trauma Flashcards
1
Q
innervation of subscapularis?
A
upper and lower subscapular nerves (derived from POSTERIOR cord of brachial plexus)
2
Q
innervation of biceps brachii?
A
-musculocutaneous nerve (derived from lateral cord)
3
Q
innervation of pectoralis major?
A
-medial and lateral pectoral nerves (derived from the medial and lateral cords, respectively)
4
Q
innervation of rhomboid major?
A
-dorsal scapular nerve (derived from the C5 nerve root)
5
Q
innervation of supraspinatus?
A
-suprascapular nerve (derived from upper trunk)
6
Q
necrotizing fasciitis
A
- delay in time of diagnosis associated w/ poor outcomes!
- most commonly polymicrobial infection, w/ group A B-hemolytic strep the most common bacteria
- tx: emergent aggressive debridement of all involved tissues and immediate empiric antibiotics covering aerobic, anaerobic, gram positive and gram negative bacteria
7
Q
pain in retrograde vs antegrade femoral nails?
A
retrograde: knee pain
antegrade: hip pain, abductor weakness, and heterotopic ossification of the abductors
- Tornetta et al: more problems of length and rotation using a retrograde nailing
8
Q
what % of the proximal radial head articulates w/ the proximal ulna?
A
- 75%
- remaining 25% is considered the “safe zone” and is important for placement of fixation
- nonarticulating portion of radial head consistently encompassed a 90 deg angle localized by palpation of the radial styloid and Lister’s tubercle
9
Q
during the saline injection load test to diagnose traumatic knee arthrotomies, how much saline needs to be injected to diagnose 99% of knee arthrotomies?
A
175mL
- note the clinical exam alone can NOT be relied on to detect traumatic arthrotomies alone
- an inferoeromedial injection location requires significantly less fluid than a superomedial injection location
10
Q
pathway of the axillary nerve within the brachial plexus
A
-C5-C6 nerve roots–> upper trunk–> posterior division–> posterior cord
11
Q
Quadrilateral space syndrome
A
- condition defined by axillary nerve, +/- posterior humeral circumflex artery compression in the quadrilateral space
- most commonly affects the dominant shoulder in overhead movement athletes or other throwing athletes
- exam may reveal weakness w/ the arm positioned in abduction and external rotation
- in long standing compression, there may also be atrophy of the teres minor and deltoid muscle
12
Q
course of the musculocutaneous nerve through the brachial plexus
A
-C5-C7 nerve roots–> upper/middle trunks–> anterior division–> lateral cord
13
Q
course of the suprascapular nerve through the brachial plexus
A
-C5-C6 nerve roots–> upper trunk
14
Q
course of the long thoracic nerve through the brachial plexus
A
-C5-C7 nerve roots
15
Q
course of the ulnar nerve through the brachial plexus
A
-C8-T1 nerve root–> lower trunk–> anterior division–> medial cord
16
Q
use of long lateral locking plate to treat tibia fracture has been associated w/ what complication?
A
superficial peroneal nerve injury
17
Q
most commonly recommended fixation for comminuted fractures of the olecranon?
A
Plate fixation
18
Q
indications for plate fixation of elbow fractures
A
- comminuted fractures of olecranon
- oblique fx’s distal to the midpoint of the trochlear notch
- fractures that involve the coronoid process
- fractures associated w/ Monteggia fracture-dislocations
19
Q
indication for tension band wiring in elbow fracture?
A
best indicated for simple transverse fractures through the midpoint of the trochlear notch
20
Q
terrible triad injury of elbow
A
- elbow dislocation (often associated w/ posterolateral dislocation or LCL injury)
- radial head fracture
- coronoid fracture
21
Q
what is the most common complication following operative fixation of terrible triad elbow injuries?
A
Loss of elbow range of motion
-this REQUIRES reoperation
22
Q
protocol of fixation for terrible triad injuries of elbow
A
- coronoid fracture ORIF (capsular repair)
- radial head fx ORIF or replacement
- LCL complex repair (isometric point is center of capitellum)
- reevaluation of stability; MCL repair or hinged fixator application
23
Q
at the elbow, the anterior bundle of the medial collateral ligament inserts at which site?
A
-anteromedial process of the coronoid (sublime tubercle)
24
Q
what is the FUNCTIONAL ROM of the elbow joint?
A
30-130
25
Name the 5 elementary and 5 associated acetabular fracture patterns
Elementary: posterior wall, posterior column, anterior wall, anterior column, transverse
Associated: associated both column, transverse + posterior wall, T shaped, anterior column or wall+ posterior hemitransverse, posterior column + posterior wall
26
Posterior wall acetabular fracture
- most common
| - "gull sign" on obturator oblique view
27
Posterior column acetabular fracture
- best seen on iliac oblique view
- check for injury to superior gluteal NV bundle
- ilioischial line disrupted on AP view
28
Anterior column acetabular fracture
-more common in elderly puts with fall from standing (anterior column + medial wall)
29
Transverse acetabular fracture
- axial CT shows anterior to posterior fracture line
| - only elementary fracture to involve both columns
30
What are factors associated w/ Hoffa fracture of distal femur?
- isolated lateral condyle fracture
| - open fracture
31
most common associated injury for LC type pelvic injuries?
Closed head injury
32
function of sacrospinous and sacrotuberous ligaments in pelvic floor as it relates to pelvic ring injuries?
Sacrospinous: resists ER
Sacrotuberous: resists shear and flexion
33
Posterior SI complex (posterior tension band)
- strongest ligaments in body
- more important than anterior structures for pelvic ring stability
- Anterior SI ligaments: resists ER after failure of pelvic floor and anterior structures
- Interosseous ligaments: resists AP translation
- Posterior SI ligament: resists cephalad-caudad displacement
- Iliolumbar: resists rotation and augments posterior SI ligaments
34
what should you look for on physical exam in pelvic ring injuries?
- position of rest of lower extremities
- leg length discrepancy
- scrotal, labial, or perineal hematoma
- flank hematoma
- lacerations of perineum
- degloving injuries (Morel-Lavallee lesion)
- rule out lumbosacral plexus injuries
- rectal exam (mandatory)
- urogenital exam
- vaginal exam (mandatory)
35
how do you know when Inlet view of pelvis is adequate?
when S1 overlaps S2 body
| -idial for visualizing AP translation of hemipelvis, IR or ER of hemipelvis, widening of SI joint, sacral ala impaction
36
how do you know when outlet view of pelvis is adequate?
when pubic symphysis overlies S2 body
-ideal for visualizing vertical translation of hemipelvis, flex/ext of hemipelvis, disruption of sacral foramina and location of sacral fx's
37
radiographic signs of instability in pelvic plain films?
- >5mm displacement of posterior SI complex
- presence of posterior sacral fx gap
- avulsion fx's (ischial spine, ischial tuberosity, sacrum, transverse process of 5th lumbar vertebrae)
38
Young-Burgess Classification
APC, LC, VS, Combined
39
APC 1
- symphysis widening <2.5cm
| - tx: non-op, protected WB
40
APC 2
- symphysis widening > 2.5cm, anterior SI joint diastasis, posterior SI ligaments intact, disruption of sacrospinous and sacrotuberous ligaments
- tx: anterior symphyseal plate or ex fix, +/- posterior fixation
41
APC 3
- disruption of anterior and posterior SI ligaments (SI dislocation), disruption of sacrospinous and sacrotuberous ligaments, APC 3 associated w/ vascular injury
- tx: anterior symphyseal multi-hole plate or ex-fix and posterior stabilization w/ SI screws or plate/screws
42
LC 1
- oblique or transverse ramus fx and ipsilateral anterior sacral ala compression fx
- tx: non-op, protected WB (complete, comminuted sacral component); WBAT (simple, incomplete sacral fx)
43
LC 2
- rami fx and ipsilateral posterior ilum fx dislocation (crescent fracture)
- tx: ORIF of ilium
44
LC 3
- ipsilateral LC and contralateral APC (windswept pelvis); common mechanism is rollover vehicle accident or peds vs auto
- tx: posterior stabilization w/ plate or SI screws as needed; percutaneous or open based on injury pattern and surgeon preference
45
Vertical shear pelvic ring injury
- posterior and superior directed force; associated w/ the highest risk of hypovolemic shock (63%); mortality rate up to 25%
- tx: posterior stabilization w/ plate or SI screws as needed; percutaneous or open based on injury pattern and surgeon preference
46
Absolute vs relative stability
absolute: alignment and compression across fx site resulting in no micromotion at physiological loads, primary bone healing via cutting cones, no callus
relative: some degree of motion exists at fx site which is reversible (elastic) allowing for mechanical stimulation of bone healing, secondary bone healing via callus
47
5 functions of a plate
Compression: compression at fx site utilizing oblique screw holes in plate and placing screws eccentrically, primary bone healing
Neutralization: used to "protect" lag screw fixation or another absolute stability construct
Buttress: creates a stable shoulder w/ intact bone to resist shear forces. Usually found in peri-articular fxs and results in primary bone healing
Tension band: converts distractive forces into compressive forces by its orientation, primary bone healing
Bridge: used to span an area of comminution and is a relative stability construct (overall length, alignment, and rotation needs to be restored)
48
modulus of elasticity
describes deformation of a material to a certain amount of force. It is the SLOPE OF THE STRESS-STRAIN CURVE. Stiffer materials (stainless steel) have a higher modulus of elasticity while more flexible materials (titanium) have a lower modulus of elasticity.
49
stages of fracture healing and how long each lasts
3 stages: inflammation, repair, and remodeling
inflammation: time of initial injury and fx hematoma formation to 2 wks
Repair: soft callus to hard callus, 2 wks
Remodeling: lasts between 4-12 wks as woven bone is replaced by trabecular bone
50
intramembranous ossification vs enchondral ossification in primary and secondary bone healing?
primary: intramembranous
secondary: enchondral
51
Primary causes of acute compartment syndrome
- Severe trauma associated w/ a fracture or vascular reperfusion of a limb
- prolonged compression on an area by a tourniquet, dressing, or even a pt's own body weight
- burns
- extravasation of IV fluid or contrast material
- exercise-induced compartment syndrome
52
how is compartment syndrome diagnosed?
- made entirely based on physical exam in an awake, cooperative patient
- primary finding is increasing pain (often out of proportion to exam and non-responsive to pain meds)
- pain w/ passive stretch (most sensitive)
- other signs include paresthesias, pallor, paralysis, pulselessness, and poikilothermia (late findings)
53
at what pressure does acute compartment syndrome exist?
generally agreed that absolute pressure exceeding 30mmHg or when pressure is within 30mmHg of DIASTOLIC blood pressure
54
can compartment syndrome exist in setting of an open fx?
Yes. The open wound may help decompress one compartment, but the other fascial compartments can still be affected
55
tx of acute compartment syndrome?
emergent surgical decompression OF ALL COMPARTMENTS of the limb (single or double incision in lower leg; anterolateral and posteromedial incisions). The skin wounds are then left open until they are closed or skin grafted at a later time
56
What is an important aspect of post-op care of a patient who has developed compartment syndrome?
if muscle ischemia and/or death has occurred, myoglobinuria may result. Hydration and monitoring of renal function (BUN and creatinine) should be performed
57
what is the proper initial management in compartment syndrome?
initially, all constrictive dressings should be loosened or removed. Then perform a full neurovascular exam. Many would advocate for fasciotomies if there is clinical concern for the diagnosis.
58
what are the compartments in the lower leg?
4 compartments: anterior, lateral, deep posterior, superficial posterior
59
what are the compartments in the forearm?
3 compartments: volar, dorsal, mobile wad
60
what are the compartments in the hand?
10 compartments: one for each of the four dorsal interossei, three for the volar interossei, and one each for the ADDuctor pollicis, thenar muscles, and hypothenar muscles
61
what are the compartments in the foot?
exact number is debated (as many as nine), but most would agree that there are four distinct compartments: an intrinsic, medial, central, and lateral compartment
62
What is the proper starting point for a trochanteric entry nail for femoral shaft fracture?
```
the proper starting point
for a trochanteric nail is just lateral
to the long axis of the femur. Depending
on the patient’s anatomy,
this can vary between just medial and just lateral
to the tip of the greater trochanter.
On the lateral view, the starting
point is colinear with the long axis of
the femur.
```
63
What is optimal tx for vertical shear (Pauwels 3) type femoral neck fractures in relatively young pts?
Sliding hip screw w/ side plate is superior to cannulated screw fixation (lower rates of nonunion)
64
What is the proper starting point for retrograde IM nail of femoral shaft fractures?
```
Proper technique includes an insertion site in the
intracondylar notch at the apex of the Blumensaat line, which is approximately 1 cm anterior to the
posterior cruciate ligament origin.
With this as the starting point, the
trajectory for nail insertion should be
colinear with the long axis of the femur
in both the anteroposterior and
lateral planes. At
least two distal interlocks should be
used to minimize the risk of secondary
telescoping of the nail into the
knee joint
```
65
what is the "spur sign" in acetabular fractures?
Best seen on obturator oblique view, It represents a spike of bone from the intact hemipelvis and no articular surface remains with the hemipelvis, which defines the associated both column fracture. The weight-bearing surface of the acetabulum is displaced with the femoral head. In all other patterns, at least part of the articular surface remains with the intact hemipelvis.
66
what is the most important structure for preventing AP displacement of the sternoclavicular joint?
Posterior sternoclavicular joint capsule
67
Is IMN an example of absolute or relative stability?
Relative stability
68
what is the most important factor in achieving a satisfactory outcome following surgery for an ankle fracture?
anatomic alignment (quality of the reduction)
69
what additional imaging study is recommended for a spiral distal third tibia fracture besides tib/fib plain films?
CT scan of ankle;
Spiral distal tibia fractures are frequently associated with intra-articular fracture extension, usually involving the posterior malleolus. This may or may not be visible on the radiographs. A CT scan of the ankle is recommended to identify this associated injury. This is especially important when considering intramedullary nail fixation of the distal tibia fracture because a previously nondisplaced intra-articular fracture may become displaced as the nail is inserted to its final depth. Anteroposterior screw fixation prior to nailing may be useful in these cases
70
what is the most common complication following surgery for a "terrible triad" elbow fracture-dislocation?
Restricted elbow ROM is almost always present
71
what are factors that are predictive of osteonecrosis of the humeral head after fracture?
Factors shown to be predictive of osteonecrosis include: fractures consisting of four fragments, angular displacement of the head (greater than 45 degrees ), the amount of displacement of the tuberosities (displacement of greater than 10 mm), glenohumeral dislocation, and head-split components. Factors associated with good prognosis include: length of the metaphyseal head extension (calcar segments of greater than 8 mm), the integrity of the medial hinge, and the basic fracture pattern. When the above criteria (anatomic neck, short calcar, disrupted hinge) were combined, positive predictive values of up to 97% could be obtained for osteonecrosis. However, the degree to which this osteonecrosis impacts long-term outcome is unclear and should not be the only indication for proximal humeral arthroplasty.
72
How often is acute carpal tunnel seen after distal radius fractures?
5-8%
73
Acceptable criteria for non-op treatment of diaphyseal humerus fractures?
- < 20 deg AP angulation
- < 30 deg varus/valgus angulation
- < 3cm shortening
Note that proximal 1/3rd long oblique fx's are at greatest risk for nonunion after functional bracing. Also, radial nerve palsy is NOT a contraindication to functional bracing.
74
how do you treat an adult both bone forearm fx in almost all cases, regardless of angulation?
ORIF of both the radius and ulna
75
plate fixation of clavicle fx's compared to non-op tx?
- lower nonunion rate
- higher cost
- higher rate of implant-related complications and subsequent surgery
76
what is the most cost-effective management strategy for clavicle fractures?
non-op tx w/ delayed surgery in the setting of nonunion
77
how do you managed supracondylar fx w/ pink pulseless hand before and after CRPP?
splinting and observation in the hospital
78
management of displaced supracondylar fx w/ absent pulse
- adequate perfusion?--> reduce fx and pin, observe if cap refil, temp, and color indicated adequate perfusion--> admission for vascular obs w/ elbow in relaxed position of approx 45 deg
- pulseless extremity, inadequate perfusion?--> reduce fx and pin--> if hand is pink and pulseless, then admit for vascular obs as above; if hand remains dysvascular, then explore and repair artery via anterior approach (monitor for compartment syndrome, consider fasciotomy)
79
how do you manage an acute posterior SC dislocation?
attempt closed reduction in the OR w/ vascular surgery on back-up
80
most common site of comminution in a high energy femoral neck fx in young adult?
Posterior and Inferior
81
what factor is most important in regard to treating young adult femoral neck fxs?
quality of reduction (largest impact on fx healing and clinical outcomes)
82
2 most common approaches to ORIF of femoral neck fracture?
- Watson-Jones (anterolateral approach to hip)
| - Heuter (distal limb of smith-peterson anterior approach to hip)
83
Necrotizing fasciitis
- Sx: red or purple skin w/ severe pain, fever, and vomiting
- Dx: surgical exploration in setting of high suspicion; may also use LRINEC score (CRP, WBC, Hgb, Na, Cr, glucose)
- Most common organism is POLYMICROBIAL INFECTION (though group A strep is most common in monomicrobial nec fasc)
- often associated w/ diabetes
84
5 indications for surgical intervention of tibial plateau fx?
- > 3mm articular step off
- > 5mm condylar widening
- > 10 deg var/valg laxity
- any medial plateau component
- bicondylar fx's
85
when should you obtain advanced imaging of a significantly displaced bicondylar tibial plateau fx?
Probably after application of a knee-spanning ex-fix. This allows for ligamentotaxis to reduce the fx fragments and allow for better delination on CT imaging
86
non-op indications for distal humerus fx's?
non-displaced Milch Type 1 fx's (immobilize in supination for lateral condyle fx's, and pronation for medial condyle fx's)
87
how to treat ligamentous Lisfranc injuries?
Open reduction and ARTHRODESIS of the medial 2 tarsometatarsal joints (equivalent functional outcomes and decreased rate of hardware removal or revision surgery compared to primary ORIF)
88
how to treat bony Lisfranc injuries?
most often ORIF is any evidence of instablity (>2mm shift)
89
Non-op indications for Lisfranc injuries
-no displacement on WB and stress radiographs and no evidence of bony injury on CT
90
5 critical radiographic signs to look for with suspicion of Lisfranc injury
- disruption of line from medial base of second metatarsal to medial side of middle cuneiform
- widening of interval between first and second ray
- medial side of base of fourth metatarsal does not line up w/ medial side of cuboid on OBLIQUE VIEW
- metatarsal base dorsal subluxation on LATERAL VIEW
- disruption of the medial column line (line tangential to medial aspect of the navicular and the medial cuneiform)
91
Ideal starting position for a tibial IMN?
- medial upslope of lateral tibial spine
| - anterior lip just anterior to articular surface on lateral view
92
criteria for septic shock
sepsis w/ persisting hypotension requiring vasopressors to maintain MAP > 65 mmHg and having serum lactate > 2mmol/L despite adequate volume resuscitation
93
how to assess syndesmotic instability after ORIF ankle fx?
-assess either through open visualization or by comparing closed reduction parameters (clear space, overlap, and fibular position on lateral view) w/ the patient's contralateral side (assuming no injury)
94
what is the most biomechanically stable method of fixation for vertically oriented (eg Pauwels III) femoral neck fx's?
Sliding hip screw and side plate (+/- antirotation screws)
95
Triplane fractures in peds
- complex fx pattern that crosses the distal tibial physis in 3 different planes
- on lateral view, fx appears to be a SH II w/ a posterior metaphyseal component
- on AP view, fx appears to be a SH III w/ fx line exiting the ankle joint
96
Distal tibial physis order of ossification
central > posterior > medial > anterolateral
| -Important when thinking about mechanism in Triplane and Tillaux fx's (transitional fxs)
97
Tillaux fx
- SH III fx of distal tibia epiphysis
- caused by avulsion of anterior inferior tibiofibular ligament
- Transitional fx (similar to Triplane fx's, but typically occur in older age group)
- lack of fx in the posterior distal tibial metaphysis in the coronal place distinguishes this from a triplane fx
- often associated w/ ER deformity and mechanism
- occur in older children at the end of growth
98
how do you position a patient for surgery w/ a posterior partial articular tibial plateau fx?
- PRONE
- look for signs of posterior fx on lateral x-ray, obtain CT
- usually incorporate a posteromedial interval deep to the popliteus and soleus to provide buttress plating to posterior column of tibia
99
Is ulnar nerve transposition beneficial for ORIF of distal humerus fxs?
NO
| -it INCREASES (4x) ulnar neuritis
100
"classically" acceptable criteria for closed reduction of peds distal radius/ulna fractures?
- < 9 yrs: 30 deg dorsal angulation
| - > 9 yrs: 20 deg dorsal angulation
101
"classically" acceptable criteria for closed reduction of peds shaft/both bone forearm fxs?
- < 9 yrs: < 1 cm bayonetting, 15-20 deg angulation, 45 deg malrotation (controversial)
- > 9 yrs: < 1 cm bayonetting, 10 deg angulation, 30 deg malrotation (controversial)
102
optimal method of treating peds distal radius fx if unacceptable alignment after failure of closed reduction?
- closed reduction and percutaneous pinning (most often) for SH 1 or SH 2 fx
- ORIF for displaced SH 3 or SH 4 fractures (still typically utilize PINS and NOT PLATES)
103
what is the most common complication after patellar fracture ORIF?
symptomatic hardware (up to 50% require removal)
104
rate of ipsilateral femoral neck and femoral shaft fractures, and how to avoid missing them?
- up to 6%
| - get thin cut pelvic CT images w/ coronal and sagittal reconstructions
105
what is the optimal position of the clamp for syndesmosis reduction in ankle fractures?
-At the syndesmosis level with the midmedial tibia and fibular ridge, w/ reduction and fixation of the posterior malleolus
106
when comparing IMN to plating for distal tibia metaphyseal fxs, IMN is associated with what?
- less surgical time
- less radiation
- less difficult hardware removal
107
what is the advantage of submuscular plating compared with extensile lateral approach for periprosthetic supracondylar femur fxs?
Decreased risk for nonunion s/t less periosteal stripping
108
terrible triad of elbow
- radial head/neck fx, coronoid tip fx, elbow dislocation
- most often result of VALGUS POSTEROLATERAL instability (comminuted radial head fx and small coronoid tip fx)
- some may have varus posteromedial pattern (intact radial head and large anteromedial coronoid facet fx)
109
Describe the 2 lateral approaches to the elbow
-Kaplan and Kocher
-Kaplan: more anterior, between ECRB and EDC, or alternatively EDC split. Avoids injury to LUCL, but puts PIN at risk.
-Kocher: more posterior,
internervous between ECU (PIN) and anconeus (radial)
110
what inserts on the sublime tubercle of the elbow?
anterior band of MCL
111
Best way to minimize K-wire migration after tension band fixation of patella fractures?
-Bend the wires proximally AND distally
112
what are the risk factors for distal femur fx locked plate fixation failure?
- open fx
- diabetes
- smoking
- increased BMI
- shorter plate length
113
what is the most common complication of nonsurgical tx of displaced midshaft clavicle fx's?
Nonunion (~15%)
| -risk factors for nonunion: female gender, displacement exceeding 100%, comminution, advanced age, smoking, comminution
114
what is the greatest benefit of ex-fix for displaced and unstable pelvic ring injuries w/ hemodynamic instability?
- It helps maintain a stable clot over injured vessels
| - initial clot contains more clotting factors than blood after volume resuscitation
115
what is the mechanism of action of negative pressure wound therapy (wound vacs)?
-Increased blood flow to the wound by way of stabilizing wound bed environment, increasing angiogenesis as a byproduct
116
most common complication of wound vacs?
-rash on the skin resulting from contact with suction sponge
117
what are the simple and associated types of acetabular fx's in Letournel classification?
```
10 total
Simple:
-posterior wall (most common)
-posterior column
-anterior wall
-anterior column
-Transverse (involves both AC and PC)
```
Associated:
- Posterior column/posterior wall
- transverse/posterior wall
- T-type (transverse w/ vertical limbs through ischium)
- anterior column/posterior hemitransverse (lest common type)
- associated both column (most common associated type; "spur sign")
118
Spur sign in acetabular fx's
- seen with associated both column fxs
| - seen on obturator oblique view, represents undisplaced posterior ilium
119
Hallmarks of sacral dysmorphism
- prominent mammillary processes
- anterosuperior deficiency of sacral ala
- iliac crest at same level as upper sacral border on outlet view
- downsloping sacral ala
- vestigial S1 disc remnant
- irregular tongue and groove contour of SI joint
120
six cardinal lines of acetabulum on radiographs
- Posterior wall
- anterior wall
- dome
- teardrop
- Ilioischial
- Iliopectineal
121
how do you systematic review radiographs for acetabular fx classification?
examine iliopectineal and ilioischial lines:
-If both lines intact, then its PW fx
-if only one line disrupted (Iliopectineal--> anterior wall or anterior column fx)
(Ilioischial--> posterior column or posterior column and PW fx)
-If both lines disrupted, then look at obturator ring and determine if its intact (ring intact--> transverse or transverse/PW) (ring disrupted-->look at iliac wing. If iliac wing intact, then its T-type. If iliac wing disrupted, then its anterior column-posterior hemitransverse or associated both column fx)
122
corona mortis
- vascular communication between EXTERNAL ILIAC and OBTURATOR ARTERY
- typically seen about 5cm medially from pubic symphysis
- needs to be ligated to prevent retraction of inadvertently injured vessel
123
PICPOW
Iliac oblique: posterior column and anterior wall (looking at ilioischial line)
Obturator oblique: posterior wall and anterior column (looking at iliopectineal line)
124
3 general surgical approaches to acetabular fx
- Kocher langenbeck (posterior)
- Ilioinguinal (anterior; includes modified Stoppa to visualize quadrilateral surface)
- extended iliofemoral
125
Heterotopic ossification in acetabular surgical approaches
- highest in extended iliofemoral approach, lowest in anterior approach
- prophylaxis w/ indomethacin or 600cGy radiation within 48 hrs of surgery
126
where do you typically place a transiliac transsacral screw in pts w/ sacral dysmorphism?
-S2 osseous corridor
127
retrograde flexible IMN vs antegrade reamed locked IMN for peds and adolescent femoral shaft fx's
- retrograde IMN provide less rigid fixation and are associated w/ higher rates of angular malunion, rotational malunion, and shortening through the fx site, esp for big kids and length unstable fxs
- antegrade locked nails may damage the lateral epiphyseal vessels of femoral neck and cause AVN; they should be started on the lateral greater troch rather than piriformis fossa; premature arrest of the GT physis can lead to coxa valga in younger children
128
proximal tibia fxs tend to fall into VALGUS and PROCURVATUM. How does this effect where you place blocking screws?
-blocking screws should be placed at the CONCAVITY OF THE DEFORMITY and where you DON'T want the nail to go. In this case, lateral and posterior, both PROXIMAL to the fracture line
129
difference between long vs short IMN in intertroch fxs?
Implant cost is the only statistically reported difference in the literature
130
how does intra-op compartment pressure measurement effect your treatment decisions in regard to fasciotomies for compartment syndrome?
-pts under anesthesia will have lower SBP/DBP relative to their pre- and post-op measurements. Therefore, if you check a compartment pressure intra-op, you should use their PRE-OP diastolic BP as your reference for when to perform fasciotomies, NOT their intra-op pressures
131
wound vacs work by what mechanism?
- they increase wound perfusion and stabilize wound bed environment
- help to PREVENT wound contracture, can help to improve tissue EDEMA
- specialized white polyvinyl alcohol sponges are available to prevent adherence to vessels, exposed nerves, or exposed bone
- NPWT should NOT be used directly over exposed major vessels
- Hemorrhage is the most common MAJOR complication associated w/ NPWT, skin irritation is the most common MINOR complication
132
locked plate fixation of distal femoral fxs may result in a medial translation of the distal femur when the plate is placed too...?
- POSTERIOR DISTALLY
- "golf club" deformity results
- occurs because posterior part of lateral condyle projects more laterally than the desired footprint of the lateral condyle. Also, this will lead to placement of screws in the intercondylar notch, injury to cruciates, and loss of knee ROM
- anterior placement of the plate proximally in the shaft will lead to inadequate fixation in view of unicortical fixation.
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what is the most reliable predictor of a fragility fracture?
hx of previous fragility fracture
134
use of long term bisphosponates is associated with what?
- increased risk for atypical femur fxs
- decreased risk for fragility fractures overall
- some reports of osteonecrosis of the mandible with prolonged use
- current literature suggests stopping these drugs after 3-5 yrs to allow bone remodeling
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strategies to improve construct for ORIF of proximal humerus fx?
- restoring medial cortical support (medial calcar)
- incorporating rotator cuff into construct
- placement of screws of adequate length to gain purchase in subchondral bone of humeral head
136
Timing of femoral shaft fx fixation in pts w/ head injuries?
1. Apply ‘‘early total care’’ by femoral intramedullary nailing
in all patients with mild TBI, GCS of 14 or 15 points, and
normal craniocerebral CT scan (if available), unless
intramedullary nailing is contraindicated for other reasons (eg, severe chest injury, traumatic–hemorrhagic shock, and
so on)
2. Apply a ‘‘damage control’’ procedure by external femur
fixation in all patients with severe TBI either defined by
a GCS 8 points or less (comatose patients) and/or the presence of significant intracranial pathology on CT scan (edema, midline shift, sub-/epidural bleeding, open head injury with intracranial air)
3. Consider a ‘‘damage control’’ procedure by external femur fixation in all patients with moderate TBI either with a GCS of 9 to 13 points or in the presence of ‘‘minor’’ intracranial pathology on CT scan (eg, traumatic subarachnoid bleeding) in patients with GCS of 14 or 15
4. Consider conversion from external to internal fixation in
patients with TBI who recovered from a comatose state and are awake and alert (GCS greater than 12) or comatose patients with a stable ICP (less than 20 mmHg) and CPP (greater than 80 mmHg) for more than 48 hours.
137
Induced membrane technique for bone defects
- involves placement of a PMMA cement spacer into a bony defect w/ skeletal stabilization of the defect
- in a staged fashion, typically 6-8 wks later, a robust membrane forms around the cement spacer
- the membrane is incised, the spacer removed, and the void is filled w/ bone graft. the membrane helps act as a place holder for the bone graft and helps contain the graft and limit resorption. It also has growth factors (VEGF, TGF-b, and BMP-2) that help promote bone healing
138
high energy tibial plateau fx's (Schatzker IV or greater) require ABIs in the ED
.
139
most common acetabular fx type in elderly osteoporotic pts w/ low-energy mechanism?
Anterior column and "medial wall" (due to landing on greater trochanter
140
what is the best surgical approach for a capitellar shear fracture of the distal humerus?
-Lateral column, elevating off of common extensors and the capsule
141
In general, all cases of extruded talus should undergo reimplantation
.
142
Know the difference between osteoinductive, osteoconductive, and osteogenic!
- osteoconductive requries structure to act as scaffolding
- bone graft with BMP is osteoinductive because it induces bone cell differentiation
- osteogenic substances have intrinsic bone forming material within it?
143
how to determine syndesmotic instability intra-op
Syndesmotic instability should be assessed with direct manipulation on both the anteroposterior and lateral views with special attention to the lateral view. Syndesmotic reduction should be assessed either through open visualization or by comparing closed reduction parameters (clear space, overlap, and fibular position on the lateral view) with the patient’s contralateral side (assuming no injury). This is more effective than using population norms secondary to the two types of syndesmotic morphologies which create different absolute values for these parameters.
144
which is more common in pts w/ non-op tx of displaced midshaft clavicle fxs; symptomatic malunion or nonunion?
-NONUNION (about 15% vs about 9% of symptomatic malunion)
145
what are risk factors for failure of locked plate fixation of distal femoral fxs?
```
open fxs
diabetes
smoking
increased BMI
shorter plate length
```
146
what is more common in displaced femoral neck fxs undergoing percutaneous fixation; nonunion or malunion?
-NONUNION (varus) is more common than malunion
147
Most important and strongest ligament in Lisfranc injuries?
oblique INTEROSSEOUS ligament (dorsal ligaments are weakest and may be first to fail)
148
radiographic evaluation of Lisfranc injuries
- second MT base should be aligned w/ the middle cuneiform at the medial borders on AP view
- fourth MT base should be aligned w/ the cuboid at the medial borders on oblique view
- dorsal and plantar aspects of the MTs should align w/ the cuneiforms/cuboid on the lateral view
- diastasis between the second MT and the first MT/medial cuneiform complex of more than 2mm indicates injury, as does TMT joint subluxation of 2mm more than seen on uninjured contralateral side (although diastasis between the first and second MT up to 2.7mm can be normal)
- avulsion fx of the second MT base or medial cuneiform
- may obtain WB radiographs/CT/MRI to further characterize injury
149
septic shock
-sepsis w/ persisting hypotension requiring vasopressors to maintain MAP > 65mmHg and having serum lactate level > 2mmol/L despite adequate volume resuscitation
150
what is the optimal tip-apex distance when placing DHS for intertroch femur fxs?
< 25mm
151
interval for posterolateral approach to ankle
FHL and peroneus longus (often used for posterior malleolus fx fixation)
152
anterior approach to ankle
anterior tibial tendon and EHL
153
anterolateral approach to ankle
peroneus brevis and peroneus tertius (often used in tx of pilon fxs)
154
posteromedial approach to ankle
-neurovascular bundle lies in the interval between the FHL and flexor digitorum longus
155
what is the best treatment option for complex humerus fxs in the low demand pt population?
Non-op treatment
| -Mao et al--> no evidence to support use of any operative modality to treat 3 or 4 part fxs in low demand pts
156
acceptable dorsal angulation in pediatric distal radius/ulna fxs?
- < 9 yrs--> 30 deg
- > 9 yrs--> 20 deg
- if radial/ulnar SHAFT fx, then the tolerances are half of those listed above
157
main source of blood supply to femoral head in adults
deep branch of medial femoral circumflex artery
-lateral femoral circumflex artery, artery of ligamentum teres, and inferior gluteal artery have minimal contribution as well
158
what do studies show on evaluating effectiveness of comanagement protocols for tx of hip fx in pts older than 60?
- significant improvements in mortality, length of stay, complication and readmission rates, and ambulatory status at time of discharge while decreasing costs
- Note that surgical time, blood loss, time to surgery, and INPATIENT mortality have NOT been altered
159
Radial nerve palsy associated w/ high-energy humeral shaft fxs?
Transection of the radial nerve (neurotmesis) is usually associated with open fractures of the humerus that are part of a very complex upper-extremity injury. The results of primary nerve repair in this circumstance are poor, likely related to an extensive zone of injury and the need for nerve grafting. Intact nerves and nerve palsies that are part of a closed fracture nearly always recover, even after high-energy injuries. Because the first signs of nerve recovery and complete recovery of the nerve can be quite delayed, patience is merited before considering tendon transfers.
-Although radial nerve palsy associated with a closed humeral shaft fracture may be managed by observation, it is our experience that an open humeral shaft fracture with radial nerve palsy requires exploration of the nerve. In a series of 14 patients with radial nerve palsy caused by an open humeral shaft fracture, 9 (64%) of the 14 patients had a radial nerve that was either lacerated or interposed between the fracture fragments. There was an equal incidence of radial nerve lacerations or entrapments in types I, II, and III open humeral shaft fractures.
160
How should complex pilon fxs be managed?
immediate (within twenty-four hours) open reduction and internal fixation of the fibula when fractured, using a one-third tubular or 3.5-millimeter dynamic compression plate and application of an external fixator spanning the ankle joint. Patients with isolated injuries were discharged after initial stabilization and readmitted for the definitive reconstruction. Polytrauma patients remained hospitalized and were observed. Formal open reconstruction of the articular surface by plating was performed when soft tissue swelling had subsided
161
risk of AVN of talar body after type III talar neck fx-dislocations?
AVN of the talar body after Hawkins type III talar neck fracture dislocations occurs 40% to 90% of the time. Hawkins sign type provides fair to good positive predictive value that indicates revascularization of the talar body is occurring, but the anterolateral portion of the talar dome can develop osteonecrosis even when the remaining body is well vascularized. The Hawkins sign usually is seen at 6 to 8 weeks after surgery as a subchondral lucency underlying the talar dome.
162
Hawkins classification of talar neck fxs?
- Hawkins I: nondisplaced (AVN 0-13%)
- Hawkins II: subtalar dislocation (AVN 20-50%)
- Hawkins III: subtalar and tibiotalar dislocation ( AVN 20-100%)
- Hawkins IV: subtalar, tibiotalar, and talonavicular dislocation (AVN 70-100%)
163
starting point for tibial nail on AP x-rays?
in line w/ the medial border of the lateral tibial eminence (just anterior and adjacent to articular surface on lateral x-rays)
-remember you MUST HAVE a true AP and lateral of the knee because appearance on fluoro can vary widely when evaluating starting point if true AP not obtained!
164
spinal cord syndrome w/ best chance of recovery?
Brown-sequard syndrome
165
spinal cord syndrome w/ worst change of recovery?
Anterior cord syndrome
166
most common spinal cord syndrome?
central cord syndrome
167
"fleck sign" on ankle radiographs?
- avulsion of the posterior distal fibular ridge, which represents an injury to the superior peroneal retinaculum and probable peroneal dislocation
- initial management of acute injuries w/ cast immobilization in plantar flexion/inversion w/ use of a pad in the shape of a "U" or "J" is effective in 50% of pts, the rest will require surgery
168
what is the most common complication after use of an anterior sub q internal fixator in surgical tx of unstable pelvic fx?
Heterotopic ossification (typically asymptomatic)
169
special considerations for diabetics w/ ankle fxs?
- if evidence of diabetic neuropathy on monofilament testing, enhanced fixation w/ syndesmotic screws has been advocated in the setting of displaced fxs without syndesmotic injury; prolonged periods of NWB and protection are also preferred
- general rule of thumb: double the fixation and double the period of NWB compared to non-diabetics
170
which nerve is most likely to exhibit the worst functional recovery after repair of a gunshot wound?
Ulnar nerve
- nerves with the worst recovery rate after GSW are the peroneal nerve, ulnar nerve, and brachial plexus lesions
- nerves with the best recovery rate after GSW are the tibial, median, and femoral
171
what does posterior malleolar stabilization accomplish in complex ankle fxs?
- restores incisura competence thereby reducing the incidence of syndesmotic malreduction by creating containment
- assists in stabilizing the syndesmosis via the posterior inferior tibiofibular ligament, potentially limiting the need for additional syndesmotic stabilization
- maximizes the surface area for ankle joint loading
- enhances posterior translational stability of the talus
172
3 primary types of posterior malleolus fx patterns?
- posterolateral oblique
- medial extension
- shell
173
which radiographic view is most important in assessing syndesmotic reduction?
- LATERAL VIEW
- assess syndesmotic stability after all other points of instability are fixed!
- compare clear space, overlap, and fibular position on lateral view compared to pt's contralateral uninjured side
174
Ideal plate length for locking plate fixation of supracondylar distal femur fxs?
- a plate longer than 9 holes (shaft) that allows for at least 8 holes proximal to the fx is ideal
- other risk factors for implant failure besides short plate are obesity, open fxs, smoking, and younger age
175
when does "golf club deformity" of distal femur occur after ORIF of supracondylar femur fx?
when plate is placed too distal and posterior
176
which nerve crosses your surgical field during anterolateral approach to ankle?
Superficial peroneal nerve
177
Kaplan vs Kocher approach to elbow
- Kaplan is more ANTERIOR, between ECRB and EDC (or possibly EDC split); avoids iatrogenic injury to LUCL, but brings PIN closer to dissection
- Kocher is more POSTERIOR, between ECU and anconeus; internervous plane between radial nerve (anconeus) and PIN (ECU)
178
suprapatellar IMN for tibia fxs when compared to infrapatellar nailing is associated with...?
- less anterior knee pain in 1 study
| - Sanders et al, JOT 2014, prospective study; 0 of 55 pts complained of anterior knee pain
179
best approach to treating femoral shaft nonunions after IMN
- corrective alignment and compression plating without a bone graft
- Modern plating techniques are effective in the treatment of femoral shaft nonunions after intramedullary fracture fixation. The authors consider this method particularly valuable in the presence of deformity. Union occurred reliably with few complications.
- Bellabarba et al, JOT, 2001
180
how does timing of ORIF for tibial plateau fxs after fasciotomy influence infection risk?
- Timing does not influence infection risk
- This study demonstrated no statistical difference in the rate of infection when tibial plateau fractures with four-compartment fasciotomies were treated with open reduction and internal fixation before fasciotomy closure, at fasciotomy closure, or after fasciotomy closure. Based on the data presented herein, it seems that definitive fracture treatment can be determined by the condition of patient and by surgeon preference and experience without exposing the patient to the additional risk of infection.
- Zura et al, J Trauma, 2010
181
Does the time of post-op bisphosphonate administration affect bone union in osteoporotic intertroch femur fxs?
No, the initiating time of bisphosphonate administration following surgery does not affect the clinical outcomes in pts w/ osteoporotic intertroch fxs
182
strongest risk factors for clavicle fx nonunion?
- smoking
- comminution
- fx displacement
183
Remember that nonunion is UNCOMMON after surgical tx of clavicle fxs, but COMMON (15%) after non-op tx
.
184
what injury pattern is typical of varus posteromedial rotatory instability?
- large medial coronoid fx
- elbow dislocation
- intact radial head
185
how to fix large medial coronoid fx?
- Surgical approaches to coronoid fx's depend on the condition of the radial head
- When an associated radial head fracture is present, a lateral approach to the coronoid fracture is often performed. An isolated coronal fracture is typically approached from the medial side. Intraoperative stress testing may be helpful in assessing the need for surgery and choosing the surgical approach.
- If radial head intact, either FCU split approach or medial Hotchkiss over-the-top approach, then buttress plating
186
best treatment for hypertrophic nonunion of tibia
exchange nailing
187
strategies to prevent construct failure in ORIF of proximal humerus?
- restoration of medial cortical support (medial calcar)
- incorporation of RTC into construct
- placement of screws of adequate length to gain purchase in subchondral bone of humeral head
188
nonsurgical tx of geriatric type II odontoid fxs can lead to?
- increased mortality rates
- Multiple studies demonstrate decreased mortality after geriatric patients sustain type II odontoid fractures if they are treated surgically. The 1-year mortality rate for patients treated surgically is about 14%, but this rate is about 26% for patients treated nonsurgically.
189
antibiotic coverage for open fxs?
- Gustilo I and II --> 1st gen cephalosporin (cefazolin)
- Gustilo III --> 1st gen cephalosporin and aminoglycoside (cefazolin and gentamicin) or a fluroquinolone; PCN is commonly added in barnyard injuries for extended coverage of soil-borne pathogens (clostridial species); add doxycycline (tetracycline) for brackish water injuries
190
preferred procedure for tx of significant bone and soft tissue loss?
Vascularized fibular graft w/ associated skin flap
| -avoid large quantities of allograft in setting of open fxs w/ soft tissue compromise s/t risk of infection
191
management of distal biceps rupture?
Rupture of the distal biceps tendon accounts for 10% of all biceps brachii ruptures. Injuries typically occur in the dominant elbow of men aged 40 to 49 years during eccentric contraction of the biceps. Degenerative changes, decreased vascularity, and tendon impingement may precede rupture. Although nonsurgical management is an option, healthy, active persons with distal biceps tendon ruptures benefit from early surgical repair, gaining improved strength in forearm supination and, to a lesser degree, elbow flexion. Biomechanical studies have tested the strength and displacement of various repairs; the suspensory cortical button technique exhibits maximum peak load to failure in vitro, and suture anchor and interosseous screw techniques yield the least displacement. Surgical complications include sensory and motor neurapraxia, infection, and heterotopic ossification. Current trends in postoperative rehabilitation include an early return to motion and to activities of daily living.
192
when compared to plate fixation of distal metaphyseal tibia fxs, IMN results in...?
- higher rate of malalignment
| - similar rates of soft-tissue breakdown, deep infection, and nonunion
193
what is the main difference between Gustilo IIIa and IIIb tibial fx's?
-need for free tissue transfer
194
Posterior wall acetabular fractures of intermediate size that do not render the hip joint unstable can be treated nonsurgically with the expectation of a good result. The most effective way to determine hip stability is stress examination EUA. If the hip joint is unstable at the time of EUA, ORIF should be performed to provide the best outcome. A hip dislocation is not predictive of hip instability at the time of EUA. Experts in acetabular fracture care cannot reliably predict hip stability in intermediate-sized posterior wall acetabular fractures.
.
195
place blocking screws (Poller and cortical substitution screws) in the CONCAVITY OF THE DEFORMITY and where you DON'T WANT THE NAIL TO GO. They can be helpful in treating metaphyseal fx's w/ IMN.
.
196
According to the 2011 AAOS Guideline on the Treatment of Pediatric Supracondylar Humerus Fractures, immediate closed reduction of displaced fractures should be performed in patients with decreased perfusion of the hand. The most likely cause of decreased perfusion is compression of the brachial artery, and closed reduction should be attempted to alleviate compression. Immediately following reduction, a repeat perfusion assessment should be performed to determine improvement. If there is no improvement after closed reduction and pinning, then open exploration of the antecubital fossa should be performed.
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197
most common causative organism in septic bursitis?
Staph aureus (80% or more of culture proven cases)
198
what is the best way to address a Vancouver B2 periprosthetic femoral fx?
-Revision implant using a long-stem cementless prosthesis
199
what is the maximum acceptable difference in rotational malreduction for femoral version in treating femoral shaft fx's w/ IMN?
15 degrees compared to contralateral leg
200
in pts w/ isolated closed fx of tibial shaft treated w/ IMN, which factor is associated w/ increased risk of adverse events such as nonunion, revision surgery, or fx of implants?
There was an increased risk of negative events in patients with a high-energy mechanism of injury (odds ratio [OR] = 1.57; 95% confidence interval [CI], 1.05 to 2.35), a stainless steel compared with a titanium nail (OR = 1.52; 95% CI, 1.10 to 2.13), a fracture gap (OR = 2.40; 95% CI, 1.47 to 3.94), and full weight-bearing status after surgery (OR = 1.63; 95% CI, 1.00 to 2.64). There was no increased risk with the use of nonsteroidal anti-inflammatory agents, late or early time to surgery, or smoking status. Open fractures had a higher risk of events among patients treated with reamed nailing (OR = 3.26; 95% CI, 2.01 to 5.28) but not in patients treated with unreamed nailing (OR = 1.50; 95% CI, 0.92 to 2.47). Patients with open fractures who had wound management either without any additional procedures or with delayed primary closure had a decreased risk of events compared with patients who required subsequent, more complex reconstruction (OR = 0.18 [95% CI, 0.09 to 0.35] and 0.29 [95% CI, 0.14 to 0.62], respectively).
-SPRINT STUDY DATA
201
Multiple studies have shown a high incidence of associated ligamentous and meniscal injuries among patients with proximal tibia fractures. Gardner et al described injury to 1 or more cruciate/collateral ligaments in 77% of their series. Lateral meniscus injuries were most common with an incidence of 91%. Wang and associates showed higher rates of soft-tissue injury in Schatzker types II and IV patterns, with incidences of 74% and 85%, respectively.
.
202
Studies demonstrate that surgical treatment of distal radius fractures in elderly people does not result in improved outcomes. Although nonsurgical treatment resulted in worse radiographic findings for this patient, these findings did not translate into worse functional outcomes.
.
| -pts in operative group have improved grip strength only
203
Components of the syndesmosis of ankle?
- anterior-inferior tibiofibular ligaments (AITFL)
- posterior-inferior tibiofibular ligament (PITFL)
- IO membrane
- interosseous ligament (IOL)
- inferior transverse ligament (ITL)
204
typically the most important initial step in evaluating scapulothoracic dissociation?
-rule out an associated vascular injury w/ pulse exam and brachial-brachial index
205
need structure for bone graft to be osteoCONDUCTIVE
.
206
bone graft from reamer irrigator aspirator is what?
-osteogenic, osteoconductive, and osteoinductive
207
The use of perfusion pressure instead of absolute pressure has been shown to be more physiologically relevant. As the literature supports, fasciotomies can be avoided if the perfusion pressure (diastolic blood pressure minus compartment pressure) is greater than 30 mmHg.
.
208
what is the proper location of a trochanteric nail starting point?
- dependent on the relative position of the trochanter to the axis of the femoral shaft
- must also consider the geometry of the proximal bend of the selected nail
209
In the management of displaced periprosthetic distal femoral fractures, when comparing locked plating, retrograde intramedullary nail (RIMN), nonlocking plating techniques, and nonsurgical treatment, locked plating has been shown to?
Ristevski and associates reported that locked plating and RIMN offer significant advantages over nonsurgical treatment and conventional (nonlocked) plating techniques. Locked plating demonstrated a trend toward increased nonunion rates when compared with RIMN. Malunion was significantly higher with RIMN than locked plating. No statistically significant increase in the need for secondary surgical procedures was associated with locked plating.
210
What is a significant risk factor for recurrence of clubfoot deformity after correction with the Ponseti method?
Noncompliance with brace wear
-Brace wear noncompliance was a significant risk factor for recurrence of clubfoot deformity in a study by Dobbs and associates. The only other significant risk factor identified in that study was the level of parental education. Parents with a high school education or less had a 10 times higher risk for recurrence compared to those parents with an educational level higher than high school. The other factors listed of initial severity of deformity, age at initiation of treatment, and family income were not found to be significantly associated with clubfoot recurrence.
211
what is the most common type of malignant tumor deriving from chronic osteomyelitis?
Squamous cell carcinoma
212
Initial cartilaginous injury at the site of tibial pilon fractures can best be described as cell death
Tochigi and associates showed in a human model of tibial pilon fractures that cell death peaks immediately postimpact in the superficial zones of the cartilage surrounding fracture margins.
213
most common deformity of proximal tibia fx's?
VALGUS and PROCURVATUM
214
Remember that you DO NOT need a proximal tibia LOCKING plate for isolated lateral tibial plateau fx's, a NONLOCKING plate is much less expensive and equivalent in terms of outcomes
.
215
volar or dorsal plating for distal radius fractures?
Yu et al reviewed 104 distal radius fractures treated with either dorsal or volar plating. There was no difference in the rate of tendon irritation or rupture between the groups. Volar plating was associated with significantly more neuropathic pain complications.
216
cutoff for bone mineral density and potential for successful internal fixation in proximal humerus fractures?
- combined cortical thickness >4mm
- Nho et al. reviewed the management of displaced proximal humerus fractures. They advocate using combined cortical thickness as a predictor of bone mineral density and potential for successful internal fixation. Cortical thickness is measured on the AP radiograph (adjusting for magnification). The average of medial and lateral cortical thickness at 2 levels is used.
217
"parts" in proximal humerus fractures?
- greater tuberosity, lesser tuberosity, head segment, shaft segment
- separate part is considered if displacement >1cm or angulation >45deg
218
Predictors of humeral head ischemia in proximal humerus fractures?
Hertel et al. reviewed predictors of humeral head ischemia. Good predictors of disrupted humeral head viability include minimal metaphyseal extension (<8mm) and medial hinge disruption (displacement >2mm) and the fracture type. Moderate and poor predictors include 4-fragment fractures, angular displacement of the head >45°, tuberosity displacement >1cm, glenohumeral dislocation, head-split, and 3-fragment fractures.
219
Three-part proximal humerus fractures with adequate cortical thickness (>4mm) are best treated with ORIF with a locking compression plate +/- bone graft. Non-operative management is a better option for unifocal extraarticular Type A surgical neck fractures with <66% displacement, or bifocal fractures with poor bone stock (cortical thickness <4mm).
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220
The mangled extremity severity score (MESS) utilizes all of the following variables EXCEPT...?
Time from admission to surgery
-MESS is a tool utilized to help predict limb salvage success versus primary amputation at the time of presentation. As a screening tool for amputation, this scoring system has a high specificity but low sensitivity, as scores lower than 7 may also ultimately need amputation
-The scoring system is as follows: 1. Skeletal / soft-tissue injury 2. Limb ischemia 3. Shock 4. Age
Limb category scores are doubled for ischemia > 6 hours. The system's original designers reported a cutoff of 7 as predicting amputation.
-Note that multiple studies have found that the MESS score did NOT predict functional outcomes at 6 or 24 months
221
Innervation of subscapularis?
-Innervated by the upper and lower subscapular nerves (may also be innervated by a middle subscapular nerve), derived from the POSTERIOR CORD (C5-6) of the brachial plexus
222
innervation of the biceps brachii
musculocutaneous nerve derived from the LATERAL CORD
223
Innervation of pec major
Medial and lateral pectoral nerves derived from the MEDIAL AND LATERAL CORDS, respectively
224
innervation of rhomboid major
innervated by the dorsal scapular nerve, derived from the C5 NERVE ROOT
225
Innervation of the supraspinatus
innervated by the suprascapular nerve derived from the UPPER TRUNK
226
In treating tibial plateau fractures, what has been shown to have the least amount of articular subsidence on follow-up examinations?
Calcium phosphate
227
when does CRP peak after ORIF?
C-reactive protein (CRP) should peak by 48 hours after surgical fixation of bony orthopedic injuries, and decrease thereafter. This is important to recognize, as an increasing CRP after 48 hours is predictive for postoperative infection, and is more predictive in the first postoperative week than local erythema, persistent serous drainage, and increasing serial ESR.
228
the most common complication after open reduction internal fixation of distal humerus fractures?
Stiffness and decreased elbow ROM
- loss of motion can arise from "a variety of causes, including articular incongruity or adhesions, capsular contractures, loose bodies, heterotopic ossification, and prominent hardware."
229
Of all the pelvic ring injury types, anteroposterior compression type III pelvic ring injuries have the highest rate of what?
Need for transfusion
-APC type III have the highest rate of mortality, blood loss, and need for transfusion. They also have a high rate of urogenital injury and abdominal organ injury. Lateral compression injuries (especially type III) have the highest rate of head injury. Vertical shear and combined injuries also have significant rates of concomitant injuries.
230
Treatment of chronic osteo and infected nonunion of tibial shaft fracture?
Successful treatment requires debridement, removal of the existing tibial nail, placement of an antibiotic-impregnated rod and IV antibiotics. Sinus tract excision and biopsy is important to exclude malignant transformation (Marjolin's ulcer).
231
Pipkin type II femoral head fracture?
fracture which is superior to the fovea
-Differentiation between Pipkin I and Pipkin II fractures can be important, as suprafoveal injuries often require surgical fixation.
232
Saline load test for detections of traumatic knee arthrotomies
- Nord et al. found that the volumes of saline that were needed in order to effectively diagnose 75%, 90%, 95%, and 99% of the knee arthrotomies were 110, 145, 155, and 175 mL, respectively. They also found that an inferomedial injection location required significantly less fluid than a superomedial injection location did.
- Addition of methylene blue to the saline load test does not increase the sensitivity of the test. (Metzger et al.)
- Physical exam performs worse than the conventional saline load test to detect traumatic knee arthrotomies
- Konda et al. performed a study evaluationg the role of CT scan versus saline load test. They found that the sensitivity and specificity of the CT scan to detect traumatic arthrotomy was 100%. In a subgroup of 37 patients that received both a CT scan and the conventional saline load test, the sensitivity and specificity of the CT scan was 100% compared to 92% for the saline load test (p<0.001).
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Proximal humerus fractures
Proximal humerus fractures account for approximately 5% of all fractures, with incidence increasing to reflect an aging population and related osteoporosis. Treatment is dependent upon the mechanism of injury, the patient’s physiologic age and activity level, the fracture pattern, and rotator cuff integrity. Most of these injuries are nondisplaced or minimally displaced and are associated with a good overall prognosis with nonsurgical treatment and temporary impairment. A patient with a nondisplaced surgical neck fracture should be treated without surgery. K-wire stabilization, although technically difficult to achieve, is an option for compliant patients with 2-part, 3-part, and valgus-impacted 4-part fractures who have adequate bone stock. Valgus-impacted 4-part fractures pose reduced risk for osteonecrosis because of the preserved blood supply through the medial hinge, which allows for this technique. For displaced 2-part fractures accompanied by metaphyseal comminution, K-wire fixation cannot provide adequate stability to initiate a graduated home exercise or outpatient physical therapy program. Formal open reduction with intramedullary or plate fixation in addition to bone grafting (fibular strut allograft) is the best surgical option for the clinical scenario involving a displaced surgical neck fracture with comminution. Osteosynthesis of 3-part fractures may be feasible for physiologically young and active patients without humeral head involvement and osteoporosis. Current indications for primary hemiarthroplasty include most 4-part fractures, 3-part fractures and dislocations in elderly patients with osteoporotic bone, head-splitting articular segment fractures, and chronic anterior or posterior humeral head dislocations with more than 40% of articular surface involvement. Because of the intra-articular nature of this patient’s 4-part injury in this scenario, hemiarthroplasty with anatomic reconstruction of the greater and lesser tuberosities is most appropriate. Relative indications for hemiarthroplasty also include fractures with more than 20 degrees of varus, associated moderate to severe osteopenia, and revision surgery for failed osteosynthesis. Currently accepted indications for rTSA include scenarios in which the fracture pattern, level of comminution, bone quality, and rotator cuff deficiency preclude plate fixation or hemiarthroplasty. Scenarios involving 4-part fractures and associated rotator cuff tears and tuberosity comminution are best served with a reverse shoulder prosthesis. One of the positive attributes of this implant is the ability to achieve functional forward flexion and abduction regardless of tuberosity healing, position, and degree of comminution. Caution is warranted with this surgical technique because complication rates are higher than for hemiarthroplasty reconstruction. Acute, irreducible 2-part fracture-dislocations of the proximal humerus necessitate open reduction and internal fixation of the affected tuberosities (posterior, lesser tuberosity; anterior, greater tuberosity) through screw, anchor, and/or suture fixation. These fracture-dislocations can be managed with this technique because of the integrity of the vascular supply, which is maintained by the soft-tissue attachments to the intact tuberosities. Repeated attempts at a closed reduction in the 37-year-old with the posterior fracture-dislocation could result in neurovascular injury and myositis ossificans and should be avoided. Arthroplasty reconstruction in this scenario should not be the index procedure in light of concerns regarding implant survivorship in patients of this age and their assumed elevated activity levels.
