SAQ Flashcards
techniques to prevent malalignment in tibial nail
-
lateral blocking screw, posterior blocking screw
- in distal fragment
- blocking screws increase construct stiffness
- lateral start point to prevent valgus
- insertion technique critically important must be parallel to both lateral and anterior cortex
- semi-extended knee position prevents apex anterior or procurvatum deformity
- application of a provisional anterior unicortical plate
- useful to prevent procurvatum and anterior translation of the proximal fragment
*Endocrine problems associated with SCFE
Hypothyroid
GH deficiency
Panhypopituity
Renal osteodystrophy
Stabilizers of the DRUJ
- dorsal RU ligament
- volar RU ligament
- IOM
- radial syloid
- ulnar head
- ECU sheath
- pronator quadratus
4 risk factors of DVT associated with MRSA ostoemyelitis
From yellow article:
CRP > 6 at admission
Surgery
Age > 8
MRSA
from journal of infectious disease 2012
male
Release of a Varus knee
- osteophytes
- deep MCL
- SemiM, capsule
- superficial MCL
- PCL
- pes anserinus
- pop oblique ligamnet
What are the components of the lenke classification
Curve Type
Lumbar modifier
Sagittal thoracic modifier
3 predictors of successful treatment of UBC with methylprednisone
- Large size
- Multi-loculated
- Active lesion
Anatomical anomalies in other organ systems that are associated with congential scoliosis
- VACTERL
- Vertebral anomalies
- Anorectal Atresia
- Cardiac abnormalities
- TracheoEsophageal fistula
- Renal Abnormalities
- Limb Deformities
- Absent kidney, obstructive uropathy
- Atrial septal defect, patent ductus arteriosus, tetraology of fallot
- Clubfoot, DDH, Spregnels
Structures of the shoulder suspensory complex
glenoid
acromion
acromioclavicular ligaments
coracoclavicular ligaments
coracoid
Motion preserving procedures for SLAC
4 corner fusion
Proximal row carpectomy
+Changes associated with strength training
- results in increased cross-sectional area of muscle due to muscle hypertrophy
- results in increased motor unit recruitment +/- improved synchronization of muscule activity
- maximal force production is proportional to muscle physiologic cross-sectional area
What are features suggestive of a structural curve
- rotational component
- corrects to >25 deg on lateral bend
- >20 deg kyphosis (T10-L2)
- if no other curve fits this definition the curve with the largest cobb angle is considered structural
3 ways to prevent AVN in pediatric nail
Trochanteric start point
Lots of fluoro to prevent slipping to fossa
Sharp reamers to prevent reaming out into fossa
Important factors for placing trans-articular screws
- is the most stable form of fixation and obviates need for postoperative halo immobilization
- Contraindicaitons
- large/medial VA (CT angio)
- nonanatomic reduction C1/C2
- hypoplastic C2 pars
- substatial thoracic kyphosis
- Optimal screw length is 34mm
3 Way to fuse C1/2
-
C1 lateral mass screws / C2 pedicle screw construct - Harms
- C1 lateral mass screws
- C2 pedicle screws - still VA s at risk
-
C1-2 transarticular screw placement - Magerl
- is the most stable form of fixation and obviates need for postoperative halo immobilization
- Need to get a CT to check for high riding vertebral artery
-
C1-2 wiring techniques
- also used but are considered less stable and are usually treated with postoperative halo immobilization. Wiring techniques include
- Brooke’s technique
- Gallie’s technique
Considerations for DDH THA
-
Acetabulum
- smaller cup
- smaller cup means smaller head
- superior migration, false acetabulum
- loss of anterior/superior and lateral coverage
- Augment with screw fixation
- Augment with implant augments
- Offset-bore components are available that change the position of the head in the poly to reduce risk of instability
- smaller cup
-
Femur
- Previous surgeries
- Loss of canal
- Anteversion of neck
- May need to shorten
-
Soft tissue changes associated with superior migration
- Abductors become transverse
- Psoas and capsule hypertrophy
- Adductor, rectus and hamstring shortening
3 anatomical landmarks for the femoral component of TKA
- Whitesides (90 to)
- Epicondylar axis
- Posterior condylar axias (ER 3 degrees)
How does a pediatric patient differ regarding trauma ressuciation
- large head - spine board cutout
- higher cervical injury with neuro damage
- higher C1-3 injury
- spleen and liver outside rib cage
- lower blood volume - high HR, low BP
- higher porportional surface area - hypothermia
- elastic rib cage - more thoracic trauma
- strong ligaments; weak bones - low chance of pelvic ring injury
- anterior trachea - no need for cuff in ETT
Three biomechanical effects of the Latarjet (3)
- Sling concept from conjoint tendon
- De-function pec minor
- Bony block increases articular arc
- Capsular reinforcement
- Bony autograft for defect
4 components of the syndesmosis
Anterior-inferior tib-fib ligament
Posterior-inferior tib-fib ligament
Intraosseous membrane
Intraosseous ligament
Inferior Transverse ligament (with PITFL)
Differential diagnosis for lytic lesion in the proximal phalanx
- enchondroma
- ABC
- GCT
- UBC
- brown’s tumor
- EG
- infection
- NOF
3 ways to avoid varus in a subtroch femur fracture
Medial start point: Nail will not reduce your fracture
- Piriformis entry nail
- Lateral nailing
- Abduct the body
Clamp or k-wire the reduction
Fixed angle plate (95 blade or PFLP)
Long term complications of radiation for sarcoma treatment
Sarcoma
Pathological fracture
Joint contracture
Muscle atrophy
Limb length discrepancy
Prognosis of poor predictors of Type II Odontoid
> 5 mm displacement (>50% nonunion rate)
fx comminution
angulations > 10 degrees
age > 50 years
delay in treatment
Risk factors for neurological deterioration of vertebral OM
- elderly
- diabetes
- MRSA (aggressive pathogen)
- associated abcess
- cervical level
- late diagnosis
Changes that muscles undergo during endurance training
- contractile muscle adapts by increasing energy efficiency
- increases in mitochondrial size, number, and density
- increases in enzymes involved in Krebs cycle, fatty acid processing, and respiratory chain
- over time, increased use of fatty acids > glycogen
- over time, oxidative capacity of Type I, IIA, and IIB fibers increase
- percentage of more highly oxygenated IIA fibers increases
- Aerobic Threshold: level of effort at which anaerobic energy pathways become significant energy producer
- Anaerobic (lactate) Threshold: level of effort at which lactate production > lactate removal
*False positive for Thesaly test
Multiple knee injuries
Hx of knee surgery
OA
Articular cartilage injuries
Neurodegenerative disorders
*Stages of perilunate dislocation
SL disruption (ligament vs. transscaphoid)
Lunocapitate disruption
Lunotriquetrial disruption
Lunate dislocation
What are you blocks to reduction in DDH (7)
psoas
adductor tendon
labrum
capsule
hypertrophied teres
pulvinar
transverse acetabular ligament
What are the 4 types of neural tube defects
-
spinal bifida oculta
- defect in vertebral arch with confined cord and meninges
-
meningocele
- protruding sac without neural elements
-
myelomeningocele
- protruding sac with neural elements
-
rachischisis
- neural elements exposed with no covering
Describe requirements of informed consent?
- Competent patient
- Disclosure of all relevant risks and alternative
- Free or coercion/voluntary
Abnormalities associated with the spinal anatomy in dysplastic spondylolisthesis
hypoplastic facets
maloriented facets
sacral beaking
abnormal pars development (leads to elongation and slippage)
Name five modifiable risk factors (non-medication) for osteoporosis
- Smoking
- Impact exercise
- Diet high in calcium 1-1.2g/day and vitamin d/sunlight exposure
- EtOH - > 2 units/day
- Low BMI
- Estrogen deficiency
Etiology of groin pain after THA
- infection
- psoas impingement
- aseptic loosening
- stress fracture
- pseudotumor
- GT impingement
*Risk factors for femoral neck fracture in hip resurfacing?
notching of the femoral neck
osteoporotic bone
large areas of pre-existing osteonecrosis
femoral neck impingement (from malaligned acetabular component)
female sex
varus positioning of femoral component
*Complications associated with tibial tuberosity fixation?
-
Recurvatum deformity
- more common than leg length discrecancy
- growth arrest anteriorly as posterior growth continues leading to decrease in tibial slope
-
Compartment syndrome
- related to injury of anterior tibial recurrent artery
- Loss of range of motion
-
Bursitis
- due to prominence of screws and hardware about the knee
- Skin Necrosis
Radiologic assessment of femoral shaft fracture reduction (3)
- LT contour compared to uninjured side
- Cortical width/diameter
- Cortical thickness
- C- arm true lateral of femoral neck and other with posterior condyles aligned (differences in inclination of the position of the C-Arm reflects angle of anteversion of femoral neck)
- Post op CT scan - femoral malrotation using limited cuts through proximal and distal femurs (femoral neck and posterior condyles)
- Compare lines tangential to these to assess rotation
Risk factors for SMA syndrome following scoliosis
- Smaller (shorter, weight less)
- Rigid curve on lateral bend
- Lenke lumbar modifier B, C
- Staged procedure
- Low BMI
*Classes of Shock (Usually specifically about class IV)
-
I < 15%
- <750ml blood loss
- BP normal
- > 30 mL/hr
- HR normal
- Anxious
-
II 15% to 30%
- (750-1500ml)
- > 100 bpm
- BP normal
- 20-30 mL/hr
- pH normal
- confused, irritable, combative
-
III 30% to 40%
- (1500-2000ml)
- > 120 bpm
- decreased BP
- 5-15 mL/hr urine
- acidoditc
- lethargic
-
IV > 40% (life threatening)
- (>2000ml)
- > 140 bpm
- decreased
- negligible uring
- acidotic
- coma
Conditions associated with dural ectasia
- Marfans
- Neurofibromatosis
- Ehuler Danlos
- Osteogenesis Imperfecta
- Ankylosing Spondylitis
Relative contraindications to total joint arthroplasty?
Neurologic disorder
Previous infection (osteo)
Neuropathic
Poor medical status
Dementia
Complications of OM in a pediatric patient
-
DVT
- is an infrequent complication
-
risk factors
- CRP > 6
- surgical treatment
- age > 8-years-old
- MRSA
- Meningitis
- Chronic osteomyelitis
- Septic arthritis
- Growth disturbances
-
Limb-length discrepancies
- may result in gait abnormalities
- Pathologic fractures
*Determinants of skeletal growth remaining
- < 12 y
- Tanner stage (< 3 for females)
-
Risser Stage (0-1)
- Risser 0 covers the first 2/3rd of the pubertal growth spurt
- correlates with the greatest velocity of skeletal linear growth
- open triradiate cartilage
- open olecranon physis
- timing of menarche
- hand XR
Varus malunion in femoral neck fracture, clinical findings?
- Decreased ROM
- LLD
- Abductor lurch
- Trendelenburg sign
- Prominent GT
What are radiological risk factors for development of SCFE
- Posterior slope angle >14
- vertical physis
- retroverted head
- protrusio
*4 things that lead to bad prognosis in pediatric radial head fracture
- Open management
- Internal fixation
- AVN
- Synostosis
- > 3 mm translation
- >45 angulation
- Malunion
- <60 deg of motion following reduction
Risk factors for radioulnar synostosis
Comminution
Proximal third of both bones
Same level fractures
IOM injury
Severe soft tissue disruption
Head injury
Boyd approach
Delayed management
Bone in IO space
Onlay graft
Hardware in IO space
*Measures of adequate resusitation
- MAP > 60
- HR < 100
- urine output 0.5-1.0 ml/kg/hr (30 cc/hr)
-
serum lactate levels
- most sensitive indicator as to whether some circulatory beds remain inadequately perfused (normal < 2 mmol/L)
- gastric mucosal ph
- base deficit
- normal -2 to +2
- pH < 7.24
What are the components of the DRUJ?
-
TFCC made up of
- dorsal and volar radioulnar ligaments
- deep ligaments known as ligamentum subcruatum
- central articular disc
- meniscus homolog
- ulnar collateral ligament
- ECU subsheath
- origin of ulnolunate and ulnotriquetral ligaments
- dorsal and volar radioulnar ligaments
-
DRUJ Stability - TFCC has elements that converge to this, so you need to repair it first when you have instability
- Primary - moves in the direction of the palm
- One will act as a buttress, one will act as a check rein, so we don’t really know which one is more important
-
volar radioulnar ligaments
- volar translation
- supination
-
dorsal radioulnar ligaments
- dorsal translation
- pronation
- trigangular fibrocartilage
- Secondary
- ulnar head
- sigmoid notch
- interosseous membrane
- pronator quadratus
- Primary - moves in the direction of the palm
Radiographic evidence of syndesmotic injury
medial clear space > 4mm
tib-fib clear space > 6mm
tib-fib overlap < 1mm on mortise
Spinal findings in achondroplasia
-
lumbar spinal stenosis
- caused by short pedicles
- most likely to cause disability
-
thoracolumbar kyphosis
- may cause neurologic symptoms
-
foramen magnum and upper cervical stenosis
- may cause periods of apnea
Three ways to avoid patellar maltracking
- Avoid internal rotation of the femoral prosthesis
- use the transepicondylar axis
- use the posterior condyles with 3 deg ER
- lateralization of the femoral component
- internal rotation of the tibial prosthesis
- medial 1/3 of the tibial tubercule is your landmark
- placing the patellar prosthesis lateral on the patella
anatomic reasons for pseudosubluxation
- horizontal facets
- hyperlaxity
- poor motor control
4 non-skeletal features of fibrous dysplasia
-
Commonwith polyostotic
- Hyperthyroidism
- Hypophosphatemia
- Acromegaly
- hyperprolactinemia
- Café au lait spots (McCune Albright - coast of maine)
- Precocious puberty (McCune Albright)
- Eye deviation and blindness (Chereubism)
- Cranial abnormalities (Chereubism)
4 types of SLAP tears
- I - Labral and biceps fraying, anchor intact
- II - Labral fraying with detached biceps tendon anchor
- III - Bucket handle tear, intact biceps tendon anchor (biceps separates from bucket handle tear)
- IV- Bucket handle tear with detached biceps tendon anchor (remains attached to bucket handle tear)
- V - SLAP lesion and anterior labral tear (Bankart lesion)
- VI- Superior flap tear
- VII- SLAP lesion with capsular injury
*3 causes for RA patient not to extend 4/5th digits
- Caput Ulnae Syndrome
- Vaughn- Jackson Syndrome (attritional rupture of EDQ only)
- MCP dislocation
- Sagital band attenuation
- PIN palsy
Describe the leadbetter maneauver
- Flex the hip to 90, pull axial traction
- relaxes hip musculature
- IR to 45 degrees
- relaxes Y ligament
- Extend and slightly abduct the hip maintaining IR and traction
Principles of medical ethics
- Respect for autonomy - the patient has the right to refuse or choose their treatment
- Beneficence - a practitioner should act in the best interest of the patient
- Non-maleficence - “first, do no harm”
- Justice - concerns the distribution of scarce health resources, and the decision of who gets what treatment (fairness and equality)
- Respect for persons - the patient (and the person treating the patient) have the right to be treated with dignity.
- Truthfulness and honesty - the concept of informed consent has increased in importance since the historical events of the Doctors’ Trial of the Nuremberg trials and Tuskegee syphilis experiment.
*4 long term complications of radial head fracture in adults
- Elbow stiffness
- Heterotopic Ossification
- Concurrent injury
- Recurrent surgery
- Delay to surgery
- Prolonged immobilization
- PIN Palsy
- Ulnar nerve injury
- Infection
- Instability
- Elbow OA
- Fracture displacement
Borders of the triangular space
long head triceps
teres major
teres minor
This healthy patient had a fall from height onto a plantar-flexed foot. What are the key things you need to look for on XR?
five critical radiographic signs that indicate presence of midfoot instability
- disruption of the continuity of a line drawn from the medial base of the second metatarsal to the medial side of the middle cuneiform (diagnostic of lisfranc)
- widening of the interval between the first and second ray (may see a fleck sign diagnosic of lisfranc)
- medial side of the base of the fourth metatarsal does not line up with medial side of cuboid on oblique view
- metatarsal base dorsal subluxation on lateral view
- disruption of the medial column line (line tangential to the medial aspect of the navicular and the medial cuneiform)
Don’t forget WB or stress veiws if you have concerns and there is nothing obvious on XR
Structures of the PLC
-
Static structure - is what you will reconstruct during injury
- LCL
- Attaches 8mm behind the most anterior fibula
- Politeus tendon with popliteofigular ligament
- Inserts 18.5mm distal, anterior and underneath LCL on the tibia
- Popliteofibular ligament
- Lateral capsule
- Arcuate ligament
- Fabellofibular ligament
- LCL
-
Dynamic
- Biceps femoris (inserts posterior to LCL on fibula)
- Popliteus
- Iliotibial tract
3 ways to assess adequate femoral neck reduction
- Restoration of Shenton’s line
- S- curve on all views (head-neck jxn) – never a c-curve (Rockwood and Green’s)
- Garden Alignment Index (Rockwood and Green’s)
- AP: medial trabeculae:medial femoral cortex 155-180 degrees
- Lateral: central trabeculae in head:neck 155-180 degrees
+Deformities associated with CAM (radiographic)
decreased head-to-neck ratio
aspherical femoral head
decreased femoral offset
femoral neck retroversion
Indications for scaphoid ORIF
- Proximal pole fracture
- Displaced scaphoid fractures
- 1 mm displacement
- SL angle > 60
- RL angle > 15
- Intrascaphoid angle > 35
- Associated perilunate
- Multipy injured patient
- Comminution
- DISI > 15 degrees
Describe mechanism of proximal tib-fib dislocation. Features on exam, reduction mechanism and treatment?
- Mechanism: Twisting of flexed knee (athletic injury)
-
Physical Exam:
- Prominent lateral mass
- Pain worse with ankle DF (proximal fibular migration)
- Pain worse with knee extension
- Examine stability at 90 degrees (relaxes LCL)
- Translation of prox fibula
- Peroneal nerve
- Ankle exam
- LCL and PLC instability to rule out other injuries
-
Closed Reduction:
- Flex btw 80-110 to relax LCL
- Reduce opposite direction of dislocation
- immobilize for 3 weeks (controversial)
-
Open Reduction:
- Screw with repair of joint capsule
- immobilize for 6 weeks
- remove in 12 weeks
-
Chronic Dislocation
- usually non-op with activity modificaiton and strap
- arthrodesis with mid-fibular resection is an option in older patients
- attempts have been made to use the IT or biceps to create a sling for the head of the fibula
- Results are improved with LCL/PLC pathology and repair
Note that actue and chronic entities are two seperate issues and should be treated differented. The IT band can be use
Anatomy of the DRUJ with scope
- Fibrocartilage
- can debride 80% without causing instability
- Radial and ulnar insertions of the radioulnar ligaments
- can stress them and assess for instability
- ECU sheath?
- sometimes used to teather a TFCC repair to
Deformities associated with Pincer - descriptive, not measurements
anterosuperior acetabular rim overhang
acetabular retroversion
acetabular protrusio
coxa profunda (deep socket)
Reasons for lack of extension post-op ACL
- lack of extension pre-op
- post-op arthrofibrosis
- cyclops lesion
- anterior tibial tunnel placement
- tighten in flexion
Measurements indicating normal c-spine alignment
-
Lateral view
- Basion Dens Interval (BDI)
- Anterior spinolaminar line < 1mm
- Drawn from opisthion to C1 arch, should pass C1/C2
- ADI < 3mm
- Posterior cortex of atlas should be parallel to anterior cortex of axis
- SAC > 13mm
-
Open mouth
- Joint articulations should be
- Combine overhang < 7mm
What are 4 major and 4 minor criteria for fat emboli syndrome
-
Major (1)
- hypoxemia (PaO2 < 60)
- CNS depression (changes in mental status)
- petechial rash
- pulmonary edema
-
Minor (4)
- tachycardia
- pyrexia
- retinal emboli
- fat in urine or sputum
- thrombocytopenia
- decreased HCT
-
Additional
- PCO2 > 55
- pH < 7.3
- RR > 35
- dyspnea
- anxiety