Surgery

Question 1

Biologic fixation recommended in:

Answer 1

maintain length and alignment Comminuted fracture fragments lag screw would result in fragment devitalization gap in fracture and a plate will be used to maintain the relative position of fragments

Question 2

Biologic fixation:

Answer 2

not stable, requires soft tissue attachments and blood supply of comminuted fragments union depends on bridging callus rather than primary bone union

Question 3

Biologic fixation technique:

Answer 3

1. reposition and realign fracture, preserve soft tissue 2. leave comminution fragments out of mechanical construct (pieces should have vascular supply)
2. biocompatible materials
3. minimum contact btwn bone and implant
4. limiting operative exposure when possible

Question 4

Perioperative adrenal suppression

Answer 4

short ACTH stim test: reliable assess adrenocortical function –>abnormal: supplemental periop glucocorticoid —>normal, risk for adrenal insufficiency (unexplained hypotension despite volume depletion): steroid dose consistent w/ injury continue steroid until stress response diminished (48 hrs)

Question 5

Supplemental glucocorticoid dose for foot surgeries

Answer 5

100mg methylprednisone pre-op severe disease or extensive procedure –> continue and taper after surgery

Question 6

Thompson Procedure

Answer 6

indicated in underlapping fifth toe Z-type incision dorsally over proximal phalanx + resection of 5th proximal phalanx + resection of fifth proximal phalanx + reefing of capsule to fill dead space + corrective closure Z incision

Question 7

Disuse osteopenia

Answer 7

transient periarticular osteopenia can be seen with ankle arthrodiastasis

Question 8

Ankle arthrodiastasis

Answer 8

the use of hinges along the malleolar axis of an external fixator are debatable

Question 9

Skin flap viability test

Answer 9

Fluorescein dye study most accurate predictor 18 hrs after injection

Question 10

surgical care of diabetic limb threatening infection should be addressed within ____ hours after admission.

Answer 10

6 over 6 hours related to higher risk of amputation proximal to ankle

Question 11

Aspirin prophylaxis

Answer 11

81-325 mg ASA as primary or secondary prophylaxis continue preoperatively, with the exception of intracranial, middle ear, posterior eye or intramedullary spine surgery and possibly in prostate surgery

Question 12

Stainless steel

Answer 12

Chromium (major) > nickel > molybdenum

Question 13

Advantages of diaphysis osteotomy for callus distraction

Answer 13

easier access, well defined osteotomy, easier manipulation of periosteum, less mechanical strength, less metabolic activity

Question 14

Advantages of metaphysis osteotomy for callus distraction

Answer 14

greater surface area –> greater stability and strength, increased vascularity and osteogenic potential more difficult to manipulate periosteum

Question 15

Nail bed lacerations can be replaced within ___ days

Answer 15

7 after 7 days, presence of granulation tissue and contracture

Question 16

Phases of distraction

Answer 16

1. initiation (osteotomy and fixator placement) 2. latency (5-10 days depending on location) 3. distraction (1mm in 24 hr in four incriments) 4. consolidation

Question 17

Digital fillet flaps cover an estimated ___

Answer 17

15.6 sq cm

Question 18

Wilson V-Y skin plasty disadvantage:

Answer 18

undercorrection deformity exceeds amount of skin advancement

Question 19

Indication for Jones suspension procedure

Answer 19

Transfer of EHL through head of 1st met medial to lateral Indications: flexible cavus foot, flexible plantarflexed first ray, prophylaxis when hallucal sesamoids are removed Won’t treat rigid deformity of hypermobile first ray

Question 20

Cerclage wire methods

Answer 20

Twist knot has the greatest resistance to failure increased wire diameter increased load to failure values

Question 21

Techniques for circular skin defect

Answer 21

O-T closure, O-Z closure, mercedes benz closure

Question 22

Ponsetti method

Answer 22

Cavus, Adductus, Varus, Equinus

Cavus: correct the pronation of forefoot in relation to hindfoot by supinating forefoot (which elevates 1st ray)

Adductus: by abducting midfoot in the transverse plane, midfoot abducted under the talus (apply counterpressure with thumb against talus)

Varus: will be corrected when foot is entirely abducted

Equinus: by dorsiflexion of foot by perc tenotomy of AT

Use toe to groin casts, not below the knee casts

Question 23

Fifth metatarsal fractures most common to least

Answer 23

Most common: avulsion fracture of 5th met base (51.2%)

Transverse shaft (16%)

Jones (13%)

Spiral oblique (11%)

Zone 3 (6%)

Question 24

Second Hit Phenomenon

Answer 24

sequential insults can lead to overwhelming physiologic reactions

Question 25

What obscures the view of the anterior and middle facet during subtalar joint arthroscopy?

Answer 25

interosseus talocalcaneal ligament

Question 26

Risk factors for EKG pre op

Answer 26

men over 40 and women over 50 with risk factor (CHF, IDDM, ischemic cardiac disease, CVD, CHF, creatinine > 2mg/dl)

Question 27

Indications for supramalleolar osteotomies

Answer 27

periarticular tibial deformity

malunion of ankle arthrodesis

subtalar deformity with concomittant ankle arthrosis

ankle osteoarthritis with concomittant valgus deformity

Question 28

Contra-indications for supramalleolar osteotomies

Answer 28

talar tilt over 10 degrees

end-stage degenerative changes of ankle joint

unmanagemeable hindfoot instability

neuropathic disorders

Question 29

Best surgical procedure for HAV in CP patient

Answer 29

1st MPJ fusion (McKeever)

Question 30

Bridle procedure

Answer 30

Tri-tendon anastomosis (TP, TA, PL)

for flexible equinus and equinovarus or flaccid foot

better dorsiflexion power found in McCall study

Procedure: TP passed through longitudinal incision in TA. PL is harvested, then passed subcutaneously to the TP and TA anastomosis and secured.

Question 31

Condrocyte survivability with fresh osteochondral allografts

Answer 31

90% after 14 days

70% after 28.5 days