OITE Flashcards
The highest risk of viral transmission with blood transfusion is…
Hepatitis B.
Donor blood is screened for…
HIV-1 HIV-2 HBV HCV West Nile virus Syphilis
Normal lactate
Less than 2.5
Normal gastric mucosal PH
Greater than 7.3
Normal base deficit
-2 to +2
Injury severity score equal to
A squared plus B squared plus B squared
A, B and C refer to top three most severely injured regions
Risk factors for under triage in trauma bay
Female, age greater than 65, 2+ comorbid conditions, non-white, GCS 15
Risk factors for mortality after poly trauma in elderly individuals
ISS, Initial GCS less than or equal to 10, admission PH, admission lactate, need for ventilation
After major trauma, compared to men, women have…
Poorer quality of life outcomes ( higherPTSD, more sickleave time)
Compared to adults, with regards to physiologic inflammatory response, children have…
A dampened systemic response but a robust local inflammatory response. In children, multi organ failure occurs early after the admission, during resuscitation.
In adults, multi organ failure begins 48 hours after the injury due to the robust systemic response.
Neurogenic shock
Disruption of sympathetic activity leading to hypotension and bradycardia
Spinal shock
Temporary loss of spinal cord function below the level of the injury; in addition to loss of sympathetic tone (neurogenic shock), There is complete loss of sensory motor function and reflexes
Class 2 hemorrhagic shock Is differentiated from class three by…
Blood pressure.
Class 2:15 to 30% blood volume loss. Tachycardic and normotensive
Class 3:30 to 40% blood volume loss. Tachycardic and hypotensive
Antibiotics for type one and two open fracture
First generation cephalosporin, gram-positive coverage. Example is ancef.
Antibiotics for type three open fracture
First generation cephalosporin and aminoglycoside. Example gentamicin for Graham negative coverage
Antibiotics for farm injury or bowel contamination of a fracture
Add penicillin for anaerobic coverage. Example clostridium.
Best method of irrigation for open fracture
Saline at low flow or pressure
In the masquelet technique, the membrane around the spacer harbors…
BMP-2 which peaks at four weeks and returned to baseline at six months
PMMA antibiotic spacer has the highest antibiotic concentration At…
24 hours. Levels remain bactericidal for up to four months.
Vancomycin is released in a…
Time dependent manner.
Tobramycin is released in a…
Concentration dependent matter
Maximum recommended concentration of vancomycin
10.5 g/ 40 mg of PMMA
Maximum recommended concentration of Tobramycin
12.5 g per 40 mg of PMMA
Treatment of intra-articular gunshot wound
I&D And retrieval of bullet fragments to prevent plumbism
Gunshot wound to the hip is most Commonly associated with…
Bowel perforation. Needs laparotomy.
Gun shot wound to the spine treatment
Antibiotics for 24 to 48 hours or longer if there is intestinal injury. Needs decompression and fusion only if there is neurologic deficit or instability.
During initial exploration of a gun shot wound, if there is nerve transaction…
It should be treated 1 to 3 weeks post injury.
What nerve has the worst functional recovery after repair due to a gunshot wound?
Ulnar nerve
When comparing amputation to limb reconstruction, there is no difference between…
Return to work, functional outcomes, cost
After severe lower extremity injury, psycho social function…
Does not improve with time.
After severe injury to soft tissue, hyperbaric oxygen therapy can be utilized. Contraindications include…
Insulin pump, pacemaker and ICD.
The most energy efficient amputation is…
Syme amputation
Energy expenditure for traumatic versus vascular BKA
25% versus 40%
Does a bilateral BKA or unilateral AKA result in higher energy expenditure?
Unilateral AKA. This is 65% versus 40% for bilateral BKA
Factors for improved wound healing
Albumin greater than three ABI greater than .45 Lymphocyte count greater than 1500 Toe pressure greater than 40 Transcutaneous oxygen tension greater than 30
Compared to a regular BKA, and Ertl bridging synostosis…
Provides equivalent functional outcomes but higher complications
What should you do with the dog ears on a BKA?
Leave them alone to prevent injury to the blood supply to the flap
In children, What is the most proximal level at which walking speed can be maintained without significantly increase in energy expenditure?
Knee disarticulation
What artery hasto be patent for any amputation distal to a BKA?
Posterior tibial artery. Requires a viable heel pad.
ChoPart amputation
Through the transverse tarsal joints. Can lead to Equinus deformity so need to perform Achilles tendon lengthening and transfer the tibialis anterior to the talar neck
Lisfranc amputation
Through the TMT joints. Need to maintain insertion of peroneus brevis or will lead to equinovarus deformity
Treatment of post amputation neuroma pain
TMR
High rates of SLAP repair failures have been associated with…
age > 36. Consider tenotomy for this age group.
Treatment for clavicle
sling (NOT figure of 8)
Predictors of clavicle nonunion
female, displacement, comminution, advanced age
Nonoperative treatment of clavicle fractures has higher risk of…
symptomatic nonunion and malunion, lower functional outcomes
What provides the AP stability fo the AC joint?
superior and posterior AC ligaments
What provides the superoinferior stability of the AC joint?
CC ligaments (conoid is medial to trapezoid)
Congenital pseudarthrosis of the clavicle is usually located at…
the middle third of the right clavicle.
Treatment of sternoclavicular dislocation is generally…
non-op except for posterior SC dislocation with compression of the trachea and esophagus (closed vs open reduction with thoracic surgery avaialble)
What is predictive of intact vascular supply for proximal humerus fx?
posteromedial calcar spike > 8 mm
Predominant blood supply to the humeral head?
posterior humeral circumflex artery
Most common complication of ORIF of porximal humerus fractures
screw cut out and intraarticular penetration
What is key to preventing varus collapse of proximal humerus fx?
adding an inferomedial screw to purchase the calcar
What guides the humeral prosthesis height for rTSA?
superior edge of of the pec major insertion.
The PMI is 5.6 cm distal to the superior aspect of the humeral head.
Normal retroversion and neck shaft angle of the humerus?
30 degrees of retroversion
130-140 degrees neck shaft angle
rTSA dislocation is associated with…
subscapularis rupture/insufficiency postoperative. Dislocation usually occurs with arm in extension, ADD and ER - anterior dislocation)
Treatment of isolated greater tuberosity fracture
Surgery for > 5 mm displacement. The cuff pulls the GT superior (which blocks abduction) and posterior (which blocks ER).
When and what is considered humeral shaft nonunion?
Fracture site mobility at 6 weeks.
Indications for plating of humeral shaft fracture
open fracture, vascular injury requiring repair, brachial plexus injury (higher nonunion rate with nonop), floating elbow, b/l humeral shaft fx, polytrauma
When to use anterior vs posterior approach to the humerus
Anterior: proximal and middle third humeral shaft
Posterior: middle and distal third
In relation to the heads of the triceps, where does the radial nerve lie?
Medial to long and lateral heads and proximal to the deep head. You can follow the posterior antebrachial cutaneous nerve proximally to find the radial nerve
When cabling the humerus, what reduces risk of iatrogenic radial nerve injury?
fixation proximal to the inferior edge of the lat dorsi
When compared to plating humerus, IMN is associated with…
higher total complications (shoulder stiffness and impingement).
IMN humeral nail distal interlock dangers
A to P: musculocutaneous nerve
L to M: radial nerve
Radial nerve palsy in closed vs open humeral shaft fracture
Closed: likely neuropraxia –> observe
Open: likely neurotmesis –> explore and repair
First and last muscles to recover with radial nerve palsy
Brachioradialis is first (wrist extension in radial deviation) and EIP is last to recover (index finger MCP hyperextension)
When operating on a distal humerus and deciding between TEA or ORIF, what should be avoided?
Avoid olecranon osteotomy during exposure as this may affect TEA.
Chevron osteotomy for olecranon osteotomy
Perform 2 cm distal to triceps insertion in bare area of ulna. AIN is at risk.
Postoperative ulnar neuropathy is associated with…
intra-op ulnar nerve transposition.
What does a double arc sign represent?
coronal shear fracture of the capitellum with extension into the trochlea. This requires exposure of the entire lateral column, elevating off the common extensors and capsule.
When operating on the lateral aspect of the elbow, disruption of the posterior perforating vessels leads to…
AVN of the capitellum.
When operating on the lateral aspect of the elbow, disruption of the LUCL leads to…
valgus posterolateral rotatory instability.
Mechanism of elbow dislocation
fall onto outstretched arm (axial compression, forearm supination, and valgus load
After closed reduction of an elbow dislocation, it should be splinted in…
elbow flexion and pronation.
Direction of elbow dislocation is usually…
posterolateral and structures fail from lateral to medial. LCL fails via ligament avulsion off the lateral epicondyle.
Most common complication of elbow dislocation is…
loss of terminal extension
Most common associated injury with pediatric elbow dislocation is…
medial epicondyle fracture. Treat surgically if > 5 mm displacement or incarcerated fragment.
Ulnar nerve is at risk of entraptment.
For a simple pediatric elbow dislocation, treat with…
splint for 10 days followed by protected ROM.
Mechanism of a terrible triad
fall onto outstretched hand with the forearm in supination and valgus thrust
Order of fixation of terrible triad
radial head, then coronoid, then LCL and finally MCL
When to fix vs repair radial head
fix radial head if < 3 fragments and replace if greater than or equal to 3 fragments. Never perform acute resection.
When to repair coronoid fracture
if less than 50%, may not have to repair (?). Less than 10% does NOT need repair.
If only LCL is ruptured in terrible triad, then splint in…
flexion and pronation.
If LCL and MCL are ruptured in terrible triad, then splint in…
neutral and flexed position.
Terrible triad post op ROM should start at…
48 hours.
The anterior bundle of the MUCL inserts on…
the sublime tubercle (the anteromedial facet of the coronoid).
Fracture of the sublime tubercle or injury to the anterior bundle of the MUCL leads to…
varus instability/varus posteromedial rotatory instability.
When treating olecranon fractures, penetration of the anterior cortex of the ulna leads to…
AIN injury and mechanical block to prono-supination.
Treatment of comminuted olecranon fracture in elderly, osteoporotic patient
excision with triceps advancement if fracture involves < 30-50% of the articular surface.
HO prophylaxis
- Indomethacin
- single radiation (700 cGY dose) either 4 hours before or within 72 hours after surgery
With regards to a monteggia fracture, the apex of the ulnar fracture is…
generally in the same direction as the radial head dislocation.
What nerve is at greatest risk after a Monteggia fracture?
PIN which leads to radial deviation of the hand with wrist extension (from pull of the mobile wad)
What may block anatomic reduction of the monteggia fracture?
annular ligament interposition in the radiocapitellar joint
Treatment of radial head fracture with no or minimal displacement
early ROM
Treatment of radial head fracture with > 2 mm displacement
< 3 fragments: ORIF
comminuted: radial head replacement
Safe zone for HW placement of radial head
90 degree arc from radial styloid to Lister’s tubercle
Acute radial head resection can lead to…
proximal radial migration resulting in distal ulnar impaction syndrome
Esesx-Lopresti injury
radial head fracture with DRUJ dislocation and disruption of the interosseous membrane
How position forearm with lateral approaches to the elbow…
pronate the forearm to pull the PIN anteriorly away from the field
What is the most important ligament of the interosseous membrane in the forearm?
central band
Best plate to use for BBFF
- 5 mm LC-DCP
4. 5 plate has higher risk of refracture
for BBFF, do not remove hardware before…
15 months. after plate removal, consider bracing to prevent refracture.
Single incision for BBFF has higher risk of…
synostosis.
On x-ray, mature HO is characterized by….
sharp cortical margins.
When to use bone graft on BBFF
if there is segmental bone loss of the radius.
Formal PT after DRF (surgery or injury) does…
not change outcomes
CRPS prevention
vitamin C 500 qd for 50 days
CRPS type 1 vs 2
type 1: no identifiable nerve lesion
type 2: identifiable nerve lesion
Treatment of EPL rupture
EIP to EPL transfer.
EPL rupture of volar plate fixation is related to…
screw penetration through the dorsal cortex.
FPL rupture of volar plate fixation is related to…
plate placement distal to the watershed line and protrusion of the plate beyond volar lip of the radius.
Dorsal plate fixation of the DR is reserved for…
intra-articular DRF with significant comminution.
Reduction of a galeazzi fracture may be blocked by….
ecu interposition.
At what level do radial shaft fractures have a higher incidence of DRUJ instability?
< 7.5 cm from articular surface.
The DRUJ is most stable in…
supination.
After fixing a DRF, if the DRUJ is stable, then immobilize in…
supination if the DRUJ dislocates dorsally or pronation if DRUJ dislocates volarly.
The TFCC has 7 components:
- volar and dorsal radioulnar ligaments (primary stabilizers of the DRUJ)
- central articular disc
- meniscal homologue
- ulnolunate and ulnotriquetral ligaments
- ulnar collateral ligament
- ECU tendon sheath
A positive ulnar fovea sign indicates…
TFCC tear
Position of hip in dislocation
Posterior: hip will be flexed, ADD and IR
Anterior: hip will be flexed, ABD and ER
If open reduction of a hip is required, you should approach from…
the direction of dislocation since those soft tissues are already compromised.
Most common complication of a FNF…
osteonecrosis. Main blood supply is the MFCA.
Biggest risk factor for necrosis in FNF
pre-operative degree of displacement
CRPP treatment of FNF
inverted triangle with inferior screw in posteroinferior neck adjacent to calcar
Treating a FNF with DHS leads to…
higher AVN than cannulated screws but equivalent union
Treatment of femoral neck nonunion in young patient
valgus intertrochanteric osteotomy which converts vertical fracture line (shear force) to a horizontal fracture line (compressive force)
Treatment of femoral neck stress fracture
compression side: PWB (but consider CRPP if > 50% neck is involved)
tension side: CRPP
In peri-troch hip fracture, the proximal fragment is displaced…
flexed (iliopsoas), abducted (gluts) and ER (SERs)
2 hole vs 4 hole DHS
equivalent
There has been increased use of CMN over DHS for intertroch fractures due to…
higher medicare reimbursement.
Treatment of stable intertroch fx
DHS or short locked CMN
Performing CMN nail in lateral position advantages
- easier to identify starting point
- facilitates fracture reduction
Most common deformity with CMN of peritroch fractures
varus and flexion (procurvatum)
No differences been shown between short and long CMN except…
cost (higher with longer nails)
what percentages of patients with femoral shaft fracture have ipsilateral FNF?
as high as 10%
Femoral shaft fracture blood loss
1250 cc
Sx of fat embolism syndrome
petechiae, hypoxemia and AMS
Weakest muscle groups after antegrade IMN femoral fx
quads and abductors
If you use a straight nail with a trochanteric starting point, this can lead to…
varus malalignment.
Most common complication after IMN femur is…
malrotation. CT is best to diagnose. Defined as > 15 degrees compared to contralateral side.
Using a fracture table to fix femoral shaft fracture increases risk of…
internal malrotation.
If the LE IR is increased after femur IMN, then either…
too much femoral anteversion of proximal fragment or too much IR of distal fragment.
After IMN of femur, if the LE ER is increased, then either…
too much femoral retroversion proximally or too much ER distally.
Treatment of femoral shaft nonunion
compression plating with bone graft
Shortening of the femur will deviate the mechanical axis…
medially whereas lengthening will deviate it laterally.
Hoffa fracture
coronal fracture of femoral condyle (lateral more common than medial)
For distal femur fractures, a golf club deformity will occur if the locking plate is placed…
too far posterior distally.
Blood supply to the patella
genicular arteries arising from the popliteal
How to minimize wire migration with patella fx
bend k-wires both proximally and distally
Predictors of fixation failure for patella fractures
increasing age, fixation with k-wires (compared to screws)
Bipartite patella is most commonly located…
superolateral. Has smooth cortical borders and fibrocartilage between the two fragments.
How to treat pediatric patellar sleeve fracture
ORIF, usually with suture fixation
What structures are at risk with knee dislocation
Common peroneal nerve and popliteal artery
SPN deficit
peroneal brevis and longus
senation over dorsum of foot
DPN deficit
TA, EHL, EDL
sensation over 1st dorsal webspace
If patient is pulseless after reduction of knee…
vascular consult with exploration (NOT imaging).
Buttonholing at the knee is caused by…
posterolateral dislocation with the medial femoral condyle coming through the capsule (dimple sign). This can prevent closed reduction.
Treatment of multilig knee injury with early arthroscopy leads to…
increased risk of compartment syndrome due to capsular defects.
What is a poor prognostic factor after multi-lig knee injury?
morbid obesity
Traumatic knee arthrotomy joint loading
175 cc - detects 99%
155 cc - detects 95%
Lateral tibial plateau is…
convex and proximal; medial plateau is concave and distal
Lateral plateau fracture and meniscus tear is associated with…
> 10 mm articular depression.
With plateau fractures and meniscus tears, treat radial tears with…
debridement and longitudinal tears with repair.
Primary goal of tx of plateau fx
restore joint stability and limb alignment (articular reduction is 2ndary goal)
Does timing to definitive ORIF for plateau fractures after fasciotomy influence infection risk?
no
calcium phosphate
less subsidence than even autograft
calcium sulfate
not preferred because of fast resorption and serous wound drainage
Risk factors for infection after tibial plateau ORIF
- male
- smoker
- high ASA
- pulmonary disease
- bicondylar pattern
Treatment of plateau fractures with hybrid external fixation leads to…
higher malunion rates comapred to ORIF.
TKA after tibial plateau fx is associated with…
higher complications, equivalent patient reported outcomes and satisfaction.
Starting point for tibial IMN
just medial to the lateral tibial spine and at the reflection point between the tibial plateau and anterior tibial metaphysis
Proximal third tibial shaft fracture deformity
valgus and procurvatum
where to place poller screws for proximal third tibia fractures
-posterior (to prevent procurvatum) and lateral (to prevent valgus)
Suprapatellar or semiextended position nailing for proximal third tibial shaft fractures leads to…
procurvatum
lateral entry point for proximal third tibial shaft fractures leads to…
valgus
Best way to prevent malalignment of distal third tibial shaft fractures
plating. Plating of the fibula can also help.
Deformity seen with isolated tibial shaft fracture with intact fibula
varus
Why can you see a dropped hallux after tibial IMN?
transient peroneal nerve neurapraxia –> EHL weakness/sensory deficit in 1st websapce
danger with proximal tibia LISS plating
SPN injury when placing perc screws at holes 11-13
Soft tissue coverage of the leg
proximal third: use gastroc flap
middle third: use soleus flap
distal third: use free flap
Gastroc flap is supplied by…
sural artery
compartment syndrome is a compromise of…
venous outflow relative to arterial inflow.
Diagnosis of exertional compartment syndrome
resting P > 15
1-min post exercise P > 30
5 minute post exercises P > 20
Most accurate measure of exertional compartment syndrome
continuous pressure measurement
Recurrence of exertional compartment syndrome is most often due to…
postsurgical fibrosis within the fascial defect.
3 main fragments of a pilon fracture
- anterolateral/Chaput (AITFL)
- posterolateral/Volkmann (PITFL)
- medial malleolus (deltoid)
after pilon fracture (or any intra-articular fracture), chondrocyte apoptosis occurs…
in the superficial zone of cartilage at fracture margins.
Treating a pilon with acute fibular fixation and ex fix is associated with…
increased post-op complications.
Brake time after long bone diaphyseal/metaphyseal ORIF:
returns to normal 9 weeks after surgery or 6 weeks after initiation of weight bearing
How to evaluate the integrity of the deltoid ligament
manual or gravity ER stress test (check medial clear space)
Disadvantages of lateral vs posterior fibular plating
lateral: HW prominence, intra-articular screw penetration
posterior: peroneal tendonitis (but biomechanically stronger)
Treatment of supination adduction ankle fracture
buttress plating of medial mal and place screws parallel to plafond
Interval for posterior approach to ankle
between FHL and peroneus longus
Syndesmosis is most unstable in…
AP plane
4 ligaments of the syndesmosis
- AITFL
- PITFL
- transverse tibiofibular ligament
- interosseous ligament
Most sensitive/specific test for syndesmotic injury
MRI (see lambda sign on coronal)
Bosworth fracture dislocation
fibula is entrapped behind the posterolateral ridge of the tibia at the incisura fibularis
Treatment of diabetic ankle fractures
ORIF with multiple syndesmotic screws, immobilize 12 weeks instead of 6
(non-op treatment poses risk for loss of reduction)
greatest risk factor for postop complications of diabetic ankle fracture is
peripheral neuropathy
The superior glenohumeral ligament resists…
Inferior translation at 0° of abduction
The middle glenohumeral ligament resist…
Anterior and posterior translation at 45° of abduction
The inferior glenohumeral ligament resists…
Anterior and if your translation at 90° of abduction and external rotation (Anterior band)
Posterior translation at 90° of flexion and internal rotation (posterior band)
Buford complex
A congenital variant with no anterior superior labrum and a cord like MGHL
Bankart lesion
Avulsion of anterior band of a IGHL and anterior labrum
Boundaries of the rotator interval
Supraspinatus tendon superior, subscapularis tendon inferior, transverse humeral ligament lateral
Content of the rotator interval
SGHL, coracohumeral ligament, long head of biceps tendon
What is the strongest predictor of redislocation of the shoulder?
Age less than 40 at time of dislocation
For an anterior shoulder dislocation, the shoulder is unstable in…
Abduction and external rotation
Glenoid bone loss is best assessed with…
3D CT reconstruction
Latarjet procedure
Performed for glenoid deficiency more than 20 to 25%. This is a coracoid transfer to the glenoid. Musculocutaneous nerve is most commonly injured. Axillary nerve also at risk.
Remplissage procedure
Transfer of posterior capsule and infraspinatus into hill sachs lesion of the posterosupererior humeral head
A large hill sachs lesion will engage with the glenoid when…
There is more than 25 to 40% of the bone missing. There will be catching sensation when the arm is 90° abducted and externally rotated.
After a remplissage procedure, avoid…
Adduction with shoulder forward flexed because this will stress the posterior myocapsulodesis
Blood supply to the talus is via…
PT artery branches - artery of the tarsal canal (main branch) and deltoid branch
Option to preserve the deltoid ligament for surgical approach to the talus
medial malleolar osteotomy
Where is the comminution typically located in a talus fracture?
dorsal (leads to dorsal malunion) and medial (leads to varus malunion)
Treatment of a displaced talar neck fracture
ORIF thru medial and lateral incisions
What do you do with an extruded talus fragment?
clean and reimplant during ORIF
Hawkins sign
subchondral lucency on xrays (indicating bone resorption) at 6 weeks is a good prognostic sign indicating intact vascularity
After a talus fracture, is posttraumatic tibiotalar or subtalar arthritis more common?
subtalar
What is the common skier/snowboarder fracture?>
fracture of lateral process of talus (lateral talocalcaneal ligament)
If chronic, comminuted and symptomatic: fragment excision
Superomedial (constant) fragment of calcaneus
FHL wraps inferior to the sustentaculum tali.
Thus, FHL is at risk when placing lateral to medial screw, esp when the screw is too long (leads to tethered FHL and a fixed, flexed hallus).
Treatment of subtalar arthritis with loss of calcaneal height after calc fx
distraction bone block subtalar arthrodesis
***will see limited dorsifelxion and anterior ankle impingement
Factors associated with better outcomes after calcaneus ORIF
- female
- non workers comp
- < 29 years old
- less comminution
- sedentary jobs
- Bohler’s angle 0-14
Bohler’s angle
The angle between two lines drawn tangent to the superior aspect of the anterior and posterior calcaneus (normal is 20-40 degrees)
Most common direction of subtalar dislocation
Medial is more common but lateral is more often open.
Block to reduction of medial subtalar dislocation
lateral structures (peroneal tendons, EBD)
Block to reduction of lateral subtalar dislocation
medial structures (PT, FHL/FDL)
Subtalar dislocation can also be associated with…
talonavicular dislocation.
Lisfranc ligament location
medial cuneiform to base of 2nd MT
Treatment of ligamentous or chronic lisfranc injury
open reduction and arthrodesis of TMTs 1-3
Treatment of bony lisfranc
ORIF of TMT 1-3 with screws (not K-wires)
APC pelvic ring injuries are associated with…
hemorrhage
LC pelvic ring injuries are associated with…
head injury
Difference between APC II vs III
II: posterior sacroiliac ligaments are intact
Complications associated with anterior subcutaneous pelvic fixator (INFIX)
HO is most common.
LFCN is most common nerve injury.
Femoral nerve injury leads to loss of knee extension.
What can result in underestimation of pelvic ring injury severity?
application of pelvic compression device and CT
Risk with SI screws
L5 nerve root (EHL) as it runs over the sacral ala
What do you see on inlet view for SI screws?
anterior-posterior screw placement
What do you see on outlet view for SI screws?
superior-inferior screw placement
what do you see on lateral sacral view?
entry point for SI screws
What pelvic ring injury poses the greatest risk for loss of fixation of SI screws?
vertical shear fracture
Risk factors for deep infxn after pelvic/acetabular sx?
obesity
leukocytosis
embolization
injury severity
The most common urethral injury associated with pelvic fracture is…
posterior urethral tear
**diagnose with retrograde urethrocystogram
How to treat a sacral insufficiency fracture if chronic and symptomatic
perc screws
Chronic pelvic ring instability is best assessed with…
alternating single-leg-stance pelvic xrays
How to treat parturition induced pubic diastasis
non-op (bedrest, binder) if less than 4 cm
What does a judet view show you?
iliac oblique: posterior column, anterior wall
obturator oblique: posterior wall, anterior column
What is a transverse acetabular fracture?
an elementary acetabular fracture pattern involving both columns
**axial CT demonstrates a vertical fracture line
Both column acetabular fracture
complete discontinuity between the articular surface and the posterior ilium
**see the spur sign on the obturator oblique view (which is the posterioinferior aspect of the intact ilium)
What protocol has lower joint reactive forces on the hip?
TTWB is lower than NWB.
What aspect of the acetabulum experiences the highest joint reactive forces?
posterosuperior
When treating acetabular fractures surgically, operate within…
5 days because it is easier to mobilize and reduce fracture fragments
What approach to the acetabulum has the highest risk of HO?
extended iliofemoral
What do you see on inlet iliac oblique view for perc screws?
AP screw placement in the pubic ramus
What do you see on the inlet obturator oblique view?
ensure screw placement within the inner and outer tables of the ilium
What do you see on the outlet obturator oblique view?
ensure placement outside of the joint (superior/inferior placement)
Corona mortis
anastomosis of the epigastric (branch of external iliac) and obturator (branch of internal iliac)
*needs to be ligated during Stoppa approach
The ulnar artery supplies which part of the palmar arch?
The ulnar artery supplies the superficial palmar arch while the radial artery supplies the deep palmar arch.
In the digit, the digital artery is located…
Dorsal to the digital nerve.
The rotator interval is an extension of…
the coracohumeral ligament.
What size Hill Sachs lesion requires bone grafting?
> 40%
Shoulder is at risk for posterior dislocation in…
flexion, adduction and IR.
What structure is most important in preventing posterior subluxation/dislocation of the shoulder?
subscapularis
To protect a posterior labral tear, avoid…
adduction with shoulder flexed for 3 weeks.
Treatment for a reverse hill-sachs lesion > 25-40%
McLaughlin - subscapularis transfer
or lesser tuberosity transfer (modified McLaughlin)
Luxatio erecta
inferior shoulder dislocation; will be fixed in abduction
Multi-directional instability is…
instability in 2 or more planes.
If MDI fails 6 months of PT, then treat with…
capsular shift and plication, closure of rotator interval.
Closure of the rotator interval will…
limit shoulder ER with the arm adducted.
Avoid thermal capsulorrhaphy because of…
chondrolysis.
Parsonage-Turner syndrome
aka brachial neuritis or neuralgic amyotrophy
intense shoulder/UE pain, multifocal weakness, fatty atrophy on MRI, EMG with denervation and reinnervation potentials
treatment: observation
Thoracic outlet syndrome
compression of brachial plexus –> paresthesias and sensorimotor deficits
compression of subclavian artery –> cool, pallor UE
compression of subclavian vein –> swelling/discoloration of UE
Symptoms of thoracic outlet syndrome occur with…
overhead activities.
Common causes of thoracic outlet syndrome
hypertrophy of scalene muscles, pancoast tumor, cervical rib
Quadrilateral space boundaries
teres minor, teres major, long head of triceps, humerus
Quadrilateral space contents
axillary nerve, PCHA
Quadrilateral space syndrome
compression in thrower during late cocking/early acceleration
Glenohumeral OA pattern
eccentric glenoid wear (posterior wear with posterior humeral head subluxation)
Glenohumeral inflammatory arthritis wear pattern
concentric glenoid wear leading to medialization of GH joint
Does TSA or hemiarthroplasty have lower revision rate?
TSA
After TSA, most common reason for revision is…
loosening (glenoid > humerus).
In rTSA, the center of rotation is moved….
medially and inferiorly which decreases deltoid abduction force and joint load.
Latissimus dorsi transfer can help with…
ER. If loss of ER, consider concomitant LD transfer with rTSA.
Risks with anterior vs posterior lat dorsi transfer
anterior: radial nerve
posterior: axillary nerve
For TSA, the thickness of the humeral head is about…
70% its radius of curvature.
The humeral head COR is…
4 mm posterior and 8 mm medial to the center of the humeral intramedullary canal.
Most common organism responsible for shoulder PJI
P. acnes (gram positive aerotolerant anaerobic bacillus)
Treatment of elbow flexion contracture > 30 or flexion < 130
static progressive elbow splinting
If elbow stiffness fails non-op tx, then…
perform capsular release with possible release of posterior oblique bundle of MCL (which is tight in flexion)
Arthroscopic contracture release of the elbow should be avoided in…
obese patients and those with prior elbow surgery.
Treatment of young laborer with advanced OA at the elbow with stiffness/pain
osteophyte resection and capsular release
Treatment of active patient with ulnohumeral arthritis and minimal radiocapitellar arthritis
arthroscopic ulnohumeral arthroplasty (fenestration of olecranon fossa, osteophyte debridement)
OCD of elbow is usually at…
the capitellum. Sx include painful catching, clicking, locking.
Total elbow arthroplasty is the best outcome for….
RA.
Best TEA systems are…
semi-constrained (linked).
The ulnar artery supplies which portion of the palmar arch?
The superficial palmar arch while the radial artery supplies the deep arch.
In the digit, the digital artery is located….
dorsal to the digital nerve.
What is the radial most extrinsic ligament of the wrist?
Radioscaphocapitate ligament
What can prevent reduction of a dorsal MCP dislocation?
volar plate
Location of wrist arthroscopy 3,4 portal
1 cm directly distal to Lister tubercle between EPL and EDC tendons
With the 6R or 6U wrist portal, what structure is at risk?
dorsal sensory branch of the radial nerve
With the 1,2 wrist portal, what structures are at risk?
superficial branch of radial nerve and radial artery
Function of free nerve ending
pain (nociception)
Function of meissner corpuscle
touch, pressure
function of pacinian corpuscle
deep pressure and vibration
function of merkel cell
sustained touch and pressure
function of ruffini ending
skin stretch
function of golgi tendon organ
muscle length and tension proprioception
1st dorsal compartment
EPB, APL
Pathology: deQuervain’s tenosynovitis
2nd dorsal compartment
ECRL, ECRB
Pathology: Intersection syndrome (often seen in rowers, pain 5 cm proximal to wrist joint)
3rd dorsal compartment
EPL
4th dorsal compartment
EIP, EDC, PIN
5th dorsal compartment
EDM
Pathology: Vaughan-Jackson syndrome (rheumatoid wrist, DRUJ instability causes volar carpal subluxation which leads to attritional rupture of digital extensor tendons from ulnar to radial; EDM is first to rupture)
6th dorsal compartment
ECU
Pathology: snapping ECU due to attenuation of ECU subsheath. ECU subluxates with forearm supination.
Mechanism of scaphoid fracture
fall onto outstretched wrist in extension
highest load transmission through the radioscaphoid articulation is when the wrist is extended
Most common location of scaphoid fractures in adults and children
adults: waist fracture
children: distal pole
What artery supplies the scaphoid?
the dorsal carpal branch of the radial artery (retrograde)
Treatment of scaphoid fracture
Nondisplaced or suspected: thumb spica cast
any displacement: ORIF
Approach to scaphoid ORIF
proximal pole fracture: dorsal approach
waist or distal pole or humpback deformity: volar approach
***use long screw down the central axis of the scaphoid
Best way to ensure proper screw seating below subchondral bone in scaphoid ORIF
direct visualization
Treatment of scaphoid nonunion in a young person
revision ORIF with vascularized medial femoral condyle graft
(obtain CT scan along axis of the scaphoid to assess union)