Anatomy and Basic Sciences (2008-2019) Flashcards

Question

25. The main branch of the medial femoral circumflex artery is anterior to all of the following structures EXCEPT? 1. Superior gemellus 2. Inferior gemellus 3. Obturator externus 4. Obturator internus

Answer 1

ANSWER: C (Obturator externus) * 2014 * Gautier (JBJS Br 2000) Anatomy of the medial femoral circumflex artery and its surgical implications. * The course of the deep branch of the MFCA was constant in its extracapsular segment. In all cases there was a trochanteric branch at the proximal border of quadratus femoris spreading on to the lateral aspect of the greater trochanter. This branch marks the level of the tendon of obturator externus, which is crossed posteriorly by the deep branch of the MFCA. * Course of the deep branch of MCFA * Profunda femoris * Runs towards intertrochanteric crest between the pectineus (medially) and Iliopsoas (laterally) on the inferior border of the obturator externus * Identify posteriorly between QF and IG * Gives off branches: * Constant branch --\> branches at inferior QF, crosses GT (trochanteric branch) * Main division crosses posterior to tendon of OE, and anterior to SG, OI, IG * Perforates the capsule just cranial to the insertion of the tendon to the SG and distal to the tendon of the piriformis * Divides into 2-4 terminal retinacular branches

Answer 2

ANSWER: C (Adductor Magnus) * 2016 * Adductor magnus has contributions from both sciatic and obturator nerves TRICK: think Magnus has Many innervations

Answer 3

ANSWER: B (Cluneal) * 2009, 2013 * Netter's Anatomy (p.243) * Superior gluteal has no sensory innervation * LFCN = lateral thigh * PFCN = posterior thigh, does have some contribution to inferior buttocks through inferior cluneal branch * Superior Cluneal (L1-3 dorsal rami) = superior 2/3 buttocks * Medial Cluneal (S1-3 dorsal rami) =sacral and medial buttocks

Answer 4

ANSWER: B (TFL innervated by SGN) * 2016 * Netter's Anatomy: * Gluteus maximus = inferior gluteal * Piriformis = nerve to piriformis * OI = nerve to obturator internus

Answer 5

ANSWER: B (Superior Lateral) * 2016 * Netter's Orthopedic Anatomy: * Foramen appears to be at the superomedial or superolateral depending on orientation of obturator foramen * JAAOS - Nerve Injuries in Total Hip Arthroplasty: * "obturator nerve arises from the L2, L3, and L4 nerve roots within the posterior psoas and then emerges medially at the sacral ala to travel along the iliopectineal line" * "the obturator nerve exits the pelvis at the superior aspect of the obturator foramen, where it supplies the adductor muscles"

Answer 6

ANSWER: A (Medial Femoral Circumflex) * 2016 * Both femoral artery and profunda could be damaged with ANTERIOR retractor * Superior gluteal is possible but is generally more proximal than proximal femur (acetabular exposures) * Generally injured with dissection, not retractors if posterior approach to the hip * Charles: perforators of the profunda femoris, depends on how proximal, medial Fem. Circumflex makes most sense if most proximal part.

Answer 7

ANSWER: B (TFL and Sartorius) * 2013 * Smith-Pete Exposure

Answer 8

ANSWER: A (Medial sural cutaneous nerve) * 2011 * Hoppenfeld

Answer 9

ANSWER: C (infraspinatus not part of the quadrangular space) * 2012 * Netter's Orthopedics (p96) * Quadrangular space: * Teres minor, teres major, long head of triceps, humerus * Axillary nerve, posterior circumflex artery, humeral artery

Answer 10

ANSWER: B (Should be posterior radial collateral artery – poorly recalled answer) * 2009 * The flap is supplied by the radial collateral artery. It originates from the brachial artery and wraps posteriorly around the humerus, descending on the lateral aspect of the humerus and then branching into an anterior and posterior segments. The posterior branch supplies the lateral arm and lateral forearm flaps. * Brachial artery --\> profunda brachii --\> posterior radial collateral artery

Answer 11

ANSWER: B (loss of thumb IP extension) * 2016 * PIN palsy * PIN does not have cutaneous sensory function (just capsule)

Answer 12

ANSWER: A * 2011 * Noda K - Interosseous Membrane of the Forearm: An Anatomical Study of Ligament Attachment Locations * The most representative component of the IOM is the central band * Runs obliquely from the proximal radial shaft to the distal ulnar shaft

Answer 13

ANSWER: B * 2012, 2015, 2016 (variants) * McCann PA (Ann R Coll Surg 2012) The cadaveric anatomy of the distal radius * The structure most at risk was the palmar cutaneous branch of the median nerve. It was located on average 3.4mm from the FCR tendon * Radial artery 7.8mm * Median nerve 8.9mm * SRN 24.4

Answer 14

ANSWER: D * 2008 Course * arises 5-8 cm distal to lateral epicondyle * passes between two heads of pronator teres * runs along the volar surface of the **FDP** * courses distally along the interosseous membrane * terminates in PQ near wrist joint

Answer 15

ANSWER: B * 2009 * Only D2/3 * D3/4 by ulnar nerve

Answer 16

ANSWER: A * 2013

Answer 17

ANSWER: C * 2009

Answer 18

* Weston WC (Ann Rheum Dis 1999) Clinical features and outcome of septic arthritis in a single Uk Health District 1982-1991 * Risk Factors of Mortality: * Confusion at presentation * Age \> 65 * Multiple joint sepsis * Elbow involvement * Risk Factors of Morbidity * Age \> 65 * DM * Open surgical drainage * Gram positive infection other than S aureus * Gupta MN (Rheum 2001) Prospective 2 year study of 75 patients with adult-onset septic arthritis * Poor prognosis/mortality * Elevated WBC at presentation * Development of abnormal renal function * Shirtliff ME (Clin Microbiol Rev 2002) Acute Septic Arthritis * Underlying joint disease (delay in diagnosis) * Poly-articular involvement

Answer 19

What antibiotic to use ? * Clindamycin * Piptazo also an option * Redfern J (JOT 2016) Surgical site infections in patients with type 3 open fractures : comparing cefazolin plus genta vs piptaz What Immunization? Tetanus Prone Wound: * More than 6 hours old * Stellate * Avulsion or abrasion configuration * Depth more than 1 cm * Mechanism: missile, crush, burn, frostbite * Signs of infected/devitalized tissue * Grossly contaminated What surgical treatment to implement? * Irrigation and debridement * Early flap coverage if needed (shouldn't be needed for grade II) * Reamed IM nail

Answer 20

ANSWER: C * 2016 * See 2009, 2013 question below Similar to 2013 Questions, but Vanco an option for answer on this * Their Reference: * Bratzler, D. W., Dellinger, E. P., Olsen, K. M., Perl, T. M., Auwaerter, P. G., Bolon, M. K., et al. (2013). Clinical Practice Guidelines for Antimicrobial Prophylaxis in Surgery. Surgical Infections, 14(1), 73–156. doi:10.1089/sur.2013.9999 * Talks about clean procedures, those with hardware * MRSA = use vanco, some decolonization stuff * JAAOS 2015 – MRSA Infections in Kids * Vancomycin at 15mg/kg q6h * If stable: then consider Clindamycin at daily dose of 40mg/kg * If regional clindamycin resistance is low (\<10%)

Answer 21

ANSWER: A * 2009, 2013 * Antimicrobial prophylaxis for surgery: An Advisory Statement from the National Surgical prevention project * .."there is no evidence that routine use of vancomycin for prophylaxis in institutions with perceived high rates of MRSA infection will result in fewer SSIs than do agents such as cefazolin" * Bhandari - Evidence Based Medicine * "cephalosporins remain the standard prophylactic antibiotic. MRSA screen and treatment of carriers is not universal. Vancomycin is not routinely used for surgical prophylaxis, but may be used in patients with known or suspected MRSA infection or carriage" * If confirmed colonization or prev MRSA in one pt would give ancef and vanco together.

Answer 22

ANSWER:A * 2012 * JAAOS 1996 - HIV transmission in surgical setting * Step by step minimization of sharps * Use of instrument ties * Use of magnetic trays or basins to pass sharps * Lower blood contact if double gloved

Answer 23

ANSWER: D * 2012 * CDC Guidelines * Enzyme immunoassay (EIA) testing for C. difficile toxin A and B is rapid but is less sensitive than the cell cytotoxin assay, and it is thus a suboptimal alternative approach for diagnosis (B-II). * Metronidazole (flagyl) is the drug of choice for the initial episode of mild-to-moderate CDI. The dosage is 500 mg orally 3 times per day for 10–14 days. (A-I) * Vancomycin is the drug of choice for an initial episode of severe CDI. The dosage is 125 mg orally 4 times per day for 10–14 days. (B-I) * Vancomycin administered orally (and per rectum, if ileus is present) with or without intravenously administered metronidazole is the regimen of choice for the treatment of severe, complicated CDI. The vancomycin dosage is 500 mg orally 4 times per day and 500 mg in approximately 100 mL normal saline per rectum every 6 hours as a retention enema, and the metronidazole dosage is 500 mg intravenously every 8 hours. * Receipt of antimicrobials increases the risk of CDI because it suppresses the normal bowel flora, thereby providing a “niche” for C. difficile to flourish. Both longer exposure to antimicrobials, as opposed to shorter exposure,47 and exposure to multiple antimicrobials, as opposed to exposure to a single agent, increase the risk for CDI.47 Nonetheless, even very limited exposure, such as single-dose surgical antibiotic prophylaxis, increases a patient’s risk of both C. difficile colonization82 and symptomatic disease.

Answer 24

ANSWER: B (MRI most sensitive) * 2012, 2015 * AAOS Review: * MRI can detect subtle marrow changes associated with early osteomyelitis with almost 100% sensitivity * JPO 2015 - Pediatric Osteoarticular Infection Update * MRI remains the best available study for anatomic detail * Addition of gad improves abscess detection * JAAOS - Acute Hematogenous OM in Children * MRI has a reported sensitivity of 88-100%. Technetium 99m bone scintigraphy …reported sensitivity from 84-100%

Answer 25

ANSWER: D * 2016 * Kocher MS (JBJS 1999) * Criteria: NWB, WBC \> 12, Temp \> 38.3oC, ESR \>40 * 0 – 0.2%; 1 – 3.0%; 2 – 40.0%; 3 – 93.1%; 4- 99.6% * Kocher MS (JBJS 2004) * Validation of the tool * 0 – 0.2%; 1 – 9.5%; 2 – 35.0%; 3 – 72.8%; 4 – 93.0%

Answer 26

ANSWER: C * Presumably a biofilm question * Lancet 2004 – Osteomyelitis: * A biofilm is a microbial community characterized by cells that attach to substratum or interface or to each other, embedded in a matrix of extracellular polymeric substance, and showing an altered phenotype in terms of growth, gene expression, and protein production * Bacterial resistance through low metabolic rates, adaptive stress responses and downregulated cell division  * JAAOS 2015 – Novel developments in the prevention, diagnosis and treatment of Periprosthetic joint infections * Allows bacterial population to evade antimicrobial therapies and immune response of the host * Bacteria may go into quiescent state once in film, making them even harder to kill (so not growing) * 1000x more resistant to antibiotics * Low metabolic levels and drastically down regulated cell division * Dispersion via detachment à micro-colonies * S. aureus can hide in osteoblast to evade immune system * JAAOS – Chronic Infection * Chronic osteomyelitis is a biofilm infection caused by complex colonies of phenotypically diverse microorganisms propagating freeing within a microbial-based, polysaccharide matrix that provides an immunity to host defenses and systemic concentrations of antimicrobial agents * Biofilms: Survival mechanisms of clinically relevant microorganism (Clin Microb Reviews 2002) * The new definition of a biofilm is a microbially derived sessile community characterized by cells that are irreversibly attached to a substratum or interface or to each other, are embedded in a matrix of extracellular polymeric substances that they have produced, and exhibit an altered phenotype with respect to growth rate and gene transcription

Answer 27

ANSWER: A * 2008 * Management of extremity trauma and related infections occurring in the aquatic environment * Animals inoculated with ocean water have infection with Vibrio, aeromonas hydrophilia, pseudomonas putrefaciens * Still the most common infection is staph and strep * Clostridium species are present in seawater, patients treated with wounds in brackish or ocean water should be treated with tetanus * Vibrio are common in oceans and costal waterways * Present with rapidly progressive cellulitis * Doxycycline, ceftazidime, cipro * Aeromonas hydrophilia * Freshwater lakes, ponds, streams * Can develop bullous cellulitis * Ciprofloxacin, ceftazidime