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ABPS Surgery of the Hand study materials
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ABPS Surgery of the Hand practice questions

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Question 1Congenital and Pediatric Hand Conditions

A 15-month-old child has a thumb interphalangeal joint that has been locked in flexion since 6 months of age. There is no passive extension. What is the most appropriate initial management?

  1. Observation with passive stretching Correct answer.
  2. Superficialis-to-profundus tendon transfer
  3. Corticosteroid injection into the flexor sheath
  4. Open release of the A1 pulley

Explanation

Pediatric trigger thumb is usually treated initially with observation and gentle passive stretching because most cases resolve spontaneously during the first 1–2 years of life. Surgical A1 pulley release is reserved for persistent, functionally limiting deformity after conservative treatment has failed or the child is older.

Question 2Congenital and Pediatric Hand Conditions

A newborn has a small extra digit on the ulnar border of the hand that is attached only by a narrow skin pedicle and contains no bone. How is this anomaly classified?

  1. Postaxial type A
  2. Preaxial type I
  3. Central polydactyly
  4. Postaxial type B Correct answer.

Explanation

Postaxial polydactyly is classified by the degree of development of the extra ulnar digit. Type B is a rudimentary digit attached by a skin pedicle without bone, whereas type A is a well-formed digit that articulates with the hand.

Question 3Congenital and Pediatric Hand Conditions

Which web space is most commonly involved in congenital syndactyly of the hand?

  1. Third web space Correct answer.
  2. Second web space
  3. Fourth web space
  4. First web space

Explanation

Congenital syndactyly most frequently affects the third web space, between the middle and ring fingers. The second web space is the next most common, while first and fourth web space involvement is less frequent.

Question 4Congenital and Pediatric Hand Conditions

Camptodactyly most characteristically produces a flexion deformity at which location?

  1. Distal interphalangeal joint of the index finger
  2. Proximal interphalangeal joint of the ring finger
  3. Proximal interphalangeal joint of the small finger Correct answer.
  4. Metacarpophalangeal joint of the thumb

Explanation

Camptodactyly is a nontraumatic flexion deformity that most often affects the proximal interphalangeal joint of the small finger. It may be present at birth or develop during adolescence and can be bilateral.

Question 5Congenital and Pediatric Hand Conditions

Clinodactyly of the small finger in a child is most commonly caused by which abnormality?

  1. A delta phalanx of the middle phalanx Correct answer.
  2. Premature growth arrest of the distal phalanx
  3. Contracture of the extensor tendon
  4. Malunion of a proximal phalanx fracture

Explanation

Clinodactyly is a radioulnar angulation of a digit, and in the small finger it most often results from a delta phalanx or longitudinal epiphyseal bracket of the middle phalanx. This causes asymmetric growth and progressive angulation.

Question 6Congenital and Pediatric Hand Conditions

Which clinical finding is most characteristic of Poland syndrome?

  1. Bilateral renal agenesis with thumb hypoplasia
  2. Sternal pectoralis major absence with hand hypoplasia Correct answer.
  3. Absent latissimus dorsi with radial clubhand
  4. Craniosynostosis with mitten syndactyly

Explanation

Poland syndrome consists of unilateral absence or hypoplasia of the sternal head of the pectoralis major with ipsilateral symbrachydactyly or hand hypoplasia. It is a sporadic developmental anomaly and does not typically involve the latissimus dorsi or craniosynostosis.

Question 7Congenital and Pediatric Hand Conditions

A newborn presents with several deep constriction rings around the fingers, distal lymphedema, and asymmetric amputations of two fingertips. What is the most likely diagnosis?

  1. Congenital clasped thumb
  2. Amniotic band sequence Correct answer.
  3. Poland syndrome
  4. Symbrachydactyly

Explanation

Amniotic band sequence produces asymmetric constriction rings, distal swelling, and amputations caused by fibrous bands encircling fetal parts. The findings are random and do not follow a dermatomal or vascular distribution.

Question 8Congenital and Pediatric Hand Conditions

A child with thumb hypoplasia has absent thenar muscles, an unstable metacarpophalangeal joint, and no carpometacarpal joint. Which Blauth type does this represent?

  1. Blauth type IIIB Correct answer.
  2. Blauth type IIIA
  3. Blauth type I
  4. Blauth type II

Explanation

Blauth type IIIB is defined by severe thumb hypoplasia with an absent carpometacarpal joint, in addition to absent thenar musculature and MCP instability. Type IIIA has a stable CMC joint, and type IV is a floating thumb with an absent metacarpal.

Question 9Congenital and Pediatric Hand Conditions

Which Wassel type is the most common pattern of thumb duplication?

  1. Wassel type IV Correct answer.
  2. Wassel type III
  3. Wassel type VI
  4. Wassel type II

Explanation

Wassel type IV, duplication of the proximal phalanx, is the most common thumb duplication pattern. The Wassel classification is based on the level of duplication, with type IV accounting for the largest share of cases.

Question 10Congenital and Pediatric Hand Conditions

A child has simple syndactyly between the middle and ring fingers. To allow remodeling and avoid growth disturbance, release is generally recommended at what age?

  1. 12 to 18 months Correct answer.
  2. 3 to 4 years
  3. 6 to 9 months
  4. After 8 years

Explanation

Simple syndactyly of digits with similar length is usually released between 12 and 18 months of age. Earlier release is considered for border digits or digits of unequal length because of the risk of tethering and angular deformity.

Question 11Congenital and Pediatric Hand Conditions

Radial longitudinal deficiency is most commonly associated with which systemic condition?

  1. VACTERL association Correct answer.
  2. Marfan syndrome
  3. Neurofibromatosis type 1
  4. Apert syndrome

Explanation

Radial longitudinal deficiency is most often associated with VACTERL association, which includes vertebral, anal, cardiac, tracheoesophageal, renal, and limb anomalies. Holt-Oram syndrome and thrombocytopenia-absent radius syndrome are other important associations.

Question 12Congenital and Pediatric Hand Conditions

A newborn with a brachial plexus birth injury holds the arm adducted and internally rotated with the elbow extended and the wrist flexed. Which nerve roots are most likely involved?

  1. C4 and C5
  2. C8 and T1
  3. C5 and C6 Correct answer.
  4. C7 and C8

Explanation

The waiter's tip posture reflects an upper trunk injury involving C5 and C6, with weakness of the deltoid, supraspinatus, biceps, and brachialis. Lower trunk injuries (C8-T1) produce a different pattern with intrinsic hand weakness and a clawed posture.

Question 13Congenital and Pediatric Hand Conditions

Which description best characterizes the hand deformity in Apert syndrome?

  1. Complex mitten syndactyly of all digits Correct answer.
  2. Ulnar clubhand with an absent ulnar digit
  3. Transverse deficiency at the wrist
  4. Radial clubhand with an absent thumb

Explanation

Apert syndrome produces complex syndactyly of the index, middle, and ring fingers, often with a mitten or rosebud appearance, and is associated with craniosynostosis. It results from FGFR2 mutations and frequently requires staged release.

Question 14Congenital and Pediatric Hand Conditions

An otherwise healthy infant has bilateral thumbs that are clasped into the palm and cannot be actively extended. What is the most appropriate initial treatment?

  1. Splinting and passive stretching Correct answer.
  2. Immediate pollicization of the index finger
  3. Release of the first dorsal interosseous
  4. Transfer of the flexor pollicis longus

Explanation

Congenital clasped thumb is initially managed with splinting and passive stretching, especially in infants, because many improve as voluntary extension develops. Surgical reconstruction is considered if the deformity persists after a reasonable trial of conservative treatment.

Question 15Congenital and Pediatric Hand Conditions

Which finding is most commonly associated with ulnar longitudinal deficiency?

  1. Dislocation of the radial head Correct answer.
  2. Absent thumb
  3. Radial clubhand
  4. Mitten syndactyly

Explanation

Ulnar longitudinal deficiency often produces ulnar-sided deficiency with bowing of the forearm and dislocation of the radial head. The radial head may be subluxated or dislocated because of the abnormal forearm mechanics and soft tissue tethering.

Question 16Congenital and Pediatric Hand Conditions

In congenital radioulnar synostosis, what is the main indication for surgical treatment?

  1. Any degree of limited forearm rotation
  2. Cosmetic appearance of the forearm
  3. Wrist pain with activity
  4. Fixed pronation that interferes with hand function Correct answer.

Explanation

Surgery is generally reserved for a fixed pronation deformity severe enough to impair activities such as feeding or perineal care. Mild deformity with functional compensation is usually managed without surgery.

Question 17Congenital and Pediatric Hand Conditions

Symphalangism of the hand is best defined as which abnormality?

  1. Overgrowth of a single digit
  2. Absence of the metacarpophalangeal joint
  3. Duplication of the distal phalanx
  4. Failure of PIP joint segmentation Correct answer.

Explanation

Symphalangism is a failure of joint formation, most often at the proximal interphalangeal joint, resulting in a stiff finger without a normal joint space. It may be isolated or associated with syndromes such as Apert syndrome.

Question 18Congenital and Pediatric Hand Conditions

A child has progressive overgrowth of the index and middle fingers with enlarged soft tissue and bone. What is the most appropriate surgical strategy?

  1. Observation until skeletal maturity
  2. Immediate amputation of the affected digits
  3. Staged debulking with epiphysiodesis Correct answer.
  4. Radiation therapy to the growth plates

Explanation

Macrodactyly is managed with staged soft tissue debulking and epiphysiodesis or growth plate arrest to control progressive enlargement. Amputation is reserved for severe, nonfunctional cases, and radiation is not used.

Question 19Congenital and Pediatric Hand Conditions

A child has a Blauth type IV floating thumb with no metacarpal and no functional thumb. What is the preferred reconstructive procedure?

  1. First web space deepening
  2. Index finger pollicization Correct answer.
  3. Opponensplasty
  4. Thenar muscle transfer

Explanation

Blauth type IV thumb has no functional metacarpal and cannot be reconstructed reliably, so pollicization of the index finger is the preferred treatment. It provides a stable, sensate, and functional thumb substitute.

Question 20Congenital and Pediatric Hand Conditions

Which feature best distinguishes amniotic band sequence from symbrachydactyly?

  1. Absence of the thumb
  2. Asymmetric constriction rings and random amputations Correct answer.
  3. Shortening of the middle phalanges
  4. Bilateral involvement of the hands

Explanation

Amniotic band sequence causes asymmetric, randomly distributed constriction rings and amputations because fibrous bands entangle fetal parts. Symbrachydactyly typically produces short digits with absent or hypoplastic middle phalanges in a more consistent pattern without constriction bands.

Question 21Congenital and Pediatric Hand Conditions

A child has clinodactyly caused by a longitudinal epiphyseal bracket of the middle phalanx. What is the most appropriate surgical treatment?

  1. A1 pulley release
  2. Bracket resection with wedge osteotomy Correct answer.
  3. Simple observation until skeletal maturity
  4. PIP joint arthrodesis

Explanation

A longitudinal epiphyseal bracket tethers growth along one side of the phalanx, causing progressive angular deformity. Treatment involves resecting the bracket and performing a corrective osteotomy, often with fat interposition to prevent recurrence.

Question 22Congenital and Pediatric Hand Conditions

Which statement about typical cleft hand (central deficiency) is correct?

  1. It is usually acquired after birth
  2. It is always associated with amniotic bands
  3. Often bilateral with autosomal dominant inheritance Correct answer.
  4. It primarily affects the ulnar border of the hand

Explanation

Typical cleft hand is a congenital central deficiency that is often bilateral and may be inherited in an autosomal dominant pattern, sometimes with cleft feet. It is distinct from symbrachydactyly, which is usually sporadic and not inherited.

Question 23Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

A young adult falls onto an outstretched hand and has point tenderness in the floor of the anatomic snuffbox, but the initial radiographs show no fracture. Which carpal bone is most likely injured?

  1. Triquetrum
  2. Lunate
  3. Trapezium
  4. Scaphoid Correct answer.

Explanation

The scaphoid is the most commonly fractured carpal bone, and snuffbox tenderness after a fall on an outstretched hand is managed as a scaphoid fracture until proven otherwise, with immobilization and repeat imaging. Missed injuries carry a real risk of nonunion and avascular necrosis of the proximal pole.

Question 24Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

A ball strikes the tip of an extended finger. The patient cannot actively extend the distal interphalangeal joint but has full active extension at the proximal interphalangeal joint. Which structure is injured?

  1. Central slip of the extensor tendon
  2. Terminal extensor tendon Correct answer.
  3. Flexor digitorum profundus tendon
  4. Volar plate

Explanation

Loss of active distal interphalangeal extension with preserved proximal interphalangeal extension defines a mallet finger, caused by disruption of the terminal extensor tendon. The tendon is treated with continuous distal interphalangeal extension splinting for six to eight weeks.

Question 25Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

A rugby player catches a jersey with the ring finger, which is forcibly extended at the distal interphalangeal joint while the profundus is contracting. He cannot flex the distal interphalangeal joint. Which structure is avulsed?

  1. Flexor digitorum superficialis tendon
  2. Radial collateral ligament
  3. Flexor digitorum profundus tendon Correct answer.
  4. Central slip of the extensor tendon

Explanation

This is a jersey finger, an avulsion of the flexor digitorum profundus insertion, most common in the ring finger. The finger rests in extension and lacks active distal interphalangeal flexion; early surgical repair gives the best result.

Question 26Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

In a Bennett fracture of the first metacarpal base, which muscle displaces the metacarpal shaft proximally and radially?

  1. Extensor pollicis brevis
  2. Abductor pollicis longus Correct answer.
  3. First dorsal interosseous
  4. Flexor pollicis longus

Explanation

The abductor pollicis longus inserts on the first metacarpal base and retracts the shaft proximally and radially, while the adductor pollicis pulls the small articular fragment into adduction. This deforming force explains why the fracture-subluxation is unstable and usually requires pinning or screw fixation.

Question 27Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

Which direction of dislocation occurs most commonly at the proximal interphalangeal joint?

  1. Radial
  2. Ulnar
  3. Dorsal Correct answer.
  4. Volar

Explanation

Dorsal proximal interphalangeal dislocation is the most common pattern and results from a hyperextension force that ruptures the volar plate, allowing the middle phalanx to displace dorsally. Volar and coronal dislocations are distinctly uncommon.

Question 28Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

Which pattern describes a boxer's fracture?

  1. Fifth metacarpal neck fracture with apex dorsal angulation Correct answer.
  2. Fifth metacarpal base fracture with carpometacarpal subluxation
  3. Transverse fracture through the neck of the fifth metacarpal
  4. Avulsion fracture of the base of the fifth proximal phalanx

Explanation

A boxer's fracture is a fracture of the fifth metacarpal neck, usually from a direct blow with a clenched fist; the head angulates volarly so the fracture apex points dorsally. Rotational malalignment, rather than angulation alone, is the key indication for reduction and fixation.

Question 29Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

A patient has a distal phalanx fracture with a nail bed laceration and a tense subungual hematoma. What is the most appropriate management?

  1. Excision of the entire nail plate and full-thickness skin grafting
  2. Immediate terminal amputation of the distal phalanx through the tuft
  3. Nail bed repair with fine absorbable suture and splinting Correct answer.
  4. Observation with a bulky soft dressing and weekly review

Explanation

A lacerated nail bed should be repaired with fine absorbable suture under magnification, and the associated distal phalanx fracture splinted, to prevent nail deformity and nonunion. The nail plate can be cleaned and replaced as a natural splint over the repair.

Question 30Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

A distal radius fracture in a young adult shows volar angulation of the distal fragment after a fall onto a flexed wrist. Which eponym describes this fracture?

  1. Smith fracture Correct answer.
  2. Chauffeur fracture
  3. Colles fracture
  4. Barton fracture

Explanation

A Smith fracture is a distal radius fracture with volar angulation of the distal fragment, sometimes called a reverse Colles fracture. Colles fractures displace dorsally, Barton fractures are intra-articular with a subluxated rim fragment, and chauffeur fractures involve the radial styloid.

Question 31Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

Why is the proximal pole of the scaphoid especially prone to avascular necrosis after a waist fracture?

  1. The proximal pole is supplied only by the ulnar artery
  2. A branch of the anterior interosseous artery enters the proximal pole
  3. The proximal pole has no capsular attachments
  4. Blood enters distally via the dorsal ridge Correct answer.

Explanation

Most of the scaphoid's intraosseous blood supply enters through the dorsal ridge distal to the waist, so flow to the proximal pole is retrograde. Fractures proximal to this entry point can deprive the proximal fragment of perfusion, leading to nonunion and avascular necrosis.

Question 32Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

A finger is jammed in hyperextension, causing proximal interphalangeal joint pain with a small volar lip avulsion and a congruent joint on radiographs. What is the most appropriate initial treatment?

  1. Immediate open surgical repair of the volar plate
  2. Buddy taping with the finger in full flexion for six weeks
  3. Extension block splinting with early protected motion Correct answer.
  4. Arthrodesis of the proximal interphalangeal joint

Explanation

A stable volar plate injury with a congruent joint is treated with a dorsal extension-block splint and early protected motion, which prevents stiffness while allowing the ligament to heal. Surgery is reserved for large avulsion fragments with subluxation or an irreducible joint.

Question 33Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

A lateral wrist radiograph shows the lunate displaced volarly with a spilled-teacup appearance, while the capitate sits within the lunate fossa of the radius. What is the diagnosis?

  1. Distal radius fracture with dorsal tilt
  2. Perilunate dislocation
  3. Scapholunate dissociation
  4. Lunate dislocation Correct answer.

Explanation

In a lunate dislocation the lunate is extruded volarly out of the lunate fossa while the capitate remains aligned with the radius, producing the spilled-teacup sign. In a perilunate dislocation the lunate stays in the fossa and the capitate dislocates dorsally.

Question 34Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

A patient has ulnar-sided wrist pain after a fall, with tenderness in the soft spot just distal to the ulnar styloid between the flexor carpi ulnaris tendon and the ulna, plus positive ulnar variance. Which structure is most likely injured?

  1. Hook of the hamate
  2. Scapholunate ligament
  3. Extensor pollicis brevis sheath
  4. Triangular fibrocartilage complex Correct answer.

Explanation

The fovea sign localises pathology to the triangular fibrocartilage complex, and positive ulnar variance increases ulnocarpal load and predisposes to degenerative tears. Initial treatment is immobilisation and rehabilitation, with arthroscopic repair or debridement for persistent symptoms.

Question 35Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

Which statement best describes a Stener lesion of the thumb metacarpophalangeal joint?

  1. Adductor aponeurosis interposition prevents healing and requires repair Correct answer.
  2. An avulsion fracture of the ulnar proximal phalanx that heals in a cast
  3. A tear of the radial collateral ligament of the thumb
  4. A rupture of the extensor pollicis longus tendon at Lister's tubercle

Explanation

In a Stener lesion the adductor pollicis aponeurosis becomes interposed between the retracted ulnar collateral ligament and its bony insertion, so spontaneous healing cannot occur. Complete ruptures with clinical instability therefore require surgical repair.

Question 36Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

Which finding most strongly indicates operative treatment of an isolated metacarpal shaft fracture?

  1. Clinically evident rotational deformity with finger scissoring Correct answer.
  2. Ten degrees of apex dorsal angulation on the lateral view
  3. A fracture of the second metacarpal shaft in a labourer
  4. A non-displaced transverse fracture of the fourth metacarpal

Explanation

Rotational malalignment does not remodel and causes the fingers to overlap during flexion, producing a functional deficit that warrants reduction and fixation. Angulation in the plane of motion may be accepted within limits that depend on which ray is involved.

Question 37Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

A closed, non-displaced tuft fracture of the distal phalanx has a small, painful subungual hematoma with an intact nail fold. What is the appropriate treatment?

  1. Nail trephination if painful, with a protective splint Correct answer.
  2. Percutaneous pinning across the metacarpophalangeal joint for six weeks
  3. Immediate amputation of the distal phalanx through the tuft
  4. Open reduction and internal fixation with two K-wires

Explanation

Non-displaced tuft fractures are treated conservatively with a protective splint, and a painful subungual hematoma can be decompressed by trephination. The nail bed is formally repaired only when it is lacerated.

Question 38Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

Which fracture is described as a comminuted intra-articular fracture of the base of the first metacarpal?

  1. Avulsion fracture of the ulnar base of the first metacarpal
  2. Fracture of the waist of the scaphoid
  3. Rolando fracture Correct answer.
  4. Transverse fracture through the neck of the fifth metacarpal

Explanation

The Rolando fracture is a comminuted, often Y- or T-shaped intra-articular fracture of the first metacarpal base, in contrast to the Bennett fracture, which has a single ulnar-sided avulsion fragment. Comminution makes stable fixation difficult and often requires plate or external fixation.

Question 39Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

A cyclist has ulnar palmar wrist pain, weak grip, and point tenderness over the hypothenar eminence, but standard wrist radiographs are normal. What is the most appropriate next step?

  1. Nerve conduction study of the ulnar nerve
  2. Carpal tunnel view or CT scan Correct answer.
  3. Serum inflammatory markers and wrist aspiration
  4. Repeat plain radiographs in six weeks

Explanation

Hook of the hamate fractures are frequently occult on standard posteroanterior and lateral views, so a carpal tunnel view or CT scan is needed to confirm the diagnosis. Untreated fractures can cause ulnar nerve irritation or attritional rupture of the little finger flexor tendons.

Question 40Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

Which clinical finding is the earliest and most reliable indicator of compartment syndrome in an injured hand or forearm?

  1. Loss of two-point discrimination in all digits
  2. Pain on passive finger stretch Correct answer.
  3. Pallor of the fingertips with sluggish capillary refill
  4. Absent radial pulse on handheld Doppler

Explanation

Pain out of proportion to the injury and pain on passive stretch of the involved compartment are the earliest and most dependable signs. Pulselessness, pallor, and neurological deficit are late findings, and definitive treatment is urgent fasciotomy.

Question 41Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

An adult has a midshaft radius fracture with clinical instability of the distal radioulnar joint. What is the most appropriate definitive treatment?

  1. Plate fixation of the radius with DRUJ assessment Correct answer.
  2. Isolated ulnar shortening osteotomy with plating
  3. Closed reduction and cast immobilization for six weeks
  4. Spanning external fixation across the wrist joint

Explanation

This is a Galeazzi fracture-dislocation, which is unstable in adults and has a high failure rate with closed treatment. Anatomic plate fixation of the radius usually reduces the distal radioulnar joint, which is then tested and pinned if it remains unstable.

Question 42Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

A painter sustains a high-pressure injection injury to the index finger from a paint gun. The skin puncture is small and the finger looks nearly normal. What is the correct management?

  1. Incision and drainage in the emergency department
  2. Observation with oral antibiotics and elevation
  3. Urgent debridement with broad-spectrum antibiotics Correct answer.
  4. Delayed exploration after 24 hours of intravenous antibiotics

Explanation

High-pressure injection injuries drive material deep into the tissues and cause extensive chemical and ischaemic necrosis that is poorly reflected by the benign skin findings. They are surgical emergencies requiring urgent formal debridement and broad-spectrum antibiotics, and delay increases the risk of amputation.

Question 43Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

A patient has wrist pain after a fall, and the posteroanterior radiograph shows a gap of more than 3 mm between the scaphoid and lunate with a cortical ring sign of the scaphoid. Which structure is disrupted?

  1. Radioscaphocapitate ligament
  2. Scapholunate interosseous ligament Correct answer.
  3. Lunotriquetral ligament
  4. Dorsal radiocarpal ligament

Explanation

Scapholunate ligament disruption produces a widened scapholunate interval, the Terry Thomas sign, and the scaphoid rotates into flexion giving a cortical ring sign. Untreated, this progresses to a scapholunate advanced collapse pattern of arthritis.

Question 44Hand and Wrist Trauma (Fractures, Dislocations, Soft-Tissue Injury)

A patient has a comminuted radial head fracture, forearm swelling, and tenderness with instability at the distal radioulnar joint. Which injury pattern should be suspected?

  1. Essex-Lopresti injury Correct answer.
  2. Terrible triad of the elbow
  3. Monteggia fracture-dislocation
  4. Galeazzi fracture-dislocation

Explanation

The Essex-Lopresti injury combines a radial head fracture, disruption of the interosseous membrane, and distal radioulnar joint dislocation, allowing the radius to migrate proximally. Recognition is critical because radial head excision in this setting worsens proximal migration and wrist dysfunction.

Question 45Nerve Injury, Compression Neuropathy, and Microsurgery

A patient has numbness over the volar aspect of the hand after a laceration at the wrist. Which territory is supplied by the median nerve?

  1. Dorsal ulnar border of the hand and little finger
  2. Volar little finger and ulnar half of the ring finger
  3. Volar thumb, index, middle, and radial half of the ring finger Correct answer.
  4. Dorsal first web space

Explanation

The median nerve provides palmar cutaneous and digital sensory branches to the thumb, index, middle, and radial half of the ring finger. The ulnar nerve supplies the little finger and ulnar half of the ring finger, while the radial sensory nerve supplies the dorsal first web space. Dorsal ulnar sensation comes from the dorsal cutaneous branch of the ulnar nerve.

Question 46Nerve Injury, Compression Neuropathy, and Microsurgery

Which test for carpal tunnel syndrome is performed by holding the wrists in full flexion for about one minute?

  1. Tinel sign
  2. Phalen test Correct answer.
  3. Froment test
  4. Durkan test

Explanation

The Phalen test reproduces median nerve compression by maximally flexing the wrist and holding it for roughly 30 to 60 seconds. The Durkan test uses direct manual pressure over the carpal tunnel instead. Tinel sign uses percussion, and Froment test assesses ulnar nerve function.

Question 47Nerve Injury, Compression Neuropathy, and Microsurgery

A patient reports tingling in the fingertip when the examiner taps over a repaired digital nerve at the proximal phalanx. This finding most likely indicates which process?

  1. Complex regional pain syndrome is developing
  2. A painful neuroma has formed
  3. Ischemic contracture is present
  4. Regenerating axons are advancing Correct answer.

Explanation

A positive Tinel sign advancing distally reflects regenerating axons becoming mechanosensitive as they grow along the distal stump. Serial Tinel testing is used to track regeneration over time. A static or exquisitely painful Tinel at the repair site may suggest neuroma formation, but distal tingling indicates advancement.

Question 48Nerve Injury, Compression Neuropathy, and Microsurgery

A closed midshaft humeral fracture is most likely to produce which motor deficit?

  1. Wrist drop Correct answer.
  2. Clawing of the ulnar two digits
  3. Thenar atrophy
  4. Loss of finger abduction

Explanation

The radial nerve runs in the spiral groove against the humeral shaft, so midshaft fractures commonly injure it and paralyze the wrist and finger extensors. Wrist drop with preserved elbow flexion is the classic picture. Clawing and weak finger abduction indicate ulnar nerve injury, and thenar atrophy indicates median nerve injury.

Question 49Nerve Injury, Compression Neuropathy, and Microsurgery

Which nerve is most commonly harvested as a donor cable graft for bridging a peripheral nerve defect in the hand?

  1. Sural nerve Correct answer.
  2. Posterior interosseous nerve
  3. Ulnar nerve
  4. Median nerve

Explanation

The sural nerve is the standard donor because it is purely sensory, expendable, and available in sufficient length through a single leg incision. It provides a good match for digital nerve caliber. Harvesting a major hand nerve would create an unacceptable secondary deficit.

Question 50Nerve Injury, Compression Neuropathy, and Microsurgery

Carpal tunnel syndrome is caused by compression of which nerve?

  1. Median nerve Correct answer.
  2. Posterior interosseous nerve
  3. Radial nerve
  4. Ulnar nerve

Explanation

The median nerve passes through the carpal tunnel beneath the transverse carpal ligament, where increased pressure produces night pain, numbness in the radial digits, and thenar weakness. The ulnar nerve travels through Guyon canal, which is a separate compartment. The radial and posterior interosseous nerves never enter the carpal tunnel.