HY Flashcards
Discoid Meniscus
What is the histopathology?
whats the more common side?
Diagnosis?
Whats the wrisberg variant?
tx for failured conservative mgmt.
why more prone to tearing?
decreased type I collagen fibers in a disorganized circumferential course
Lateral meniscus more common than medial meniscus, bilateral in 20% of cases
Xrays: squaring of lateral femoral condyle, cupping of lateral tibia plateau
Diagnosis: presence of meniscus on ≥3 consecutive sagittal MRI images (“bow-tie sign”)
Wrisberg variant (type 3): lacks posterior meniscotibial attachments, treat w/ repair & creation of posterior meniscotibial attachments
Failed conservative treatment: arthroscopic saucerization & repair
Discoid meniscus 3-5% general population, ¼ bilateral of those with discoid. Discoid menisci are more prone to tearing than are normal menisci, and instability may result because of a lack of normal meniscal-capsular attachments. Discoid lateral menisci are thicker and have less vascularity of the peripheral meniscus than normal menisci. Discoid menisci also cover a larger surface area of the tibial plateau than normal and may cover the entire lateral plateau. Discoid menisci have a decreased number of collagen fibers with a more disorganized course relative to normal menisci. Intrameniscal mucoid degeneration is also common. It is believed that the disorganized circumferential network of collagen in discoid menisci weakens the ultrastructure of the meniscus and predisposes it to tearing. Torn menisci cause knee pain, popping and snapping, a limp, and possibly a loss of terminal extension. Menisci are formed with type I collagen, not type II collagen.
Achondroplasia
gene mutation?
spine abnormalities?
What test must me obtained?
type of dwarfism?
fibroblast growth factor receptor-3 (FGFR3) gene resulting in abnormal phosphorylation of selected tyrosine residues by upregulated tyrosine kinase activity. This results in endochondral ossification irregularities and rhizomelic shortening of limbs. It is the most common skeletal dysplasia, with an incidence of approximately 1 in 30,000 live births. Global spinal stenosis due to abnormally short and thickened pedicles as well as a decreased interpedicular distance is a consequence of achondroplasia, and many patients require surgical decompression and fusion for this issue. However, of particular significance in early life is the possibility of foramen magnum stenosis with brainstem compression. There is a significantly increased early mortality in the achondroplastic population due to this, and prompt recognition and treatment is essential. The diagnosis can be challenging in infants, and the orthopaedic surgeon should be aware of any signs of chronic brainstem compression such as apnea, lower cranial nerve dysfunction, swallowing difficulties, snoring, hypotonia or paralysis, or upper motor neuron signs in the arms and legs.
Diagnosis is made by an MRI scan of the brain and cervical spine, and treatment is decompression. Thoracolumbar kyphosis is common in individuals with achondroplasia and often resolves with time and improved truncal strength. While this rarely requires surgical intervention for progressive kyphosis with spinal cord impairment, thoracolumbar spinal cord compromise does not explain this patient’s symptomatology. Cardiac abnormalities and abnormal brain electrical activity similarly do not address the primary symptomatology and clinical concern in this patient.
How do bisposponates work
Bisphosphonates inhibit osteoclastic bone resorption. Bisphosphonates attach to hydroxyapatite binding sites on bony surfaces, especially surfaces undergoing active resorption. When osteoclasts begin to resorb bone that is impregnated with bisphosphonate, the bisphosphonate released during resorption impairs the ability of the osteoclasts to form the ruffled border, to adhere to the bony surface, and to produce the protons necessary for continued bone resorption. Bisphosphonates also reduce osteoclast activity by decreasing osteoclast progenitor development and recruitment and by promoting osteoclast apoptosis.
what is the dominant blood supply in
In children until about age 4, the primary supply to the proximal femoral physis arises from the posterosuperior branch to the lateral cervical ascending artery, which comes from the medial femoral circumflex artery.
The lateral femoral circumflex artery does not contribute a significant amount to the epiphyseal blood supply, and the artery of the ligamentum teres provides up to 20% of the blood supply to the head, increasing from age 8 into early adulthood and then declining. Schematic for this is shown in Figure 1. The artery of Adamkiewicz supplies the spine. The blood supply is relevant, as it means a piriformis starting site for a femoral nail puts the pediatric patient at increased risk of avascular necrosis of the femoral head and is thus contraindicated.
when to decide to performe selective thoracic fusion AIS
what’s the ratio to look for? How to calcuate it? What are 2 other factors?
Selective thoracic fusion is indicated for patients who have primary thoracic curvatures (Lenke type 1 and 2 curves) with flexible lumbar curves. The most critical determinant of whether or not a selective thoracic fusion will be successful is an **apical vertebral translation ratio >1.2. **The apical vertebral translation ratio is defined as the distance between the C7 plumb line to the apex of the thoracic curve divided by the distance between the center sacral vertical line and the apex of the lumbar curve. Thus, thoracic curves that are translated >20% farther than the lumbar curve from their respective midlines are better candidates for selective thoracic fusion and are less likely to have residual deformity after fusion. Other factors for determining whether or not selective thoracic fusion is likely to succeed include a lumbar curve <45° and lumbar curves that bend out to <25.
Scapula Fx
associated with?
non-op tx is?
Operative indications?
Most common approach is what interval?
ST disociation: outcome dependent on? most often associated with? what to do if neuro function unlikely?
Clavicle Fx
ossification?
Scapula ER prevents?
Sling vs figure 8?
Predictors of nonunion? Biggest risk factors?
Nonoperative vs Operative?
Outcomes Decreased ?? if ??, equal ??
Patella Fx
main blood supply enters the patella from?
Strongest construct?
Partial patellectomy: Indicated for? What kind of TKA is contraindicated? What can happen after?
Most common complications 1 and 2
Humeral Shaft Fx
Holstein lewis risk of neuropraxia?
When does radial nerve palsy usually recover?
Mobility at 6 weeks associated with?
Heavier patients increased risk of?
Iatrogenic nerve injury dependent on?
ORIF with plate for?
Full crutch weight bearing is ?
Anterior vs Posterior approaches?
If cable or wire fixation: where do you want fixation?
Acceptable alignment can be obtained within the following parameters: <3 cm of shortening, <30° of varus or valgus angulation in the coronal plane, and <20° of angulation in the sagittal plane.
Humeral Shaft - IMN
IMN nail is best for?
IMN vs ORIF?
Risk of nerve injury with what interlock?
Radial nerve locations:
From top of HH?
Crosses posterior humerus ? cm from medial epicondyle?
Crosses lateral IMS ? cm above lateral epicondyle and ? cm proximal to RC joint?
What interlock puts the msk nerve at risk?
humeral shaft nonunion
non-op nonunion rate? Operative nonunion rate?
nonunion after non-op surgery?
Non-op NU rate: 2-33%, Operative NU rate 5-10% Vitamin D deficiency is major metabolic risk factor for nonunion
radial nerve palsy after humeral shaft fx
resolution by ?
when to get emg?
whats the first muscle to fire? last muscle?
Radial nerve palsy
Closed humeral shaft: likely radial nerve neuropraxia → Observation 90% resolve by 3 months; if not → EMG
Surgical exploration if not improved over 4-6 months
Open humeral shaft: likely radial nerve neurotmesis → exploration & repair
Brachioradialis is first muscle to recover (wrist extension in radial deviation), followed by ECRL; extensor indicis proprius (EIP) is last (index finger MCP hyperextension).
Terrible Triad
mechanism?
order of surgery?
orif vs replace radial head?
coronoid tx?
LCL tx?
MCL repair?
If only LCL repaired splint in ? If MCL and LCL repaired splint in?
ROM post op?
Coronoid Fracture
what inserts here?
what kind of instability?
Anterior bundle of MUCL inserts on sublime tubercle (anteromedial facet of coronoid)
Fracture of anteromedial facet and/or injury to anterior bundle → varus instability, varus posteromedial rotatory instability (LCL usually also torn)
Immobilization & early ROM if stable elbow joint ORIF if unstable elbow joint
HO ppx for acetabular fxs?
radiation treatment with a single dose between 700 and 800 cGy within 72 hours of surgery.
Data currently do not support the use of nonsteroidal anti-inflammatory drugs (NSAIDs) for prevention, and long-term use of NSAIDs has led to acetabular nonunion.
Currently, sufficient literature indicates that NSAIDs are ineffective as prophylaxis for HO after acetabular fracture surgery. Three randomized controlled trials comparing the effects of indomethacin with those of a placebo demonstrated no differences in the incidence or volume of HO. Timing of XRT is critical, and the treatment has risks and relatively high costs. Ample evidence supports the administration of XRT within 72 hours after surgery. One study showed that in patients who received XRT within 3 days, the reported incidence of clinically significant HO was 10%, whereas in those receiving XRT ≥21 days postoperatively, the reported incidence was 92%. Surgical removal of HO has improved outcomes and has led to lower recurrence rates, even when performed before complete maturation. However, advances in prophylaxis are needed to prevent this disease.
Capitellar fx
coronal shear fx:
whats the exposure?
most common complication?
what can lead to AVN?
LUCL disruption leads to?
Capitellar fracture Coronal shear fracture of capitellum with extension into trochlea (double arc sign): requires exposure of entire lateral column, elevating off common extensors & capsule
Most common complication: stiffness (flexion contracture)
Disruption of posterior perforating vessels → AVN of capitellum
Disruption of LUCL → valgus posterolateral rotatory instability
Olecrannon fxs
tension band only if?
most common complication?
Penetration of k-wire through anterior (trans) cortex of can lead to?
Elderly patient with communited, osteoporotic bone?
HO associated with?
simple transverse tension band, otherwise ORIF
Most common complication is symptomatic implants (40-80%)
Penetration of K-wire through anterior (trans) cortex of ulna → AIN injury & mechanical block to pronosupination ➢Obs x 6 months or can explore if suspect injury or obvious hardware prominence
Elderly patient with comminuted, osteoporotic bone: excision with triceps advancement (if fracture involves less than 30-50% of articular surface) Can also treat non-op with cast
Heterotopic ossification associated with elbow fractures is higher in patients with closed head injury HO prophylaxis:
* Indomethacin
* Single radiation (700cGy dose): either 4 hours before or within 72 hours after surgery
Olecranon fx after low-energy fall in kids: think osteogenesis imperfecta
Distal Femur fx
golf club deformity is caused by?
what is the strongest construct for extra-articular fxs?
whats the deformity for supracondylar fxs?
WB post op after ORIF?
most common reason for failure?
open fracture
Tetanus?
OR in 6 vs 6-24 hrs?
GA classification best after?
GA I-III
Abx with in ? hrs.
I &II get
III gets?
Farm injuries?
Water contamination?
Irrigation with?
Abx 1-3 hrs
Cephalosporin I and II, add gent for III, PCN for soil, FQ for water
(or Ceftriaxone alone for type III)
stop 24 hrs of wound closures
flap w/in 7 days improves outcomes, decreases reoperation rate
Normal saline best over soap, abx solution
use counter incisions and wound vacs
masquelet technique
good for defects?
membrane forms?
optimal timing?
PMMA abx spacer: highest abx concentration at 24 hrs, level remain bactericidal for 4 months.
Vanc vs tobra
max concentration of vanc?
Posterior pelvic ring injuries are most often associated with
transverse-oriented and associated both-column acetabular fracture patterns. When evaluating a high-energy acetabular fracture, it is important to be vigilant in assessing for ipsilateral sacroiliac joint disruptions
tibial shaft fx
- IMN start point?
- Proximal 3rd fx deformity? rate of malunion?
where to place blocking screws? what are other ways to counteract the deformity intra-op? - supra vs infra approach?
- paterall split vs paratendinous?
- IMN start point too lateral? too medial?
- SPRINT trial showed?
- risk factors for nonunion requiring reoperation?
tibial shaft fx
- Disruption of proximal tib-fib joint w/ shaft fx is a poor prognostic factor:
- Provisional plating to aid tibial IMN:
- Distal-third fxs: keys to know?
- isolated tibial shaft fx w/ intact fibula leads to?
- dropped hallux after tibial IMN?
- Proximal tibial liss plate?
- Soft tissue coverage of leg: proximal, middle, distal?
- distal tibial non-union, what approach to use?
63% incidence of open fx, 36% CPN injury (70% of which don’t recover from time of injury), 29% compartment syndrome
avoid anteromedial incision → risk of wound breakdown
where is the radial nerve found in relation to the
* lateral epicondyle
* medial epicondyle
* triceps aponeurosis
nerve crosses the posterior aspect of the humerus
14 to 15 cm proximal to the lateral epicondyle
20 to 21 cm proximal to the medial epicondyle
4 cm (or two fingerbreadths) proximal to the point of confluence of the triceps aponeurosis and the long and lateral heads of the triceps.
However, in trauma cases where the anatomy is distorted by comminution and fracture displacement, a different method may prove to be more reliable. In 2012, Seigerman and associates found in a cadaveric study that the radial nerve reliably is found approximately 4 cm (or two fingerbreadths) proximal to the point of confluence of the triceps aponeurosis and the long and lateral heads of the triceps.
Proximal Humerus fx:
- 1 part non op outcomes?
- predictors of HH ischemia?
- hemiarthroplasty for?
- most common complication? How to prevent varus collapse?
Proximal Humerus
- rTSA in elderly: importance of GT repair? Guidance for implant? What to avoid post op?
- outcomes of ORIF vs TSA depend on? Poor outcomes if?
- isolated GT fx?
- Malunion of proximal humerus fx: whats the deformity and tx?
- Nonunion: most common in? tx options?
distal humerus fracture in elderly
TEA vs ORIF
distal humerus fx?
chevron osteotomy:
* How to angle screw?
* most common complication?
* what nerve is at risk?
Post op ulnar neuropathy associated with?
ORIF: most common complication? Don’t remove hardware until? How to improve flexion?
Radial nerve is typically found ?cm proximal to triceps apponeurosis.
Isolated lateral/medial condyle: immobilize in?
Monteggia fx:
apex of ulna fx in relation to radial head dislocation?
What type is associated w/ worse complication rate and outcomes?
what nerve is at greatest risk? How will injury to it present?
radial head fx
ORIF if?
what’s the safe zone for plating? position of arm when plating?
Kocher vs kaplan aproaches: NV interval, risk?
What do do for comminuted fxs? What are associated risks of this pattern?
Lateral approaches to forearm, how to rotate the arm to protect PIN?
Post-traumatic elbow stiffness gets?
Adult BBFx
isolated ulna non op if?
objective of ORIF is to restore?
Best Plate, why? when is ROH ok?
Bone grafting?
Bridge plate osteosynthesis, construct is?
Distal radius fx
acute CTS %?
Normal tilt, radial height, inclination?
New recs for non op vs op?
CRPS prevention? types? RF?
EPL rupture and tx?
Most common 1 & 2 ruptures after ORIF?
Predictors of DRUJ instability?
Dorsal bridge plate can tolerate axial load of?
DRUJ injury?
DX dx?
Position of ulna in pronation vs supination?
Galeazzi fx: what can me interposed? what’s a high risk of DRUJ instablity?
DRUJ is most stable in??
DRF + ulnar styloid + DRUJ instablity: tx strategy?
If DRUJ stable?
If DRUJ unstbale
TFCC has 7 components, whats the most import stablizer to the DRUJ?
Faith trial:
SHS vs CRPP?
risk factors for revision?
FNF elder sedentary
regional nerve block has been shown to?
what if they can’t get MRI if nondisplaced suspected?
Best predictor of post op mortality?
Chronic RF associated with?
Factors influencing independent ambulation and live independently at 1 year?
Cement fixation?
FNF in octogenarian?
femoral shaft fx
femoral neck fx: pattern? how to identify and operative strategy?
Each femoral shaft fx can lose up to ? of blood?
Fat embolism syndrome: biochemical theory
antegrade IMN associated with what weak muscle groups?
femoral shaft fx
piriformis entry: risk of iatrogenic fx? deformity if piriformis nail used for troch entry?
Most common complication after IMN: how to assess?
femoral shaft fx
tx of nonunion
shortening deviates mechanical axis? Lengthening does?
open vs closed reduction with IMN?
complications: antegrade vs retrograde?
most common peds complication after IMN nail?
RF for nonunion
Knee dislocation
associated with lateral vs medial dislocation?
Which direction if most common? 2nd most common? and associated injury pattern?
SPN vs DPN injury findings?
Popliteal artery %? peroneal injury %?
acute tx of ligamentous injuries associated with?
acute vs delayed treatment?
Dimple sign associated with?
Multilig knee injury: early arthroscopy increased risk for?
Knee joint challenge: how many cc’s needed?
Most common complication after ligamentous reconstruction?
Tibial Plateau fx
- lateral plateau fracture depression of ? associated with_?_
- Type IV associated with ?
- associated mensicus tear?
- Primary vs secondary goal
- timing of ORIF after fasciotomy
- best bone graft substitute?
- risk factors for infection?
- hybrid external fixation on test? (distractor, but what do know about it?)
- good outcomes w/ non op if?
- plateau fx in setting of osteoporosis & existing DJD?
- TKA after tibial plateau fx asscoiated with?
- best predictor of arthrofibrosis after ORIF?
- Tib plateau w/ or w/o soft tissue injuries injuries?
- Prolonged postop NWB protocol →
- Subchondral insufficiency fracture of knee (distal femur, tibial plateau):
- Hyperextension bicondylar tibial plateau (HEBTP) fracture pattern:
- Predictors of compartment syndrome:
compartment syndrome
highest risks?
Dx?
tibial fx w/ cs have increase risk of?
Dual vs single incision?
exertional compartment syndrome: pressures rest, 1 min, 5 minutes? Recurrence is secondary to?
Pilon fx?
3 main fragents?
chondrocyte: injury and where?
ex-fix: acute fibula fixation? pin care?
Brake time after ORIF?
what is concerning for syndesmotic fx?
fine wire ring fixation for pilons associated with?
cal fx
what is the constant fragment, ligaments that attach here? What structure is at risk and when?
ST OA w/ loss of calc height: next steps?
if fixed and calc is wide, patients get?
most common acutre concurrent pathology w/ fx?
better outcomes after orif?
