Must know Flashcards

Question 1

Q

Nonop parameters for metacarpal shaft fractures

Answer

A

no rotational deformity
acceptable shaft shortening 2-5m

index/long finger >10 angulation
ring finger <20 angulation
little finger <30 angulation

Question 2

Q

nonop parameters for metacarpal neck fractures

Answer

A

Index and middle = <10-15°
Ring = <40°
Small = <60°
No rotation

acceptable shaft shortening 2-5m

Question 3

Q

how should malrotation of a MC fracture be assessed?

Answer

A

with the fingers in flexion all should point towards the scaphoid tubercle without overlapping adjacent finger (compare to contralateral side)
for patients who are unable to perform active flexion, the digital cascade can be observed through the tenodesis effect by flexing and extending the wrist
- each degree of rotation at the MC results in 5° of rotation at the fingertip, leading to 1.5cm of digital overlap in the closed fist

Question 4

Q

what is the reduction maneuver described for MC neck fractures

Answer

A

Jahss Maneuver
- MCP and PIP joints are fully flexed and dorsal force is applied along the long axis of the proximal phalanx and volarly along the MC shaft to reduce the MC head from a flexed position

Question 5

Q

What is acceptable alignment for metacarpal head fractures?

Answer

A

No articular displacement acceptable

Question 6

Q

VACTERL

Answer

A

The following features are observed with VACTERL association:
V - Vertebral anomalies
A - Anorectal malformations
C - Cardiovascular anomalies
T - Tracheoesophageal fistula
E - Esophageal atresia
R - Renal (Kidney) and/or radial anomalies
L - Limb defects

Question 7

Q

physeal growth plate zones and associated conditions

Answer

A

Reserve zone (B)
Gaucher’s
Diastrophic dysplasia
Kneist

Proliferative zone (C)
Achondroplasia
Gigantism
MHE

Hypertrophic zone (D)
Zone of chondrocyte maturation, chondrocyte hypertrophy, and chondrocyte calcification
3 phases: maturation, degenerative, provisional calcification
SCFE (not renal)
Rickets (provisional calcification zone)
Enchondromas
Mucopolysacharide disease
Schmids
Fractures most commonly occur through zone of provisional calcification

primary spongiosa (E)
(metaphysis)
Metaphyseal “corner fracture” in child abuse
Scurvy

secondary spongiosa
(metaphysis)
Metaphyseal “corner fracture” in child abuse
Scurvy

Question 8

Q

most active physes in upper/extremity and lower extremity and mm/y

Answer

A

U/E
1. proximal humerus 7mm/y
2. distal radius 5.25mm/y

L/E
1. distal femur 9 mm/y
2. proximal tibia 6mm/y
3. distal tibia 5 mm/y

Question 9

Q

most common causative bacteria in PJI infections of the shoulder

Answer

A

cutibacterium acnes (38.9%)
– gram-positive,facultative, aerotolerant, anaerobic rod that ferments lactose to propionic acid
– concentrated in the axilla within the dermal sebaceous glands
– forms biofilm within 18-90h (found on implant surface and on synovial tissue)&raquo_space; planktonic
– Mean duration of culture incubation between 7-21 days
staph aureus 14.8%
staph epidermidis (14.5%)
coagulase-negative staph (14%)

Question 10

Q

RF of PJI of shoulder

Answer

A

male
higher BMI
younger age
immunosuppressed conditions and meds
post-truma
rTSA
previous surgery

Question 11

Q

What is the cause of swan neck deformity & treatment

Answer

A

laxity/attenuation of volar plate
characterized by hyperextension of the PIP joint and flexion of the DIP joint due to an imbalance of muscle forces on the PIP.

treatment
- volar plate advancement and PIP balancing with central slip tenotomy

Question 12

Q

what is the cause of boutoniere deformity

Answer

A

central slip rupture

Question 13

Q

Goutallier classification

Answer

A

0 Normal
1 Some fatty streaks
2 muscle>fat
3 fat = muscle
4 fat>musclemost tear articular sided, less strong

Question 14

Q

RC repair indications

Answer

A

tear >50% M-L width of supra
acute full-thickness
bursal sided >3mm/>25% in depth
PASTA >7mm of exposed bony footprint w/ >25% healthy bursal sided tissue
young pt with acute traumatic tears
older pt with degenerative tears

Question 15

Q

when do you do lat dorsi transfer

Answer

A

irreparable posterosuperior tears with intact subscap
* young laborer
* radial n + post branch of axillary n. at risk

Question 16

Q

massive RC retear RF

Answer

A

increased fatty infiltration,
decreased acromiohumeral space,
smoking,
size of RC tear, and
increase tension on repair

Question 17

Q

RF associated with lower tendon-bone RC healing following repair

Answer

A

increase age
osteoperosis (ind of age)
smoker
chronic tear
large gap
large size
high tension repair
low initial fixation strength
fatty infiltration
muscle atrophy

Question 18

Q

what are the indications for superior capsular reconstruction?

Answer

A

massive irreparable supraspinatus and/or infraspinatus tear
minimal to no arthritis
functioning deltoid
not suitable for rTSA (young, active)

Question 19

Q

what tendon transfers can be considered for irreparable RC tear?

Answer

A

Lat dorsi for posterosuperior tears
pec major for irreparable anterosuperior tears

Question 20

Q

Innervation of RC muscles

Answer

A

supraspinatus
- suprascapular n.
infraspinatus
- suprascapular n.
teres minor
- posterior branch of axillary n.
Subscapularis
- upper and lower subscap n.

Question 21

Q

what is the rotator crescent

Answer

A

thin, crescent-shaped sheet of rotator cuff comprising the distal portions of the supraspinatus and infraspinatus insertions.

Question 22

Q

rotator cable

Answer

A

thick bundle of fibers found at the avascular zone of the coracohumeral ligament running perpendicular to the supraspinatous fibers and spanning the insertions of the supra- and infraspinatus tendons.

Question 23

Q

triangular interval

Answer

A

3 syllable n.
3 word artery with ‘i’

superior: lower border of teres major
lateral: shaft of humerus
medial: long head of triceps

n: radial
v: profunda brachii artery

Question 24

Q

What are the boundaries of the quadrilateral space? What nerve and vessel run thru the quadrilateral space?

Answer

A

superiorly -teres major

Inferiorly - teres major

Laterally - surgical neck

Medially - long head of triceps

Axillary nerve

Posterior circumflex humeral artery

Question 25

Q

What are the borders and the contents of the Triangular Space?

Answer

A

3 word artery with ‘s’

Inferior - teres major

Lateral - long head of triceps

Superior - inferior border of teres minor

CONTENTS - circumflex scapular artery

Question 26

Q

What is the primary stabilizer to valgus stress at elbow
which band
what is the origin & insertion

Answer

A

anterior bundle of medial collateral ligament
central band
origin: median epicondyle
insertion: sublime tubercle
primary statis stabilizer to valgus stress from 20-120 degrees of elbow flexion

Question 27

Q

superficial flexors of forearm and innervation and origin

Answer

A

PT, FCR, PL, FDS, FCU
all inervated by median n. except for FCU, supplied by the ulnar n.
all originate from common flexor origin on medial epicondyle
FDS also originates on anterior radius

Question 28

Q

deep flexors of forearm, innervation

Answer

A

FDP, FPL, PQ
all innervated by AIN
FDP has dual innervation (ulnar haf by ulnar n., radial half by AIN)

Question 29

Q

muscle of mobile wad and origin

Answer

A

brachioradialis, ECRL, ECRB
* The lateral supracondylar ridge of the humerus serves as an attachment point for the brachioradialis and ECRL, which also has attachments onto the superior aspect of the lateral epicondyle
* ECRB originates on the lateral epicondyle
* AllinnervatedbytheRadialn.

Question 30

Q

superficial extensors of forearm and origin

Answer

A

anconeus, EDC, EDM, ECU
all innervated by PIN except for anconeus, supplied by radial n.
ECU not innervated by ulnar n.

Question 31

Q

deep extensors of forearm

Answer

A

Supinator
Abductor Pollicis Longus
Extensor Pollicis Brevis
Extensor Pollicis Longus
Extensor indicis proprius

all innervated by PIN

Question 32

Q

Sites of compression of the ulnar nerve at the cubital tunnel

Answer

A

Arcade of struthers
Medial intermuscular septum
Medial epicondyle
Osborne’s ligament
Between heads of FCU (fasica)
Aponeurosis of FDS

Question 33

Q

which ligament in the elbow is the primary stabilizer to varus and ER stress

Answer

A

LUCL
origin lateral humeral epicondyle
insertion tubercle of supinator crest of ulnar

Question 34

Q

Varus Posteromedial Rotatory Instability (VPMRI) vs.Valgus Posterolateral Rotatory Instabiliy (VPLRI)
1. radial head
2. coronoid fracture
3. MCL
4. LCL
5. P/E

Answer

A

VPMRI
No radial head fracture
> 15% (anteromedial facet)
Posterior band of MCL ruptured, anterior band intact (attached to anteromedial facet)
LCL complex (includes LUCL) avulsion
Valgus stress, moving valgus, milking maneuver
VPLRI
Radial head fracture
< 15% (coronoid tip)
Anterior band of MCL ruptured
LCL complex (includes LUCL) avulsion
Varus stress, chair rise, lateral pivot shift

Question 35

Q

approach for LUCL reconstruction

Answer

A

kocher approach

Question 36

Q

how to cast simple elbow dislocation post reduction

Answer

A

likely LUCL injury if any lig (most common)
cast in pronation
‘thumb away from injured side’

Question 37

Q

mechanism of injury of LUCL resulting in PLRI

Answer

A

FOOSH with axial compression, in supination and valgus

Question 38

Q

primary ligament injured that leads to PLRI

Question 39

Q

P/E for PLRI

Answer

A

lateral pivot-shift test
- patient lies supine with affected arm overhead; forearm is supinated and valgus stress is applied while bringing the elbow from full extension to 40 degrees of flexion
- with increased flexion, triceps tension reduces the radial head
- often more reliable on anesthetized patient
posterior drawer test
- patient lies supine with affected arm overhead; forearm is supinated and the examiner’s index finger is placed under the radial head and the thumb over it.
- application of a posterior force will cause posterior subluxation of the radial head
prone push up
chair push up
table top relocation test

Question 40

Q

Kocher approach
interval
indications
advantages
disadvantages

Answer

A

interval between the anconeus and extensor carpi ulnaris

indications: radial head #, excision, prosthesis, LUCL recon
advantages: low risk of PIN injury
disadvantage: distal extension may endager PIN
relatively more posterior and thus risks injuring the lateral collateral ligament complex.

Question 41

Q

kaplan approach
interval
indications
advantages
disadvantages

Answer

A

interval between the extensor carpi radialis brevis and extensor digitorum communis

Indications Radial head fractures – fixation, excision and prosthesis.
Advantages Good view of the anterior half of the radial head which is a common site of fracture.
No disruption of the LUCL.
Drawbacks Inadvertent injury to the PIN if the incision is too anterior.
Distal extension can endanger the PIN.

Remember: If there is a supinator crest of ulna fracture or LUCL avulsion as in 5% of terrible triad injuries, this approach should not be used.

Question 42

Q

EDC split approach
interval
advantages

Answer

A

EDC tendon is dissected directly longitudinally starting at its origin at the lateral epicondyle

The approach offers a slightly more anterior access than the Kocher’s approach.

Question 43

Q

Hotchkiss approach (over-the-top)
interval
indications
advantages
disadvantages

Answer

A

Interval: splits the flexor-pronator mass and elevates the anterior part (pronator teres (PT), flexor carpi radialis (FCR), and palmaris longus (PL)) along with brachialis from the anterior elbow capsule
Indications The Hotchkiss or ‘over-the-top approach’ is the most anterior of the medial approaches and provides good access to the tip of the coronoid process and the anterior elbow joint.
Advantages Good view of the coronoid tip fracture site.
Drawbacks Ulnar nerve exploration and visualisation is required.
Possible injury to medial antebrachial cutaneous nerve.

Question 44

Q

Flexor carpi ulnaris (FCU) splitting (Ring) approach
interval
indications
advantages
disadvantages

Answer

A

interval: between the heads of the flexor carpi ulnaris
Indications Coronoid fractures.
Advantages Good view of the fracture site especially the anteromedial facet.
Drawbacks Ulnar nerve exploration is required.
Possible injury to medial antebrachial cutaneous nerve.

Question 45

Q

Taylor and Scham approach
approach
interval
indications
advantages
disadvantages

Answer

A

Interval - For access to the base consider elevating the entire flexor-pronator mass from posterior to anterior
Indications This is a good approach for a medial plate fixation for a large basilar fracture of the coronoid.
Advantages Good view of the fracture site.
Drawbacks Ulnar nerve exploration is required.
Possible injury to medial antebrachial cutaneous nerve.

Question 46

Q

Which muscle shares the same origin site as the tendon that undergoes angiofibroplastic hyperplasia during the pathogenesis of tennis elbow?

Answer

A

anconeus

Lateral epidondylitis is classically thought to be caused by histopathologic angiofibroblastic hyperplasia at the origin of the extensor carpi radialis brevis. ECRB originates from the common extensor wad, that also includes ECRL, ED, ECU. The anconeus shares the same attachment site at the lateral epicondyle as the ECRB

Question 47

Q

which extensor muscle of the forearm originates on lateral supracondylar ridge

Question 48

Q

what tendon is most commonly implicated in lateral epicondylitis

Question 49

Q

what is the underlying histopathology in lateral epicondylitis
what are the histological findings in lateral epicondylitis

Answer

A

tendinosis (degenerative condition) rather than tendinitis (inflammation)
- angiofibroblastic hyperplasia
- characterized by dense populations of fibroblasts, vacular hyperplasia and disorganized collagen

Question 50

Q

how to avoid iatrogenic injury to LUCL with lateral epicondylitis release

Answer

A

do not extend beyond equator of radial head
may lead to PLRI

Question 51

Q

what is valgus extension overload

Answer

A

describes collection of injuries in the medial, lateral and posterior aspects of the overhead thrower’s elbow
occurs as a consequence of the large valgus loads and rapid elbow extension during the throwing motion

Question 52

Q

what are the common presenting symptoms of valgus extension overload in over head thrower’s

Answer

A

decreased performance (velocity, control, fatigue)
posteromedial elbow pain with full extension of elbow
locking/catching (loose bodies), loss of terminal elbow extension
ulnar nerve symptoms (neuritis, subluxation)
pain in deceleration of throwing phase

Question 53

Q

complication of surgical procedure for valgus extension overload syndrome

Answer

A

valgus instability - over-resection of posteromedial ostephy past its native margin or >3mm may lead to increased stress on the MCL and valgus instability

Question 54

Q

what are the components of the lateral collateral ligament of the elbow

Answer

A

lateral ulnar collateral ligament
- inserts on the supinator crest
radial collateral liagement
- inserts on the annular ligament
annular ligament
- inserts on the supinator crest
accessory lateral collateral ligament
- inserts on the supinator crest

Question 55

Q

what are the components of medial ulnar collateral ligaments of the elbow and which is the most important for valgus stability

Answer

A

anterior bundle
- strongest and most significant stabilizer to valgus stress
- insert - sublime tubercle
- provides stability between 30-120° flexion
- subdivides into anterior and posterior bands
  - anterior band - 1° restraint to valgus stress, exhibiting nearly isometric strain during elbow ROM
posterior bundle
- greatest change in tension from flexion to extension
- tighter in flexion
transverse bundle

Question 56

Q

what is the most sensitive test for diagnosis of medial elbow instability

Answer

A

moving valgus test (100% sensitive, 75% specific)

Question 57

Q

What are preventative strategies to avoid UCL injuries in pitchers?

Answer

A

Limit pitching to 100 innings in a calendar year
Do not pitch for multiple teams
Do not pitch all year (3 month rest period advised)
No pitching on consecutive days
No pitching in a game or practice after being removed from a game
No breaking pitches (curveballs/sliders) until puberty
Proper pitching mechanics and year round conditioning should be stressed
Avoid pitching while fatigued

Question 58

Q

where do partial distal biceps tendon tears primarily occur

Answer

A

on radial side of tubersosity footprint

Question 59

Q

RF for biceps tendon tear

Answer

A

high BMI, smoking, anabolic steroids

Question 60

Q

contents of antecubital fossa

Answer

A

medial) median nerve, brachial a., biceps tendon, radial n. (lateral)

Question 61

Q

when is LABC most at risk during surgery for biceps tendon repair

Answer

A

during surgical disseciton btw biceps and brachialis

Question 62

Q

distal biceps anatomy and insertion

Answer

A

The tendon externally rotates 90°
- Brings the medial short head fibres anterior and the lateral long head fibres posterior
The tendon inserts with:
- Short head fibres distal on the radial tuberosity
  - Stronger flexor
- Long head fibres proximal
  - Stronger supinator

Question 63

Q

What are the reported deficits with nonoperative management of complete distal biceps tears?

Answer

A

Supination

79% endurance [50% loss]
21-55% strength [40% loss]

Flexion

10-40% strength [30% loss]
30% endurance

Question 64

Q

intervals for single incision technique for biceps repair

Answer

A

proxial - BR and brachialis
distal - BR and PT

Answer 62

A

Forearm held in supination to protect the PIN and bring the radial tuberosity into view

Answer 63

A

affects traversing/descending/lower nerve root at L4/5 - affects L5 nerve root
most common PLL is weakest here

Answer 64

A

less common (5-10%)
affects exiting/upper nerve root
at L4/5 affects L4 nerve root

Answer 65

A

Pronator syndrome (SLAPS)
* **Struther’s ligament **Resisted Flexion at 120
* **Lacertus fibrosis **resisted flexion with supinated forearm
* **Arch of FDS **(sublimus arch) resisted FDS middle finger
* Pronator Teres (2 heads) resisted supination with elbow flexed

Answer 66

A

Motor
Order:
- Forearm
- Pronator teres
- FCR
- Palmaris longus
- FDS

     - Radial FDP [AIN]
         - Index and middle finger
     - FPL [AIN]
     - Pronator quadratus [AIN]
 - Hand
     - APB
     - FDB (superficial head)
     - OP
     - Lumbricals 1 & 2

Answer 67

A

Sensory
1. volar wrist capsule, radial palm and palmar aspect of thumb, index, long and radial half of ring
  1. terminal AIN
  2. palmar cutaneous branch of median nerve
  3. terminal digital cutaneus branch

Answer 68

A

Lies medial to brachial a. at the elbow
Passes between the two heads of the pronator
teres and then runs between FDS and FDP

Answer 69

A

Carpal tunnel borders
- scaphoid tubercle and trapezium radially
- hook of hamate and pisiform ulnarly
- transverse carpal ligament palmarly (roof)
- proximal carpal row dorsally (floor)
Carpal tunnel contents
- four flexor digitorum superficialis (FDS) tendons
- four flexor digitorum profundus (FDP) tendons
- flexor pollicis longus (FPL)
  - most radial structure
- median nerve

Answer 70

A

bilateral AIN signs caused by viral brachial neuritis
be suspicious if motor loss is preceded byintense shoulder pain and viral prodrome

Answer 71

A

FDP (index and middle finger)
FPL
pronator quadratus

Answer 72

A

AIN Syndrome
* Forearm pain
* Weakness of grip and pinch - FPL, FDP 1&2, PQ
* * unable to make OK sign
* No sensory disturbance

Pronator Syndrome
* Pain in proximal, volar forearm
* Paresthesias in thumb, index, long fingers
* AIN Syndrome PLUS weakness of all digits & wrist flexion
* Exacerbated by resisted pronation
* Tinel’s at anterior elbow

Answer 73

A

potential sites of entrapment of AIN
- tendinous edge of deep head of** pronator teres**
  - most common cause
    ** - fibrous arch of the FDS**
    ** - aberrant vessels**
    ** - accessory head of FPL(Gantzer’s muscle)**
- accessory muscle from FDS to FDP
- abberant muscles (FCRB, palmaris profundus)

Answer 74

A

should havecharacteristics differentiating from carpal tunnel syndrome (CTS)
- aching painover proximal volar forearm
- sensory disturbances over thedistribution of palmar cutaneous branch of the median nerve(palm of hand)
  - arises 4 to 5 cm proximal to carpal tunnel
- lack of night symptoms

Answer 75

A

less clawing
sensory deficit to dorsum of the hand
motor deficit to ulnar-innervated extrinsic muscles
Tinel sign at the elbow
positive elbow flexion test

Answer 76

A

floor:Transverse carpal ligament, hypothenar muscles
roof: Volar carpal ligament
ulnar border: Pisiform and pisohamate ligament, abductor digiti minimi muscle
radial border: Hook of hamate

ulnar nerve, a/v

Answer 77

A

zone I - proximal to bifurcation (motor and sensory)
zone II - deep motor branch (motor only)
zone III - superifical sensory branch (sensory only)

Answer 78

A

Motor
- FCU
- Ulnar half of FDP
- All intrinsics except lateral 2 lumbricals and thenar muscles
  - Except deep head of FPB
Sensory
- Elbow joint
- Ulnar palm and dorsum of hand including small finger and ulnar half of ring finger
- Branches:
  - Articular branch of the elbow
  - Dorsal cutaneous branch
  - Palmar cutaneous branch
    - Only present in 58% of people
  - Terminal superficial branch

Answer 79

A

Medial intermuscular septum
Arcade of Struthers
Triceps fascia
Osborne ligament** (most common site)**
- Roof of cubital tunnel
Medial epicondyle
FCU
- Deep fascia
- Between two heads
FDS/FDP fascia
Anconeus epitrochlearis
- Anomalous muscle which arises from medial border of olecranon & adjacent triceps & inserts into the medial epicondyle
Canal of Guyon

Answer 80

A

numbness/paresthesia of the small and ulnar half of ring finger (ulnar palm and dorsum are spared)
intrinsic muscle weakness (thenar spared)

Answer 81

A

FREAS (radial nerve)
* Fascia superficial to radiocapitallar joint
* Radial Recurrent Vessels (Leash of Henry)
* ECRB tendinous proximal margin at origin
* Arcade of Frohse (prox aponeurotic/tendinous edge of sup, most common site of PIN entrapment)
* Supinator (distal edge of)

Answer 82

A

Borders:
- Proximal border – begins at radiocapitellar joint
- Distal border – arcade of Froshe
- Roof – BR
- Medial border – brachialis and biceps tendon
- Lateral border – ECRB, ECRL, BR

Answer 83

A

Pain at lateral forearm distal to lateral epicondyle
Lack motor and sensory changes

Answer 84

A

motor
common extensors
* ECRB (often from radial nerve proper, but can be from PIN)
* Extensor digitorum communis (EDC)
* Extensor digiti minimi (EDM)
* Extensor carpi ulnaris (ECU)
deep extensors
* Supinator
* Abductor pollicis longus (APL)
* Extensor pollicus brevis (EPB)
* Extensor pollicus longus (EPL)
* Extensor indicis proprius (EIP)
sensory
* sensory fibers to dorsal wrist capsule - provided by terminal branch which is located on the floor of the 4th extensor compartment
* no cutaneous innervation

Answer 85

A

triceps brachii, anconeus, brachioradialis, extensor carpi radialis longus, brachialis

Answer 86

A

Provocative maneouvers
- Pressure over supinator muscle in supinated position
- Pain with resisted wrist or long finger extension

Answer 87

A

fibrous tissue anterior to the radiocapitellar joint
between the brachialis and brachioradialis
“leash of Henry”
are recurrent radial vessels that fan out across the PIN at the level of the radial neck
extensor carpi radialis brevis edge
medio-proximal edge of the extensor carpi radialis brevis
“arcade of Fröhse”
which is the proximal edge of the superficial portion of the supinator
supinator muscle edge
distal edge of the supinator muscle

Answer 88

A

Weakness of PIN innervated muscles
- Sparing of BR, ECRL
Pain in dorsal radial forearm
no sensory changes
Wrist extension demonstrates radial deviation
- Intact ECRL
resisted supination
- will increase pain symptoms

Answer 89

A

Compression of the superficial radial nerve ~9cm proximal to radial styloid where the nerve passes between BR and ECRL
Characterized by:
- Dorsal radial forearm pain radiating to dorsoradial hand
- more common inwomen
- SRN compressed by scissoring action ofbrachioradialisandECRL tendonsduringforearm pronation
- provocative test: wrist flexion, ulnar deviation and pronation for one minute
- De Quervain’s tenosynovitis: pain is not aggravated by wrist pronation,

Answer 90

A

cleland’s ligament (c for feiling
- dorsal to digital nerve

Answer 91

A

A2 and A4

Answer 92

A

EPB + APL = De Quervain’s tenosynovitis
ECRB + ECRL = intersection syndrome
EPL = drummer’s wrist, traumatic rupture with DR #
EDC + extensor indicis = extensor tenosynovitis
EDM = Vaughn-Jackson syndrome
ECU = snapping ECU

Answer 93

A

DISI (dorsal intercalated segmental instability)
- Division of the dorsal component of the SLIL results in gradual collapse of the scaphoid into flexion, while the lunate is pulled into extension to form the dorsal intercalated segment instability pattern
- Diagnosis of DISI deformity can be made with lateral wrist radiographs showing
  - a scapholunate angle > 70 degrees. (N 30-60)
  - DISI defined by radiolunate angle >15°

Answer 94

A

Widened SL distance
1. gap >3mm with clenched fist view (terry thomas sign)
Cortical ring sign
1. caused by schaphoid malalignment
Shortening of the scaphoid
Scapholunate angle >70° (normal = 30-60)
Lunate extension
DISI defined by radiolunate angle >15°

Answer 95

A

scapholunate advanced collapse
- describes a pattern of wrist arthritis that occurs following a scapholunate ligament injury

Watson Classification
Stage I - radial styloid
Stage II - radioscaphoid joint
Stage III - capitolunate joint
[Stage IV - pancarpal involvment (controversial)]

Answer 96

A

Stage I - scaphoid and radial styloid arthritis
- radial styloidectomy
- PIN and AIN denervation
Stage II - scaphoid/scaphoid facet of radius arthritis
- proximal row carpectomy
  - contraindicated with caputolunate arthritis because capitate articulates with lunate fossa of the distal radius
  - contraindicated if there is an incompetent radioscaphocapitate ligament
  - advantages - greater postop ROM (flexion, extension, total flexion/extension arc), lower complication rate
  - others - earlier ROM no hardware
- scaphoid excision and 4 corner fusion
- advantages - greater radial deviation ROM, greater grip strength
Stage III - pan carpal arthritis
- scaphoid excision and 4 corner fusion
- wrist fusion
  - wrist fusion gives best pain relief and good grip strength at the cost of wrist motion

Answer 97

A

synovitis and significant edema

Answer 98

A

major blood supply isdorsal carpal branch (branch of the radial artery)
- enters scaphoid in a nonarticular ridge on the dorsal surface and supplies proximal80% of scaphoidvia retrograde blood flow
supplies proximal80% of scaphoidvia retrograde blood flow
minor blood supply fromsuperficial palmar arch (branch of volar radial artery)
- entersdistal tubercle andsupplies distal 20% of scaphoid

Answer 99

A

In the normal wrist:
- Scaphoid links the proximal and distal carpal rows
  - Proximal row moves with the scaphoid
- Scaphoid has a tendency to assume a flexed posture
- Capitate longitudinal load on the lunate is eccentric causing the lunate and triquetrum to extend
- These forces are balanced as long as the link between the scaphoid and lunate are intact
With scaphoid nonunion
- The distal scaphoid flexes
- The proximal scaphoid extends with the lunate and triquetrum

Answer 100

A

Stage I - radial styloid
Stage II - proximal scaphocapitate joint
Stage III - capitolunate joint
- Initially, degeneration occurs between the radial styloid and radial side of the distal scaphoid fragment
- Degeneration does not progress proximally in the radioscaphoid joint because the proximal scaphoid relationship with the lunate is maintained
- Degeneration progresses to the midcarpal joint starting with the proximal scaphocapitate joint then the capitolunate joint

Answer 101

A

3rd metacarpal shaft

Answer 102

A

10-15° of extension, slight ulnar deviation

Answer 103

A

Hemiresection-interposition
Ulnar shortening osteotomy
‘Wafer’ resection
Sauve-Kapandji
- DRUJ fusion with proximal pseudoarthrosis
Darrach
- Complete distal ulna resection
Arthroplasty

Answer 104

A

humpback deformity (distal pole flexes over the volar radioscaphocapitate ligament)

results from volar angulation of the proximal and distal poles of the scaphoid in the setting of scaphoid fracturethrough the waist

The dorsal component forms a ‘humpback’ which can be palpated

Answer 105

A

Delayed union (<6 months)
- ORIF with headless compression screw
1. Established nonunion without humpback
  - ORIF with headless compression screw + bone graft (cancellous ICBG or distal radius)
2. Nonunion with humpback deformity; no AVN
  - ORIF via volar approach + corticocancellous bone graft
3. AVN without humpback deformity
  - Vascularized bone graft via volar or dorsal approach
4. AVN with humpback deformity
  - Vascularized medial femoral condyle bone graft via volar approach

Answer 106

A

Lichtman Classification
- Stage I
  - Normal xray
  - MRI decreased signal T1
  - Bone scan positive
- Stage II
  - Lunate sclerosis
- Stage IIIa
  - Lunate collapse (no scaphoid rotation)
  - Carpal height maintained
- Stage IIIb
  - Lunate collapse
  - Carpal collapse
  - Scaphoid rotation (hyperflexed, RS angle >60°)
    - Cortical ring sign
    - Capitate migrates proximal
    - Decreased carpal height
- Stage IV
  - Pancarpal arthritis (Kienbock’s disease advanced collapse)

Answer 107

A

Stage I (normal xray, mri decreased signal t1)
- Nonoperative (3 months immobilization)
Stage II (lunate sclerosis)
- Radial shortening osteotomy
  - If ulnar negative or neutral
- Capitate shortening
  - If ulnar positive
- (vascularized bone graft)
Stage IIIa (lunate collapse)
- Same as Stage II
- Vascularized bone graft (dorsal pedicle)
  - 4,5 ECA graft
  - Vascularized pisiform
  - Free vascularized medial femoral condyle
Stage IIIb (lunate/capitate collapse and scaphoid rotation)
- Scaphocapitate fusion
- STT fusion
- PRC
Stage IV (pancarpal arthritis)
- PRC
- Total wrist arthrodesis

Answer 108

A

dorsal 4 + 5 extensor compartment artery (ECA) pedicled VBG

Answer 109

A

what are surgical management options for DRUJ arthritis
- darrach procedure
  - indications
    - preferred for low demand and nonreconstructable joint
  - technique
    - subperiosteal distal ulna exposure
    - distal ulna resection just proximal to sigmoid notch
    - preserve soft tissue
      - TFCC, ECU sheath, periosteum
- hemiresection
  - indications -required intact TFCC
  - technique
    - classic -resection of articular distal ulna with remainder left insitu including TFCC attachment
    - hemi-resection interposition technique (HIT)
      - resection as classic
      - soft tissue interposition into void to prevent radioulnar convergence (capsular flap or free tendon)
- sauve-kapandji procedure
  - indications - preferred for young, active patient with nonreconstructable joint
  - technique
    - dorsal or ulnar approach preserving soft tissue
    - identify and protect the dorsal cutaneous branch of the ulnar nerve
    - ulnar neck resection just proximal to sigmoid (~10-15mm)
    - sigmoid notch and ulnar head prepared for fusion (Cancellous bone)
    - DRUJ fusion with 2 k-wires or 3.5mm screw (neutral ulnar variance)
    - pronator quadratus interposed in osteotomy site (prevents re-ossificaiton)
    - FCU slip can be tenodesed through drill hole in ulnar stump to prevent instability
- partial ulnar head arthroplasty
  - indication - isolated DRUJ arthritis without instability
    - failed HIT
- total ulnar head arthroplasty
  - indications - painful instability after failed resection, isolated instability
  - requires stability from native soft tissues
- total DRUJ arthroplasty
  - indications - incompetent native soft tissues, salvage option after failed distal ulnar resection

Answer 110

A

bone contour (sigmoid notch of radius and ulnar head)
TFCC
ulnocarpal ligament complex
ECU
ECU tendon sheath
pronator quadratus
interosseous membrane
DRUJ joint capsule

Answer 111

A

nonop
- acute dislocation
  - closed reduction and splinting in stable position for 6 weeks
    - dorsal radioulnar ligament injury - splint midsupination
    - volar radioulnar dislocaiton - splint midpronation
operative
- acute DRUJ instability indications
  - irreducible
    - open reduction +/- DRUJ pinning +/- TFCC repair +/- ulnar styloid fracture fixation
  - associated fractures
    - ORIF of associated fractures often resolves the instability
    - if remains unstable pin in reduced position
  - TFCC tear
    - open or arthroscopic repair
      - open - dorsal interval between 5 & 5 compartment, TFCC repaired to distal ulnar with anchor or suture tunnels
    - reconstruction if repair fails
- chronic DRUJ instability
  - in absence of arthritis
    - distal radius malunion
      - indications for correction = >20° of dorsal angulation (controversial)
      - correct distal radius malunion then assess DRUJ stability
        if still unstable reconstruct the DRUJ
    - reconstruction
      - indications - TFCC or radioulnar ligament repair failure, unrepairable
      - Adams procedure +/- notchplasty (if flat lesser sigmoid)
        dorsal approach between 5-6 compartments and PL graft radius and ulna
    - bain procedure
      - indication
        
        chronic DRUJ instability with a TFCC foveal tear and stable radial attachment
        
        positive arthroscopic hook and trampoline test
      - technique
        dorsal approach via 5th extensor compartment, PL graft in TFCC and ulna
  - in presence of arthritis
    - darrach with ulnar stump stabilization
    - sauve-kapandji

Answer 112

A

recommended views
- AP radiograph with wrist in neutral supination/pronation and zero rotation
  - required to evaluate ulnar variance
- pronated grip view
  - increases radiographic impaction
findings
- ulna positive variance
- sclerosis of lunateand ulnar head

Answer 113

A

Ulnar shortening osteotomy
- Technique
  - Subcutaneous approach to the ulna
  - Osteotomy at junction of distal and middle 1/3
  - Compression plate
    - Volar surface preferred
  - Goal of 0 to -1mm ulnar variance
- Advantages
  - Addresses ulnar styloid carpal impaction concomitantly
  - Decreases dorsal subluxation of distal ulna
  - Larger shortening can be achieved compared to wafer
  - Stabilizes ulnar ligament complex
    - Preferred if associated LT ligament injury
- Disadvantages
  - Nonunion
  - Hardware irritation
Wafer procedure
- Technique
  - Open or arthroscopic
  - Resection of thin wafer of dome of ulnar head
- Advantage
  - Less revision compared to shortening osteotomy (hardware removal)
  - No nonunion
- Disadvantage
  - Limit resection to 2-3mm
  - Does not address associated ulnar styloid carpal impaction
  - Does not improve dorsal ulnar subluxation
  - Does not tighten ulnar ligament complex

Answer 114

A

Articular disc
* Extends between the volar and dorsal radioulnar ligaments (hammock)
Meniscus homologue
Volar and dorsal radioulnar ligaments
* Superficial and deep (ligamentum subcruentum)
* Major stabilizers of the DRUJ
Sheath of ECU
Ulnar capsule (ulnar collateral ligament)
* Arises from the ulnar styloid and extends between the ulnotriquetral ligament and the ECU sheath
Ulnolunate and ulnotriquetral ligaments (volar)

Answer 115

A

Prominent ulna
Fovea sign
- Palpation of the depression volar between ulnar styloid, FCU and pisiform
- Tenderness suggests:
  - Tear of ulnotriquetral ligament
  - Foveal disruption of TFCC
  - Chondromalacia of ulnar aspect lunate
    - Suggestive of ulnocarpal impaction
Ulnocarpal stress test
- Ulnar deviation with axial loading in alternating supination and pronation
Positive grind test
- Clicking, crepitus or pain with passive supination and pronation
Lunotriquetral shuck test
- Pain and laxity when examiner grasps the pisiform/triquetrum and lunate with opposite hands and translates volar and dorsal

Answer 116

A

extended wrist with forearm pronation

Answer 117

A

Nonoperative
- Most tears are initially treated nonoperative
Operative
- Contraindications:
  - Severe OA
  - Previous infection
  - Severe osteoporosis of ulnar head
- Open
  - Indicated when fixing distal radius fracture or surgeon not familiar with arthroscopy
- Arthroscopic
  - Palmar 1A – debridement
  - Palmer 1B, C, D – repair
    - Transosseous or suture anchor fixation
- Ulnar positive wrists
  - Perform ulnar shortening osteotomy or wafer procedure at time of TFCC repair
    - Better outcomes

Answer 118

A

Proper collateral ligament
* Taut in flexion
Accessory collateral ligament and volar plate
* Taut in extension

Answer 119

A

UCL

Proximal phalanx avulsion (90%)
Midsubstance and metacarpal avulsion less common

RCL
* Variable, more common proximal at metacarpal

Answer 120

A

Distal edge of the avulsed UCL is displaced proximal to the adductor aponeurosis
* Blocked from reapproximation to its insertion on the proximal phalanx
Surgical management is recommended

Answer 121

A

Grade 1

Sprain with no joint instability

Grade 2

Incomplete tear with asymmetric joint laxity
Instability does not meet the criteria for a complete tear
- Characterized by increased laxity with a firm end point, or an incomplete tear

Grade 3

Complete tear with joint instability
- Laxity of >35° in 0° and 30° of flexion
  - Or 15° greater than that of the contralateral side

Answer 122

A

RCL
* Adductor pollicis inserts on the proximal phalanx and ulnar sesamoid creating an ulnar and volar deforming force
Assess with anterior drawer test
* >3mm displacement volar is more common with RCL injury

Answer 123

A

Grade 1 and 2

Nonoperative
- Cast or splint x 4 weeks
- Grip and pinch strengthening after 6 weeks

Grade 3

Surgical
- Acute collateral ligament injury = repair
  - Avulsion from proximal or distal insertion
    - Suture anchor repair
  - Midsubstance tear
    - Direct repair
- Chronic collateral ligament injury (>3 weeks)
  - No arthritis
    - Ligament reconstruction with free graft (palmaris longus)
  - Arthritis = arthrodesis

Answer 124

A

DIP arthritis > CMC arthritis

Answer 125

A

Eaton and Littler Classification of Basilar Thumb Arthritis

Stage I
- Normal joint with widening
  - Synovitis, effusion, ligamentous laxity
Stage II
- Mild joint narrowing
- Mild subchondral sclerosis
- Subchondral cysts and/or periarticular debris
Stage III
- Severe joint space narrowing
- Subchondral sclerosis/cysts
- Larger periarticular debris
Stage IV
- Involves scaphotrapezial joint

Answer 126

A

Nonoperative
- Exercise therapy, heat, education, magnetotherapy, adaptive equipment, orthoses, NSAIDs, corticosteroid injections
Operative
- Joint preserving options described (Stage I/II)
  - 1st metacarpal extension osteotomy
  - Arthroscopy and debridement
  - Imbrication of the dorsoradial capsule
  - Volar beak ligament reconstruction
- Joint sacrificing options described (Stage III/IV)
  - Trapeziectomy
  - Trapeziectomy and ligament reconstruction and tendon interposition (LRTI)
  - Distraction hematoma arthroplasty
  - Suture suspension arthroplasty
  - Prosthesis
  - CMC arthrodesis

Answer 127

A

Advanced age
- 36% >80y vs. 6.6% 40-49y
Female
Ligamentous laxity/ higher Beighton score
Occupations
- Repetitive finger use or heavy manual labour
Post-traumatic
- Intra-articular fracture
- Traumatic ligamentous instability

Answer 128

A

Dorsoradial
dorsoradial ligament

Answer 129

A

Traction
Abduction
Pronation
Dorsal pressure on the base of the metacarpal (anatomical snuffbox)

Answer 130

A

Anteromedial (volar-ulnar) fragment

Smaller (less articular surface area)
Nondisplaced, attached to volar oblique ligament

Metacarpal fragment

Larger (greater articular surface area)
Displaced
- Proximal, dorsal and radial

Answer 131

A

APL = proximal, dorsal, radial
Adductor pollicis = narrowing of 1st web space

Answer 132

A

Traction
Abduction
Pronation
Pressure to the metacarpal base (dorsal to palmer)

*TrAPP/TAPP

Answer 133

A

Wagner approach

Junction of the glabrous and nonglaborus skin
Elevate thenar muscles and perform capsulotomy

Answer 134

A

Large anteromedial fragment
- Open reduction and direct screw fixation
Small anteromedial fragment
- CRPP – transarticular or intermetacarpal
Irreducible or intra-articular gap >2mm [J Hand Surg 2009;34A:945–952.]
- Open reduction

Answer 135

A

‘T’ or ‘Y’ pattern

Extra-articular fracture separating metadiaphysis from epiphysis and a vertical fracture separating the epiphysis into two fragments
Central joint depression may be present

Answer 136

A

Open or arthroscopic reduction

- Followed by provisional K-wire fixation and miniplate fixation or definitive k-wire fixation

Answer 137

A

<30° of angulation
1. >30 results in unacceptable narrowing of the 1st web space

Answer 138

A

Extension (most common)
Axial load of a flexed PIP joint

Answer 139

A

Volar plate rupture or avulsion of volar base off middle phalanx
Volar avulsion of variable size (loss of buttress effect)

Answer 140

A

Stable

Articular surface <30% involvement
Clinical stability = stable throughout ROM

Tenuous

Articular surface = 30-50% involvement
Clinical stability = Requires ≤30° of PIP flexion to maintain reduction

Unstable

Articular surface >50% involvment
Clinical stability = Requires >30° of PIP flexion to maintain reduction

Answer 141

A

Stable
* Buddy taping
Tenuous

Extension block splinting (if no hinging)
- Prevents extension of the PIPJ into the range where it is unstable while permitting motion within the stable range

Unstable

Operative options
- Extension block pinning or transarticular pinning +/- percutaneous pinning of large fracture fragment
  - Indicated when concern for closed reduction failure or digit will not accommodate extension block splint (swollen, short, small digit)
- Dynamic distraction and external fixation (Suzuki splint)
- ORIF
  - Large fragments
- Volar plate arthroplasty
  - Comminuted and impacted volar fragment
  - <50% articular surface involvement
- Hemi-hamate resurfacing arthroplasty
  - Comminuted and impacted volar fragment
  - >50% articular surface involvement

Answer 142

A

Hyperflexion
Axial load of an extended PIP joint

Answer 143

A

Central slip rupture or avulsion of dorsal base of middle phalanx
Dorsal avulsion of variable size

Answer 144

A

Stable and small minimally displaced fracture

<50% articular surface and <2mm displacement
PIP joint splinting

Stable and large or displaced fracture

>50% articular surface and >2mm displacement
CRPP or ORIF

Unstable with minimally displaced fracture
* Dynamic distraction and external fixation

Answer 145

A

dorsal dislocation

Answer 146

A

avulsion of volar lip/FDP

Answer 147

A

associated with avulsion of dorsal lip/terminal tendon

Answer 148

A

volar plate
FDP

Answer 149

A

terminal tendon interposition

Answer 150

A

Apex volar

Proximal fragment flexes due to interosseous attachments
Distal fragment extends due to extensor central slip

Answer 151

A

Apex dorsal if fracture proximal to FDS insertion
Apex volar if fracture distal to FDS insertion

Answer 152

A

No rotation
<10-15° angulation
<2mm shortening

Answer 153

A

displaced distal phalangeal physeal fractures with an associated nailbed injury.
resuls from hyperflexion
presents asmallet deformity(i.e. apex dorsal) due to
- terminal tendon attaches to proximal epiphyseal fragment
- FDP attaches to distal fragment

Answer 154

A

the digital nerve is palmar/volar to the artery in the finger

sensation is performed with the pads (nerve is palmar) of your fingers and you test for cap refill at the fingernail (artery is dorsal)

Answer 155

A

injury of the terminal extensor mechanism resulting in loss of active extension at the level of the DIPJ
injury is characterized by extensor tendon disruption, either isolated or in combination with a distal phalanx avulsion fracture

Answer 156

A

- D.I.P. joint osteoarthritis
- Swan Neck Deformity
- Hyperextension at the level of the PIP joint as a result of proximal retraction of the central slip

Answer 157

A

nonop
- no associated fracture
- no volar subluxation of the distal phalanx
- fracture involving <30% of the articular surface
operative
- open
- fracture involving >30% of the articular surface
- palmar subluxation of the distal phalanx

Answer 158

A

A1 - MCP volar plate

A2 - proximal phalanx

C1 - between A2-A3

A3 - PIP volar plate

C2 - between A3-A4

A4 - middle phalanx

C3 - between A4-A5

A5 - DIP volar plate

Answer 159

A

A2 and A4

Answer 160

A

A1 - MCP volar plate

Oblique pulley - proximal half of proximal phalanx

A2 - IP volar plate

Answer 161

A

Oblique pulley

Answer 162

A

Zone 1 - distal to FDS insertion

Zone 2 - FDS insertion to proximal A1 pulley

Zone 3 - proximal A1 pulley to distal transverse carpal ligament

Zone 4 - carpal tunnel

Zone 5 - proximal transverse carpal ligament to musculotendinous junction

Answer 163

A

Easy placement of sutures in the tendon
Secure knots
Smooth juncture of the tendon ends
Minimal gapping
Minimal interference with tendon vascularity
Sufficient strength

Answer 164

A

Minimal tendon handling to minimize adhesion
Strength of repair is proportional to the number of core sutures and caliber of suture
Core sutures should be 7-10mm from tendon edge
Dorsal placement is biomechanically advantaged
Epitendinous (peripheral) suture improves:

Strength
Minimizes gapping
Reduces CSA
Decreases gliding friction

Locking loops increase tensile repair
Internal knots have decreased strength

Answer 165

A

Pathways

Intrinsic = tenocytes within the tendon
Extrinsic = inflammatory cells outside the tendon
- Implicated in adhesions/scarring

Phases

Inflammatory (0-72h)
- Strength of repair is equivalent to strength of suture repair
Proliferative (72h-4 weeks)
- Type III collagen laid down
- Strength increases
Remodeling phase (>4 weeks - 112 days)
- Type I collagen laid down
- Strength increases
  - Does not reach preinjury

Answer 166

A

Tendon sheath

Fibrocartilaginous metaplasia
Cartilage degradation
Vascular ingrowth

Tendon

Chronic degenerative tears
- Absence of inflammatory cells

Answer 167

A

A1 pulley

Answer 168

A

Ring finger and thumb

Answer 169

A

Female
Diabetes
RA
Crystalline arthropathy
Thyroid disease
Renal insufficiency
Overuse

Answer 170

A

Carpal tunnel syndrome

>60% of patients with trigger digits demonstrate clinical or electrodiagnostic evidence of median nerve compression at the wrist

Answer 171

A

Puncture wound (most common)
Staph aureus (most common)

Answer 172

A

Symmetric swelling of entire digit
Tenderness along course of tendon sheath
Semiflexed posture
Pain with passive extension of digit

Answer 173

A

Northern European
Caucasian
Male
Family history
* Autosomal dominant
Advanced age
Smoking
Alcohol
Local trauma
Local infection
Diabetes (type I > type II)
Epileptic medication
Manual labour

Answer 174

A

Myofibroblasts

Answer 175

A

Pretendinous cord

[Normal fascial bands become pathologic cords]

Answer 176

A

Transverse ligament of the palmar aponeurosis
Cleland ligament

Answer 177

A

Pretendinous cord = MCP contracture
Central cord = PIP contracture
Lateral cord = PIP or DIP contracture
Natatory cord = web space contracture
Spiral cord = displaces NV bundle superficial and to midline
* MCP and PIP contracture

Answer 178

A

Ring finger

Followed by:
- Small
- Long
- Index
- Thumb

Answer 179

A

MCP before PIP

Answer 180

A

Palmer to digital

Answer 181

A

Peyronie disease (penile fibromatosis)
Ledderhose disease (plantar fibromatosis)

Answer 182

A

Indications
* ≥30° MCP joint contracture
* >15° PIP joint contracture
Techniques
* Fasciotomy
* Limited fasciectomy
* Dermofasciectomy
* Radical fasciectomy (healthy and diseased fascia)

Answer 183

A

Rheumatoid nodules
Caput ulnae syndrome

Dorsal subluxation of the distal ulna
- Prominent ulnar head

Carpal deformity
* Classically, palmar translation, ulnar translation, supination, radial deviation
DISI or VISI
Arthritis
* Usually progression from DRUJ, radiolunate/radioscaphoid, pancarpal arthritis
Extensor tendon

Tenosynovitis
EDQ rupture
EDC rupture
7. Flexor tendon
Tenosynovitis
Carpal tunnel syndrome
FPL rupture over prominent distal scaphoid and trapezium (Mannerfelt syndrome)
FDS and FDP rupture
8. Ulnar drift
9. Volar subluxation of proximal phalanx to MCP joint
10. Swan neck deformity
11. Boutonniere deformity

Answer 184

A

Darrach procedure

Favoured in low demand, elderly patients
Main concern in RA is ulnar translation of carpus (weak ligamentous support)

Sauve-Kapandji

Favoured in active, younger patients
Main concern in RA is less predictable fusion

Answer 185

A

Thumb amputation
Multiple digit amputation
Amputations at or proximal to the palm
Pediatric finger amputation at any level
Single digit amputation in Zone I (relative)

Answer 186

A

Single digit amputation through Zone II
Severe crush, mangled or contaminated amputation
Segmental injuries
Prolonged warm ischemia time
Medically unfit

Answer 187

A

Red line sign

Red stripe along the mid lateral aspect of the avulsed digit
Represents hemorrhage along the vessel

Ribbon sign

Tortuous, spiraled blood vessels are seen
Indicates significant intimal injury

Answer 188

A

Elson test

The examiner holds the PIP joint in 90° of flexion and instructs the patient to actively extend the DIP joint
With an intact extensor mechanism, holding the PIP joint in 90° of flexion causes slack in the lateral bands as they are held distally by their attachments to the central slip
- The patient is unable to generate any extension power at the DIP joint
With a boutonnière injury, flexion of the PIP joint does not advance the lateral bands distally secondary to disruption of the central slip
- Tension is generated in the terminal tendon because of the disrupted central slip
- Therefore, the patient is able to generate an abnormal amount of active extension at the DIP joint with the PIP joint held in flexion

Answer 189

A

Bunnell test

A patient with intrinsic muscle tightness will have a decrease in passive and active flexion of the PIP joint with the MP joint held in extension

Answer 190

A

Postaxial (ulnar) polydactyly (most common)
Preaxial (radial) polydactyly
* Involves the thumb
Central polydactyly (rare)

Answer 191

A

Type A

Well-formed digit with osseous connection

Type B

Incompletely-formed with soft tissue connection
- Nonfunctional

Answer 192

A

Type I

Bifid distal phalanx

Type II

Duplicated distal phalanx (2nd most common)

Type III

Bifid proximal phalanx

Type IV

Duplicated proximal phalanx (most common)

Type V

Bifid metacarpal

Type VI

Duplicated metacarpal

Type VII

Any triphalangeal thumb

Answer 193

A

Mannerfelt syndrome
- rupture of FPL due to scaphoid spur
- treatment
  - FDS4 to FPL tendon transfer + excision of scaphoid spurs (may also lead to rupture index FDP2)
  - tendon graft + spur excision
  - IPJ fusion (for advanced disease)

Answer 194

A

Vaughan-Jackson syndrome describes the rupture of the hand digital extensor tendons, which start on the ulnar side of the wrist first and then move radially. This is thought to occur from DRUJ instability, resulting in dorsal prominence of the ulnar head, leading to an attritional rupture of the extensor tendons.

Extensor digiti minimi is the extensor tendon commmonly ruptured. (5th compartment)

Answer 195

A

Destruction of the DRUJ leads to caput ulnae syndrome: dorsal dislocation of the distal ulna, supination of the carpus on the radius, and volar subluxation of the extensor carpi ulnaris tendon.

The “piano keyboard sign” is indicative of DRUJ instability and is elicited when the ulnar head is depressed volarly and rebounds as pressure is released.

A “Z collapse pattern” is observed as the carpus translates ulnarly, the metacarpals deviate radially, followed by ulnar deviation of the fingers.

Darrach distal ulna resection
- must also relocate ECU dorsally with a retinacular flap or perform ECU stabilization of ulna
ulnar hemiresection
Sauvé-Kapandji(ulnar pseudoarthrosis)
- has advantage of preserving the TFCC
- good option for younger patients

Answer 196

A

CN IX, X, XI

travel in jugular foramen adjacent to occipital condyle

Answer 197

A

Traumatic – often fatal
Acquired – often associated with Down’s syndrome

Answer 198

A

Harris lines (Harris rule of 12s)

Basion-dens interval
- Normal = <12mm
- Distance from basion to tip of dens
Basion-axis interval
- Normal = 4-12mm
- Distance between line parallel to posterior cortex of C2 and basion

Powers ratio [Orthobullets]

Distance from basion to posterior arch C1/distance from opisthion to anterior arch C1
- Normal = 1
- >1 = anterior dislocation
- <1 = posterior dislocation, dens fracture, ring of atlas fracture

Wackenheim line

Line parallel along the posterior portion of the clivus to the upper cervical spine
- Normal = tip of dens is <1-2mm from Wackenheim line

Answer 199

A

Atlanto-dens interval (ADI)

Distance between anterior dens and posterior aspect of anterior arch of C1
Normal = <3mm in adults
>3mm indicates transverse ligament disruption and C1-C2 instability

Lateral atlanto-dens interval

Distance between the lateral surface of the dens and the medial surface of the lateral mass of C1
Normal = <2mm of asymmetry

Combined lateral mass overhang

Combined horizontal distance from lateral border of C1 to lateral border of C2 on open mouth radiographs or coronal CT
Normal = <7mm
>7mm indicates transverse ligament rupture and C1-C2 instability

Answer 200

A

Landells Classification

Type I - isolated anterior or posterior arch fracture
Type II - Jefferson burst fracture (bilateral anterior and posterior arch fractures)
Type III - unilateral lateral mass fracture

Answer 201

A

Dickman classification

Type I - intrasubstance tear
Type II - bony avulsion from tubercle at lateral mass of C1

Answer 202

A

Atlanto-dens interval
* Normal <3mm in adults (<5mm in children)
Space available for the cord – SAC (posterior atlantodens interval – PADI)
* Normal >13mm

Answer 203

A

Anderson and D’Alonzo Classification

Type I - odontoid tip fracture
- Oblique fracture due to bony avulsion of the alar ligament
Type II - base of the dens fracture
- Does not involve the C2 superior articular facet
- High non-union rate due to watershed area
Type III – C2 body fracture
- Does involve the C2 superior articular facet

Grauer modification

Type IIA - transverse fracture, <1mm displacement
Type IIB- oblique fracture extending from anterosuperior to posteroinferior
Type IIC- oblique fracture extending from anteroinferior to posterosuperior
- May be associated with significant anterior comminution

Answer 204

A

Type I

Stable fractures (at least one alar ligament and the transverse ligament is intact)
- Cervical collar
Unstable fractures (associated craniocervical dissociation)
- Posterior C0-C2 fusion

Type II

Young patient
- No risk factors for nonunion = halo immobilization
- Risk factors for nonunion = surgery
Elderly patient
- Surgical candidate = surgical stabilization
  - Posterior C1-C2 fusion
- Not surgical candidate = cervical orthosis
  - Results in fibrous union in most cases
  - Halo vest is associated with high rate of morbidity and mortality in elderly
    3. Type III
Cervical orthosis

Answer 205

A

Age >40
Posterior displacement >5mm
Angulation >11°
Comminution
Fracture gap >1mm
Delay in treatment (4 day delay)
Concomitant neurological injury

Answer 206

A

Levine and Edwards Classification

Type I
- Minimally displaced pars interarticularis fracture
- Translation <3mm of C2, no angulation
- MOI = axial load and hyperextension
Type Ia
- Oblique fracture through one pars interarticularis and anterior to the pars within the body of the contralateral side (unstable)
Type II
- Translation >3mm of C2
- MOI – axial load and hyperextension followed by flexion
Type IIa
- Angulation (kyphosis) more than translation
- MOI = flexion-distraction
Type III
- Similar pars fracture as type I plus C2/C3 facet dislocation
- MOI = flexion distraction followed by hyperextension
- ***Note: hyperextension causes the pars fracture and flexion causes PLL and disc rupture

Answer 207

A

Type I - hard cervical orthosis (12 weeks)

Type Ia - halo immobilization

Type II - halo immobilization (12 weeks)

Type IIa

C2-C3 ACDF or posterior fixation [JAAOS 2014;22:718-729]
Reduction with gentle axial load + hyperextension, then compression halo immobilization for 6-12 weeks [Orthobullets]

Type III - posterior reduction and stabilization

C2-C3 or C1-C3 fusion

Answer 208

A

Allen and Ferguson

6 classes based on mechanism of injury and static radiographs (used in research)
Flexion-compression, vertical compression, flexion-distraction, extension-compression, extension-distraction, lateral flexion

Subaxial Injury Classification System (SLIC)

Three components
- Morphology
- Integrity of the discoligamentous complex
- Neurological status
Score dictates treatment
- <4 = conservative treatment
- 4 = treatment at discretion of surgeon
- >4 = surgical treatment

Answer 209

A

Compression fracture

Characteristics = anterior vertebral height loss, posterior vertebrae not involved
Nonoperative
- Indicated if stable and PLC intact
  - Facet joints are not subluxed or dislocated
  - No vertebral translation
  - Minimal gapping of interspinous spaces
  - Kyphosis <11°
- Rigid cervical collar for 3 months followed by flex-ex views
Operative
- Indicated if unstable or neurological deficit
  - Facet joint subluxation or dislocation
  - Vertebral translation
  - Gapping of interspinous spaces
  - Kyphosis >11°
  - MRI findings suggestive of PLC disruption
- Anterior or posterior stabilization

Burst fracture

Characteristics = comminuted vertebral body fracture involves the posterior vertebral body often with retropulsed fragments
Nonoperative:
- Indicated if no PLC disruption, no neurological deficit (rare)
- Halo vest or rigid cervicothoracic orthosis
Operative:
- Indicated if PLC disruption, neurological deficit
- Anterior corpectomy
- Plus posterior instrumentation and fusion if PLC is disrupted

Flexion teardrop fracture

Characteristics = oblique fracture line from anterior vertebral body to the inferior endplate (quadrangular fragment)
- May have posterior translation of the posterior vertebral body
- PLC disruption suggested by interspinous and facet gapping
Nonoperative
- Minimally displaced, little kyphosis, intact PLC
- Rigid cervical collar
Operative
- Neurological deficit, PLC disruption
  - Posterior VB translation, kyphosis >11°
- ACDF

Extension teardrop fracture

Characteristics = small avulsion from anterior vertebral body
Nonoperative
- Considered a stable injury
- Rigid cervical collar

Answer 210

A

Facet subluxation
Unilateral facet dislocation (25% displacement on XR)
Bilateral facet dislocation (50% displacement on XR)
Complete dislocation (100% displacement on XR)

Answer 211

A

Presence of a disc herniation can lead to neurological injury upon reduction/realignment of the cervical spine
Herniations with disc material posterior to the displaced vertebral body are most concerning

Answer 212

A

Obtain MRI

Neurologically intact patient
- No urgency to perform reduction, if disc is present you can convert a neurologically intact patient to one with deficits if reduction performed
Obtunded, nonexaminable patient
- If neurologically intact, reduction in presence of disc may lead to neurological deficit
Planning posterior approach and reduction
Failed closed reduction or neurological deterioration during closed reduction [Orthobullets]
2. Omit MRI
Awake, alert, cooperative patient with incomplete cord injury or worsening neurological deficit
- Patient would benefit from immediate reduction rather than delaying for MRI
Complete cord injury

Answer 213

A

Requires an awake, alert and cooperative patient
Gardner-Wells tongs are applied

Pins 1cm above the pinna of the ear in line with the external auditory meatus below the equator of the skull
Placement slightly posterior produces flexion moment (often desirable in cervical facet dislocation)
Skin is prepped and lidocaine injected subcutaneously and subperiosteally
Pins are tightened until indicator pin protrudes at least 1mm
3. 10lbs of weight is applied initially then 5-10lbs added incrementally
After each weight – lateral radiograph and neurological examination
Apply additional weight after 10-15mins

Once reduction is achieved the weight can be reduced to approximately 10-20lbs to maintain reduction

Answer 214

A

Presence of disc herniation
Absence of disc herniation (if surgeon prefers over posterior)

Answer 215

A

synchondroses between ossification centers
1. neurocentral synchondroses - between posterior elements and body
2. dentocentral synchondroses - between dens and body of C2
3. normal = smooth with subchondral sclerotic lines
increased elasticity of ligaments, capsule and enplates
wedge-shaped vertebral bodies
1. normal = ≤ 3mm of anterior wedging
horizontally oriented facet joints
virtually absent uncinate processes
pseudosubluxation of C2 and C3
1. normal = spinolaminar line (swichuk’s line) between C1-3 should pass within 1mm of C2 spinolaminar junction
2. abnormal = >1.5mm of displacement
loss of cervical lordosis in neutral position
increased ADI
1. normal = 3-5mm

Note - pediatric spine adops a more adult configuration by age 8

Answer 216

A

sciwora = spinal cord injury without radiographic abnormality
- refers to ‘objective signs of myelopathy resulting from trauma with no evidence of ligamentous injury or fractures on plain radiographs or CT
- occurs as a result of greater elasticity of spinal structures in pediatric population
more common in younger children but may occur at the age of 16
traditionally treated by external immobilization for up to 3 months to allow tissues to heal
- at 3 months a flexion-extension radiograph is performed to ensure no instability

Answer 217

A

Anterior column = anterior half/part of vertebral body/disc and ALL
Middle column = posterior half/part of vertebral body/disc and PLL
Posterior column = posterior elements including pedicles, facets, lamina, spinous process and ligaments

***NOTE – based on this system fractures extending into the middle column are largely considered unstable

Answer 218

A

AP view = widened interpedicular distance
Lateral view = loss of height of posterior cortex

Answer 219

A

Thoracolumbar Injury Classification and Severity Score (TLICS)

3 injury characteristics
- Injury morphology
- Neurological status
- Integrity of PLC
Score dictates treatment
- <4 = nonsurgical
- 4 = nonsurgical or surgical
- >4 = surgical

AO Thoracolumbar Classification (Morphology)

TYPE A = Compression Injuries
- A0 = Minor, nonstructural fractures
  - Fractures which do not compromise the structural integrity of the spinal column (eg. transverse process and spinous processes)
- A1 = Wedge-compression
  - Fracture of a single endplate without involvement of the posterior wall of the vertebral body
- A2 = Split
  - Fracture of both endplates without involvement of the posterior wall of the vertebral body
- A3 = Incomplete burst
  - Fracture with any involvement of the posterior wall; only a single endplate fractured
  - Vertical fracture of the lamina is usually present and does not constitute a tension band failure
- A4 = Complete burst
  - Fracture with any involvement of the posterior wall and both endplates
  - Vertical fracture of the lamina is usually present and does not constitute a tension band failure
TYPE B = Distraction Injuries
- B1 = Transosseous tension band disruption (Chance fracture)
  - Monosegmental pure osseous failure of the posterior tension band
- B2 = Posterior tension band disruption
  - Bony and/or ligamentary failure of the posterior tension band together with a Type A fracture
  - Type A fracture should be classified separately
- B3 = Hyperextension
  - Injury through the disc or vertebral body leading to hyperextended position of the spinal column
  - Commonly seen in ankylotic disorders
  - Anterior structures, especially ALL are ruptured but there is a posterior hinge preventing further displacement
TYPE C = Translation Injuries
- C = Displacement/dislocation
  - There are no subtypes because various configurations are possible due to dissociation/dislocation
  - Can be combined with subtypes of A or B

Answer 220

A

Neurologically intact
<25° kyphosis
<50% vertebral height loss
<50% canal compromise
Intact PLC

Answer 221

A

Asia A: Complete

No motor or sensory function preserved in sacral elements

Asia B: Incomplete

Sensory but not motor function preserved below neurological level

Asia C: Incomplete

Greater than half the muscles below affected level are < antigravity power (<3/5)

Asia D: Incomplete

Greater than half the muscles below affected level are > antigravity (>3/5)

Asia E: Normal

Answer 222

A

temporary loss of motor (flaccid paralysis), sensation and reflexes as a result of an acute spinal cord injury
state of complete areflexia as demonstrated by loss of bulbocavernosus reflex secondary to an acute spinal cord injury
the significance is that thee extent of the neurologic injury cannot be determined until the spinal shock has resolved
spinal shock is resolved upon return of the bulbovacernosus reflex
1. usually resolves within 24h from time of injury
2. bulbocavernosus test = clinical test to assess the integrity of the intact S3-S4 arc, performed by squeezing the glans penis, placing pressure on the clitoris, or tugging on a foley catheter
3. an intact reflex will result in contraction of the anal sphincter

Answer 223

A

hypotension and bradycardia 2° to loss of sympathetic tone as a result of an acute spinal cord injury
typically occurs with an acute spinal cord injury above the level of T6

Answer 224

A

ipsilateral loss of all sensory modalities at the level of the lesion
ipsilateral flaccid paralysis at the lecel of the lesion
ipsilateral spastic paraparesis below the lesion
ipsilateral loss of vibration and position sense below the lesion
contralateral loss of pain and temperature below the lesion

Answer 225

A

loss of pain, temperature, crude touch sensations below the level of the lesion
loss of motor below the level of the lesion
orthostatic hypotension, bladder and/or bowel incontinence and sexual dysfunction
preservation of fine touch, proprioception and vibration

Answer 226

A

loss of fine-touch, proprioception and vibration below the level of the lesion
preservation of motor, pain, temperature, crude touch

Answer 227

A

lower extremity weakness (mixed UMN and LMN deficits)
main difference between cauda equina syndrome (only LMN deficits)
saddle anesthesia
bowel and bladder dysfunction
impotence

Answer 228

A

L1 vertebral body (T12-L2 vertebra)

Answer 229

A

Collection of peripheral nerves (L1-S5) in a common dural sac within the lumbar spinal canal
Therefore, lesions involving the cauda equina are lower motor neuron lesions

Answer 230

A

Cervical nerve roots exit above their numbered pedicles
* Except C8 which exits above T1
Exiting nerve roots affected
* Eg. C5-C6 disc herniation affects the C6 nerve root

Answer 231

A

C6 and C7

Answer 232

A

Unilateral neck pain
Upper trapezial and interscapular pain
Radiculopathy patterns/Symptoms

C2
- Posterior occipital headaches, temporal pain
C3
- Occipital headache, retro-orbital or retroauricular pain
C4
- Base of neck, trapezial pain
C5
- Lateral arm pain
- Motor loss - Deltoid
- Reflex - Biceps
C6
- Radial forearm pain, pain in the thumb and index fingers
- Motor loss - Biceps, wrist extension
- Reflex - Brachioradialis
C7
- Middle finger pain
- Motor loss - Triceps, wrist flexion
- Reflex - Triceps
C8
- Pain in the ring and little fingers
- Motor loss - Finger flexors
T1
- Ulnar forearm pain
- Motor loss - Hand intrinsics

Answer 233

A

Inherited predisposition
Congenital stenosis

Answer 234

A

Degenerative disc (anterior)
Uncovertebral joint osteophyte (anterior)
Hypertrophied/infolded ligamentum flavum (posterior)
Facet joint degeneration (posterior)

Answer 235

A

>10° rigid kyphosis

1 or 2 levels of compression = anterior approach
- ACDF/Corpectomy
3+ levels of compression = combined anterior and posterior
- Anterior corrects kyphosis and decompresses
- Posterior decompresses

<10° rigid kyphosis

1 or 2 levels of compression = anterior approach
- ACDF/Corpectomy
3+ levels of compression = posterior approach
- Laminectomy + fusion OR laminoplasty

Answer 236

A

C5 palsy (4.6% of patients)

Thought to be due to posterior migration of the spinal cord with tethering of the nerve root

Answer 237

A

low signal on T1
clasically also have high signal on T2

Answer 238

A

Replacement of the PLL with lamellar bone

Answer 239

A

East Asians
Male
DISH
Hyperparathyroidism
Hypophosphatemic rickets
Hyperinsulinemia
Obesity

Answer 240

A

Line from center of the spinal canal at C2 to center of canal at C7
Assesses the affect of the size of OPLL and the cervical lordosis
Negative K-line = OPLL protrudes posterior to the K-line
Positive K-line = OPLL protrudes anterior to the K-line
Significance = negative K-line is a negative predictor of outcome for posterior surgery alone

Answer 241

A

OPLL occupies >60% of the canal
Loss of cervical lordosis

Answer 242

A

OPLL (greatest risk factor for cervical spine surgery)
Revision surgery
Surgeon inexperience
Age

Due to:
- Narrowing of the spinal canal
- Thicker ligamentum flavum
- Osteophyte formation
- Redundant dura due to shortening of the spine

Answer 243

A

Ensure proper visualization

Dry field
Adequate hemostasis
Loupes or microscope

Primary repair when possible

Augment as necessary
- Fat grafts, fibrin glue, collagen matrix, hydrogels
Dural grafts when primary closure not possible
- Fascia lata, lumbodorsal fascia

Test the repair for watertight closure

Deflated dura should inflate in pulsatile fashion
Test repair with Valsalva
- Duration of 15-20 sec, supine posture, and 40 mmHg intrathoracic pressure [Can J Anesth (2018) 65: 578.]

Tight fascial and wound closure in layers
Bedrest until symptoms of CSF leak resolve

Cervical durotomy – position patient upright
Lumbar durotomy – position patient supine
Symptoms managed with opiods, NSAIDs, antiemetics, caffeine

Answer 244

A

Positional headache
Nausea
Photophobia
CSF leak from wound or subfascial drain

Answer 245

A

B-2 transferrin assay

Answer 246

A

Up to 95% at L4-L5 and L5-S1

Answer 247

A

Central

Causes back pain
Can cause cauda equina

Paracentral (posterolateral)
* Affects the descending nerve root (L4/5 affects L5)
Foraminal (far lateral)
* Affects the exiting nerve root (L4/5 affects L4)

Answer 248

A

Protrusion
* Eccentric bulging through an intact anulus fibrosus
Extrusion
* Disc material crosses the disrupted anulus fibrosus but is continuous with the disc space
Sequestered

Free fragment
Disc material is not continuous with the disc space

Answer 249

A

Achondroplasia

Congenitally short pedicles
Thick lamina
Interpedicular distance that decreases caudally

Answer 250

A

Central
* Disc-osteophyte complex and ligamentum flavum hypetrophy
Lateral recess
* Facet hypertrophy and osteophytes
Foraminal

Loss of disc height
Foraminal disc protrusion
Osteophyte
Scoliosis

Extraforaminal
* Far lateral disc herniation

Answer 251

A

Facet arthrosis

Answer 252

A

Sagittally oriented facets (congenital)
Transitional lumbosacral L5 /sacralization of L5

Answer 253

A

1.Central and lateral recess stenosis

A. Caused by slippage, hypertrophied ligamentum flavum, facet arthrosis
B. Affects descending L5 nerve root

2.Foraminal stenosis

A. Caused by
- i. Vertical stenosis – due to loss of disc height and posterolateral osteophytes from vertebral body compressing nerve root against inferior pedicle
- ii. Anterosuperior stenosis – due to facet arthrosis and posterior vertebral body osteophytes
B. Affects exiting L4 nerve root

Answer 254

A

Pars interarticularis defect (spondylolysis)

Answer 255

A

L5 spondylolysis (L5 on S1)

Answer 256

A

Slip <50% = low grade (Grade I-II)
Slip >50% = high grade (Grade III-V)

Answer 257

A

Degenerative

Level = L4-5
Central Stenosis = present
L5 nerve compression = at origin

Isthmic

Level = L5-S1
Central Stenosis = absent
L5 nerve compression = foramen

Answer 258

A

1.Pelvic balance

Balanced = SS > PT
Unbalanced = SS < PT

2.Spinopelvic balance

Balanced = C7 plumb line falls over or behind the femoral heads
Unbalanced = C7 plumb line falls infront of the femoral heads

Answer 259

A

Staph aureus

Answer 260

A

Lumbar spine

Answer 261

A

Thoracic spine

Answer 262

A

Caseating granuloma

Answer 263

A

Peridiscal (most common)

Begins adjacent to a single vertebral end plate (metaphysis)
Spreads peripherally to the adjacent intervertebral disc
- Less severely affected and relatively preserved
Tracks deep to the ALL to spread to an adjacent vertebra

Central

Abscess formation in the central vertebral body
Leads to vertebral collapse and spinal deformity

Anterior

Begins anterior to the vertebral body and posterior to the ALL
Spreads under ALL, scallops vertebral body and may extend multiple levels

Answer 264

A

Nonspecific – WBC, ESR, CRP
Tuberculin skin test
* Positive = induration >5-15mm after 48-72 hours
Interferon gamma release assay
* Blood test equally sensitive but more specific
PCR
CXR
* Segmental or lobar infiltrates with ipsilateral hilar or mediastinal lymphadenopathy
Thoracolumbar xray

Osteolysis of affected vertebra
Kyphotic deformity (late)

MRI

T1 - Homogenous low signal with subligamentous spread
T2 – Heterogenous high signal with subligamentous spread

CT guided biopsy

Diagnostic yield = 42-76%
If nondiagnostic consider open biopsy
Send biopsy for:
- Aerobic, anaerobic and tuberculous-specific culture (broth cultures)
- Acid-fast bacilli smear microscopy
- PCR
- Pathology (detects caseating granuloma)

Answer 265

A

Atlantoaxial instability → atlantoaxial impaction → subaxial instability

Answer 266

A

Atlantoaxial impaction

Collapse of the lateral masses due to involvement of the atlanto-occipital and atlantoaxial joints
- Erosion of O-C1 and C1-2 joints such that odontoid appears to enter foramen magnum
  - Weakening and collapse of the lateral masses

Atlantoaxial instability

Due to weakening or rupture of the transverse, alar and apical ligaments
- Synovitis and pannus weaken the transverse, alar and apical ligaments
Repetitive strain leads to stretching or rupture
Bony erosion of dens or atraumatic dens fractures possible

Subaxial instability

Due to destabilization of the facet joints with weakening of the facet capsule and interspinous ligaments
- Destruction of facet joints and uncovertebral joints
  - Weakening of interspinous ligaments
Lack of osteophyte formation results in relative instability
- Versus stability in OA due to osteophytes
Disc and annulus also degenerative but synovitis does not develop
- Thus, anterior disease does not directly contribute to instability

Answer 267

A

Atlantoaxial impaction

McCrae’s line
- Line between basion and opisthion
- Normal = tip of dens should be below line
McGregor’s line
- Line between hard palate and base of the occiput
- Abnormal = tip of dens 4.5mm above line
Ranawat Index
- Distance from midpoint of C2 pedicle along centre of odontoid to horizontal line through C1
- Abnormal = <15mm in males, <13mm in females
Cervicomedullary angle (MRI)
- Angle between anterior aspect of cervical cord and anterior medulla
- <135° indicates impending neurological impairment
Clark’s station
- C2 divided into thirds (1 is superior, 3 is inferior)
- Abnormal = anterior ring of C1 is in the 2nd or 3rd station
- Simplest method to use as the relationship does not change in flexion, extension or neutral
***McRae and McGregors inaccurate with odontoid erosion
2. Atlantoaxial instability
ADI (atlantodental interval)
- Distance between the anterior dens and the posterior anterior arch of C1
- Abnormal = >3.5mm
  - >5mm suggests instability
  - >10mm suggests complete loss of ligamentous integrity
PADI/SAC
- Posterior atlantodental interval/space available for the cord
- Distance between the posterior dens and the posterior arch of C1
- Abnormal = ≤14mm is an indication for surgery
  - Need 14mm for canal (10 cord, 1 dura, 1 CSF)
  - <10mm assoc with poor neuro outcomes
  - ≥14mm assoc with excellent neuro outcomes
- Better predictor of neuro outcomes than ADI
***ADI and PADI can not evaluate cord compression by soft tissues (i.e. pannus)
3. Subaxial instability
C2/3 and C4/5 most commonly involved
Kyphosis
“staircase” when multiple levels involved
Facet joint erosions and widening
Spindling of the spinous processes
Subluxation
- Abnormal = >4mm or 20% listhesis of vertebral body diameter

Answer 268

A

Intractable pain
Neurologic deficits
ADI >10 [Orthobullets]
PADI ≤14mm
Dens migration ≥5mm rostral to McGregor’s line
Subaxial subluxation with canal diameter ≤14mm
Cervicomedullary angle <135°

***Increased function and lifespan compared to non-op

Answer 269

A

Flowing ossification along the anterolateral aspect of at least 4 contiguous vertebra
Preservation of disc height and relative absence of degenerative changes
Absence of facet joint or SI joint ankylosis

Answer 270

A

Thoracic spine (right sided due to aorta)

Answer 271

A

Lower cervical spine followed by thoracolumbar junction

Answer 272

A

1. bilatearl symmetric sacroiliitis
  1. initial widening, progressive sclerosis to eventual fusion
2. marginal syndesmophytes development
  1. shiny corner sign (sclerosis of the annulus fibrosus insertion into the endplate)
  2. romanus lesion (erosion of the annulus fibrosus insertion into the endplate)
  3. squaring of the vertebral body
  4. marginal syndesmophyte (ossification of the outer annulus fibrosus fibers)
3. bamboo spine
  1. continuous marginal syndesmophytes giving a bamboo stalk appearance indicating ankylosis
4. ankylosis of the facet joints
5. trolley track sign on AP view
6. central line of ossification (supraspinous and interspinous ligaments ) with 2 lateral lines of ossificaiton (facet joints)
7. osteopenia
8. dural ectasia

Answer 273

A

thoracic kyphosis with anterior wedging of ≥ 5° of at least 3 consecutive vertebral bodies
(rigid thoracic hyperkyphosis >45°, apex usually T6-8)

Answer 274

A

narrowed disc space, irregular endplates, schmorl nodes

Answer 275

A

Indications

Painful osteoporotic compression fracture that does not improve with 2 to 3 weeks of nonsurgical care
Patient hospitalized as a result of painful osteoporotic fracture
Painful pathologic fracture
Aggressive hemangioma of the spine
Kümmell disease
- Post traumatic AVN of vertebral body

Absolute Contraindications

Asymptomatic fractures
History of vertebral body osteomyelitis
Allergy to bone fillers or opacification agents
Irreversible coagulopathy

Relative Contraindications

Presence of radiculopathy
Bone retropulsion against neural structures
Greater than 70% collapse of vertebral body height
Multiple pathologic fractures
Lack of surgical backup to manage potential complications

Answer 276

A

Rotation of the atlantoaxial complex that is held in a fixed position as a result of muscle spasm or a mechanical block to reduction

Answer 277

A

New, fixed torticollis
Head held in classic “cock robin” position
* Head tilted to one side and chin rotated to the side opposite the facet subluxation
Pain in the neck or jaw
No preexisting history of congenital muscular torticollis, significant trauma or congenital abnormality

Answer 278

A

Spine

Thoracic > lumbar > cervical

Answer 279

A

Modified Tokuhashi scoring system
* high score is good, low score is bad

6 components
- Karnofsky performance status
- Number of extraspinal metastases foci
- Number of metastases in the vertebral body
- Metastases to the major internal organs
- Primary site of cancer
- Palsy (neurological status)
Score:
- 0-8 = life expectancy ≤ 6 months
  - Conservative treatment versus palliative
- 9-11 = life expectancy ≥ 6 months
  - Palliative surgery
- 12-15 = life expectancy ≥1 year
  - Excisional surgery

Answer 280

A

SINS (Spinal Instability Neoplastic Score)

6 components
- Location
- Pain
- Bone lesion
- Radiographic spinal alignment
- Vertebral body collapse
- Posterolateral involvement of spinal elements
Score:
- 0-6 = stable
- 7-12 = impending instability
- 13-18 = unstable

Answer 281

A

A decision making framework for making treatment decisions in patients with spinal metastasis
Considers 4 factors:

Neurologic
- Degree of spinal cord compromise
  - Radiographic assessment (degree of epidural spinal cord compression)
Oncologic
- Radiosensitive vs. radioresistant tumors
Mechanical (instability)
- Mechanical pain (movement related)
- SINS score
Systemic
- Ability of patient to tolerate intervention
  1. Determines treatment options based on above factors including:
Conventional external beam radiation
Stereotactic radiosurgery
Decompression/separation surgery
Stabilization surgery

Answer 282

A

Radiosensitive = “NOMS LBP”

Neuroendocrine (carcinoid/pancreatic)
Ovarian
Myeloma
Seminoma
Lymphoma
Breast
Prostate

Radioresistant = “SMRT Cancers”

Sarcoma
Melanoma
Renal
Thyroid
Colorectal
adenocarcinoma lung

Answer 283

A

Location = primarily posterior elements
Presentation

Back pain, often night pain, relieved with NSAIDs
Avg age is 19
Most common cause of painful scoliosis in adolescents
- Lesion typically on concavity of curve

Imaging

Radiographs – area of sclerosis
CT – better defines lesion
MRI – better for preop planning to assess proximity to neural structures

Treatment

Nonoperative – first line (NSAIDs)
Radiofrequency thermal ablation – failed nonop
En bloc resection – indicated for:
- Fixed spinal deformity
- Neurological compression
- RFA unsafe

Answer 284

A

Location = posterior elements
Presentation

Dull back pain, possible neural compression
Differs from osteoid osteoma in that not worse at night, does not respond to NSAIDs, less frequently associated with scoliosis

Imaging

Radiographs
- Compared to osteoid osteoma:
  - Multiple calcifications
  - Aggressive bony destruction
  - Infiltration into surrounding tissues
CT – better defines lesion and location
MRI – better assess neural and soft tissue involvement

Treatment
* En bloc resection +/- fusion if instability created

Answer 285

A

Anterior lesions:
1. hemangioma
2. EG
3. GCT
4. osteosarc
5. ewing (ant +sacrum)

Posterior lesions:
1. Osteoblastoma
2. Osteoid osteoma
3. Osteochondroma
4. ABC (start posterior)
5. Metastasis

Answer 286

A

Curve magnitude

Thoracic curve >50° and lumbar curve >40° progress 1° per year after skeletal maturity
Curve >30° at peak growth velocity will likely require surgery

Skeletal maturity

Tanner stage
- Females with Tanner <3 have greatest risk of progression
Risser grade
- Peak growth velocity is Grade 0
Age of menarche
- Peak growth velocity is just before onset of menses
Triradiate cartilage
- Open triradiate have the greatest risk of progression

Answer 287

A

Age <10
Males
Abnormal curve pattern
* Left thoracic or right lumbar curve
Rapid curve progression
Abnormal neurological exam
Apical thoracic kyphosis
Persistent neck pain and headache
Preoperative planning to evaluate for dural ectasia in patients with neurofibromatosis, Ehlers-Danlos and Marfans

Answer 288

A

Lenke classification

Requires upright AP and lateral and supine left and right bending
4 steps
- STEP 1 – divide spine into 3 regions
  - Proximal thoracic – Apex at T3, T4 or T5
  - Main thoracic – Apex between T6 and the T11-T12 disc
  - Thoracolumbar/Lumbar – T/L apex between T12 and L1, and lumbar apex between the L1-L2 disc and L4
- STEP 2 – determine the major and minor curves
  - Curve with largest Cobb angle is the major curve
  - Other curves are minor
- STEP 3 – determine if minor curves are structural or nonstructural
  - Curve is structural if:
    - Residual curve >25° in coronal plane on the bending film
    - Kyphosis >20 in sagittal plane (regardless of coronal flexibility)
- STEP 4 – based on above information determine the curve type
  - For LENKE 4 – Main Thoracic OR TL/L can be the Major Curve
- STEP 5 – determine lumbar and sagittal modifiers
  - Lumbar modifier – draw the CSVL and compare to lumbar apical vertebra
    - A = line is between pedicles of apical vertebra
    - B = line touches pedicle
    - C = line does not touch vertebra or pedicle
  - Sagittal modifier – assess kyphosis from T5-T12
    - ‘-‘ (hypo) = kyphosis <10
    - ‘N’ (Normal) = kyphosis 10-40
    - ‘+’ (hyper) = kyphosis >40

Answer 289

A

Cobb angle
* Superior endplate of the upper end vertebra, to the inferior endplate of the lower end vertebra
End vertebra

Define the ends of a curve in a frontal or sagittal projection
- Cephalad EV – first vertebra from apex whose superior surface is tilted maximally toward the concavity of the curve
- Caudal EV – first vertebra from apex whose inferior surface is tilted maximally toward the concavity of the curve

Neutral vertebra
* Vertebra without axial rotation
Stable vertebra
* Thoracic or lumbar vertebra cephalad to a lumbar scoliosis that is most closely bisected by CSVL assuming the pelvis is level
Apical vertebra
* Vertebra most deviated laterally from the CSVL

Answer 290

A

Curves 20-40° and Risser 0-1
Curves 30-45° and Risser 2-3 should also be considered for bracing
Curves >25 during growth [SRS Guidelines]

Answer 291

A

Curve apex above T7 = Milwaukee CTLSO [Orthobullets]
Curve apex below T7 = Boston TLSO [Orthobullets]

Answer 292

A

Thoracic curve >50°
Lumbar curve >45°

Answer 293

A

Congenital/Structural/Thoracogenic
Neuromuscular
Syndromic
Idiopathic

Answer 294

A

Rib-Vertebra Angle Difference (RVAD)

AKA Mehta angle
Most reliable indicator
RVAD = angle formed between a line perpendicular to the end plate of the apical vertebra and a line from the midpoint of the rib head to the midpoint of the rib neck
- Concave RVA – Convex RVA = RVAD
RVAD >20° = high risk of curve progression
RVAD <20° = curve more likely to resolve
2. Phase 2 relationship
Rib head overlaps the apical vertebra
Implies that progression is certain

Cobb angle >20^o

Answer 295

A

Failure of vertebral body formation

Hemivertebra (unilateral formation failure)
- Fully segmented, partially segmented, unsegmented
  - Segmented if normal disc present
- Incarcerated or nonincarcerated
  - Incarcerated = within the curve
    - Pedicle of hemivertebra is inline with adjacent pedicles
    - Adjacent vertebral bodies conform in their shape
    - Less disruption of spinal curvature
  - Nonincarcerated = outside of the curve
    - Pedicle of hemivertebra is outside the line of adjacent pedicles
    - Typically fully segmented
    - More disruption of spinal curvature (adjacent vertebrae do not accommondate)
Wedge vertebra (unilateral partial formation failure)

Failure of vertebral body segmentation

Block vertebra
Unilateral bars
Unilateral bars with contralateral hemivertebra

Multiple congenital rib fusions (thoracogenic)

Answer 296

A

Echocardiogram
Renal US
MRI spine
C-spine radiographs

Answer 297

A

Long, C-shaped curve
Pelvic obliquity
Kyphosis

Answer 298

A

T2-pelvis

Answer 299

A

Down syndrome
Marfan and Ehlers-Danlos
Neurofibromatosis
OI
Klippel-Feil
VACTERL