2020 Flashcards
In orthopaedics, inflammation can affect bone healing during fracture care. What is True?
a. Systemic inflammation seen in DM and RA do not affect bone healing.
b. NSAIDS and COX-2 inhibitors can decrease the production of prostaglandins during the acute inflammatory phase and affect bone healing.
c. Debriding/ evacuating the fracture hematoma can increase bone healing.
d. Micromotion of interfragmentary pieces and high strain environment increased intramembranous and endochondral bone healing.
B
A - False, chronic systemic inflammation affects bone healing. Rheumatoid, DM. HbA1c >7%
B - Correct mechanism and animal models shown decreased endochondral ossification in absence of COX-2 enzyme. Indomethacin is the only drug that has truly been shown to delay fracture healing of diaphyseal fractures.
C - Hematoma is the first phase of fracture healing, and necessary to ultimate union, clearing of hematoma necessitates red’n though. Hematoma stimulates the local inflammatory cascade, including the migration of PMNs. In animal models, removal of the fracture hematoma leads to impaired fracture healing.
D - Low strain <2% = primary (intramembranous) healing, high strain 2-10% = secondary (enchondral) healing.
What is the best strategy to decrease instability in THA?
a. Shortening length <10mm, maintaining offset, posterior approach
b. BMI <20, shortening length <10 mm, posterior approach
c. BMI >30, maintaining offset, judging anteversion off native TAL
d. Shortening length <5mm, maintaining offset, judging anteversion off native TAL
D
Read this as avoid shortening them
Independent risk factors for dislocation in primary THA
Spinal fusion, neurological/cognitive disorder, obesity
Pediatric Chance Fracture
a. Can happen anywhere in the thoracic and lumbar spine
b. Can be missed and mistaken for burst or compression fractures
c. Rarely presents with vascular injury
d. Often associated with neurologic injury
B
J. Ped. Ortho. 2019 - Chance fractures in pediatric population are often misdiagnosed.
5/7 patients with chance fractures were initially misdiagnosed
3 - Compression
1 - Burst
1 - MSK pain
All injuries from T12-L3
None of the patients had neurologic injury
JAAOS 2013
Concomitant visceral and head injuries are common and occur in approximately 40% of pediatric patients with flexion-distraction injuries
Two procedures are found to have the same medical benefits. Which of the following is the most appropriate way to assess cost to find a difference?
a. Cost Benefit
b. Cost Effectiveness
c. Cost Utilization
d. Cost Minimization
D
Cost-minimization analysis (CMA): a determination of the least costly among alternative interventions that are assumed to produce equivalent health outcomes.
Cost-effectiveness analysis: a comparison of interventions regarding costs in monetary units and outcomes expressed in quantitative nonmonetary health units, e.g., reduced mortality or morbidity.
Cost-utility analysis: a form of CEA that compares costs in monetary units with health outcomes regarding their utility and mortality, which is expressed in quality-adjusted life years (QALYs). QALY is a generic outcome measure that takes morbidity and mortality gains into account
Cost-benefit analysis: compares costs and health benefits (and risks), all of which are quantified in common monetary units
In c-spine flexion-distraction trauma, which of the following is a relative contraindication to ACDF at the C5-C6 level? (REPEAT 2018)
a. C5 superior process fracture
b. Anterior annulus tear
c. C6 facet fracture
d. C6 superior end plate fracture
D
Review of 87 patients with facet (75% bilateral, 25% unilateral) dislocations, Johnson et al reported a 13% radiographic failure rate with single-segment ACDF in traumatic cervical flexion distraction injuries that correlated with the presence of endplate compression fracture and facet fractures on injury radiographs
Ollier’s disease, all are true except?
a. Patients present with painless deformity
b. Usually diagnosed when skeletally immature
c. Usually metaphyseal lesion
d. Usually bilateral diaphyseal long bone involvement
D
A - can be painful, although most common is painless deformity (dysplastic, short, wide)
B - most common in first two decades of life in true ollier’s… if isolated enchondroma though then usually skeletally mature)
C - lesions mostly diaphyseal and metaphyseal
D - usually asymmetric and unilateral
85 yo F with TKA and ORIF 4 months ago. X-rays show TKA is loose. Plate failing. Crossed wires. Significant bone loss of distal femur. What is the best treatment? Also had a previous patellectomy. No patella on lateral view.
a. Hinged knee brace and non-weight bearing for 6 weeks
b. Revision TKA
c. Re-do ORIF
d. Revision with hinged distal femur endoprosthesis
D
General indications for a hinge: significant bone loss (involving epicondyles), significant collateral disruption (especially MCL), extension mechanism disruption
Best radiographic sign on AP pelvis to assess focal acetabulum anterior overcoverage vs retroversion?
a. Posterior wall sign
b. Ischial spine sign
c. Crossover sign
d. Retroversion index
A
2024F consensus
Posterior wall sign: present when the posterior wall of the acetabulum is medial to the centre of the femoral head.10,29,56 In the normal hip, the margin of the acetabular posterior wall intersects the centre of the femoral head.42 Its presence reveals an anomalous acetabular version even in the absence of cross-over sign which is associated with an early progression to osteoarthrosis
Distal humerus fracture what is false?
a. Need to use locking screws in distal fragment
b. Use longest screws possible
c. Screws should interdigitate
d. Screws should try to get fixation in every fragment
A
O’Driscoll SW. Optimizing stability in distal humeral fracture fixation. Journal of shoulder and elbow surgery. 2005 Jan 1;14(1):S186-94.
General principles: (1) fixation in the distal fragment must be maximized, and (2) all fixation in distal fragments should contribute to stability between the distal fragments and the shaft.
8 technical objectives:
(1) every screw in the distal fragments should pass through a plate;
(2) engage a fragment on the opposite side that is also fixed to a plate;
(3) as many screws as possible should be placed in the distal fragments;
(4) each screw should be as long as possible;
(5) each screw should engage as many articular fragments as possible;
(6) the screws in the distal fragments should lock together by interdigitation, creating a fixed-angle structure;
(7) plates should be applied such that compression is achieved at the supracondylar level for both columns; and
(8) the plates must be strong enough and stiff enough to resist breaking or bending before union occurs at the supracondylar level.
Regarding bone resorption, all true except:
a. IL-10 activates osteoclasts
b. Calcitonin directly interacts with osteoclasts through cell-surface receptors
c. IL-1 activates osteoclasts
d. Osteoclasts are responsible for bone resorption in Multiple Myeloma
A
A - FALSE - IL-10 inhibits osteoclasts
15 years old patient with difficulty walking, poor balance, poor fine motor coordination, dysarthria, diminished proprioception and diminished deep tendon reflexes, muscle weakness, bilateral cavus, and scoliosis. What disease do they have?
a. Friedrich ataxia
b. Spinal muscular atrophy
c. Duchenne muscular dystrophy
d. CMT
A
Friedreich’s ataxia (FRDA) is a genetic, progressive, neurodegenerative movement disorder, with a typical age of onset between 10 and 15 years.
Triad: ataxia, areflexia of knees and ankles, upgoing Babinski
Also associated with cavovarus, scoliosis, cardiomyopathy
Autosomal recessive
Most common spinocerebellar degenerative disease
About a third of the people with FRDA develop diabetes mellitus. The symptoms and clinical findings associated with FRDA result primarily from degenerative changes in the sensory nerve fibers at the point where they enter the spinal cord in structures known as dorsal root ganglia. This results in secondary degeneration of nerve fibers in the spinal cord which leads to a deficiency of sensory signals to the cerebellum, the part of the brain that helps to coordinate voluntary movements
SMA
Autosomal recessive, SMN gene
Normal intelligence and sensation
Hypotonia, decreased DTRs, areflexia, symmetrical limb and truncal weakness
Scoliosis
Hip dislocation/subluxation
Type I/2/3
Type I very severe, type II intermediate, type III ambulatory until adolescence
Respiratory function big concern - resp. Consult pre-op. Blood loss issue too. Tend to fix to pelvis in spine.
REMEMBER TREATMENT FOR SMA IS AVAILABLE
Nusinersen (SPINRAZA)
The drug is used to treat spinal muscular atrophy associated with a mutation in the SMN1 gene. It is administered directly to the central nervous system (CNS) using intrathecal injection.[1]
In clinical trials, the drug halted the disease progression. In around 60% of infants affected by type 1 spinal muscular atrophy, it improves motor function
Which is true concerning modalities for prevention of surgical site infections (SSI)?
a. Vancomycin is more cytotoxic than gentamycin and cipro when used in wounds
b. Intranasal mupirocine preoperatively was shown to not diminish SSI
c. Adhesive drapes are indicated in shoulder surgery
d. Chlorhexidine efficacy is cumulative and works best the longer it stays on the skin
D
1 - False - Topical Vanco has shown efficacy in many orthopedic procedures including spine and open fracture. No evidence for gent/cipro
2 - Journal of the American College of Surgeons
“American College of Surgeons and Surgical Infection Society: Surgical Site Infection Guidelines, 2016 Update”
The use of nasal mupirocin alone reduces S aureus SSI risk
Mupirocin ointment for preventing Staphylococcus aureus infections in nasal carriers (Cochrane Database Syst Rev (4) (2008)
3 - Webster J., Alghamdi A. Use of plastic adhesive drapes during surgery for preventing surgical site infection. Cochrane Database Syst Rev. 2015;(4):CD006353
No difference for adhesive drapes
4 - True - needs to dry to have maximum effect. Cumulative Some research has shown that chlorhexidine needs to dry on the skin for maximal effect, which is a limiting factor in bathing. In a recent study by Edmiston and colleagues, a protocol of 2 to 3 sequential showers with 4% chlorhexidine gluconate with a 1-minute pause before rinsing resulted in maximal skin surface concentrations.
In cerebral palsy, what MOST influences outcome of upper extremity surgery?
a. Spasticity
b. Contracture
c. Proprioception and stereognosis
d. Age
C
JAAOS 2010 Upper Extremity Surgery in Children with Cerebral Palsy
Lomita C, Ezaki M, Oishi S. Upper extremity surgery in children with cerebral palsy. JAAOS-Journal of the American Academy of Orthopaedic Surgeons. 2010 Mar 1;18(3):160-8.
In cerebral palsy, sensory deficits most commonly exist in the patient’s stereognosis, that is, the ability to perceive an object through sense of touch. May also see deficits in 2 point discripination and proprioception.
Although a sensory deficit should not preclude a patient from surgical treatment, more reliable results are generally seen in patients with near-normal sensory findings
In general, a higher level of use and recognition of the affected upper extremity or extremities leads to more reliable surgical outcomes
In spinal cord injury, what does the zone of partial preservation refer to?
a. Incomplete spinal cord injury with partial preservation of motor innervation caudally
b. Incomplete spinal cord injury with partial preservation of sensory innervation caudally
c. Complete spinal cord injury with partial preservation of innervation caudally
d. Complete spinal cord injury with partial preservation of motor innervation caudally
C
Zone of partial preservation (ZPP): This term, used only with complete injuries (no sacral sparing), refers to those dermatomes and myotomes caudal to the sensory and motor levels that remain partially innervated. The most caudal segment with some sensory and/or motor function defines the extent of the sensory and motor ZPP respectively and are documented as four distinct levels (R-sensory, L-sensory, R-motor, and L-motor).
Basic science cartilage question regarding articular cartilage, what is FALSE?
a) Aging cartilage has decreasing modulus of elasticity, OA has increased
b) Most collagen is in superficial layer and provides tensile strength
c) Most water is superficial compared to deep
d) 95% type II collagen
A
Effect of aging on articular cartilage is: INCREASED modulus of elasticity, and OA DECREASES it.
95% of collagen is type 2. Provides cartilaginous framework and provides tensile strength. 80% of water content is in the superficial layers
Which bone substitute has been shown to be equivalent to autograft for hind foot fusions:
a) Tricalcium phosphate with BMP 7
b) BMP 2
c) PRP
d) PDGF
D
Daniels et al 2011 Foot and ankle international. RTC of PDGF vs autograft, PDGF group had fusion rate of 84% at 24 weeks, autograft had 65% fusion rate.
Canadian study out of Toronto and Ottawa.
Which of the following should get consideration for early surgical management for rotator cuff tear?
a. Pseudoparalysis following acute on chronic tear
b. Well functioning acute on chronic tear
c. Atraumatic tear >15mm
d. Associated with biceps tear
A
JSES 2006: Lahteenmaki etal: results of early operative treatment of RTC with acute symptoms.
26 pts operated on within 3 weeks of symptoms ( whether new symptoms OR significant worsening of old symptoms) and evidence of a full thickness tear. Excellent outcomes in 20 pts (70%) using UCLA shoulder rating scale. “ early operative treatment appears to be better for RTC tears with sudden onset of symptoms and poor function to achieve maximal return to shoulder function”
OCD lesion of talus. Atraumatic. Where is it located: (REPEAT 2018)
a. Posteromedial
b. Anterolateral
c. Posterolateral
d. Anteromedial
A
Black book:
medial= more common, non traumatic, larger and deeper, more posterior
lateral= traumatic, smaller and shallower, more anterior
Guy with pain radiating from posterior thigh to foot. Positive Straight leg raise test manoeuver, positive femoral nerve stretch manoeuver. What is the most likely lesion ?
a. L4-L5 herniated disk causing foraminal stenosis
b. Central L4-L5 herniated disk
c. L5-S1 postero-lateral herniated disk
d. Far lateral L3-L4 herniated disk
A
Femoral nerve stretch test:
The femoral nerve stretch test can identify spinal nerve root compression, which is associated with disc protrusion and femoral nerve injury. It can reliably identify spinal nerve root compression for L2, L3, and L4.[2] It is usually positive for L2-L3 and L3-L4 (high lumbar) disc protrusions, slightly positive or negative in L4–L5 disc protrusions, and negative in cases of lumbosacral disc protrusion
L1 Nerve - pain and sensory loss are common in the inguinal region. Hip flexion weakness is rare, and no stretch reflex is affected.
L2-L3-L4 Nerves - back pain radiating into the anterior thigh and medial lower leg; sensory loss to the anterior thigh and sometimes medial lower leg; hip flexion and adduction weakness, knee extension weakness; decreased patellar reflex.
L5 Nerve - back, radiating into buttock, lateral thigh, lateral calf, and dorsum foot, great toe; sensory loss on the lateral calf, dorsum of the foot, webspace between first and second toe; weakness on hip abduction, knee flexion, foot dorsiflexion, toe extension and flexion, foot inversion and eversion; decreased semitendinosus/semimembranosus reflex.
S1 Nerve - back, radiating into buttock, lateral or posterior thigh, posterior calf, lateral or plantar foot; sensory loss on the posterior calf, lateral or plantar aspect of foot; weakness on hip extension, knee flexion, plantar flexion of the foot; Achilles tendon; Medial buttock, perineal, and perianal region; weakness may be minimal, with urinary and fecal incontinence as well as sexual dysfunction.
S2-S4 Nerves - sacral or buttock pain radiating into the posterior aspect of the leg or the perineum; sensory deficit on the medial buttock, perineal, and perianal region; absent bulbocavernosus, anal wink reflex.
22F growing mass in hand. Xray showed surface lesion ulnar aspect of proximal phalanx with osseous matrix. Lesion was not continuous with medullary canal with no associated periosteal reaction/bony reaction of underlying bone. MRI - lesion dark on T1 and bright on T2 Fat Sat, highest signal peripherally. Normal signal intensity of the cortex and bone marrow of the underlying bone. No continuity with medullary canal on MRI either. What is the MOST likely diagnosis?
a. Bizarre parosteal osteochondromatous proliferation (Nora’s Lesion)
b. Osteoma
c. Periosteal chondrosarcoma
d. Osteochondroma
A
Nora lesion:
a rare benign parosteal osteochondromatous proliferation involving feet and hand. Aggressive features on imaging and confusing results on histopathological studies make its diagnosis difficult. Since the time of its discovery, only few cases have been reported in the literature.
Predilection for the hands and feet
Rapid growth
Typically occurs in young adults- 1:1 M vs F
Treatment is excision- high recurrence rate- approx 50%
Rare AF- mainly case reports
About Bone forming tumors, which one is false?
a. Osteoid osteoma has limited capacity to grow
b. Bone island common in pelvis, spine, rib, skull
c. Melorheostosis is non evolutive
d. Osteoblastoma has an array of imaging findings
C
Melos = limb, rheos = flow
Flowing hyperosteosis
Rare, non-heritable, sclerosis bone dysplasia
Abnormalities in both enchondral and intramembranous ossification
Symptoms
-Progressive pain interspersed with periods of disease arrest
Also known as Leri disease
Demographics
Manifests in adolescence or early adulthood
Symptoms
Pain and limb deformity soft-tissue involvement
Leads to disabling joint contractures
Joint ankylosis can also be seen
Overlap syndrome
Melorheostosis associated with osteopoikilosis and osteopathia
Radiographic appearance
“Dripping candle wax” periosteal hyperostosis
Cortical or medullary hyperostosis along one side of a long bone or multiple adjacent bones in a sclerotomal distribution
CT
Cortical hyperostosis demonstrated
Demonstrates the amount of endosteal involvement
MRI
Can help determine the amount of soft-tissue fibrosis
Bone scan - can be hot
Histology
Diffuse cortical sclerosis with small haversian systems, similar to that seen in osteomas and enostoses
Soft-tissue masses can be composed of a mixture of bone, cartilage, fibrous and adipose tissue
Monostotic disease can be confused with mature myositis ossificans, osteoid osteoma (with no visible nidus), and parosteal osteosarcoma
Treatment
Symptomatic
5 yo Kid with CP, walks independently with walker, can sit independently but needs trunk support when using his hands, can get up the stairs with mom’s help, get up with hand support on the table. What is his GMFCS level?
a. II
b. III
c. IV
d. V
B
All are risk factors for progression in AIS (adolescent idiopathic scoliosis), except:
a. Risser score
b. Growth Potential
c. Degree of Thoracic Kyphosis
d. Female
C
Tibia vara from Focal Fibrocartilaginous dysplasia, which is not associated:
a) Associated with proximal medial tibial physis
b) Abrupt varus at metaphyseal/diaphyseal junction
c) Cortical sclerosis at the medial cortex
d) Lucency proximal to cortical sclerosis
A
B/C/D- true, straight from orthobullets.
Young patient 3 days post-trauma (fell off a swing?). Presents with head tilted to the right and gaze rotated to the left.
Cervical x-rays were done and open-mouth odontoid view shows lateral mass asymmetry. What is the best next step:
a. Cervical MRI scan
b. Lateral cervical x-rays with 4.5 kg of traction
c. C1-C2 CT Scan
d. Oblique cervical x-rays
C
Atlantoaxial Rotatory Displacement is a pediatric cervical spine rotatory instability caused by C1-C2 subluxation or facet dislocation The most common presentation is a young child who presents with torticollis
SCM spasm happens on opposite side of the facet subluxation. (chin will point away from affected facet). This is protective to prevent further subluxation.
Dynamic CT
is diagnostic gold standard
take CT with head straight forward, and then in maximal rotation to right and left
will see fixed rotation of C1 on C2 which does not change with dynamic rotation
