OITE 2021 Flashcards
Age + location chondroblastoma
KIDS
Epiphysis (and pelvis, talus, calc)
Lytic
Curretage + bone graft bc can erode articular cartilage untreated
The majority of enchondromas are what Enneking stage?
Enchondroma is a benign lesion = E st 1
Enneking of benign tumors
St 1 = indolent
St 2 = active
St 3 = aggressive
Treat enchondroma
If symptomatic: curettage
Sarcoma screening vs myxoid liposarcoma screening tests
Sarcoma: MRI field, CT chest
- Met to lungs
Myxoid liposarc: “ “ + CT abd/pel
- Mets to abd and retroperitoneum
The dorsomedial cutaneous nerve is the terminal branch of what nerve? (inner big toe)
SPN (cross from P to A 5cm above the ankle joint)
Commonly cut during hallux valgus
What is the common deformity when nailing prox 1/3 tibia?
Where do you place the blocking screw to prevent this?
Valgus + apex anterior
Screw in lateral + posterior proximal segment
What are the resus parameters for early total care?
One of the following:
Lactate <4
pH > 7.25
Base excess > -5.5
WBC not included
3 soft CI for hip scope
Cystic bone changes on MRI
>45yo
BMI >24
Which position of tab retractor placement is most likely to increase risk of femoral nerve injury?
Generally thinking direct anterior approach for THA - fem n + ext iliac art
Inf-med retractors
And penetrating IP muscle
Safest = 12 o’clock
Which structure provides the most valgus stability in extension: dMCL, sMCL or POL?
POL - most valgus stability in ext and IR
dMCL - stab ant translation, min valgus restraint at 60deg flex (2ary valgus stabilizer, does its most in extension)
sMCL - 1ary valgus restraint in flexion and IR
What is Grisel syndrome?
- Ddx
- Best diagnostic tests
Kid
Recent URI/head neck surg
SCM spasm -> acute head tilt/rotation bc general lig laxity in kids (AA rotatory subluxation)
Painful!
Ddx: congenital muscular torticollis (not painful)
Get XR: open mouth odontoid - see asymmetric C1 lateral masses
CT = gold standard
Treat Sever disease
Calc apophysitis
- Stretching
- SLC
Orthotics no benefit
Treat Lyme in kids
<8 = amoxicillin
>8 = doxy
Compare ORIF vs TEA for distal humerus frx in elderly patients
TEA
- Faster in OR
- Better Mayo elbow scores
ORIF
- Higher reop
Same post op ROM
SNAC wrist treatment tree (4 procedures)
- Distal pole excision (take out part thats causing arthritis w/ radial styloid)
CI: arthritis, SL instability, midcarpal instability, midcarpal arthritis
2/3. (retain wrist motion)
Scaphoidectomy w/ 4 corner fusion (capitate, lunate, triquetrum, hamate aka ULNAR)
Soft CI: smoker
PRC
CI: arthritis @ capitate head - Wrist fusion
Gout
- RF
- Crystals
RF
- Purine rich diet
- Diuretics
- EtOH
- Obesity
Monosodium urate
Complication of P1 fractures
PIP flexion contracture
Bc apex volar deformity
- Prox frag flexes 2/2 lumbrical
- Distal frag extends 2/2 central slip
The bone becomes too short for the long extensor mechanism
RCL injury thumb
- Where does the lig tear
- Treat
Evenly distributed between prox/mid/distal ligament (vs UCL = distal)
Amenable to 1ary repair even when delayed
What is the intrinsic tightness test
MCP extended, see PIP flexion
If PIP flexion improves w/ MCP flexion, then you have intrinsic tightness
What is the treatment for intercarpal coalitions
Non-op 1st since generally incidental finding
Then fusion (not resection of coalition)
Mechanism TXA
Lysine analog
Binds lysine receptors on plasminogen
Blocks plasminogen -> plasmin (cannot breakdown clots)
What artery lives in the biciptial groove?
Ax art -> ant hum circhumflex -> arcuate
Arcuate = branch that runs up medial biceps groove
What is the innervation of the long vs short head biceps femoris
Short: CPN
Long: tibial n
What is the most common fracture for intimate partner violence
Nasal
What foot injury has high correlation with amputation?
Frx all 5 MT
Do OATs procedures in the patellofem and tibfem joints do the same?
NO - patellofem 2x failure rate
What is the structure involved in the avulsion fracture of a “wrist sprain”?
Dorsal triquetral avulsion fracture
- DRC
- Dorsal intercarpal ligament
RF for DRUJ instab w/ DR frx
Ulnar styloid base frx (not tip)
Open
Treat Kienbock disease
= AVN lunate
Early = radial shortening osteotomy, core decompression distal radius
Late + active = PRC
Late + inactive = capitate resurfacing implant arthroplasty
What is likely happening if you have a irreducible volar PIP dislocation?
P1 head through lateral band + central slip (can get caught too)
Closed reduction tightens these
Dorsal - volar plate or flexor tendons
Thumb tip flap coverage
<2cm volar advancement flap
>2cm FDMA
Can do a NV island flap up to 4cm
Dorsal thumb is FDMA all the way
What is happening with RA patients slowly lose the ability to extend their fingers
Progressive attritional rupture of extensor tendons
Starts ulnar (small finger)
As the wrist degenerates and falls into ulnar deviation, the subsequent tendons sublux ulnar and rupture over the ulnar head
Painless
Must resect ulnar head to treat + tendon transfers
How splint snapping ECU
Pronation + wrist ext + rad dev
For acute ECU subsheath rupture
If refractory to non-op, can do subsheath recon
Structure at risk with C1 lateral mass screws
Internal carotid art
Why place screws 10deg med trajectory
SPORT outcomes
Spinal stenosis - surg > nonop
What are the 3 parameters for corrective surgery in adult spinal deformity
What is the most common complication for adult spinal deformity surgery
- TK + LL + PI <45deg
- LL = PI (if mismatch, construct breaks)
PT<25deg
SVA<5cm - T1 pelvic angle <14deg
Pseudarthrosis»_space; PJK
What are risk factors for progression of infantile scoliosis?
Treat
Progression:
- Cobb >25deg
- RVAD 40deg
- Worsening curve
Trt: elongation derotation flexion cast
Genetics for tibial pseudarthrosis
NF1 chr 17 - spont mutation
What are the pulleys in the thumb
Trt congenital trigger thumb
A1 oblique A2 (no cruciates in thumb)
Stretching + obs
NO role CSI
Op release
What are the 3 diseases with radius deficiencies and how do you tell them apart
TAR - AR
- Thumb present
- Bilateral absent radii
Holt Oram - AD
- Cardiac defects
Fanconi anemia - AR
- Do chromosomal breakage test -> bone marrow transplant
What nerve can be injured during an inversion ankle sprain
SPN
What is the most reliable XR landmark for accurate reduction of the syndesmosis
Posterior overlap fib/tib on lateral XR
What is Freiberg’s disease / 2 risk factors
2nd MT head AVN - looks like flattening on XRs
RF
- Long 2nd MT head (transfer loading)
- GR contracture
What cytokines are elevated in pro-inflam conditions?
TNFa
IL 1B
NF kappa B
Atypical lipomatous tumor
- 2 tumor markers
- Problematic areas
- Treat
MDM2, CDK4
Problematic in the retroperitoneum
Trt: marginal resection (not wide excision since benign)
Treat sarcoma
Wide excision - need clear margins
Pre vs post op rads (just different complications)
EXCEPT rhabdomyosarcoma (chemo sensitive, no rads!, +/- surg)
For MTP fusion (hallux rigidus), where can you malposition the plate causing too much MTP dorsiflexion?
Too proximal!!
6mm proximal to ideal position = 8deg increased DF
Spring lig
- What is the main lig + origin/insertion
1 = supmed calc-navic lig = larger/more important arch stabilizer
O: sustentaculum
I: navicular
Inf cal-navic lig
O: between ant/mid calc facets
Treat interdigital neuroma
Resection is the only way!!!
CSI 2mo prior to RCR have been associated with:
High REVISION rate
Tendon doesn’t heal! NOT infection
Avoid 6mo before RCR
What skin suture pattern has best mean incision perfusion?
Running subcuticular
A p value cutoff of 0.05, this indicates that there is a 5% chance that….
A positive result is not valid
If power is 0.9 rather than 0.8, the change in the interpretation is….
Increased confidence if a negative value is found
Power = 1- type 2 error
T2 error = negative result when a true difference exists
0.9 power = 10% probability of T2 error
0.8 power = 20% probability of T2 error
Increase sample size to increase power
What is a significant change for the following during spine surgery:
- Sensory change
Sensory change 50%+
What is Parsonage Tuner syndrome
Acute brachial neuritis
Ex: acute onset shoulder pain, subsequent weakness
MRI: diffuse T2 signal change
Trt: obs only
Rate of NV injury w/ knee dislocation
Pop art 16%
Pern nerve 25%
Insall Salvati index vs Caton Deschamps
IS = Patellar tendon length : patellar length
Normal <1.2
CD = inf pat articular surface distance from plateau : pat articular surface length
Normal <1.3
Describe the 3 MCL bundles elbow
Ant = tight ext, 1ary valgus restraint
Post = tight flex, 2ary valgus restraint
Transverse doesn’t cross elbow joint so no stability
Test for non-continuous data (ordinal) between 2 groups
Mann Whitney
What is a Brodie abscess
Intraosseous abscess 2/2 chronic osteo
Usually tibia in kids
No fever
Trt: OR + abx - leave the defect, will fill in with bone over time
Inheritance of post axial polydactyly of foot (aka extra pinky toe)
AD
If well formed (with nail) - high penetrance
If small or tag like - reduced penetrance
What does a 2:1 ratio of Co:Cr mean in a THA setting
Indicates trunnion as ion source
Not modular neck-stem interface or bearing surface
What is the interval for direct anterior hip approach
2cm dis/lat to ASIS, over TFL muscle (lateral to sartorius)
LCFN at risk (L2/3 roots)
Which meniscus is:
More important to stability
More mobile
Med more impt to stability - more attached to capsule / MCL
Lat more more mobile
ALL insertion
Between Gerdy + fib head (Segond frx here)
Xs tibial IR
Anatomic landmark for radial n
4cm prox to triceps aponeurosis (more helpful in trauma perhaps)
Crosses posterior humerus 20cm prox med epicondyle / 14cm prox to lat epicondyle
Goal serum 25 vit D
32-250 ng/mL
RF that say you should treat FNF with SHS > cancellous screws
Females
High BMI
Displaced frx
Smokers
Have high rates revision surgery with screws - why do SHS
Trt osteosarc
Chemo + wide resection
Chemo: MTX, adriamycin, cisplatin (MAP)
Blocking screws for distal femur frx
Lateral + anterior in distal segment
What are the osteotomies of a PAO
Sup pub rami
Ilium
Post col
Ischium
Mayfield classification perilunate
1: SL lig disruption
2: lunocapitate disruption
3: LT lig disruption - carpus dislocates, lunate stays
4: lunate dislocates into carpal tunnel
Nerve roots for Erbs
C5-6
Watch for biceps function 6mo
SCFE blood vessel causing AVN
MFCa
From postmed of deep fem art
DMD inheritance
X recessive
What factor determines if a selective thoracic fusion will be successful for AIS
Apical vertebral translation ratio > 1.2
Ratio = distance between C7 plumb line to apex of thoracic curve / distance bet center sacral vertical line + apex lumbar curve
