General Flashcards
What to avoid when treating fibrous dysplasia lesion?
Autograft - quickly turns into FD
Soft tissue sarcoma that metastasizes to the retroperitoneum?
Liposarcoma (order CT abd/pelvis in addition to chest)
MC Sarcoma of the hand/wrist?
Epithelioid
4 negative prognostic factors for soft tissue sarcoma?
High grade, mets, > 5 cm, deep
Most locally aggressive of all benign soft tissue tumors?
Extra-abdominal desmoid
Immunohistological marker for desmoid tumor?
Estrogen receptor beta
MC location of alveolar cell sarcoma?
Anterior thigh
Key difference b/t hematoma and spontaneous bleeding from sarcoma?
Lack of fascial plane tracking and subQ ecchymosis with sarcoma due to pseudocapsule
Origin of chordoma?
Notochord tissue
MC location of hemangioma involving bone?
Vertebral body
What is POEMS syndrome
Polyneuropathy, Organomegaly, Endocrinopathy, M-protein, and Skin changes
Classic triad of Hand-Schuller-Christian Disease?
Exophthalmos, DI, and Lytic skull lesions
5 MC carcinomas that metastasize to bone?
BLT and a Kosher Pickle (in order)
2 types of tissue found in periosteal osteosarcoma?
Cartilage and bone
Key features of Mafucci syndrome?
Soft tissue angiomas and enchondromas
2 benign bone tumors that metastasize to lung?
GCT and chondroblastoma
Substance produced by clear cell sarcoma cells?
Melanin
MC epiphyseal lesion in immature pt?
Infection (not neoplasm)
Immunohistochemical stain for benign and malignant vascular tumors?
CD34 and CD 31
5 parts of stance phase?
Initial contact, loading response, midstance, terminal stance, and preswing
Classic gait pattern for ACL deficient knee?
Quad avoidance gait
Gait pattern in pts with hemiplegia?
Prolongation of stance and double limb support
Problem with too soft prosthetic heel?
Excessive knee extension
Time for maximal spontaneous recovery from stroke? TBI?
6 mos.; 12-18 mos.
Amount of gait cycle spent in double stance phase?
12%
Amount of body’s center of gravity displaced during gait?
5 cm vertical, 6 cm lateral
Last functional level in which tetraplegic pts can function independently?
C6
This functional level allows community ambulation with AFO?
L3
Axes for plotting ROC curve?
X=1-specificity, Y=Sensitivity
Definition of discrete data? Categorical data?
Infinite # of poss. values (e.g height, time, etc.); finite # poss. values (e.g. male/female)
Transcription factor that directs mesenchymal cells to osteoblasts?
Runx2
Wolff’s Law?
Remodeling of bone occurs in response to stress (e.g. space travel)
Heuter-Volkman Law?
Remodeling occurs in small packets of cells - compression inhibits growth, tension stimulates it
What % of cardiac output goes to bone?
5-10%
Major source of nutrition of the growth plate?
Perichondral artery
3 types of bone formation and example of disease associated with each?
Enchondral - achondroplasia; Intramembranous - cleidocranial dysostosis; Appositional - Paget’s dz
Primary mechanism of rejection to allograft bone?
Cellular
Signal via serine-threonine kinase receptors?
BMP, TGF-B
Signal through tyrosine kinase receptors?
IGF-II, PDGF
Optimal radiation dose to prevent HO s/p THA?
600-700 rad/5 Gy
Typical radiation dose for treatment of STS?
60-70 Gy
Definition of + likelihood ratio?
Sensitivity/1-specificity
Definition of - likelihood ratio?
1-sensitivity/specificity
Study design for determining RR? OR?
Cohort; case-control
Definition of NNT?
1/ARR
What is clubbing a sign of?
Metastatic bone cancer
Size cut-off for staging STS according to AJCC? Bone tumors?
5 cm; 8 cm
3 soft tissue sarcomas that can show calcification?
Synovial cell, liposarcoma, and angiosarcoma
Causes of vertebra plana?
MELT: mets/myeloma, EG/Ewings, leukemia/lympohoma, trauma/TB
2 bone dysplasias associated with retinal detachment?
Kneist syndrome and SED
2 bone dysplasias that are AR?
Diastrophic dysplasia and McKusick
2 bone dysplasias assoc. with C1-2 instability?
McKusick and Morquio syndrome
Dysplasia assoc. with dumbbell-shaped bones and joint contractures?
Kneist syndrome
Key difference b/t Turner and Noonan syndrome?
Noonan - normal gonadal development, MR, and more severe scoliosis
2 causes of biconcave “fish” vertebrae?
Sickle cell anemia and OI
2 causes of Erlenmeyer flask deformity?
Gaucher’s disease and osteopetrosis
Poor prognostic factors for return of function after brachial plexus injury?
No biceps after 6 mos and horner’s syndrome
Highly prognostic of ability to walk in pts with cp?
Ability to sit independently by age 2
Key functional level in spina bifida that allows independent ambulation?
L4 (quad)
Has been shown to prevent scoliosis and prolong walking in pts with DMD?
High-dose steroids
Key distinguishing feature b/t limb girdle and fascioscapulohumeral muscular dystrophy?
Normal creatine phosphokinase in FSCH, increased in LGD
What must screen for in pt with hemi-hypertrophy?
Wilm’s tumor (up to age 5)
Definition of a structural curve?
Largest curve + additional curves that fail to bend to < 25 deg
Rib vertebral angle cutoff for determining progression?
< 20 deg = low risk, > 20 = high risk
Key prognostic factor for impending rapid progression of spinal deformity in pts with NF?
Penciling 3 or more ribs
Where to stop fusion for Schuermann’s kyphosis (distally)?
1st lordotic disc/vertebra touched by sacral vertical line (vertical line extending from posterior body of S1)
Classic triad for Klippel-feil Syndrome?
Low hairline, webbed neck, and dec cervical ROM
Normal alpha angle?
60 deg (on coronal view), femoral head is bisected by line drawn down ilium
What other test must be considered in pt with H. influenza septic joint?
Lumbar puncture due to increased risk of meningitis
When genu varum naturally turns to genu valgum?
By 2.5 yrs
MC cause of bilateral genu valgum?
Renal osteodystrophy
Only inheritable long bone deficiency?
Tibial hemimelia (AD)
4 conditions assoc. with ball-and-socket ankle?
Tarsal coalition, absence of lateral rays, fibular deficiency, and leg length discrepancy
Most anterior structure on the anterior fibular head?
LCL
LCL origin relative to the popliteus insertion?
Superior and posterior
Order of insertion of structures on the proximal fibula (anterior to posterior)?
LCL, popliteofemoral ligament, biceps
Contraindication for distal patellar realignment?
Proximal arthrosis of the medial patellar facet
Contents of the rotator interval (4)?
Biceps, SGHL, caracohumeral ligament, and joint capsule
When to fix partial cuff tears (e.g. PASTA)?
> 7 mm exposed bone lateral to the articular surface
Objective test to help Dx CRPS?
3 phase bone scan
Leddy classification of Jersey finger?
I-retraction into palm, II-retraction to PIPJ, III-large bony fragment with little retraction
When to obtain CT scan in pt with concussion?
LOC > 5 min
2 key differences b/t SED and MED?
No spine involvement and disproportionate dwarfism with MED
MC cause of amenorrhea in female athletes?
Insufficient caloric intake
Mediates proximal to distal growth in the limb bud?
AER (FGF)
2 genetic conditions assoc. with syndactyly?
Poland and Apert syndromes
2 key feature of Poland syndrome?
Unilateral chest wall hypoplasia and sprengel’s deformity
MC type of thumb duplication?
Type IV - duplicated proximal phalanx
Ortho condition most likely to result in malpractice claim?
Femur fx (esp. in kids)
Mediates radial-ulnar growth in limb bud? Dorso-ventral axis?
ZPA (SHH); Wnt
Statute of limitations for most states?
2 years
Relationship of Ra (surface roughness) to fixation strength?
Linear
Torsional stiffness of an IMN? Bending stiffness?
R4; R3 if hollow, R4 if solid
Normal Bauman angle?
9-25 deg
Last ossification center to fuse in elbow?
Medial epicondyle
Tx of radial head/neck fxs?
60deg - ORIF
Power’s radio?
BC/AD
Primary shoulder restraint to inferior translation?
Coracohumeral ligament
Optimum crystallinity of PE?
45-65%
Maximal joint line elevation in TKA?
8 mm
Best way to Dx hypersensitivity rxn following THA?
Serum lymphocyte T-cell proliferation test (LTT)
Minimal PE thickness to prevent catastrophic wear?
8 mm
How to avoid damaging the saphenous n. when dissecting on the medial side of the knee?
Keep dissection anterior to sartorius
Indications for tibial tubercle transfer?
TT-TG > 20 mm
Primary stabilizer of the foot longitudinal arch?
Interosseus ligaments (not plantar fascia)
3 subtypes of Stage II PTTD?
IIA - hindfoot valgus without significant forefoot abduction; IIB - HF valgus with >40% talar uncovering; IIC - Fixed forefoot supination in addition HF valgus
Main blood supply to the talar head?
Artery of the tarsal canal
Most frequent fx in the body?
MC and phalanx
Amount of lengthening achieved with 30, 45, and 60 degree Z-plasties
25%, 50%, and 75%
2 key clinical signs of decreased digit perfusion after re-implantation?
Dec temp > 2 deg in 1 hour or temp < 30 deg
Factor most predictive of digit survival after replant?
Mechanism of injury
First sensation to be lost in compression neuropathy of UE?
Light touch with SW monofilament
Most important prognostic factor for nerve recovery after injury?
Age
Indicates expectant full recovery of obstetric brachial plexus plexopathy?
Biceps and deltoid muscle contraction by 2 mos of age
Key difference b/t JRA and RA with respect to hand PE?
Radial deviation of MCPJs in JRA
Oberlin’s transfer?
Transfer of ulnar n. fascicle of FCU to MC n. to help restore elbow flexion
Smith 3-5-7 rule?
Estimates excursion of wrist flex/ext (3cm), MCP ext (5cm), and FDP (7cm)
Indication for Brand tendon trx? What transferred?
High radial n. palsy; PT to ECRB, FCR to EDC, and PL to EPL.
N. transfer for high radial n. lesion?
Median branch of FDS to radial branch of ECRB and median branch of FCR to PIN
N. transfer for ulnar n. lesion?
AIN branch of PQ to deep motor branch of ulnar n.
Ranawat classification of neurologic impairment for RA pts?
I-subjective paraesthesias/pain, II-subjective weakness/UMN, III-objective weakness/UMN (A=amb, B=nonamb)
PADI that requires surgical stabilization in RA pts
<14 mm
Normal soft tissue shadows on C-spine XR?
6 mm at C2, 20 mm at C6
Indications for repair of pars defect?
Young pts with slippage < 10% and defect at L4 or above
Adult scoliotic curves at highest risk of progression?
R thoracic curves > 50 degrees
Which metatstatic tumors to the spine are radiosensitive?
Prostate, lymphoid, and breast (70%)
Normal distance b/t basion and dens in adults? Kids?
4-5 mm; 10 mm
Normal talocrural angle?
83 +/- 4 deg
Amount of blood loss required before see a drop in blood pressure?
15-30%
1st muscles to return after radial n. palsy? Last to return?
BR and ECRL; EPL and EIP
MC involved condyle with Hoffa fx fragment?
LFC
Which motion is not controlled by a Halo vest?
Axial distraction
3 structures that insert distal to the coranoid tip?
Capsule (5 mm), brachialis (11 mm), anterior band MCL (18 mm)
Last muscle to return after alleviation of PIN n. palsy?
EIP
Order of ossification of carpal bones?
Capitate (at 1 y/o) then progress clockwise on PA view of right hand (hamate, triquetrum, lunate, scaphoid, trapezium, trapezoid, and pisiform)
2 structures that attach to the scaphoid tubercle?
TCL and APB
2 nn. that leave the greater sciatic foramen and re-enter the pelvis through the lesser sciatic foramen?
Pudendal and n. to obturator internus
Mneumonic for nn. that leave the greater sciatic notch inferior to the piriformis (lateral to medial)?
POP’S IQ (Pudendal, Obturator internus, Posterior femoral cutaneous, Sciatic, Inferior gluteal, Quadratus femoris
Origin of the a. to the ligamentum teres?
Obturator a.
What makes up the floor of the popliteal fossa?
Plantaris
Relationship of lumbricals and IO to transverse MT ligament in the foot?
Lumbricals plantar, IO dorsal
What 2 aa. form the plantar arch in the foot?
Deep plantar a. (branch of DP) and lateral plantar a. (branch of PT)
Artery MC embolized for pelvic fx with hemodynamic instability?
Superior gluteal a. (branch of internal iliac)
Innervation of the SemiT?
L5 (tibial branch of the sciatic)
Immunostain for Langerhans Cell histiocytosis?
S100, CD1A
Immunostain for lymphoma?
CD20
Immunostain for chordoma?
Keratin, S100
Immunostain for myeloma?
CD138
Immunostain for adamantinoma?
Keratin
DDx for posterior spine lesions?
ABC, osteoid osteoma, and osteoblastoma
4 negative prognostic factors for osteosarcoma s/p treatment with chemo?
Expression of P-glycoprotein, high serum alk phos, high LDH, and absence of anti-shock protein 90 Abs
Innervation of the plantaris?
Tibial branch of sciatic
Key lab test for hypophosphatemic rickets?
Increased urinary phosphoethanolamine
% elongation of a nerve that leads to decreased microcirculation? Disruption of axons?
8%; 15%
2 x-linked dominant disorders?
X-linked hypophosphatemic (vitamin-D resistant) rickets and Leri-Weill dyschondrosteosis
Key difference b/t acute and subacute osteo?
Subacute osteo can cross the physis
3 EKG changes that can be seen with PE?
RBBB, right axis deviation, and T-wave inversion
Best physical measure of nutritional status?
Arm circumference
Definition of visco-elastic behavior?
Stress-strain behavior is time- and rate-dependent (modulus increases as strain rate increases)
Believed to be the glue that hold the collagen network together?
Type IX collagen