateral nail folds.

Question 63

What is the standard surgical management for confirmed subungual melanoma?

Answer 63

Wide excision with ≥1 cm margins and sentinel lymph node biopsy. ## Footnote Amputation at the interphalangeal joint may be necessary due to periosteal proximity.

Question 64

What is the most effective pharmacological treatment for adrenaline-induced digital ischemia?

Answer 64

Phentolamine injection. ## Footnote As an alpha-adrenergic blocker, phentolamine reverses vasoconstriction within 1–1.5 hours.

Question 65

Why is hyaluronidase injection not useful in treating epinephrine-induced vasoconstriction?

Answer 65

Hyaluronidase disperses anesthetic agents but does not counteract vasospasm.

Question 66

When should surgical exploration and revascularization be considered for digital ischemia?

Answer 66

Only if ischemia persists despite pharmacologic reversal, as digits are highly tolerant of transient ischemia.

Question 67

Which tumor presents with intermittent sharp pain, cold intolerance, and pinpoint tenderness under the nail matrix?

Answer 67

Glomus tumor. ## Footnote Classic signs include “Love Sign” (focal pressure pain) and Hildreth’s Sign (pain relief with tourniquet application).

Question 68

What is the best imaging modality for diagnosing a glomus tumor?

Answer 68

MRI – Clearly delineates the tumor and guides surgical excision.

Question 69

How does subungual melanoma differ clinically from a glomus tumor?

Answer 69

Subungual melanoma presents with progressive dark streaking (Hutchinson’s sign) and lacks paroxysmal pain seen in glomus tumors.

Question 70

What is the best initial management for a non-healing ulcer with a violaceous border in a patient with ulcerative colitis?

Answer 70

Referral to dermatology for medical treatment. ## Footnote Pyoderma gangrenosum is an autoimmune neutrophilic dermatosis, requiring steroids or immunomodulators.

Question 71

Why is debridement contraindicated in pyoderma gangrenosum?

Answer 71

Surgical trauma exacerbates the ulcer, leading to pathergy (worsening ulceration).

Question 72

What systemic conditions are associated with pyoderma gangrenosum?

Answer 72

Inflammatory bowel disease (IBD), rheumatoid arthritis, and hematologic malignancies.

Question 73

What is the most common cause of contracture at the proximal interphalangeal joint in Dupuytren’s disease?

Answer 73

Central cord

Question 74

Which pathological structure arises from the periosteum of the proximal phalanx and causes distal interphalangeal joint contracture in Dupuytren’s disease?

Answer 74

Retrovascular cord

Question 75

Which anatomical structure contributes to the formation of Dupuytren’s disease by involving the lateral digital sheath?

Answer 75

Spiral cord

Question 76

Which structure in Dupuytren’s disease is vertical and sometimes involved in disease progression?

Answer 76

Septa of Legueu and Juvara

Question 77

Which pathological structure causes contractures of the proximal interphalangeal joint of the little finger in Dupuytren’s disease?

Answer 77

Abductor digiti minimi cord

Question 78

Which consumptive coagulopathy is life-threatening and associated with large vascular anomalies?

Answer 78

Kassabach-Merritt syndrome

Question 79

Which condition is an angiosarcoma that can develop after years of chronic lymphoedema?

Answer 79

Stewart-Treves syndrome

Question 80

Which painful neuritis can result in paralysis of upper limb muscles?

Answer 80

Parsonage-Turner syndrome

Question 81

Which syndrome has symptoms that can be confused with carpal tunnel syndrome?

Answer 81

Hand Arm Vibration Syndrome

Question 82

Which syndrome can result in a loss of function in patients with rheumatoid arthritis?

Answer 82

Vaughn-Jackson Syndrome

Question 83

Which sign is elicited by exsanguinating the digit and applying a tourniquet, resulting in pain relief of a glomus tumour?

Answer 83

Hildreth’s sign

Question 84

Which sign is used to differentiate a pre-ganglionic from a post-ganglionic brachial plexus injury?

Answer 84

Froment’s sign

Question 85

Which sign indicates a poor prognosis in a ring avulsion injury?

Answer 85

Red streak sign

Question 86

Which sign is a result of dysfunction of the third palmar interosseous?

Answer 86

Wartenberg’s sign

Question 87

Which sign can be a prodrome to Vaughn-Jackson Syndrome?

Answer 87

Piano key sign

Question 88

What is one of the recognised procedures to deal with a duplicate thumb?

Answer 88

Bilhaut-Cloquet procedure

Question 89

Which congenital hand difference requires ruling out cardiac and haematological conditions?

Answer 89

Radial longitudinal deficiency

Question 90

Which condition corresponds to a neurological pattern, most often in the median nerve or its branches?

Answer 90

Macrodactyly

Question 91

What condition is associated with a delta phalanx seen on radiographs?

Answer 91

Clinodactyly

Question 92

Which congenital hand condition can cause acrosyndactyly with fenestrations between two digits?

Answer 92

Constriction Band Syndrome

Question 93

Which agent is used to treat lidocaine toxicity from an overdose?

Answer 93

20% lipid emulsion

Question 94

Which local anaesthetic is a class IB anti-arrhythmic and can be used to treat ventricular arrhythmias?

Answer 94

Lidocaine hydrochloride

Question 95

Which agent, along with lidocaine, makes up the constituents of the topical EMLA cream?

Answer 95

Tetracaine

Question 96

Which is an ester class of local anaesthetic and an effective topical anaesthetic?

Answer 96

Prilocaine

Question 97

Which agent can cause precipitation if used in the wrong quantities when combining local anaesthetics?

Answer 97

Sodium bicarbonate

Question 98

What is the most appropriate immediate management for doxorubicin extravasation in a patient on an oncology ward?

Answer 98

The best immediate management is to aspirate the canula, remove it, and start intravenous dexrazoxane. Doxorubicin is a DNA-binding vesicant, and dispersing it with flushing or hyaluronidase can increase tissue necrosis. Dexrazoxane is the most effective antidote, preventing surgery in over 98% of cases.

Question 99

Why is hyaluronidase contraindicated in anthracycline extravasation injuries?

Answer 99

Hyaluronidase is generally used to dilute and disperse extravasated agents, but in anthracycline extravasation (e.g., doxorubicin), dispersing the drug can lead to a larger area of necrosis. DNA-binding vesicants like doxorubicin should be localized and neutralized, making intravenous dexrazoxane the preferred treatment.

Question 100

When should surgical debridement and skin grafting be considered for anthracycline extravasation injuries?

Answer 100

Surgical debridement and grafting should only be considered if necrosis has already developed and conservative measures, including dexrazoxane administration, have failed. Early intervention with dexrazoxane significantly reduces the need for surgery and allows continued chemotherapy without interruption.